Expression and immunolocalization of aquaporins HC-1, -2, and -3 in Cope's gray treefrog, Hyla chrysoscelis.

We have previously identified two aquaporins (HC-1, HC-2) and a glyceroporin (HC-3), homologs, respectively, of mammalian AQP1, AQP2, and AQP3, from the freeze-tolerant treefrog Hyla chrysoscelis. The objective of the present study was to investigate by Western blotting and immunohistofluorescence the expression and localization of these proteins in warm-acclimated, hydrated treefrogs. We hypothesized that patterns of protein expression would reflect unique osmoregulatory roles for the three aquaporins. Western blots revealed a spectrum of protein bands from 28 kDa to 65+ kDa; treatment with N-glycosidase suggested that this reflected variable glycosidation of the aquaporins. HC-1 was expressed in all organs, including dermis of skin, sinusoids and septa of liver, Bowman's capsule of kidney, intestinal lacteal vessels, and perimysium and vasculature of muscle. HC-3 expression was also widespread, but with different localization, including epidermis and dermis of skin, renal collecting ducts, and colonic villous epithelium. HC-2 expression was limited to osmoregulatory organs (renal collecting ducts and epidermis). In many ways, the expression of these proteins paralleled their mammalian homologs. For example, HC-2 and HC-3 expression in collecting ducts appeared similar to the mammalian pattern (the former more apical, the latter more basal). However, some aspects of localization (e.g. HC-1 in Bowman's capsule) were unique, and the ubiquity of HC-3 expression may relate to its facilitation of glycerol transport in this animal that possesses glycerol-dependent freeze tolerance.

Use of gadolinium for carotid artery angiography and stenting in patients with renal insufficiency.

Use of iodinated contrast media (ICM) for angiography can result in contrast-induced nephropathy (CIN). Gadolinium-based contrast media (GCM) have been used in angiography with a goal to reduce the incidence of CIN. We performed a retrospective analysis involving 85 patients with renal insufficiency who underwent 97 carotid artery angiography and stenting (CAAS) procedures with a combination of GCM and ICM. The incidence of peri-procedural death, Q wave myocardial infarction (QWMI), stroke and CIN were recorded. Patients in GCM group had worse preprocedure renal function compared to ICM group. There were no peri-procedural deaths or QWMI in both groups. The incidence of stroke was 2.2% in GCM group and 0% in ICM group. The incidence of CIN were similar in GCM and ICM groups (8.5% vs. 10%, respectively, p NS). However, the predicted risk of CIN was 18.5% for GCM group and 10.4% for ICM group. Use of GCM and ICM combination for CAAS resulted in a 50% reduction in the incidence of predicted CIN risk compared to ICM.

Cavernous hemangioma of the mitral valve: a case report and review of literature.

Cardiac hemangiomas are rare cardiac tumors with fewer than 50 surgically treated cases reported in the literature. Incidence of valvular hemangiomas is extremely low, as cardiac valves are predominantly avascular structures. In this case report, we describe a 33-year-old woman who presented with progressively worsening cardiovascular symptoms. Echocardiography revealed a mitral valve mass for which she underwent surgical resection and mitral valve replacement. Histological examination of the mass revealed cavernous hemangioma of the mitral valve. Postoperative course was uncomplicated, and the patient's symptoms improved after surgery. Surgical excision of valvular hemangiomas appears to be curative in most cases and is the treatment of choice. Periodic echocardiographic follow-up is advised for early detection of tumor recurrence.