Percutaneous mitral repair with the MitraClip system: safety and midterm durability in the initial EVEREST (Endovascular Valve Edge-to-Edge REpair Study) cohort.

Objectives: We undertook a prospective multicenter single-arm study to evaluate the feasibility, safety, and efficacy of the MitraClip system (Evalve Inc., Menlo Park, California).

Background: Mitral valve repair for mitral regurgitation (MR) has been performed by the use of a surgically created double orifice.

Diffusion-weighted MRI of peritoneal tumors: comparison with conventional MRI and surgical and histopathologic findings--a feasibility study.

Objective: The purpose of our study was to evaluate the utility of single-shot spin-echo echo-planar diffusion-weighted imaging (DWI) using a b value of 400-500 s/mm(2) for depicting peritoneal tumors.

Materials And Methods: Thirty-four consecutive oncology patients underwent preoperative abdominal and pelvic MRI for tumor staging. MRI included breath-hold DWI with a b value of 400-500 s/mm(2), T1-weighted spoiled gradient-echo, T2-weighted fast spin-echo, and 0- and 5-minute delayed gadolinium-enhanced imaging.

Rapid onset renal deterioration in an adult with silent ureteropelvic junction obstruction.

We report a case of a rapid renal deterioration due to ureteropelvic junction obstruction (UPJO) in an asymptomatic woman with prior normal diuretic renography. This case illustrates "silent" renal obstruction and the inability of diuretic renography in detecting significant renal obstruction. This case may favor close surveillance of any adult patient with potential UPJO, especially those with underlying renal disease or solitary kidney.

Diffusion-weighted MR imaging for whole body metastatic disease and lymphadenopathy.

Diffusion-weighted (DW) imaging provides a new contrast mechanism for evaluation of tumors of the chest, abdominal, and pelvis. By imaging microscopic motion of water molecules, DW imaging yields new qualitative and quantitative information about tumors that can be used to improve tumor detection, characterize some tumors, and monitor and predict response to treatment. DW imaging techniques provide a host of new tools for the body imager including: magnitude DW images; ADC maps with quantitative analysis; and volumetric display of data including whole body diffusion with background suppression.

Observation of ultralong-range Rydberg molecules.

Rydberg atoms have an electron in a state with a very high principal quantum number, and as a result can exhibit unusually long-range interactions. One example is the bonding of two such atoms by multipole forces to form Rydberg-Rydberg molecules with very large internuclear distances. Notably, bonding interactions can also arise from the low-energy scattering of a Rydberg electron with negative scattering length from a ground-state atom.

Neuropathological correlates of temporal pole white matter hyperintensities in CADASIL.

Background And Purpose: White matter (WM) hyperintensities on MRI or leukoaraiosis is characteristic of stroke syndromes. Increased MRI signals in the anterior temporal pole are suggested to be diagnostic for cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), with 90% sensitivity and 100% specificity. The structural correlates of these specific WM hyperintensities seen on T2-weighted and FLAIR sequences in the temporal pole of CADASIL are unclear.

MR determination of glomerular filtration rate in subjects with solitary kidneys in comparison to clinical standards of renal function: feasibility and preliminary report.

This study was conducted to demonstrate the feasibility of quantifying single kidney glomerular filtration rate (skGFR) by magnetic resonance (MR) by comparison to the clinical estimates of GFR in volunteer subjects with a single kidney. Seven IRB-approved subjects with a solitary kidney, stable serum creatinine (SCr) and a 24 h creatinine clearance (CrCl) volunteered to undergo an MR examination that determined renal extraction fraction (EF) with a breathhold inversion recovery echo planar pulse sequence and renal blood flow with a velocity encoded phase imaging sequence. The product of EF and blood flow determines GFR.

Inducible expression of coding and inhibitory RNAs from retargetable genomic loci.

