Effects of unconjugated gold, silver and titanium dioxide nanoparticles on bovine spermatozoa at various stages of cryopreservation.

BACKGROUND: The increasing use of nanoparticles (NP) for gender-selected spermatozoa, sperm-enriched semen and novel extenders raises the concern of undesirable effects on fertility and sperm function. OBJECTIVE: To investigate the effects of gold (Au-), silver (Ag-), and titanium dioxide (TiO2-) NPs on the motility and sperm functions in bovine spermatozoa at various stages of cryopreservation. MATERIALS AND METHODS: Frieswal (Sahiwal × Holstein Friesian) bull semen ejaculates (N = 24) were challenged with unconjugated and ligand-free Au-, Ag-, and TiO2-NPs. RESULTS: At post-dilution (fresh) stage, there was no significant difference observed in progressive motility and viability amongst the control and any nanoparticle-treated groups, though plasma membrane integrity was significantly reduced in nanoparticle-treated groups (p < 0.05). The acrosome intactness was also significantly reduced in the groups of Ag-NP and TiO2 -NP (p < 0.05), while there was no effect observed in the Au-NP group. At post-equilibration stage, a significant reduction in motility, viability, and plasma membrane integrity was observed in all three nanoparticle-treated groups (p < 0.05). There was no difference in intact acrosome between the control and Au-NPs groups; which was significantly higher than the Ag-NP and TiO2 -NP groups (p < 0.05). At post-thaw stage, all NP groups resulted in a significant reduction of motility, viability, acrosome intactness and plasma membrane integrity (p < 0.05). Besides, TiO2-NPs appear to be significant more toxic (p < 0.05) among three NP groups, and Au-NPs appear to be lesser toxic. CONCLUSION: Bovine spermatozoa are adversely affected by Au-, Ag- and TiO2 -NPs that may impair sperm motility and other functions. doi.org/10.54680/fr22310110512.

The N-terminal segment of glyceraldehyde-3-phosphate dehydrogenase of Haemonchus contortus interacts with complements C1q and C3.

Haemonchus contortus, an economically important blood-sucking parasite of sheep and goats, survives the harsh host gut environment by secreting a number of proteins referred as excretory/secretory (ES) products. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a glycolytic enzyme, is one of the components of H. contortus ES products. The parasite enzyme binds to complement C3 and inhibits its activity. In this study, the C3-binding activity of the parasite GAPDH was mapped to the N-terminal part of the enzyme by generating defined recombinant fragments of the protein. The N-terminal fragment also trapped complement C1q but not C5 and inhibited complement-mediated lysis of sensitized sheep erythrocytes. Competitive binding assay indicates different binding regions for C1q and C3 proteins. GAPDH stimulated proliferation of goat peripheral blood mononuclear cells in vitro and reacted with the sera from H. contortus-infected animals. However, the fragments of GAPDH did not stimulate cell proliferation nor reacted with the infected animal sera. Furthermore, denatured GAPDH failed to react with the infected animal sera in dot blot suggesting conformation-dependent epitope. These results demonstrate an elegant strategy of the parasite to completely shut down complement activation and identify GAPDH as a promising target for future therapeutic intervention.

Glyceraldehyde-3-phosphate dehydrogenase of the parasitic nematode Haemonchus contortus binds to complement C3 and inhibits its activity.

Haemonchus contortus is an economically important gastrointestinal parasite that infects primarily sheep and goats. To survive inside the host, the parasite must overcome the host immune response. In this study, we have identified and characterized a complement-C3-binding protein (H.c-C3BP) from this parasite employing biochemical and molecular biology tools. Initially, a truncated form of the protein was isolated from the excretory-secretory products of the parasite using C3-Sepharose column that facilitated its identification by mass spectroscopy. Subsequently, the parent molecule was generated in E. coli, and sequence analysis confirmed it as glyceraldehyde-3-phosphate dehydrogenase (GAPDH). GAPDH reacted with the antiserum raised against the truncated protein, and the truncated protein reacted with anti-GAPDH antiserum. The protein inhibited complement function as measured by haemolytic assay and membrane attack complex (MAC) formation. Sera from H. contortus-infected animals reacted with GAPDH as well as the truncated form of the protein, which further lend support to protein secretion. Thus, the C3-binding property of H. contortus GAPDH is a new function, and it represents a new entity of complement-binding protein. Identification and characterization of H.c-C3BP should facilitate development of new therapeutics considering a key role of this protein in immune modulation.

Tension pneumoventricle following exposure of shunt chamber.

Pneumocephalus is the presence of air within the intracranial vault. Intraventricular pneumocephalus, also known as pneumoventricle is relatively rare and commonly occurs following cerebrospinal fluid diversion procedures. This may occur immediately or be delayed. Although a small amount of pneumoventriculus is asymptomatic and may not require any treatment, when present under tension it needs to be evacuated. We present a case of tension pneumoventricle following exposure of the shunt chamber, which resulted in deterioration of the patients' neurological condition and required evacuation.

Benign triton tumor of the trigeminal nerve.

Benign triton tumor (neuromuscular hamartoma) is a rare tumor of the peripheral nerves, comprising mature neural and striated muscle elements. We report the third case, according to the literature, of a benign triton tumor affecting the Vth cranial nerve in a 4-year-old male child. The tumor was seen to involve the mandibular division of the trigeminal nerve in the infratemporal fossa and extend intracranially by eroding the base of middle cranial fossa. The mass was totally excised. In the tumor, bundles of axons intermingling with fascicles of relatively mature skeletal muscle were found. This type of hamartomatous lesions of neuroectodermal-mesenchymal origin could have arisen as the result of incorporation of mesenchymal tissue into nerve sheaths during embryogenesis or aberrant differentiation of neuroectodermal component into mesenchymal elements.

An epidemic of rotavirus diarrhoea in Manipur, India.

Recurrent epidemics of acute diarrhoeal disease in young children have occurred during the winter months in Manipur (India) for many years. During November 1979, children admitted to hospital for acute diarrhoea were investigated and, in addition to pathogenic Escherichia coli and Shigella rotovirus was detected by ELISA in a number of stool samples, especially of those less than one year old. The importance of this finding and the need for further study are discussed.