In secretory cells, osmotic swelling of secretory granules is proposed to be an intermediate step in exocytic fusion of the granules with the plasma membrane. For osmotic swelling of the granule, a H (+) gradient generated by vacuolar-type H (+) -ATPase (V-ATPase) may be a driving force for accumulation of K (+) via its exchange with H (+) , concurrent with accumulation of Cl (-) and H(2)O. Her...

MTT (3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay is commonly used to validate the viability of metabolically active cells. The study was conducted to examine and validate the MTT test to assess the sperm viability of Nili-Ravi buffalo bulls and compare the efficiency of the test with the supra-vital staining technique (eosin-nigrosine) and hypo-osmotic swelling test. F...

As an attempt to find an inexpensive and simple laboratory method for artificial insemination (AI) bull semen quality assessment, the osmotic resistance of spermatozoa was measured using the hypoosmotic swelling (HOS) test, developed by Jeyendran et al. (1984) (labelled HOS-1), and its modifications (HOS-2, HOS-3), with decreased osmotic pressure aimed at challenging sperm survival ability. The...

Introduction Cartilage is a complex tissue whose extracellular matrix mainly consists of charged proteoglycan (PG) assemblies imbedded in a fibrous collagen network. PGs attract water and repel each other due to their negative charges generating a high swelling pressure. Collagens are proteins that form the fibrillar meshwork providing cartilage with its tensile strength. Cartilage extracellula...

Motivated by biological protocols that require transfer of large pieces of DNA into cells, we here review several aspects of osmotic swelling and lysis of semipermeable unilamellar vesicles. Swelling involves a continuous phase transition from a fluctuating flaccid state to a maximum volume turgid state, without a divergent correlation length and with exponents that violate the hyperscaling rel...

In order to find an optimal hypo-osmotic swelling test (HOST) and to identify viable sperm cells from patients with asthenozoospermia for intracytoplasmic sperm injection (ICSI), we tested single motile and non-motile spermatozoa in four hypo-osmotic solutions by micromanipulation. The four solutions were: A, H2O; B, 50 mOsm NaCl; C, 150 mOsm NaCl and D, 150 mOsm sodium citrate and fructose. Eo...

Tissue behavior is governed to a large extent by composition and microstructure of the extracellular matrix. In cartilage, various biopolymers (glycosaminoglycans, collagen, hyaluronic acid, etc.) are integrated into a complex network that imparts the tissue with its low-friction characteristics and load-bearing capacity. The structure of collagen (predominantly type II collagen) gives it tensi...

Polyelectrolyte gels are known to undergo significant conformational changes in response to external stimuli such as pH, temperature, or the dielectric constant. Specifically, an increase of the degree of ionization associated with an increasing number of counterions leads to swelling of the network. For a macroscopically large gel, which is electrostatically neutral in its interior, swelling i...

Mitochondria dominate the process of life-and-death decisions of the cell. Continuous generation of ATP is essential for cell sustenance, but, on the other hand, mitochondria play a central role in the orchestra of events that lead to apoptotic cell death. Changes of mitochondrial volume contribute to the modulation of physiological mitochondrial function, and several ion permeability pathways ...

Tissue damage activates cytosolic phospholipase A2 (cPLA2), releasing arachidonic acid (AA), which is oxidized to proinflammatory eicosanoids by 5-lipoxygenase (5-LOX) on the nuclear envelope. How tissue damage is sensed to activate cPLA2 is unknown. We investigated this by live imaging in wounded zebrafish larvae, where damage of the fin tissue causes osmotic cell swelling at the wound margin ...