Lecithin nanoparticles enhance the cryosurvival of caprine sperm.

This study was designed to compare the effects on goat spermatozoa cryosurvival of nano-lecithin-based (NL), lecithin-based (L) and egg yolk-based (EY) extenders. Ejaculates were collected from four fertile goats using artificial vagina and diluted with nine extenders. NL and L were tested at concentrations 1%, 2%, 3% and 4% (w/v), versus 15% (v/v) egg yolk-based extender. Overall, sperm quality (higher motility, viability and HOST, and lower apoptosis) was higher for NL than for L treatments (P < 0.05 for most cases, except for 1%). NL at 1% and especially at 4% showed lower motility and viability than 2% or 3% NL. NL at 2% achieved a better performance (P < 0.05) than EY for VCL (131.5 ±â€¯1.3 vs. 120.3 ±â€¯1.9 µm/s), VSL (43.9 ±â€¯1.5 vs. 35.8 ±â€¯1.4 µm/s), LIN (35.7 ±â€¯0.6 vs. 29.3 ±â€¯0.8%), WOB (47.0 ±â€¯0.5 vs. 43.9 ±â€¯0.9%) and viability (66.4 ±â€¯1.7 vs. 52.7 ±â€¯1.9%). Late apoptotic spermatozoa were also lower in 2% NL compared to EY (16.0 ±â€¯0.5 vs. 26.3 ±â€¯1.1%, P < 0.001). EY and 2% NL were compared in an IVF trial, with no significant differences in cleavage (68.8 vs. 70.8%) or blastocyst ratios (21.3 vs. 20.8%). In conclusion, using 2% nanolecithin in semen dilution could improve sperm cryosurvival of goat.

The effect of methamphetamine on an animal model of erectile function.

In the US methamphetamine is considered a first-line treatment for attention-deficit hyperactivity disorder. It is also a common drug of abuse. Reports in patients and abusers suggest its use results in impotence. The efficacy of phosphodiesterase-5 inhibitors (PDE5i) to restore erectile function in these patient groups also has not been determined. In these studies, we determined if the rat is a suitable animal model for the physiological effects of methamphetamine on erectile function, and if a PDE5i (tadalafil) has an effect on erectile function following methamphetamine treatment. In acute phase studies, erectile function was measured in male Sprague-Dawley rats, before and after administration of 10 mg/kg methamphetamine i.p. Chronically treated animals received escalating doses of methamphetamine [2.5 mg/kg (1st week), 5 mg/kg (2nd week), and 10 mg/kg (3rd week)] i.p. daily for 3 weeks and erectile function compared with untreated controls. The effect of co-administration of tadalafil was also investigated in rats acutely and chronically treated with methamphetamine. Erectile function was determined by measuring the intracorporal pressure/blood pressure ratio (ICP/BP) following cavernous nerve stimulation. In both acute and chronic phase studies, we observed a significant increase in the rates of spontaneous erections after methamphetamine administration. In addition, following stimulation of the cavernous nerve at 4 and 6 mA, there was a significant decrease in the ICP/BP ratio (approximately 50%), indicative of impaired erectile function. Tadalafil treatment reversed this effect. In chronically treated animals, the ICP/BP ratio following 4 and 6 mA stimulation decreased by approximately 50% compared with untreated animals and erectile dysfunction (ED) was also reversed by tadalafil. Overall, our data suggest that the rat is a suitable animal model to study the physiological effect of methamphetamine on erectile function. Our work also provides a rationale for treating patients that report ED associated with therapeutics-containing methamphetamine or amphetamine with PDE5i.

Gene transfer with a vector expressing Maxi-K from a smooth muscle-specific promoter restores erectile function in the aging rat.

Previous reports have demonstrated that gene transfer with the alpha, or pore-forming, subunit of the human Maxi-K channel (hSlo) restores the decline in erectile capacity observed in established rat models of diabetes and aging. Preliminary data from a human clinical trial also showed safety and potential efficacy in 11 men treated with the same plasmid construct expressing the Maxi-K channel. In all instances, the original plasmid was driven by the heterologous cytomegalovirus promoter which is broadly active in a wide variety of cell and tissue types. To more precisely determine the contribution of the corporal myocyte to the observed physiological effects in vivo, we report here our initial work using a distinct vector (pSMAA-hSlo) in which hSlo gene expression was driven off the mouse smooth muscle alpha-actin (SMAA) promoter. Specifically, older rats, with diminished erectile capacity, were given a single intracorporal injection with either 100 mug pVAX-hSlo or 10, 100 or 1000 mug pSMAA-hSlo, or vector or vehicle alone. Significantly increased intracavernous pressure (ICP) responses to cavernous nerve stimulation were observed for all doses of both plasmids encoding hSlo, relative to control injections. These data confirm and extend previous observations to document that smooth muscle cell-specific expression of hSlo in corporal tissue is both necessary and sufficient to restore erectile function in aging rats.

Ageing causes cytoplasmic retention of MaxiK channels in rat corporal smooth muscle cells.

The MaxiK channel plays a critical role in the regulation of corporal smooth muscle tone and thereby erectile function. Given that ageing results in a decline in erectile function, we determined changes in the expression of MaxiK, which might impact erectile function. Quantitative-polymerase chain reaction demonstrated that although there is no significant change in transcription of the alpha- and beta-subunits that comprise the MaxiK channel, there are significant changes in the expression of transcripts encoding different splice variants. One transcript, SV1, is 13-fold increased in expression in the ageing rat corpora. SV1 has previously been reported to trap other isoforms of the MaxiK channel in the cytoplasm. Correlating with increased expression of SV1, we observed in older rats there is approximately a 13-fold decrease in MaxiK protein in the corpora cell membrane and a greater proportion is retained in the cytoplasm (approximately threefold). These experiments demonstrate that ageing of the corpora is accompanied by changes in alternative splicing and cellular localization of the MaxiK channel.

Transient myeloproliferative disease of the newborn: case report with placental, cytogenetic, and flow cytometric findings.

Transient myeloproliferative disease (TMD) of the newborn is a rare hematologic abnormality associated with trisomy 21. It is frequently difficult to distinguish the disorder from true congenital leukemia (TCL). Unlike leukemia, which has a clinically aggressive course, TMD generally resolves within weeks to months. We present a case of TMD of the newborn diagnosed on the basis of peripheral blood studies and describe the pertinent pathological findings within the placenta. Flow cytometric analysis of the blasts in the peripheral blood showed phenotypic heterogeneity with features consistent with megakaryocytic differentiation. Cytogenetic studies showed trisomy 21 within the blastic cells. The placenta showed villous dysmaturity with associated chorangiosis and prominent intravascular aggregates of primitive-appearing cells with focal, early vascular wall invasion. The neonate recovered fully and shows no evidence of disease at 2 years of age.

An unusual case of metastatic intracardiac plasmacytoma.

The authors report the case of a 36-year-old male who, following investigations for dyspnea, othopnea and peripheral cyanosis, was found to have metastatic intracardiac plasmacytoma. Diagnosis was made initially with transesophageal echocardiography and emergent cardiac surgery was performed. Postoperative transthoracic and transesophageal echocardiograms revealed residual masses in the right and left atrium. The patient was subsequently treated with systemic chemotherapy and was symptom-free within three months of treatment, with rapid decline of paraproteins in the serum and urine. This case of intracardiac metastatic plasmacytoma is deemed unique because cardiac involvement with multiple myeloma has not been studied in detail, largely due to the rarity of such a presentation.