Peri-procedural imaging for transcatheter mitral valve replacement.

Mitral regurgitation (MR) has a high prevalence in older patient populations of industrialized nations. Common etiologies are structural, degenerative MR and functional MR secondary to myocardial remodeling. Because of co-morbidities and associated high surgical risk, open surgical mitral repair/replacement is deferred in a significant percentage of patients. For these patients transcatheter repair/replacement are emerging as treatment options. Because of the lack of direct visualization, pre- and intra-procedural imaging is critical for these procedures. In this review, we summarize mitral valve anatomy, trans-catheter mitral valve replacement (TMVR) options, and imaging in the context of TMVR.

Determination of Radiation Absorbed Dose to Primary Liver Tumors and Normal Liver Tissue Using Post-Radioembolization (90)Y PET.

BACKGROUND: Radioembolization with Yttrium-90 ((90) Y) microspheres is becoming a more widely used transcatheter treatment for unresectable hepatocellular carcinoma (HCC). Using post-treatment (90) Y positron emission tomography/computerized tomography (PET/CT) scans, the distribution of microspheres within the liver can be determined and quantitatively assessed. We studied the radiation dose of (90) Y delivered to liver and treated tumors. METHODS: This retrospective study of 56 patients with HCC, including analysis of 98 liver tumors, measured and correlated the dose of radiation delivered to liver tumors and normal liver tissue using glass microspheres (TheraSpheres(®)) to the frequency of complications with modified response evaluation criteria in solid tumors (mRECIST). (90) Y PET/CT and triphasic liver CT scans were used to contour treated tumor and normal liver regions and determine their respective activity concentrations. An absorbed dose factor was used to convert the measured activity concentration (Bq/mL) to an absorbed dose (Gy). RESULTS: The 98 studied tumors received a mean dose of 169 Gy (mode 90-120 Gy; range 0-570 Gy). Tumor response by mRECIST criteria was performed for 48 tumors that had follow-up scans. There were 21 responders (mean dose 215 Gy) and 27 non-responders (mean dose 167 Gy). The association between mean tumor absorbed dose and response suggests a trend but did not reach statistical significance (p = 0.099). Normal liver tissue received a mean dose of 67 Gy (mode 60-70 Gy; range 10-120 Gy). There was a statistically significant association between absorbed dose to normal liver and the presence of two or more severe complications (p = 0.036). CONCLUSION: Our cohort of patients showed a possible dose-response trend for the tumors. Collateral dose to normal liver is non-trivial and can have clinical implications. These methods help us understand whether patient adverse events, treatment success, or treatment failure can be attributed to the dose that the tumor or normal liver received.

Each member of the poly-r(C)-binding protein 1 (PCBP) family exhibits iron chaperone activity toward ferritin.

The mechanisms through which iron-dependent enzymes receive their metal cofactors are largely unknown. Poly r(C)-binding protein 1 (PCBP1) is an iron chaperone for ferritin; both PCBP1 and its paralog PCBP2 are required for iron delivery to the prolyl hydroxylase that regulates HIF1. Here we show that PCBP2 is also an iron chaperone for ferritin. Co-expression of PCBP2 and human ferritins in yeast activated the iron deficiency response and increased iron deposition into ferritin. Depletion of PCBP2 in Huh7 cells diminished iron incorporation into ferritin. Both PCBP1 and PCBP2 were co-immunoprecipitated with ferritin in HEK293 cells, and expression of both PCBPs was required for ferritin complex formation in cells. PCBP1 and -2 exhibited high affinity binding to ferritin in vitro. Mammalian genomes encode 4 PCBPs, including the minimally expressed PCBPs 3 and 4. Expression of PCBP3 and -4 in yeast activated the iron deficiency response, but only PCBP3 exhibited strong interactions with ferritin. Expression of PCBP1 and ferritin in an iron-sensitive, ccc1 yeast strain intensified the toxic effects of iron, whereas expression of PCBP4 protected the cells from iron toxicity. Thus, PCBP1 and -2 form a complex for iron delivery to ferritin, and all PCBPs may share iron chaperone activity.

Prevalence of negative symptoms and associated factors in older adults with schizophrenia spectrum disorder.

OBJECTIVE: To examine the prevalence of negative symptoms and associated factors in older adults with schizophrenia spectrum disorder living in the community. METHODS: The sample consisted of a multiracial sample of 198 persons aged 55 and more with a schizophrenia spectrum disorder that developed the disorder before the age of 45; 39% and 61% lived independently and in supported community residences, respectively. George's Social Antecedent Model of Psychopathology was used to examine 16 predictor variables of negative symptoms, based on scores of 4 or more on any of the PANSS negative symptom items. RESULTS: Forty percent of the sample met the criteria for the presence of negative symptoms, and this decreased to 19% when potential secondary symptoms were excluded. In bivariate analysis, 10 variables were found to be significantly associated with the presence of negative symptoms, but when the model was tested in logistic regression analysis, only 3 variables retained significance: greater positive symptom scores (odds ratio [OR] = 1.26), lower cognitive scores (OR = 0.96), and fewer confidantes (OR = 0.80). CONCLUSION: Negative symptoms do not dominate the clinical picture in later life, and levels of negative symptoms appear to be no higher than in younger schizophrenia populations. The relative paucity of significant variables and their modest effect sizes suggest that treatment for negative symptoms in later life will depend largely on strategies directed specifically at the negative symptoms.