Nitric oxide (NO) released in response to hypoxia-ischemia (HI) in the newborn brain may mediate both protective and pathologic responses. We sought to determine whether pharmacologic increase of NO using an NO donor would reduce neurologic injury resulting from HI in the postnatal day 7 rat. We measured NO levels and CBF in the presence of either a NOS inhibitor, N-nitro-L-arginine methyl ester (L-NAME) or an NO donor (. Both inhibition of NOS and administration of an NO donor reduced neuropathologic injury after 7-day recovery. NO levels decreased in both ischemic and contralateral hemispheres during HI. This response was prevented by treatment with DETANONOate. Despite the decrease in NO, CBF increased during ischemia in the contralateral hemisphere but decreased when combined with brief hypoxia. Treatment with L-NAME abolished these increases, which were not altered by DETANONOate. Reduction of cellular metabolism by mild hypothermia also reduced both NO and CBF. Following prolonged HI, CBF remained decreased in the ischemic hemisphere up to 24-hour recovery. This decrease was prevented by treatment with DETANONOate. These data show that administration of an NO donor reduces neurologic injury following HI in the newborn rat. This mechanism of this protection, in part, is due to an increase in the rate of recovery of CBF compared to vehicle-treated animals. Augmentation of NO-dependent increases in CBF may serve to improve neurologic outcome after perinatal asphyxia.

Background: The majority of cervical cytology specimens are being collected in liquid-based preservatives (LBP). However, the assessment of specimen adequacy, as mandated by The Bethesda System (TBS), is still being performed at the time of slide review. We present a rapid, flow cytometric method for assessing specimen adequacy.

The purpose of this pictorial essay is to describe magnetic resonance (MR) imaging features of acute processes involving the bowel. While computed tomography (CT) is likely to remain the modality of choice in this setting, the advantages of MR include high soft tissue contrast, lack of ionizing radiation, and the ability to administer gadolinium in patients with a history of allergic reaction to iodinated contrast material. With the increasing utilization of abdominal/pelvic MR, radiologists must recognize the MR features of acute bowel pathology. Key MR findings of a variety of causes of acute abdominal pain are illustrated.