Tissue distribution of estrogen receptors alpha (ER-alpha) and beta (ER-beta) mRNA in the midgestational human fetus

We compared the expression profiles of the mRNAs of both estrogen receptors, ER-alpha and the recently cloned ER-beta, in the midgestational human fetus by semiquantitative RT-PCR. ER-alpha was most abundant in the uterus, and smaller quantities were detected in the ovary, testis, skin and gut. High amounts of ER-beta mRNA were present in fetal ovaries, testes, adrenals and spleen. In these tissues, the levels of ER-beta mRNA were higher than ER-alpha. In the uterus, however, ER-alpha mRNA was more abundant, and ER-beta mRNA was expressed only moderately. ER-beta mRNA was present at moderate to low levels in the thymus, pituitary gland, skin, lung, kidney and brain cortex. In the course of our work, using the ER-beta primers on genomic DNA, an intron of 2468 bp in length, located between nt 222 and 223 in the A/B domain of ER-beta cDNA, was detected, cloned and sequenced. The study shows that the expression profile of the two ERs is different, and ER-beta is expressed in a variety of tissues during human fetal development, suggesting different, organ-specific roles for the two receptors.

Synaptogenesis of mossy fibers induced by spatial water maze overtraining

Synaptic plasticity has been proposed as a mechanism underlying learning and memory. Synaptic reorganization of hippocampal mossy fibers has been observed after experimentally induced epilepsy, and after brief high-frequency activation inducing long-term potentiation. Furthermore, it has been suggested that synaptic changes in the hippocampus may occur after spatial learning. In this study, by using a zinc-detecting histologic technique (Timm), we demonstrate a significant increase of mossy fiber terminals in the CA3 stratum oriens region induced by training rats during 3 days in a spatial Morris water maze. In contrast, animals trained for only 1 day and animals that were just allowed to swim or were overtrained in a stress-motivated inhibitory avoidance task did not show increments of mossy fiber terminals in the stratum oriens. Electron microscopy confirmed that synaptic density of mossy fiber terminals in the stratum oriens increases significantly in water maze overtrained animals compared with the swimming control animals. Taken together, these results suggest that overtraining in a spatial learning task induces mossy fiber synaptogenesis that could be involved in the mechanisms underlying long-term memory storage. Hippocampus 1999;9:631-636.

In vivo long-term potentiation in the insular cortex: NMDA receptor dependence

It has been demonstrated that the insular cortex (IC) plays an important role in the acquisition and storage of different aversive motivated learning tasks like conditioned taste aversion, spatial maze and inhibitory avoidance. It is of particular interest to investigate whether activity-dependent modification of synaptic efficacy, a presumptive mechanism for learning and memory, is present in this cortical region. Here, we address this issue by examining the induction of synaptic plasticity, long-term potentiation (LTP) in in vivo preparations. The results showed that high frequency stimulation of the basolateral amygdaloid nucleus (Bla) induced LTP in the IC. The LTP induced by tetanus was blocked by application of the N-methyl-D-aspartate (NMDA) receptor antagonists CPP and MK-801, indicating that NMDA receptors were responsible for its induction. These results suggest that in vivo tetanus induced LTP of the Bla-IC projection is a possible mechanism for the memory-related functions performed by the IC.

The NMDA receptor antagonist CPP impairs conditioned taste aversion and insular cortex long-term potentiation in vivo

It has been proposed that long-term potentiation (LTP) a form of activity-dependent modification of synaptic efficacy, may be a synaptic mechanism for certain types of learning. Recent studies on the insular cortex (IC) a region of the temporal cortex implicated in the acquisition and storage of conditioned taste aversion (CTA), have demonstrated that tetanic stimulation of the basolateral nucleus of the amygdala (Bla) induce an N-methyl-d-aspartate (NMDA) dependent LTP in the IC of adult rats in vivo. Here we present experimental data showing that intracortical administration of the NMDA receptor competitive antagonist CPP (-3(-2 carboxipiperazin-4-yl)-propyl-1-phosphonic acid) disrupts the acquisition of conditioned taste aversion, as well as, the IC-LTP induction in vivo. These findings are of particular interest since they provide support for the view that the neural mechanisms underlying NMDA dependent neocortical LTP, constitute a possible mechanism for the learning related functions performed by the IC.

Progestins activate vascular endothelial growth factor gene transcription in endometrial adenocarcinoma cells

OBJECTIVE

To determine whether progestins activate vascular endothelial growth factor (VEGF) gene transcription in endometrial adenocarcinoma cells.

DESIGN

In vitro study.

SETTING

University reproductive biology laboratories.

PATIENT(S)

None.

INTERVENTION(S)

Ishikawa cells were transfected with VEGF promoter-luciferase reporter constructs and expression vectors encoding human progesterone receptors (hPR) A or B. The cells were treated with different progestins and antiprogestins, and luciferase activity was compared with controls.