Conditional gene expression systems have developed into essential tools for the study of gene functions. However, their utility is often limited by the difficulty of identifying clonal cell lines, in which transgene control can be realized to its full potential. Here, we describe HeLa cell lines, in which we have identified-by functional analysis-genomic loci, from which the expression of transgenes can be tightly controlled via tetracycline-regulated expression.

Quantum critical behavior in strongly interacting Rydberg gases.

We study the appearance of correlated many-body phenomena in an ensemble of atoms driven resonantly into a strongly interacting Rydberg state. The ground state of the Hamiltonian describing the driven system exhibits a second order quantum phase transition. We derive the critical theory for the quantum phase transition and show that it describes the properties of the driven Rydberg system in the saturated regime.

Direct flow medical percutaneous aortic valve: proof of concept.

Aims: This paper reports the technical feasibility of using the Direct Flow Medical percutaneous aortic valve (PAV) to treat patients with severe aortic stenosis (AS).

Methods And Results: Eight patients with critical AS underwent temporary implantation of the PAV. Two patients received open surgical implantation of the device while six patients underwent percutaneous implantation.

The use of retroviral vectors for tet-regulated gene expression in cell populations.

Today the treatment of inherited diseases holds a major field in gene therapy, and gamma -retroviral vectors are often the preferred tool for stable introduction of the therapeutic gene(s) into the host cell genome. In many cases, the newly introduced gene has to be constitutively expressed, since enzyme function often is required at all times. However, in some cases gene function might be demanded only transiently, making a strict control of gene expression necessary.

Use of a surgical helmet system to minimize splash injury during percutaneous renal surgery in high-risk patients.

The transmission risk to surgeons performing percutaneous renal surgery on patients who are infected with human immunodeficiency virus/acquired immunodeficiency syndrome, hepatitis B, or hepatitis C is unknown. A recent study found 55% of surgeons' masks contain evidence of blood splash contamination after percutaneous nephrolithotomy. While the risk of infectious disease transmission to the surgeon after mucocutaneous exposure is unknown, the incapacitating disease these pathogens cause can have a devastating and permanent effect on a surgeon's career.

High-frequency vibration for the recanalization of guidewire refractory chronic total coronary occlusions.

Background: Recanalization of coronary chronic total occlusions (CTOs) remains a clinical challenge, particularly when standard guidewire attempts fail.

Objectives: We sought to determine the safety and efficacy of a novel method that used high-frequency (20 kHz) vibration to fragment occlusive fibrous tissue and facilitate guidewire crossing into the distal vessel.

Methods: A total of 125 patients with CTO, who failed at attempts of conventional guidewire recanalization after more than 5 min of fluoroscopy time, were enrolled in the study.

Vertebral fracture in a pilot during centrifuge training: finding of osteopenia.

We report on a case of an F-16 pilot who suffered a compression fracture of the L5 vertebral body during centrifuge training. The pilot sustained the injury during a rapid onset to 6 G run. He was subsequently diagnosed to have osteopenia with a bone mineral density T-score of -1.

Tandem conjugate addition-elimination reaction promoted by chiral pyrrolidinyl sulfonamide (CPS).

Chiral pyrrolidinyl sulfonamides have been found to promote the conjugate addition-elimination reaction between activated allylic bromides and 1,3-dicarbonyl compounds with high enantioselectivities and the highly functionalised products can be used to generate a variety of interesting enantiomerically pure compounds via simple transformations.

Retrograde transarterial implantation of a nonmetallic aortic valve prosthesis in high-surgical-risk patients with severe aortic stenosis: a first-in-man feasibility and safety study.

Background: To assess the feasibility and safety of retrograde transarterial implantation of a novel nonmetallic aortic valve prosthesis (Direct Flow Medical Inc, Santa Rosa, Calif), a prospective single-center study was performed in patients with severe aortic stenosis at high risk for open-heart surgery.

Methods And Results: Fifteen patients (intention-to-treat cohort) with an aortic valve area < or = 0.8 cm(2), a > or = 35-mm Hg mean transvalvular pressure gradient, and a logistic EuroSCORE > or = 20% were enrolled.

