Morphological characterization of the human corneal epithelium by in vivo confocal laser scanning microscopy

Background

Regarding the growing interest and importance of understanding the cellular changes of the cornea in diseases, a quantitative cellular characterization of the epithelium is becoming increasingly important. Towards this, the latest research offers considerable improvements in imaging of the cornea by confocal laser scanning microscopy (CLSM). This study presents a pipeline to generate normative morphological data of epithelial cell layers of healthy human corneas.

Methods

3D in vivo CLSM was performed on the eyes of volunteers (n=25) with a Heidelberg Retina Tomograph II equipped with an in-house modified version of the Rostock Cornea Module implementing two dedicated piezo actuators and a concave contact cap. Image data were acquired with nearly isotropic voxel resolution. After image registration, stacks of en-face sections were used to generate full-thickness volume data sets of the epithelium. Beyond that, an image analysis algorithm quantified en-face sections of epithelial cells regarding the depth-dependent mean of cell density, area, diameter, aggregation (Clark and Evans index of aggregation), neighbor count and polygonality.

Results

Imaging and cell segmentation were successfully performed in all subjects. Thereby intermediated cells were efficiently recognized by the segmentation algorithm while efficiency for superficial and basal cells was reduced. Morphological parameters showed an increased mean cell density, decreased mean cell area and mean diameter from anterior to posterior (5,197.02 to 8,190.39 cells/mm²; 160.51 to 90.29 µm²; 15.9 to 12.3 µm respectively). Aggregation gradually increased from anterior to posterior ranging from 1.45 to 1.53. Average neighbor count increased from 5.50 to a maximum of 5.66 followed by a gradual decrease to 5.45 within the normalized depth from anterior to posterior. Polygonality gradually decreased ranging from 4.93 to 4.64 sides of cells. The neighbor count and polygonality parameters exhibited profound depth-dependent changes.

Conclusions

This in vivo study demonstrates the successful implementation of a CLSM-based imaging pipeline for cellular characterization of the human corneal epithelium. The dedicated hardware in combination with an adapted image registration method to correct the remaining motion-induced image distortions followed by a dedicated algorithm to calculate characteristic quantities of different epithelial cell layers enabled the generation of normative data. Further significant effort is necessary to improve the algorithm for superficial and basal cell segmentation.

'I'm not a real boozer': a qualitative study of primary care patients' views on drinking and its consequences

BACKGROUND

The public health message around alcohol is complex, with benefits versus harms, the confusing concept of risk and drinking guidance changing over time. This provides a difficult context for alcohol screening in primary care, with established barriers from the practitioner perspective, but less is known about the patients' perspective. This study explores patients' views on drinking.

METHODS

Eligible participants were recorded as drinking above low risk levels in primary care. Six practices in North London participated. Interviews were in-depth, semi-structured, transcribed verbatim and underwent detailed thematic analysis.

FINDINGS

Interviews were conducted with 8 women and 12 men, aged 26-83 years, mostly educated to undergraduate level and of 'White' ethnicity. UK drinking guidance was viewed as irrelevant for reasons related to life stage, lifestyle and absence of harm. Dependence, loss of functionality and control were perceived as key features of problematic drinking. Healthy lifestyles, in terms of diet, exercise and not smoking, were thought to mitigate potential problems associated with alcohol intake.

CONCLUSION

The findings suggest that public health messages and brief advice should focus on harm experienced at different life stages, among people with different lifestyles, to challenge the ubiquitous view that 'I'm not a real boozer'.

Abstract GS5-08: A validation of DCIS biological risk profile in a randomised study for radiation therapy with 20 year follow-up (SweDCIS)

Background: Women diagnosed with ductal carcinoma in situ (DCIS) and their physicians need tools that assess individualized risk and predict treatment benefit. A DCIS biologic signature was previously validated in an observational study at Kaiser Permanente NW. We evaluated the results of the signature for predictive utility in a national randomized clinical trial (SweDCIS) by assessing the 10-year benefit of adjuvant radiotherapy (RT) on ipsilateral breast event (IBE) and invasive breast cancer (IBC) risks.

