On the origin of the increased tissue iron content in graded magnesium deficiency states in the rat

To investigate the mechanism of tissue Fe accumulation in graded Mg deficiency rats were fed on diets of different Mg contents (70, 110, 208, 330, and 850 mg Mg/kg) for 10, 20, and 30 d during rapid growth. There was no significant impact of Mg deficiency or high luminal Mg concentrations on intestinal59Fe transferin vitroorin vivo. Plasma Mg concentrations and body weight started to decrease after 10 d. Significant haemolytic anaemia was observed after 20 d with siderosis in liver and spleen developing in parallel. Anaemia showed no features of Fe deficiency or infiammation. Comparison between the 70 mg Mg/kg group and animals that received the same quantity of a Mg-adequate diet (850 mg Mg/kg) permitted estimation of quantities of Fe liberated by haemolysis and the increased Fe content in liver and spleen. Both variables showed a high degree of correlation, indicating that the excess of liberated haemoglobin Fe was stored in the tissue. The erythropoietic activity was high during rapid growth, i.e. at days 10 and 20 and decreased significantly after 30 d in all except the most Mg-deficient groups. However, haemolytic anaemia developed because even the high erythropoietic activity in the 70 and 110 mg Mg/kg groups was not sutlicient to recycle all haemoglobin Fe liberated by haemolysis. After 30 d of Mg-deficient feeding the erythrocyte Mg content had decreased to 40% of control values. According to the literature Mg-deficient erythrocytes have a decreased survival time which is likely to be the cause of the observed haemolysis.

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Contamination of erythropoietin by endotoxin: in vivo and in vitro effects on murine erythropoiesis

Blood ◽

10.1182/blood.v54.1.146.146 ◽

1979 ◽

Vol 54 (1) ◽

pp. 146-158 ◽

Cited By ~ 8

Author(s):

KS Zuckerman ◽

PJ Quesenberry ◽

J Levin ◽

R Sullivan

Keyword(s):

Significant Inhibition ◽

Erythropoietic Activity ◽

Limulus Amebocyte Lysate ◽

Endogenous Erythropoietin ◽

Significant Change ◽

In Vitro Effects ◽

Stimulation Of

Abstract Endotoxin was detected in all erythropoietin preparations tested and was removed from four lots, without loss of erythropoietic activity, by adsorption with limulus amebocyte lysate. Comparison of adsorbed (endotoxin-depleted) and nonadsorbed (endotoxin-containing) erythropoietin preparations demonstrated significant inhibition of CFU- e and BFU-e in vitro by nonadsorbed erythropoietin at concentrations higher than 0.25 U/ml and 2.0 U/ml, respectively. CFU-e and BFU-e were inhibited significantly by readdition in vitro of 10(-5)-10(-3) mug of endotoxin per unit of limulus-adsorbed erythropoietin. Administration of saline or 6 U of nonadsorbed or adsorbed erythropoietin twice a day for 4 days of CF1 mice resulted in reticulocyte counts of 2.1%, 9.9%, and 15.9%, respectively. Nonadsorbed erythropoietin resulted in a 29% decrease in erythropoiesis, a 42% decrease in CFU-e, and a 16% increase in granulopoiesis in the marrow, whereas adsorbed erythropoietin caused a 28% increase in erythropoiesis, no significant change in CFU-e and a 19% decrease in granulopoiesis in the marrow. Both preparations resulted in marked increases in splenic erythropoiesis and granulopoiesis. The effects of adsorbed erythropoietin are similar to those produced following stimulation of hematopoiesis by endogenous erythropoietin. Hemopoietic changes induced by nonadsorbed erythropoietin in vivo and in vitro are affected substantially by contamination of the erythropoietin preparations with endotoxin.

