Antigen-specific T-regulatory cells can extend skin graft survival time in mice

This study investigated the effects of donor antigen-specific CD4(+)CD25(+) T-regulatory cells (Tregs) on skin allografts in mice. An allogeneic skin transplant model was established using donor C57BL/6 or DBA and recipient BALB/c mice. Recipients were divided into 4 groups: control group without intervention (CON; C57BL/6 to BALB/c), rapamycin gavage group (RAP; C57BL/6 to BALB/c), CD4(+)CD25(+) Tregs-treated group (TRE; C57BL/6 to BALB/c), in which recipients received transfusions of CD4(+)CD25(+) Tregs stimulated with C57BL/6-derived immature dendritic cells, and the third-party donor group (DBA; DBA to BALB/c) in which recipients received transfusions of BALB/c CD4(+)CD25(+) Tregs stimulated with C57BL/6-derived immature dendritic cells. Mean (SD) survival time of the skin allografts in the TRE group was 17.0 (3.4) days, significantly longer than in the other groups: CON, 6.9 (1.9) days; RAP, 10.3 (3.0) days; and DBA, 10.8 (3.6) days. The TRE group demonstrated a significantly greater expression of transforming growth factor-β and interleukin (IL)-10. Donor antigen-specific CD4(+)CD25(+) Tregs effectively extend skin allograft survival in mice.

Abstract P5-07-01: BreastCancerTrials.org: Early Evaluation of a Nationwide Clinical Trial Matching Service

Background: In 1999, UCSF researchers and patient advocates began a collaboration to design BreastCancerTrials.org (BCT.org), a web-based clinical trial matching service. In May 2005, the UCSF Center of Excellence for Breast Cancer Care (COE) and NCI launched BCT.org as a 2-year pilot with the participation of 13 Bay Area research sites. The pilot showed that breast cancer patients were willing to use an online clinical trial matching service, that they were able to enter their detailed health history onto web-based forms, and that the system's underlying caMATCH technology led to valid matches. In a companion study to evaluate the accuracy of patient-entered data, UCSF researchers found a 93% match rate between the data UCSF patients entered in BCT.org and their corresponding clinic charts. As a result, the COE partnered with a non-profit corporation (Quantum Leap Healthcare Collaborative or QLHC) to launch a nationwide version of BCT.org in October 2008. Development: The COE and QLHC team upgraded BCT.org to include personalized questionnaires for different breast conditions; the ability to use BCT.org anonymously; and the development of more clearly presented trial information. To improve the quality of matching, the team developed TrialCODE, a caMATCH-compatible tool for coding and validating a wide range of eligibility criteria. In July 2009, BCT.org added a Trial Alert Service to inform users when newly listed trials match their history, and SecureCONNECT, a messaging platform that enables users to share their online health history with research sites. COE researchers defined metrics and configured Google Analytics to monitor user traffic and support quality improvement.

Results: As of June 2010, the BCT.org trial registry had 331 coded trials, including 213 for treatment, 63 for psychosocial/support, and 55 distributed among diagnosis/screening, prevention, and other categories. The treatment trials were evenly divided between early and advanced disease and included additional trials for individuals with DCIS. In the 18 months between Jan. 2009 and June 2010, BCT.org received 25,206 visits with traffic increasing by 36% in the first 6 months of 2010 compared to the same period in 2009. Since its launch in July 2009, the Trial Alert Service (TAS) enrolled over 1,400 subscribers. As a result, the number of returning users increased from 1,335 to 4,007 in the 6-month period leading up to its launch, compared to the 6-month period after launch. Fifty research sites have registered to use SecureCONNECT and, with patient consent, can securely view BCT. org patient health histories. During the 18 month evaluation period, 3,563 BCT.org users started a health history with 2,206 (62%) completing it and matching to trials; among the users who matched to trials, 920 users (42%) clicked through to view a list of participating research sites. Conclusion: Thousands of patients have adopted BCT.org and use it to monitor trial opportunities. The registry of breast cancer trials is diverse and growing. The COE and QLHC are working to increase participation in SecureCONNECT and evaluate its impact on the efficiency of trial screening and enrollment.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-07-01.

Numerical analysis of deep sub-wavelength integrated plasmonic devices based on Semiconductor-Insulator-Metal strip waveguides

We report the first study of nanoscale integrated photonic devices constructed with semiconductor-insulator-metal strip (SIMS) waveguides for use at telecom wavelengths. These waveguides support hybrid plasmonic modes transmitting through a 5-nm thick insulating region with a normalized intensity of 200-300 μm(-2). Their fundamental mode, unique transmission and dispersion properties are consistent with photonic devices for guiding and routing of signals in communication applications. It has been demonstrated using Finite Element Methods (FEM) that the high performance SIMS waveguide can be used to fabricate deep sub-wavelength integrated plasmonic devices such as directional couplers with the ultra short coupling lengths, sharply bent waveguides, and ring resonators having a functional size of ≈1 µm and with low insertion losses and nearly zero radiation losses.