Methods: The signature was validated in a prospective-retrospective study in women from the SweDCIS trial (n=1046) performed by the Swedish Breast Cancer Group. Women were treated with breast conserving surgery (BCS) between 1987-1999 and randomized to RT or no RT. A central pathology review of paraffin embedded tissue blocks (n=873) was performed at Uppsala University (UU). Freshly cut slides were provided to PreludeDx for biomarker testing. Extended follow-up of SweDCIS was published in 2014.

A panel of biomarkers (HER2, PR, Ki67, COX2, p16/INK4A, FOXA1 and SIAH2) were assayed and scored in PreludeDx's CLIA lab by board-certified pathologists. Continuous Decision Scores (DS) were calculated with the biologic signature using the biomarker and clinical factors (age, size, margin, and palpability) blinded to patient outcome. The DS results were provided to the Uppsala Regional Cancer Center for analysis. A predefined and co-developed statistical analysis plan was executed. Absolute 10-year RT benefit was assessed using Kaplan-Meier survival analysis. Hazard ratios (HR) were determined using Cox proportional hazards analysis and the interaction of the DS and RT benefit was assessed.

Results: Complete biomarker and clinical information was available in 584 women. In women with clear margins (n=506), 78 IBEs, including 31 IBCs, were recorded within 10 years of diagnosis. The multivariate analysis of DS (0-10 unit scale) and the RT interaction was significant for risk of IBC (p=0.048) and IBE (p<0.001) at 10 years. The DS defined an elevated risk group (>3) for which there was pronounced 10-year benefit of RT (p=0.01) with an absolute risk reduction of 9% for IBC (Table 1). The corresponding low risk group (≤3), which included 48% of all patients, demonstrated no significant RT benefit (p=0.70) with an absolute risk reduction of 1%. The continuous DS variable was correlated with IBE risk, HR 1.49/per 5 units 95%CI[1.02,2.18] (p=0.038), in addition to the RT benefit for IBE in low (p=0.04) and elevated (p<0.001) risk groups.

Table 1. 10-year RT benefit in women from the SweDCIS trial.DS Risk GroupsIBC eventsIn Situ or IBC eventsnAbsolute RT-benefitHR [95%CI] Absolute RT-benefit HR [95%CI]Low Risk Group (DS≤3)2431%0.83 [0.32, 2.16]9%0.48 [0.24-0.97]Elevated Risk Group (DS>3)2639%0.24 [0.08, 0.73]17%0.31 [0.17-0.59]

Discussion: Evaluation of the SweDCIS trial validated prognostic and RT predictive utility of the biologic signature. Women diagnosed with DCIS and treated with BCS±RT were stratified into clinically relevant low and elevated risk groups (≤3 vs >3). Women in the elevated risk group had twice the treatment benefit for IBC from RT compared to prior randomized trials, while the low risk group had no benefit from RT.

Citation Format: Wärnberg F, Garmo H, Folkvaljon Y, Holmberg L, Karlsson P, Sandelin K, Linke S, Lyle S, Simin K, Leesman G, Barry T, Savala J, Whitworth P, Bremer T. A validation of DCIS biological risk profile in a randomised study for radiation therapy with 20 year follow-up (SweDCIS) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr GS5-08.

Abstract S5-01: DCIS biological risk profile predicts risk of recurrence after breast conserving surgery in a Kaiser Permanente NW population

Background: Patients with DCIS and their physicians need tools that provide better information about the individual patient's biological risk profile to help make treatment decisions. Prelude and the Kaiser Permanente Northwest Center for Health Research (KPCHR) validated a biological risk signature based test to assess ipsilateral breast event (IBE) risk after breast conserving surgery (BCS) with radiation (+RT) or without radiation therapy (-RT).