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Developmental regulation of heterochromatin-mediated gene silencing in Drosophila

Development ◽

10.1242/dev.125.12.2223 ◽

1998 ◽

Vol 125 (12) ◽

pp. 2223-2234 ◽

Cited By ~ 1

Author(s):

B.Y. Lu ◽

J. Ma ◽

J.C. Eissenberg

Keyword(s):

Cell Cycle ◽

Gene Silencing ◽

Mitotic Activity ◽

Larval Stage ◽

Developmental Regulation ◽

Promoter Strength ◽

Lacz Gene ◽

High Degree

The roles of differentiation, mitotic activity and intrinsic promoter strength in the maintenance of heterochromatic silencing were investigated during development using an inducible lacZ gene as an in vivo probe. Heterochromatic silencing is initiated at the onset of gastrulation, approximately 1 hour after heterochromatin is first visible cytologically. A high degree of silencing is maintained in the mitotically active imaginal cells from mid-embryogenesis until early third instar larval stage, and extensive relaxation of silencing is tightly associated with the onset of differentiation. Relaxation of silencing can be triggered in vitro by ecdysone. In contrast, timing and extent of silencing at both the initiation and relaxation stages are insensitive to changes in cell cycle activity, and intrinsic promoter strength also does not influence the extent of silencing by heterochromatin. These data suggest that the silencing activity of heterochromatin is developmentally programmed.

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Isolation and characterization of adrenocortical progenitors involved in the adaptation to stress

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1814072115 ◽

2018 ◽

Vol 115 (51) ◽

pp. 12997-13002 ◽

Cited By ~ 15

Author(s):

Charlotte Steenblock ◽

Maria F. Rubin de Celis ◽

Luis F. Delgadillo Silva ◽

Verena Pawolski ◽

Ana Brennand ◽

...

Keyword(s):

Lineage Tracing ◽

Differentiated Cells ◽

Isolation And Characterization ◽

Proliferation And Differentiation ◽

Response To Stress ◽

Steroidogenic Cells ◽

High Degree

The adrenal gland is a master regulator of the human body during response to stress. This organ shows constant replacement of senescent cells by newly differentiated cells. A high degree of plasticity is critical to sustain homeostasis under different physiological demands. This is achieved in part through proliferation and differentiation of adult adrenal progenitors. Here, we report the isolation and characterization of a Nestin+ population of adrenocortical progenitors located under the adrenal capsule and scattered throughout the cortex. These cells are interconnected with progenitors in the medulla. In vivo lineage tracing revealed that, under basal conditions, this population is noncommitted and slowly migrates centripetally. Under stress, this migration is greatly enhanced, and the cells differentiate into steroidogenic cells. Nestin+ cells cultured in vitro also show multipotency, as they differentiate into mineralocorticoid and glucocorticoid-producing cells, which can be further influenced by the exposure to Angiotensin II, adrenocorticotropic hormone, and the agonist of luteinizing hormone-releasing hormone, triptorelin. Taken together, Nestin+ cells in the adult adrenal cortex exhibit the features of adrenocortical progenitor cells. Our study provides evidence for a role of Nestin+ cells in organ homeostasis and emphasizes their role under stress. This cell population might be a potential source of cell replacement for the treatment of adrenal insufficiency.

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Transcriptomic analysis reveals a role for the nervous system in regulating growth and development of Fasciola hepatica juveniles

10.1101/2022.01.13.476286 ◽

2022 ◽

Author(s):

Emily Robb ◽

Erin McCammick ◽

Duncan Wells ◽

Paul McVeigh ◽

Erica Gardiner ◽

...

Keyword(s):

