Learning letter identification in peripheral vision.

Performance for a variety of visual tasks improves with practice. The purpose of this study was to determine the nature of the processes underlying perceptual learning of identifying letters in peripheral vision. To do so, we tracked changes in contrast thresholds for identifying single letters presented at 10 degrees in the inferior visual field, over a period of six consecutive days.

Gastroduodenal artery steal syndrome during liver transplantation: intraoperative diagnosis with Doppler ultrasound and management.

Arterial steal syndrome (ASS) after liver transplantation has been reported. ASS causes arterial hypo-perfusion of the graft liver and devastating consequences. However, the diagnosis tends to be delayed.

Intrahepatic biliary strictures without hepatic artery thrombosis after liver transplantation: an analysis of 1,113 liver transplantations at a single center.

Background: Intrahepatic biliary strictures (IHBS) without hepatic artery thrombosis (HAT) is a serious complication and known to increase the risk of graft failure after liver transplantation. This manuscript describes the incidence, risk factors, clinical pictures, management, and outcomes.

Methods: Between 1994 and 2002, 1,113 liver transplantations were performed in 974 adult patients.

The perception of spatial order at a glance.

Spatial order is the organizing principle of the visual areas in the brain. But to what extent does this spatial mapping help us see where things are? Observers trained to perfectly recall the spatial order of seven items presented simultaneously for 5 s were asked to report their order when flashed for only 150 ms. We found that the capacity for perceiving the order of these brief stimuli was limited by their spacing.

The role of donor bone marrow infusions in withdrawal of immunosuppression in adult liver allotransplantation.

We investigated the role of donor bone marrow cell (DBMC) infusions in immunosuppression withdrawal in adult liver transplantation. Patients enrolled were at least 3 years post-transplantation, with stable graft function. Forty-five (study group: G1) received DBMC, and 59 (control group: G2) did not.

Intestinal transplantation in children: a summary of clinical outcomes and prognostic factors in 108 patients from a single center.

We performed 124 intestinal transplants on 108 children (median age, 1.5 years) since 1994. Initial graft types included isolated intestine (I) (n=26), liver and intestine (LI) (n=26), multivisceral (MV) (n=50), and multivisceral without liver (MMV) (n=6).

"Crowding" in normal and amblyopic vision assessed with Gaussian and Gabor C's.

The purpose of this study was to investigate the extent and specificity of crowding in the normal fovea and periphery, and the central field of amblyopes, using "C"-like patterns. In the first experiment we measured the extent of crowding for C-patterns comprised of Gaussian patches, over a range of target sizes using a four-alternative forced-choice (up, down, left, right) method. We found that the extent of foveal crowding is proportional to target size.

Interventional treatment of patent ductus arteriosus in 2004.

In 2004, the interventional treatment of patent ductus arteriosus (PDA) is definitive and curative. In current practice, coils are used for smaller PDA, and devices are employed for larger PDA. Developing technologies offer small improvements in control and results, but do not appear to promise major changes in practice.

Using visual noise to characterize amblyopic letter identification.

Amblyopia is a much-studied but poorly understood developmental visual disorder that reduces acuity, profoundly reducing contrast sensitivity for small targets. Here we use visual noise to probe the letter identification process and characterize its impairment by amblyopia. We apply five levels of analysis - threshold, threshold in noise, equivalent noise, optical MTF, and noise modeling - to obtain a two-factor model of the amblyopic deficit: substantially reduced efficiency for small letters and negligibly increased cortical noise.

Combining cues in contour orientation discrimination.

The perceived orientation of a Gabor-patch contour is determined, in part, by shifts in carrier phase between the patches [Popple, A. V. & Sagi, D.

Are we going to increase the use of antidepressants up to that of benzodiazepines?

Objective: The present study compared recent trends in benzodiazepine and antidepressant consumption in Italy and projected their global sales in the future. We investigated whether the increasing use of antidepressants is associated with a progressive reduction in benzodiazepine use.

Methods: Data concerning actual quantities of benzodiazepines and antidepressants dispensed in Italy from 1995 to June 2003 were obtained from IMS Health.

Perception of mirror symmetry in amblyopic vision.

Mirror symmetry is ubiquitous in natural visual scenes, and detection of mirror symmetry seems to be a global, automatic, effortless and important aspect of visual perception. The perception of mirror symmetry has not been studied in humans with amblyopia. In this paper we measured and quantified the detection of mirror symmetry in adults with naturally occurring amblyopia.

