Novel Fast and Reliable Method for Nano-Erythrosome Production Using Shear Force.

Purpose: The production of nano-erythrosomes (NEs) by extrusion, which is considered the "gold standard", has several disadvantages such as difficult equipment assembly, long procedure time, variable pressure, and problems with sterility. An alternative approach, using ultrasound probe, has been shown to overheat the sample and have suboptimal results compared to the extrusion method. In our study, we propose, develop, and test a new method for the fabrication of NEs based on shear force and then compare it to the "gold standard" extrusion approach.

Unexpectedly decreased plasma cytokines in patients with chronic back pain.

Introduction: Chronic back pain is one of the most important socioeconomic problems that affects the global population. Elevated levels of inflammatory mediators, such as cytokines, have been correlated with pain, but their role in chronic back pain remains unclear. The effectiveness of anti-inflammatory drugs seems to be limited for chronic back pain.

VEGF vascularization pathway in human intervertebral disc does not change during the disc degeneration process.

Objective: During degeneration of the intervertebral disc ingrowth of blood vessels and nerves into the disc are associated with back pain. Vascular endothelial growth factors promote vasculogenesis by binding to the membrane vascular endothelial growth factor receptor 1, while shorter soluble forms of this receptor can inhibit vascularization. We hypothesized that membrane and soluble receptor forms might change between stages of intervertebral disc degeneration.

An in vitro expansion score for tissue-engineering applications with human bone marrow-derived mesenchymal stem cells.

Human bone marrow-derived mesenchymal stem cells (MSCs) have limited growth potential in vitro and cease to divide due to replicative senescence, which from a tissue-engineering perspective has practical implications, such as defining the correct starting points for differentiation and transplantation. Time spent in culture before the loss of required differentiation potential is different and reflects patient variability, which is a problem for cell expansion. This study aimed to develop a score set which can be used to quantify the senescent state of MSCs and predict whether cells preserve their ability to differentiate to osteogenic, adipogenic and chondrogenic phenotypes, based on colony-forming unit (CFU) assay, population doubling time (PDT), senescence-associated β-galactosidase (SA-β-Gal) activity, cell size, telomere length and gene expression of MSCs cultured in vitro over 11 passages.

BMP-2 and TGF-β3 do not prevent spontaneous degeneration in rabbit disc explants but induce ossification of the annulus fibrosus.

Introduction: Different approaches for disc regeneration are currently under investigation. Beside gene therapy and tissue engineering techniques, the application of growth and differentiation factors own promising potential. Studies using reduced intervertebral disc models, such as cell or tissue fragment cultures, have limited validity and show controversial results depending on the employed experimental model.

The copper-inducible ComR (YcfQ) repressor regulates expression of ComC (YcfR), which affects copper permeability of the outer membrane of Escherichia coli.

The pathway of copper entry into Escherichia coli is still unknown. In an attempt to shed light on this process, a lux-based biosensor was utilized to monitor intracellular copper levels in situ. From a transposon-mutagenized library, strains were selected in which copper entry into cells was reduced, apparent as clones with reduced luminescence when grown in the presence of copper (low-glowers).

Influence of different commercial scaffolds on the in vitro differentiation of human mesenchymal stem cells to nucleus pulposus-like cells.

Introduction: Cell-based therapies for regeneration of the degenerated intervertebral disc (IVD) are an alternative to current surgical intervention. Mesenchymal stem cells (MSCs), in combination with a scaffold, might be ideal candidates for regenerating nucleus pulposus (NP), the pressure-distributing part of the IVD. While the use of growth factors for MSCs differentiation currently receives major attention, in this study we compare the performance of sponge-like matrixes in supporting cell differentiation into NP-like cells.

The in vitro effects of dexamethasone, insulin and triiodothyronine on degenerative human intervertebral disc cells under normoxic and hypoxic conditions.

Degeneration of intervertebral discs (IVD) is one of the main causes of back pain and tissue engineering has been proposed as a treatment. Tissue engineering requires the use of highly expensive growth factors, which might, in addition, lack regulatory approval for human use. In an effort to find readily available differentiation factors, we tested three molecules--dexamethasone, triiodothyronine (T3) and insulin--on human IVD cells isolated after surgery, expanded in vitro and transferred into alginate beads.

Human mesenchymal stem cell co-culture modulates the immunological properties of human intervertebral disc tissue fragments in vitro.

The capacity of mesenchymal stem cells (MSCs) to differentiate into intervertebral disc (IVD)-like cells has been well described, but their ability to modulate the inflammatory processes in the IVD remains unclear. We found that tissue obtained by discectomy of degenerated and post-traumatic IVD contains significant amounts of IgG antibodies, a sign of lymphocyte infiltration. Further we investigated whether MSCs in vitro, which were characterized for their multilineage differentiation potential and may have immunomodulatory effects on IVD fragments.