Nervous System ◽

Rapid Growth ◽

Growth And Development ◽

Liver Fluke ◽

Fasciola Hepatica ◽

Expression Profiles ◽

Neuronal Signalling ◽

Growth Development

Fasciola spp. liver fluke have significant impacts in veterinary and human medicine. The absence of a vaccine and increasing anthelmintic resistance threaten sustainable control and underscore the need for novel flukicides. Functional genomic approaches underpinned by in vitro culture of juvenile Fasciola hepatica facilitate control target validation in the most pathogenic life stage. Comparative transcriptomics of in vitro and in vivo maintained 21 day old F. hepatica finds that 86% of genes are expressed at similar levels across maintenance treatments suggesting commonality in core biological functioning within these juveniles. Phenotypic comparisons revealed higher cell proliferation and growth rates in the in vivo juveniles compared to their in vitro counterparts. These phenotypic differences were consistent with the upregulation of neoblast-like stem cell and cell-cycle associated genes in in vivo maintained worms. The more rapid growth/development of in vivo juveniles was further evidenced by a switch in cathepsin protease expression profiles, dominated by cathepsin B in in vitro juveniles and then by cathepsin L in in vivo juveniles. Coincident with more rapid growth/development was the marked downregulation of both classical and peptidergic neuronal signalling components in in vivo maintained juveniles, supporting a role for the nervous system in regulating liver fluke growth and development. Differences in the miRNA complements of in vivo and in vitro juveniles identified 31 differentially expressed miRNAs, notably fhe-let-7a-5p , fhe-mir-124-3p and, miRNAs predicted to target Wnt-signalling, supporting a key role for miRNAs in driving the growth/developmental differences in the in vitro and in vivo maintained juvenile liver fluke. Widespread differences in the expression of neuronal genes in juvenile fluke grown in vitro and in vivo expose significant interplay between neuronal signalling and the rate of growth/development, encouraging consideration of neuronal targets in efforts to dysregulate growth/development for parasite control.

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Transcriptomic-Based Quantification of the Epithelial-Hybrid-Mesenchymal Spectrum Across Biological Contexts

Biomolecules ◽

10.3390/biom12010029 ◽

2021 ◽

Vol 12 (1) ◽

pp. 29

Author(s):

Susmita Mandal ◽

Tanishq Tejaswi ◽

Rohini Janivara ◽

Syamanthak Srikrishnan ◽

Pradipti Thakur ◽

...

Keyword(s):

Cancer Cells ◽

Cancer Metastasis ◽

Expression Profiles ◽

Gene List ◽

Cellular Reprogramming ◽

Induced Pluripotent ◽

Patient Prognosis ◽

High Degree

Epithelial-mesenchymal plasticity (EMP) underlies embryonic development, wound healing, and cancer metastasis and fibrosis. Cancer cells exhibiting EMP often have more aggressive behavior, characterized by drug resistance, and tumor-initiating and immuno-evasive traits. Thus, the EMP status of cancer cells can be a critical indicator of patient prognosis. Here, we compare three distinct transcriptomic-based metrics—each derived using a different gene list and algorithm—that quantify the EMP spectrum. Our results for over 80 cancer-related RNA-seq datasets reveal a high degree of concordance among these metrics in quantifying the extent of EMP. Moreover, each metric, despite being trained on cancer expression profiles, recapitulates the expected changes in EMP scores for non-cancer contexts such as lung fibrosis and cellular reprogramming into induced pluripotent stem cells. Thus, we offer a scoring platform to quantify the extent of EMP in vitro and in vivo for diverse biological applications including cancer.

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Increased Carrier Peptide Stability through pH Adjustment Improves Insulin and PTH(1-34) Delivery In Vitro and In Vivo Rather than by Enforced Carrier Peptide-Cargo Complexation

Pharmaceutics ◽

10.3390/pharmaceutics12100993 ◽

2020 ◽

Vol 12 (10) ◽

pp. 993

Author(s):

Mie Kristensen ◽

Ragna Guldsmed Diedrichsen ◽

Valeria Vetri ◽

Vito Foderà ◽

Hanne Mørck Nielsen

Keyword(s):