Characterizing the mechanisms of improvement for position discrimination in adult amblyopia.

Adult amblyopes can improve positional acuity through practice; however, the neural mechanisms underlying this improvement are still not clear. In this study, seven adult amblyopes repeatedly practiced a position discrimination task in the presence of positional noise. We found that six of the seven showed systematic and significant improvements in position acuity that were both eye and orientation specific.

Sirolimus-associated hepatotoxicity in liver transplantation.

Background: Sirolimus is an immunosuppressant that exerts anti-rejection activity by inhibiting T-cell activity and is used to treat chronic rejection and calcineurin-related nephrotoxicity. Unlike tacrolimus and cyclosporine, it has no effect on calcineurin activity in liver transplant recipients.

Objective: To report correlates of survival outcomes in a series of patients with putative sirolimus-related hepatotoxicity after liver transplant.

Expanded use of transplantation techniques: abdominal wall transplantation and intestinal autotransplantation.

Surgical principles and techniques derived from organ transplantation surgery can provide novel applications in general surgery. We present an update on our 5-year experience with intestinal autotransplantation and abdominal wall transplantation. Nine patients underwent intestinal or multivisceral transplantation with the addition of 10 abdominal wall grafts to cover the large open areas from previous surgeries.

Overview of interventional pediatric cardiology in 2004.

Pediatric interventional catheterization is an expanding specialty with a range of mature, emerging, and investigative procedures and technologies. Many dysfunctional obstructions and/or shunts caused by congenital heart defects may be treated or significantly palliated in the catheterization laboratory. These include valvar pulmonary or aortic stenosis, the patent ductus arteriosus, coarctation of the aorta, branch pulmonary stenosis, atrial septal defects and even ventricular septal defects.

Transthoracic echocardiographic guidance of transcatheter atrial septal defect closure.

This study examines the safety and efficacy of transthoracic echocardiographic (TTE) guidance of atrial septal defect (ASD) device closure. We evaluated 74 patients for TTE-guided ASD closure. Fifty-six patients had successful device implantation using TTE guidance.

An analysis of the association between serum citrulline and acute rejection among 26 recipients of intestinal transplant.

Small preliminary studies suggest that serum citrulline levels may act as a marker for acute cellular rejection in small intestinal transplant recipients. The results comparing serum citrulline concentrations with biopsy-based grades of rejection are summarized here for an expanded group of 26 isolated intestinal and multivisceral transplant recipients. Other factors considered included patient and donor age and sex, ischemia time, serum creatinine, and type of transplant.

Endoscopic approach for the treatment of relapses in cystic craniopharyngiomas.

Introduction: Craniopharyngiomas are tumours of the central nervous system of dysontogenetic origin. They are most commonly localized in the sellar region and appear to originate from an embryogenetic defect of the Rathke cleft. It is universally accepted that radical surgery should be performed as first surgery because surgery after relapses usually causes more difficulty due to tighter adhesion to surrounding structures.

Preliminary experience with alemtuzumab (Campath-1H) and low-dose tacrolimus immunosuppression in adult liver transplantation.

Background: The administration of alemtuzumab (Campath-1H [C1H]; Berlex Laboratories, Montville, NJ) at transplantation prevents a vigorous immune response and is believed to allow a gradual engagement of the host immune system. We report our preliminary experience with C1H and tacrolimus (Tac) immunosuppression in adult liver transplantation.

Methods: We administered C1H and low-dose Tac to 40 adult recipients of cadaveric liver allografts between December 2001 and April 2003.

The Pathology of full-thickness cadaver skin transplant for large abdominal defects: a proposed grading system for skin allograft acute rejection.

Closure of large abdominal defects after extensive abdominal surgery is a major technical surgical problem. Failure to close the abdomen leaves the patient at risk for grave complications. Full-thickness abdominal wall skin transplantation appears to solve this problem.

Perceptual learning in contrast discrimination and the (minimal) role of context.

Unlike most visual tasks, contrast discrimination has been reported to be unchanged by practice (Dorais & Sagi, 1997; Adini, Sagi, & Tsodyks, 2002), unless practice is undertaken in the presence of flankers (context-enabled learning, Adini et al., 2002). Here we show that under experimental conditions nearly identical to those in the no-flanker practice experiment of Adini et al.