Use of paediatric donor tissue in Descemet stripping endothelial keratoplasty

AIMS

To evaluate the feasibility, efficacy and postoperative complications of Descemet stripping endothelial keratoplasty (DSEK) with paediatric donor tissue.

METHODS

Retrospective non-comparative interventional case series. Seven consecutive cases (seven eyes) of pseudophakic bullous keratopathy were treated with DSEK using paediatric donor tissue and followed up for 12 to 18 months. Data collected included best spectacle-corrected visual acuity, spherical equivalent refractive error, corneal astigmatism, corneal curvature and endothelial cell density.

RESULTS

DSEK was successfully performed in six out of seven eyes with paediatric donor graft; one paediatric donor graft perforated during dissection. All paediatric tissue was unfolded using the "hitch suture" technique and supported with plenty of air. No graft dislocation occurred. At 12 months postoperatively, the cornea was clear in all eyes; the best spectacle-corrected visual acuity ranged from 20/67 to 20/32; the average spherical equivalent refractive error was 1.9 (0.5) dioptres; the average corneal astigmatism was 2.2 (0.6) dioptres; the average corneal curvature was 45.2 (1.6) dioptres; and the average endothelial cell density was 2247.7 (74.3) cells/mm(2) (41.4 (3.7)% of endothelial cell loss).

CONCLUSION

With high postoperative endothelial cell counts, low graft dislocation rate and absence of high myopic shifts, paediatric donor tissue can be successfully used in DSEK.

Extracardiac lesions and chromosomal abnormalities associated with major fetal heart defects: comparison of intrauterine, postnatal and postmortem diagnoses

OBJECTIVES

The clinical outcome of prenatally diagnosed congenital heart defects (CHD) continues to be affected significantly by associated extracardiac and chromosomal abnormalities. We sought to: determine the frequency and type of major extracardiac abnormalities (with impact on quality of life) and chromosomal abnormalities associated with fetal CHD; and compare the extracardiac abnormalities detected prenatally to the postnatal and autopsy findings in affected fetuses, to find the incidence of extracardiac abnormalities missed on prenatal ultrasound.

METHODS

We reviewed the computerized database of the Division of Cardiology of the Hospital for Sick Children in Toronto to identify all cases of major CHD detected prenatally from 1990 to 2002. Medical records, fetal echocardiograms and ultrasound, cytogenetic and autopsy reports were reviewed. The types of CHD detected were grouped into categories and the frequencies of major extracardiac and chromosomal abnormalities in these categories were noted. Prenatal ultrasound findings were compared with those at autopsy or postnatal examination.

RESULTS

Of 491 fetuses with major structural CHD, complete data were obtained for 382. Of these, there were 141 (36.9%) with major extracardiac abnormalities at autopsy or postnatal exam, of which 46 had chromosomal abnormalities and 95 did not. In the absence of chromosomal abnormalities, the organ systems most affected were urogenital (12.2%) and gastrointestinal (11.6%). CHDs with the highest incidence of extracardiac abnormalities (>25%) included: heterotaxy, single left ventricle and tricuspid atresia, hypoplastic left heart syndrome and tetralogy of Fallot. Ninety-four of 334 (28.1%) fetuses tested had chromosomal abnormalities. The most common chromosomal abnormalities were trisomies 21 (43.6%), 18 (19.1%) and 13 (9.6%), monosomy X (7.4%) and 22q11.2 deletion (7.4%). Of 289 extracardiac abnormalities from the complete series, 134 (46.4%) were not identified prenatally. Of the missed extracardiac abnormalities, 65 were considered not detectable at prenatal ultrasound, so 23.9% (69/289) of detectable extracardiac abnormalities were missed prenatally.

CONCLUSIONS

Major extracardiac and chromosomal abnormalities are common in fetuses with major fetal CHD. Many important associated extracardiac abnormalities may be missed prenatally, which should be taken into consideration in the prenatal counseling for fetal CHD.

Direct observation of the transition state of ultrafast electron transfer reaction of a radiosensitizing drug bromodeoxyuridine

Replacement of thymidine in DNA by bromodeoxyuridine (BrdU) has long been known to enhance DNA damage and cell death induced by ionizing/UV radiation, but the mechanism of action of BrdU at the molecular level is poor understood. Using time-resolved femtosecond laser spectroscopy, we obtain the real-time observation of the transition state of the ultrafast electron transfer (ET) reaction of BrdU with the precursor to the hydrated electron, which is a general product in ionizing/UV radiation. The results show that the ET reaction is completed within 0.2 picosecond (ps) after the electronic excitation, leading to the formation of a transition state BrdU*- with a lifetime of approximately 1.5 ps that then dissociates into Br- and a high reactive radical dU*. The present results can greatly enhance our understanding not only of the mechanism of BrdU as a radio-/photosensitizer but of the role of prehydrated electrons in electron-initiated processes in biological and environmental systems.