Oral Delivery ◽

Molecular Size ◽

Therapeutic Peptide ◽

Enzymatic Stability ◽

Therapeutic Peptides ◽

Ph Dependent ◽

Pharmacologically Active ◽

High Degree

Oral delivery of therapeutic peptides is hampered by their large molecular size and labile nature, thus limiting their permeation across the intestinal epithelium. Promising approaches to overcome the latter include co-administration with carrier peptides. In this study, the cell-penetrating peptide penetratin was employed to investigate effects of co-administration with insulin and the pharmacologically active part of parathyroid hormone (PTH(1-34)) at pH 5, 6.5, and 7.4 with respect to complexation, enzymatic stability, and transepithelial permeation of the therapeutic peptide in vitro and in vivo. Complex formation between insulin or PTH(1-34) and penetratin was pH-dependent. Micron-sized complexes dominated in the samples prepared at pH-values at which penetratin interacts electrostatically with the therapeutic peptide. The association efficiency was more pronounced between insulin and penetratin than between PTH(1-34) and penetratin. Despite the high degree of complexation, penetratin retained its membrane activity when applied to liposomal structures. The enzymatic stability of penetratin during incubation on polarized Caco-2 cell monolayers was pH-dependent with a prolonged half-live determined at pH 5 when compared to pH 6.5 and 7.4. Also, the penetratin-mediated transepithelial permeation of insulin and PTH(1-34) was increased in vitro and in vivo upon lowering the sample pH from 7.4 or 6.5 to 5. Thus, the formation of penetratin-cargo complexes with several molecular entities is not prerequisite for penetratin-mediated transepithelial permeation a therapeutic peptide. Rather, a sample pH, which improves the penetratin stability, appears to optimize the penetratin-mediated transepithelial permeation of insulin and PTH(1-34).

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Ultrasound-Mediated Drug Delivery in Cancer Therapy: A Review

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.18877 ◽

2020 ◽

Vol 20 (12) ◽

pp. 7211-7230 ◽

Cited By ~ 1

Author(s):

Nour M. Al Sawaftah ◽

Ghaleb A. Husseini

Keyword(s):

Drug Delivery ◽

Targeted Drug Delivery ◽

Controlled Drug Release ◽

Medical Applications ◽

Adverse Side Effects ◽

Medical Diagnostic ◽

High Degree ◽

Ultrasound Parameters

The use of ultrasound as a medical diagnostic tool began in the 1940s. Ever since, the medical applications of ultrasound have included imaging, tumor ablation, and lithotripsy; however, an ever-increasing body of literature demonstrates that ultrasound has potential in other medical applications, including targeted drug delivery. Site-specific drug delivery involves delivering drugs to diseased areas with a high degree of precision, which is particularly advantageous in cancer treatment as it would minimize the adverse side effects experienced by patients. This review addresses the ability of ultrasound to induce localized and controlled drug release from nanocarriers, namely micelles and liposomes, utilizing thermal and/or mechanical effects. The interactions of ultrasound with micelles and liposomes, the effects of the lipid composition, and ultrasound parameters on the release of encapsulated drugs are discussed. In addition, a survey of the literature detailing some in vitro and in vivo ultrasound triggered drug delivery systems is presented.

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Disruption of Sept6, a Fusion Partner Gene of MLL, Does Not Affect Ontogeny, Leukemogenesis Induced by MLL-SEPT6, or Phenotype Induced by the Loss of Sept4

Molecular and Cellular Biology ◽

10.1128/mcb.25.24.10965-10978.2005 ◽

2005 ◽

Vol 25 (24) ◽

pp. 10965-10978 ◽

Cited By ~ 39

Author(s):

Ryoichi Ono ◽

Masafumi Ihara ◽

Hideaki Nakajima ◽

Katsutoshi Ozaki ◽

Yuki Kataoka-Fujiwara ◽

...

Keyword(s):

Fusion Gene ◽

Fusion Partner ◽

Myeloproliferative Disease ◽

Cellular Processes ◽

Partner Gene ◽

Quantitative Changes ◽

High Degree ◽

Deficient Mice

ABSTRACT Septins are evolutionarily conserved GTP-binding proteins that can heteropolymerize into filaments. Recent studies have revealed that septins are involved in not only diverse normal cellular processes but also the pathogenesis of various diseases, including cancer. SEPT6 is ubiquitously expressed in tissues and one of the fusion partner genes of MLL in the 11q23 translocations implicated in acute leukemia. However, the roles of this septin in vivo remain elusive. We have developed Sept6-deficient mice that exhibited neither gross abnormalities, changes in cytokinesis, nor spontaneous malignancy. Sept6 deficiency did not cause any quantitative changes in any of the septins evaluated in this study, nor did it cause any additional changes in the Sept4-deficient mice. Even the depletion of Sept11, a close homolog of Sept6, did not affect the Sept6-null cells in vitro, thus implying a high degree of redundancy in the septin system. Furthermore, a loss of Sept6 did not alter the phenotype of myeloproliferative disease induced by MLL-SEPT6, thus suggesting that Sept6 does not function as a tumor suppressor. To our knowledge, this is the first report demonstrating that a disruption of the translocation partner gene of MLL in 11q23 translocation does not contribute to leukemogenesis by the MLL fusion gene.