MAIN OUTCOME MEASURE(S)

Three functional progesterone response elements (PREs) in the VEGF promoter were identified by electrophoretic mobility-shift assay, and different constructs were created to assess each PRE.

RESULT(S)

In cells expressing hPRA or B, treatment with 10 nM R5020 or 100 nM medroxyprogesterone acetate statistically significantly increased luciferase activity (3.3- to 4.8-fold). Pretreatment with 100 nM RU486 blunted the effect of 10 nM R5020, resulting only in a slight, statistically nonsignificant increase in luciferase activity (1.3- to 1.7-fold). Although three different functional PREs could be identified, no single PRE accounted for the preponderance of the luciferase activity. Full VEGF promoter activation required all three PREs.

CONCLUSION(S)

Progestins have a direct effect on VEGF gene transcription. However, hPR-mediated transcriptional regulation of the VEGF promoter is complex and cannot be localized to confined PRE sequences. Other response element motifs are likely to play a contributory role.

Modification of the Cox-Maze III Procedure Using Bipolar Radiofrequency Ablation

The Cox-Maze III procedure remains the yardstick by which all treatments for atrial fibrillation are measured. This procedure is not widely adopted because of its perceived technical complexity, invasiveness and longer procedural time. Efforts have been made by various investigators to reproduce Dr Cox's results using alternative lesion sets and energy sources. Bipolar radiofrequency (BPRF) ablation avoids the morbidity of cut-and-sew lesions, reduces procedural time and increases the likelihood of transmurality and continuity of lesions created compared to unipolar devices. Initial results are encouraging. We present our surgical technique and early experience using BPRF modification of the Cox-Maze III procedure using the Medtronic Cardioblate BP system.

Five-Meter Walk Test as a Predictor of Prolonged Index Hospitalization After Transcatheter Aortic Valve Implantation

There are no studies evaluating comprehensive predictors of transcatheter aortic valve implantation (TAVI) outcomes encompassing frailty assessments in a South-East Asian cohort. In this longitudinal single-center cohort, all patients who underwent TAVI in a tertiary cardiac center and comprehensively assessed for frailty at baseline were included in a registry. The primary outcome was to investigate frailty indices predictive of prolonged index hospitalization after TAVI. Seventy-six patients with a mean age of 77.6 ± 8.5 years were included. Mean Society of Thoracic Society Predicted Risk of Mortality score was 5.2 ± 3.0, with 11 (14.5%) patients classified as high-risk (Society of Thoracic Society Predicted Risk of Mortality >8). Mean and median index hospitalization duration were 9.2 ± 5.6 and 7 [4.5 to 9.5] days, respectively. Univariate analysis demonstrated that lower hemoglobin (Hb) (p <0.01), longer 5-meter walk test (5MWT) (p <0.01), lower dominant hand grip strength (p <0.01), the use of transaortic access (p = 0.01), new atrial fibrillation post-TAVI (p <0.01), and lower postprocedural Hb (p <0.01) were associated with longer index hospitalization duration. Multivariate linear regression demonstrated preoperative Hb, preoperative atrial fibrillation and 5MWT were independent baseline predictors of index hospitalization duration (p <0.05). Additionally, a 5MWT cutoff of 11 seconds (0.45 m/s) had a high specificity (88.6%) in predicting prolonged index hospitalization duration. In conclusion, this is the first comprehensive frailty assessment in a South-East Asian cohort demonstrating 5MWT to be a significant predictor of prolonged index hospitalization. This simple and effective frailty assessment index may be considered to optimize patient selection for TAVI.

IS THERE STILL A ROLE FOR THE CLASSICAL COX-MAZE III?

BACKGROUND

The incidence of surgery for atrial fibrillation (AF) is rising, paralleled by an increase in the types of lesion sets and energy sources used. These alternate energy sources have simplified the surgery at the expense of increased cost of consumables. The classical Cox-Maze III is the gold standard therapy with a proven efficacy in curing AF. Our complete experience with this procedure is presented.

METHODS

All 28 patients undergoing the classical Cox-Maze III procedure at our institution underwent preoperative assessment and were followed prospectively.

RESULTS

Twenty-eight patients underwent the Cox-Maze III procedure between January 2001 and May 2003. Their mean age was 65 years (range, 44-80 years). Twenty-five patients had concomitant cardiac procedures. Mean duration of AF was 8.3 years. Permanent AF was present in 82%. Mean follow-up time was 15 +/- 8 months (range, 4-30 months). There were no perioperative or late deaths, or thromboembolic events. Sixty-one per cent had early (<3 months) atrial arrhythmia. Freedom from AF at most recent clinical follow up was 93%. Freedom from late atrial arrhythmia was 82%. Freedom from late AF or atrial flutter by pacemaker interrogation or Holter assessment was 77%. Anti-arrhythmic medication use was reduced. New York Heart Association class improved from an average of 2.8 preoperatively to 1.3 postoperatively.

