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S Raty

Publications and source records attributed to S Raty.

3 recordsLinked to original sources

Microfluidic technology for assisted reproduction.

The physical tools used in assisted reproduction have changed little over several decades. Microfluidics is an emerging technology that allows a fresh examination of the way assisted reproduction is performed. Here we review our work to develop microfluidic devices to perform the functions required in assisted reproduction. These functions include loading/unloading, culture, chemical manipulation, and mechanical manipulation of embryos and oocytes. Basic microfluidic theory and microfluidic device design and operation are discussed. Results are presented for mechanical removal of cumulus cells and for embryo culture. Results suggest that microfluidic systems will lead to improved efficiencies in assisted reproduction.

Animals↗

Effect of decreased glucose concentration on cerebrovascular tone in vitro.

We studied the effect of decreased glucose concentration on cerebrovascular tone in vitro. Segments of rat middle cerebral arteries (MCA) were isolated, cannulated at both ends with glass micropipettes, and pressurized to 85 mm Hg. Decreasing the glucose in the extraluminal bath and luminal perfusate from 5.5 mmol/L to 1.0 or 0.5 mmol/L for 1.5 hours each had no significant effect on the diameter of the arteries. When all the glucose was removed from the extraluminal bath and luminal perfusate for 1.5 hours, the MCA dilated by 23% [252 +/- 24 (SD) microns to 311 +/- 7 microns (P < .5, n = 7)]. This dilation was 80% of the maximum dilation produced by removal of Ca+2 from the bathing solutions. Neither removal of the endothelium nor inhibition of the ATP-sensitive K channels with 10(-5) mol/L glibenclamide altered the response of the isolated MCA to the removal of glucose. We conclude that rat MCA are relatively more resistant to substrate limitation compared to the brain as a whole.

ATP-Binding Cassette Transporters↗

Intraoperative jugular desaturation during surgery for traumatic intracranial hematomas.

Traumatic intracranial hematomas which are present on hospital admission or which develop during the hospital course are associated with a worse neurological outcome than diffuse injuries. The purpose of this study was to monitor jugular venous oxygen saturation (Sjvo2) during surgery for evacuation of traumatic intracranial mass lesions, to determine the incidence and the causes of jugular venous desaturation, and to assess the usefulness of Sjvo2 monitoring in this setting. Twenty-five severely head injured patients were monitored during 27 surgical procedures. At the start of the surgical procedure, the median Sjvo2 was 47% (range 25%-89%). Seventeen (63%) of the patients had a Sjvo2 less than 50%. Five patients had extremely low Sjvo2 values (< or = 30%). Upon evacuation of the intracranial hematoma, there was a significant (P < 0.001) increase in the median Sjvo2 to 65% (range 50%-88%). Intracranial hypertension was the primary cause of the low Sjvo2, as confirmed by the response to surgical evacuation. Hypotension (mean arterial pressure < 80 mm Hg) was a contributing factor in seven of the cases of jugular desaturation. The definitive treatment of a traumatic intracranial hematoma is surgical evacuation. However, during the period prior to evacuation of the hematoma, jugular venous desaturation was common, suggesting that monitoring Sjvo2 might provide useful information about the adequacy of cerebral perfusion.

Adult↗