Three-dimensional fast spoiled gradient-echo dual echo (3D-FSPGR-DE) with water reconstruction: preliminary experience with a novel pulse sequence for gadolinium-enhanced abdominal MR imaging.

Purpose: To compare three-dimensional fast spoiled gradient-echo dual-echo (3D-FSPGR-DE) with water reconstruction to conventional 3D-FSPGR for gadolinium-enhanced abdominal imaging.

Materials And Methods: Sixty-five patients underwent abdominal MRI on a 1.5T GE-HDx MR scanner using gadolinium-enhanced 3D-FSPGR and 3D-FSPGR-DE imaging.

Identifying teachers at risk in Hong Kong: Psychosomatic symptoms and sources of stress.

Objective: The present study attempts to examine the relationships between certain common psychosomatic symptoms and sources of stress in Hong Kong teachers.

Methods: A total of 261 teachers (134 males and 127 females) from 13 high schools in different regions of Hong Kong responded to the Teacher Stress Inventory (TSI) with a return rate of 52.2%.

Identification and molecular characterization of a novel PDE4D11 cAMP-specific phosphodiesterase isoform.

Here we report the cloning and characterization of a novel PDE4D isoform (PDE4D11) identified in mouse brain cDNA. This novel isoform has a unique isoform-specific 5'-UTR and N-terminal sequence, whereas, downstream regulatory N-terminal and catalytic C-terminal regions are homologous to other long PDE4D isoforms (Ex2-15). In silico analysis of PDE4D11 cDNA transcript identified the predicted translational start site and the use of a different transcriptional start site compared to other PDE4D isoforms.

Evaluation of the impact and need for use of a safety guidewire during ureteroscopy.

Background And Purpose: The routine use of a "safety" guidewire adjacent to the ureteroscope during upper tract endoscopy is advocated in surgical texts and by many endourologists. Our experience has led us to theorize that a safety guidewire complicates ureteroscopy by providing resistance to introduction of the endoscope and by creating an obstruction to ureteroscopic instrumentation. To examine our theory, we developed a porcine animal model to evaluate the impact of the presence of a safety guidewire and reviewed our clinical experience, which routinely does not use a safety guidewire during ureteroscopy.

Current laparoscopy training in urology: a comparison of fellowships governed by the Society of Urologic Oncology and the Endourological Society.

Background And Purpose: Laparoscopic surgery is now an integral technique in the practice of urology, particularly in the management of certain urologic malignancies. Advanced laparoscopy training in urology is primarily reserved for those pursuing fellowship training and is offered both by traditional endourology fellowships and increasingly in urologic oncology fellowships. The purpose of our study was to evaluate and compare current laparoscopy training at the fellowship level.

Functional effects of the hypertrophic cardiomyopathy R403Q mutation are different in an alpha- or beta-myosin heavy chain backbone.

The R403Q mutation in the beta-myosin heavy chain (MHC) was the first mutation to be linked to familial hypertrophic cardiomyopathy (FHC), a primary disease of heart muscle. The initial studies with R403Q myosin, isolated from biopsies of patients, showed a large decrease in myosin motor function, leading to the hypothesis that hypertrophy was a compensatory response. The introduction of the mouse model for FHC (the mouse expresses predominantly alpha-MHC as opposed to the beta-isoform in larger mammals) created a new paradigm for FHC based on finding enhanced motor function for R403Q alpha-MHC.

Mucinous appendiceal neoplasms: preoperative MR staging and classification compared with surgical and histopathologic findings.

Objective: The objective of our study was to determine the accuracy of MRI in the preoperative staging and classification of mucinous appendiceal neoplasms and to describe the MRI features that are useful for selecting patients for surgical resection.

Materials And Methods: Twenty-two patients underwent preoperative MRI including T1-weighted, T2-weighted, immediate gadolinium-enhanced, and delayed gadolinium-enhanced imaging. Two observers reviewed the images for peritoneal tumor at 13 sites, tumor size and distribution, and degree of tumor enhancement.