CONCLUSION

The result of the present study shows the safety and efficacy of the classical Cox-Maze III procedure. With the advantage of proven long-term efficacy, demonstrable safety and avoidance of costly technology, the Cox-Maze III should not be discounted as a treatment option in patients because of its perceived complexity.

Can Lightning Strike Twice? Tackling Complications From Transcatheter Aortic Valve Implantation

TAVI complications may occur in the peri- and postprocedural periods. A 79-year-old woman with known severe degenerative calcified aortic stenosis underwent transfemoral TAVI; prior to groin closure, she became hypotensive. Prosthetic valve thrombosis was confirmed with transesophageal echocardiography and computed tomography aortogram, which showed thrombus on the immobile non-coronary cusp leaflet.

Effectiveness of an online patient education video for transcatheter aortic valve implantation

Anxiety and gaps in medical knowledge have been shown to adversely affect treatment decisions amongst patients and their next-of-kin (NOK).1-3 In a busy clinical setting, physicians may find it time-consuming and challenging to address all aspects of a complex procedure, like transcatheter aortic valve implantation (TAVI) for the treatment of aortic stenosis (AS). We aim to evaluate the effectiveness of an online patient education video in improving patient and NOKs’ knowledge and reducing their anxiety for TAVI.

Common Designs of Custom-Made Fenestrated Arch Devices and Applicability of an Off-the-Shelf Design

OBJECTIVES

To analyze device designs, similarities and overlaps of custom-made fenestrated arch endografts intended for mid/distal arch thoracic endovascular aortic repair.

MATERIALS AND METHODS

A multicenter cross-sectional study analyzing custom-made anonymized graft plans was performed. Graft plans were included from a cohort of mid/distal aortic arch repairs using custom-made fenestrated aortic endografts treated at 8 centers. Grafts targeting >2 arteries were excluded. No patient/clinical data were analyzed. A descriptive analysis was performed followed by an analysis of overlap of the designs to reach a common design in which the greatest number of grafts would overlap.

RESULTS

One hundred thirty-one graft plans were included. All grafts were custom-made grafts from the COOK Medical Fenestrated arch platform. Ninety-four (71.8%) had a scallop-and-single-fenestration design, 33 (25.2%) had a single fenestration and 4 (4.3%) a single scallop. For analysis purposes, these latter 4 grafts were excluded. Two main graft plans (Plans 1 and 2) were proposed after analysis with similar configuration (1 scallop with 30 mm width, 20 mm height, 12:00 position; 1 preloaded fenestration with 8 mm diameter, 26 mm from the top of the graft and 12:00 position; tapered, with a 193 mm length and 32 mm distal diameter) but with 2 different proximal diameters of 38 mm (Plan 1) and 44 mm (Plan 2), reaching an overall feasibility of 85.8% (n=109), being 47.2% (n=60) and 38.6% (n=49) for each design, respectively.

CONCLUSION

The degree of overlap between the studied fenestrated and/or scalloped thoracic endovascular aneurysm repair (TEVAR) graft designs was high. Future studies analyzing these designs in a real-world cohort of patients are needed to further address off-the-shelf feasibility.Clinical ImpactIn a multicenter study analyzing 127 fenestrated aortic arch endograft plans from 9 aortic centers, we found that the degree of overlap between the studied fenestrated and/or scalloped arch graft designs was high and that 2 proposed graft designs would be theoretically applicable in 85.8% of cases. Future studies analyzing these designs in a real-world cohort of patients are needed to further address off-the-shelf feasibility.

Does concurrent use of intra-aortic balloon pumps improve survival in patients with cardiogenic shock requiring venoarterial extracorporeal membrane oxygenation?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'Does concurrent use of intra-aortic balloon pump (IABP) improve survival in patients with cardiogenic shock requiring venoarterial extracorporeal membrane oxygenation (VA-ECMO)?'. Altogether 472 papers were found using the reported search, of which 3 level 2 systematic reviews represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The reported comparative outcomes were mortality, weaning off extracorporeal membrane oxygenation (ECMO), vascular complications and non-vascular complications. One systematic review demonstrated significantly lower in-hospital mortality with concurrent use of IABP and VA-ECMO, while the other 2 studies showed no difference in mortality. One paper reported on the weaning success from ECMO and demonstrated significantly higher weaning success with concurrent IABP usage. Another paper reported on the complications and showed no differences in vascular and non-vascular complications. We conclude that there was no significant improvement in survival with the concurrent use of IABP and VA-ECMO for a cardiogenic shock as compared to the use of VA-ECMO alone. However, the concurrent use of IABP with VA-ECMO improved weaning success from VA-ECMO. The incidence of vascular and non-vascular complications was similar with or without IABP usage.