CD8dim but not CD8bright cells positive to CD56 dominantly express KIR and are cytotoxic during visceral leishmaniasis

This study reports a structural and functional heterogeneity of CD8⁺CD56⁺NKT cells, which usually decrease quantitatively during visceral leishmaniasis. Based on fluorescence intensity of CD8 receptors on CD56⁺NKT cells, two populations of CD8⁺CD56⁺NKT cells have been identified. These cells were recognized as CD8^dimCD56⁺NKT and CD8^brightCD56⁺NKT cells. We further analyzed the functional nature of CD8^dim and CD8^bright positive CD56⁺NKT cells. In comparison to CD8^brightCD56⁺NKT cells, a significantly higher percentage of CD8^dimCD56⁺NKT cells expressed KIR during VL. The percentage of CD8^dimCD56⁺NKT cells expressing KIR was found 4 fold higher in VL as compared to healthy subjects. But, the difference was insignificant in case of CD8^brightCD56⁺NKT cells. CD8⁺CD56⁺NKT cells release granzyme B to kill the infected cells. A categorical difference was also observed in the function of CD8^dimCD56⁺NKT and CD8^brightCD56⁺NKT cells during visceral leishmaniasis. The percentage of granzyme B expressing CD8^dimCD56⁺NKT cells was 2.83 fold higher in VL compared to healthy subjects. But, there was no significant difference in granzyme B expressing CD8^brightCD56⁺NKT cells in samples from healthy and VL subjects. However, within VL subject, the percentage of granzyme B expressing CD8^dimCD56⁺NKT cells was 5.7 fold higher in comparison to CD8^brightCD56⁺NKT cells. This study concludes that CD8^dimCD56⁺NKT cells are more cytotoxic than CD8^brightCD56⁺NKT cells during VL.     

Reproductive toxicity of Aroclor-1254: Effects on oocyte, spermatozoa, in vitro fertilization, and embryo development in the mouse

Polychlorinated biphenyls (PCBs) have been reported to adversely affect reproduction in laboratory and wild animals. The present study was undertaken to determine the toxic potential of Aroclor-1254 (A-1254) on in vitro fertilizing ability of oocytes and epididymal sperm and on preimplantation embryo development in the mouse. A-1254 was added to the IVF medium at concentrations of 0.01, 0.1, 1.0, and 10.0 μg/mL. Cumulus masses containing the oocytes were obtained from superovulated B6D2F1 mice and were placed in the culture medium containing A-1254 to which epididymal sperm, capacitated in a medium without A-1254, were added. The IVF rate was assessed 20 to 24 h after insesemination. A-1254 significantly reduced the mean percent ova fertilized even at 0.1 μg/mL. Incubation of the cumulus masses in various concentrations of A-1254 for 6 h, followed by insemination with sperm capacitated in the presence of A-1254, also significantly reduced the IVF rate. Capacitation of sperm in A-1254-containing medium, followed by co-culture with untreated oocytes, failed to affect the IVF rate. No significant effect on sperm motility was observed following exposure to 1 and 10 μg/mL of A-1254. Estradiol-17 β also reduced the IVF rate, however, the effect of A-1254 was more severe compared to the estradiol treatment. Furthermore, addition of A-1254 to the embryo culture medium was associated with a significant decrease in embryo growth at 48 h and 96 h. These results demonstrate adverse effects of A-1254 on oocytes, IVF, and embryonic development in the mouse.     

The impact of hydration on renal measurements and on cortical echogenicity in children

Background

Kidney ultrasonography is frequently performed in children; to date there are no specific guidelines regarding hydration before the examination.

Objective

Because certain renal measurements can be indicative of pathology, we used sequential US images to investigate the effect of standardised hydration in children relative to renal size, echogenicity and pelvic expansion.

Materials and methods

Thirty-one children (7 years to 14 years old) underwent US examinations before hydration (T0) and at 30 min (T30) and 60 min (T60) after ingesting water. We measured bladder volume, inter-polar kidney size, renal volume and anterior-posterior diameter of the pelvis. Cortical echogenicity was compared to that of the liver and spleen.

Results

On the right side the increase in average inter-polar renal size was 2.5% at T30 and 2.6% at T60 (P?<?0.05) compared to T0. On the left the increase was 3.8% at T30 and 4.3% at T60 (P?<?0.05). Volume expansion for the right kidney was 16.8% at T30 and 14.0% at T60 (P?<?0.05). On the left it was 12.9% at T30 and 10.2% at T60 (P?<?0.05). Cortical echogenicity progressed from hypoechogenicity to isoechogenicity (P?<?0.05). The percentage of expanded pelves increased with hydration (T0: 3.2%, T30: 9.7%, T60: 22.6%).

Conclusion

Oral hydration influences renal length, volume and echogenicity in children. Hydration results in expansion of the pelvis. We recommend standardisation of hydration before US examination.