Abstract-Recent studies have shown that the heme oxygenase (HO) product, carbon monoxide (CO), induces vasodilation and that inhibition of HO produces a sustained hypertension in rats. Given the importance of renal medullary blood flow (MBF) in the long-term control of arterial blood pressure, we hypothesized that the HO/CO system may play an important role in maintaining the constancy of blood flow to the renal medulla, which in turn contributes to the antihypertensive effects of the renal medulla. To test this hypothesis, we first determined the expression of 2 isoforms of HO (HO-1 and HO-2) in the different kidney regions. By Northern blot analyses, the abundance of both isozyme mRNAs was found highest in the renal inner medulla and lowest in the renal cortex. The transcripts for HO-1 in the renal outer medulla and inner medulla were 2.5 and 3.7 times that expressed in the renal cortex and those for HO-2 in the outer medulla and inner medulla were 1.3 and 1.6 times that expressed in the renal cortex, respectively. Western blot analyses of both enzymes showed the same expression pattern in these kidney regions as the mRNAs. To determine the role that HO plays in the control of renal MBF, we examined the effect of the HO inhibitor zinc deuteroporphyrin 2,4-bis glycol (ZnDPBG) on cortical blood flow and MBF in anesthetized rats. ZnDPBG was given by renal medullary interstitial infusion, and cortical blood flow and MBF were measured by laser Doppler flowmetry. Renal medullary interstitial infusion of ZnDPBG at a dose of 60 nmol/kg per minute produced a 31% decrease in MBF over a period of 60 minutes as measured by laser Doppler flow signal (0.62Ϯ0.02 vs 0.43Ϯ0.04 V in control vs ZnDPBG). With the use of an in vivo microdialysis technique, ZnDPBG was found to significantly reduce renal medullary cGMP concentrations when infused into the renal medullary interstitial space. These results suggest that both HO-1 and HO-2 are highly expressed in the renal medulla, that HO and its products play an important role in maintaining the constancy of blood flow to the renal medulla, and that cGMP may mediate the vasodilator effect of HO products in the renal medullary circulation.

There is an increasing need for new strategies to improve the heating efficiency or the specific absorption rate (SAR) of magnetite (Fe O ), which is the only FDA approved magnetic material. We propose a facile approach to obtain well-dispersed highly crystalline Fe O nanorods (NRs) by the reduction of β-FeOOH in an organic solvent and demonstrate that the SAR of Fe O NRs can be enhanced by tuning their aspect ratios. Fe O NRs with an aspect ratio of 4.5 have a much higher SAR as compared with 15 nm Fe O nanoparticles and Fe O NRs counterparts with an aspect ratio of 10. The highest SAR is greatly increased up to 1072 W g for an ac field of 33 kA m and a concentration of 5 mg mL , which is mostly attributed to hysteresis losses. These findings pave a new pathway for the design and synthesis of novel anisotropic iron oxide nanostructures with an optimal heating efficiency for advanced hyperthermia.

Pulsatilla (Ranunculaceae) consists of about 40 species, and many of them have horticultural and/or medicinal value. However, it is difficult to recognize and identify wild Pulsatilla species. Universal molecular markers have been used to identify these species, but insufficient phylogenetic signal was available. Here, we compared the complete chloroplast genomes of seven Pulsatilla species. The chloroplast genomes of Pulsatilla were very similar and their length ranges from 161,501 to 162,669 bp. Eight highly variable regions and potential sources of molecular markers such as simple sequence repeats, large repeat sequences, and single nucleotide polymorphisms were identified, which are valuable for studies of infra- and inter-specific genetic diversity. The SNP number differentiating any two Pulsatilla chloroplast genomes ranged from 112 to 1214, and provided sufficient data for species delimitation. Phylogenetic trees based on different data sets were consistent with one another, with the IR, SSC regions and the barcode combination rbcL + matK + trnH-psbA produced slightly different results. Phylogenetic relationships within Pulsatilla were certainly resolved using the complete cp genome sequences. Overall, this study provides plentiful chloroplast genomic resources, which will be helpful to identify members of this taxonomically challenging group in further investigation.

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