The stress response protein Gls24 is induced by copper and interacts with the CopZ copper chaperone of Enterococcus hirae.

Intracellular copper routing in Enterococcus hirae is accomplished by the CopZ copper chaperone. Under copper stress, CopZ donates Cu(+) to the CopY repressor, thereby releasing its bound zinc and abolishing repressor-DNA interaction. This in turn induces the expression of the cop operon, which encodes CopY and CopZ, in addition to two copper ATPases, CopA and CopB.

Apoptosis and gene expression of collagenases but not gelatinases in rabbit disc fragment cultures.

Object: The object of this study was to characterize the biological response of isolated intervertebral disc fragments to in vitro culture conditions with respect to cell death and inflammatory and catabolic changes. The acquired data could help to gain a better understanding of the biological reaction of disc tissue when exposed to environmental changes along with altered nutritional and osmotic conditions, as are encountered in different in vitro disc models or disc diseases in vivo.

Methods: Intervertebral disc anulus fragments were isolated from Burgundy rabbits and cultured in standard media for 3 days.

Vertebral endplate trauma induces disc cell apoptosis and promotes organ degeneration in vitro.

There is a major controversy whether spinal trauma with vertebral endplate fractures can result in post-traumatic disc degeneration. Intervertebral discs, which are adjacent to burst endplates, are frequently removed and an intercorporal spondylodesis is performed. In any case, the biological effects within the discs following endplate fractures are poorly elucidated to date.

Establishment of a novel intervertebral disc/endplate culture model: analysis of an ex vivo in vitro whole-organ rabbit culture system.

Study Design: Ex vivo in vitro study evaluating a novel intervertebral disc/endplate culture system.

Objectives: To establish a whole-organ intervertebral disc culture model for the study of disc degeneration in vitro, including the characterization of basic cell and organ function.

Summary Of Background Data: With current in vivo models for the study of disc and endplate degeneration, it remains difficult to investigate the complex disc metabolism and signaling cascades.

Influence of diurnal hyperosmotic loading on the metabolism and matrix gene expression of a whole-organ intervertebral disc model.

It is generally agreed that the mechanical environment of intervertebral disc cells plays an important role in maintaining a balanced matrix metabolism. The precise mechanism by which the signals are transduced into the cells is poorly understood. Osmotic changes in the extracellular matrix (ECM) are thought to be involved.

Interaction kinetics of the copper-responsive CopY repressor with the cop promoter of Enterococcus hirae.

In Enterococcus hirae, copper homeostasis is controlled by the cop operon, which encodes the copper-responsive repressor CopY, the copper chaperone CopZ, and two copper ATPases, CopA and CopB. The four genes are under control of CopY, which is a homodimeric zinc protein, [Zn(II)CopY]2. It acts as a copper-responsive repressor: when media copper is raised, CopY is released from the DNA, allowing transcription to proceed.

Measurement of cytoplasmic copper, silver, and gold with a lux biosensor shows copper and silver, but not gold, efflux by the CopA ATPase of Escherichia coli.

Copper, silver, gold and other heavy metals are potentially toxic to cells. Copper is also essential and cellular levels must be carefully controlled. In contrast, there is no known biological role for silver or gold and they have not been recognized as metals that are under homeostatic control.

Copper homeostasis in Enterococcus hirae.

Copper is an essential component of life because of its convenient redox potential of 200-800 mV when bound to protein. Extensive insight into copper homeostasis has only emerged in the last decade and Enterococcus hirae has served as a paradigm for many aspects of the process. The cop operon of E.

The MerR family of transcriptional regulators.

The MerR family is a group of transcriptional activators with similar N-terminal helix-turn-helix DNA binding regions and C-terminal effector binding regions that are specific to the effector recognised. The signature of the family is amino acid similarity in the first 100 amino acids, including a helix-turn-helix motif followed by a coiled-coil region. With increasing recognition of members of this class over the last decade, particularly with the advent of rapid bacterial genome sequencing, MerR-like regulators have been found in a wide range of bacterial genera, but not yet in archaea or eukaryotes.

The Escherichia coli copper-responsive copA promoter is activated by gold.

The copA gene of Escherichia coli encodes a copper transporter and its promoter is normally regulated by Cu(I) ions and CueR, a MerR-like transcriptional activator. We show that CueR can also be activated by gold salts and that Cys(112) and Cys(120) are involved in recognition of gold, silver, and copper salts. Gold activation is unaffected by copper chelating agents but is affected by general metal chelators.

The Pco proteins are involved in periplasmic copper handling in Escherichia coli.

The interactions between the plasmid-borne copper resistance determinant, pco, and the main copper export system in Escherichia coli have been investigated and no direct interaction has been found. The PcoE and PcoC proteins are periplasmic and PcoC binds one Cu ion per protein molecule. PcoA is also periplasmic and can substitute for the chromosomally encoded CueO protein.