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Comparison of Various Vaccines for Inducing Resistance in the Lobster Homarus americanus to the Bacterial Infection, Gaffkemia

Journal of the Fisheries Research Board of Canada ◽

10.1139/f74-246 ◽

1974 ◽

Vol 31 (12) ◽

pp. 1887-1892 ◽

Cited By ~ 16

Author(s):

James E. Stewart ◽

B. M. Zwicker

Keyword(s):

Body Weight ◽

Virulent Strain ◽

Relative Effectiveness ◽

Homarus Americanus ◽

Aerococcus Viridans ◽

Resistance To Infection ◽

High Degree ◽

Cellular Components

Various degrees of resistance to infection of lobsters Homarus americanus by Aerococcus viridans (var.) homari (formerly Gaffkya homari) were induced by vaccines prepared in different ways. Vaccines consisting of formalin-killed cells of a virulent strain of the pathogen (grown in vitro and in vivo) gave a low level of protection, i.e. the vaccinated lobsters were able to resist challenges of 200 bacteria/kg host body weight. A vaccination approach utilizing a low initial dose of the antibiotic, vancomycin, followed 24 h later by injection of 1 × 106 live pathogen cells/kg body weight produced a high degree of resistance to subsequent challenge at times considerably beyond the clearance times for the antibiotic. Fatal infections in normal lobsters are readily established with 10 pathogen cells/kg body weight whereas treatment of lobsters with the vancomycin-live pathogen combination resulted in an LD50 of 2 × 107 live pathogen/kg body weight. It is suggested that the relative effectiveness of the various vaccines is related directly to the concentrations of cellular components within the pathogen, possibly precursors of cell wall mucopeptides.

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Cultured Neural Networks: Optimization of Patterned Network Adhesiveness and Characterization of their Neural Activity

Applied Bionics and Biomechanics ◽

10.1155/2006/251713 ◽

2006 ◽

Vol 3 (1) ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

W. L. C. Rutten ◽

T. G. Ruardij ◽

E. Marani ◽

B. H. Roelofsen

Keyword(s):

Neural Activity ◽

Microelectrode Array ◽

Electrode Site ◽

Local Networks ◽

Planar Substrate ◽

Neural Information ◽

Neural Networks Optimization ◽

High Degree

One type of future, improved neural interface is the “cultured probe”. It is a hybrid type of neural information transducer or prosthesis, for stimulation and/or recording of neural activity. It would consist of a microelectrode array (MEA) on a planar substrate, each electrode being covered and surrounded by a local circularly confined network (“island”) of cultured neurons. The main purpose of the local networks is that they act as biofriendly intermediates for collateral sprouts from thein vivosystem, thus allowing for an effective and selective neuron–electrode interface. As a secondary purpose, one may envisage future information processing applications of these intermediary networks. In this paper, first, progress is shown on how substrates can be chemically modified to confine developing networks, cultured from dissociated rat cortex cells, to “islands” surrounding an electrode site. Additional coating of neurophobic, polyimide-coated substrate by triblock-copolymer coating enhances neurophilic-neurophobic adhesion contrast. Secondly, results are given on neuronal activity in patterned, unconnected and connected, circular “island” networks. For connected islands, the larger the island diameter (50, 100 or 150 μm), the more spontaneous activity is seen. Also, activity may show a very high degree of synchronization between two islands. For unconnected islands, activity may start at 22 days in vitro (DIV), which is two weeks later than in unpatterned networks.

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