Methods: The Prelude DCIS test was independently validated in a retrospective cohort from the Kaiser Permanente Northwest (KPNW) integrated healthcare system in patients diagnosed with DCIS from 1990- 2007 and treated with BCS±RT(n=608). KPCHR performed central pathology review to identify patients meeting study eligibility criteria with formalin fixed paraffin embedded (FFPE) tissue samples (n=475); KPCHR also reviewed medical records to collect patient, treatment, and outcome data. FFPE patient samples were provided to Prelude for testing. REMARK guidelines were followed.

A panel of biomarkers (HER2, PR, Ki-67, COX2, p16/INK4A, FOXA1 and SIAH2) were assayed by the Prelude CLIA lab and scored by board-certified pathologists (n=455). Prelude's DCIS test was executed independently using biomarker and clinicopathologic data while blinded to patient outcome data. The risk results were provided to KPCHR under a Data Transfer Authority. KPCHR biostatisticians executed a predefined and co-developed statistical analysis plan. IBE rates were assessed using Kaplan-Meier survival analysis. Hazard ratios (HR) were determined using Cox proportional hazards analysis, with RT as a covariate.

Results: The Prelude DCIS test score was statistically associated with total IBE as a continuous linear variable (0-10 unit scale) on a per unit basis, HR of 1.12, 95% CI [1.03,1.23], p=0.01. The DCIS test score (0-10) corresponded to recurrence risks ranging from 10% to 42% (≤2, >7) for patients treated with BCS-RT and ranging from 4% to 11% (≤2, >7) for patients treated with BCS+RT. Patients treated with BCS ±RT with an elevated test score (≤3 vs >3) had a higher recurrence risk, n=455, HR=1.87 [1.03 - 3.38], p=0.04. In patients treated with BCS-RT in this sample, patients with a higher DCIS signature had an elevated recurrence risk, n=78, HR=2.37, 95% CI [0.82, 6.85], p=0.11. The 10-year contralateral breast event rate was 4%, 95% CI [2%, 6%]. Median follow-up time was 10.4 years.

Discussion: Patients diagnosed with DCIS and treated with BCS ±RT, were stratified into clinically relevant low and elevated risk groups (≤3 vs >3) in an independent validation of the Prelude DCIS test. Patients in the elevated risk group had substantially higher likelihood of 10-year total IBE. The number of patients treated with BCS -RT was limited and while the stratification by risk group for BCS -RT was in the expected direction, it did not reach statistical significance. Two additional validation studies are scheduled to be completed in 2016.

10-YEAR IBE RISKBCS –RTBCS +RTRisk, [95% CI]PrevalenceNRisk, [95% CI]PrevalenceNBaseline Total Risk20%, [12%, 32%]100%788%, [5%, 11%]100%377Low Risk Group (≤3)10% [3%, 29%]53%415%, [2%, 10%]40%149Elevated Risk Group (>3)30%, [17%, 51%]47%3710%, [6%, 15%]60%228

Citation Format: Bremer T, Whitworth P, Leo M, Barry T, Goldstein N, Ganders C, Francisco M, Leesman G, Linke S, Patel R, Pellicane J, Weinmann S. DCIS biological risk profile predicts risk of recurrence after breast conserving surgery in a Kaiser Permanente NW population [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr S5-01.

A Web-based intervention used in general practice for people with excessive alcohol consumption

Down Your Drink is a Web-based brief intervention for hazardous drinkers. We conducted a pilot study of its usefulness in general practice. Visitors to the Website were invited to complete the Fast Alcohol Screening Test and positive responders were offered a six-week interactive Web-based programme. There were 1 319 registrations in the six-month study period. In all, 815 (62%) registrants completed week one, and 79 (6%) stayed with the programme until the end. Usage of the Website was distributed through the day, with the highest levels between 10:00 and 14:00. Two focus groups with general practitioners were conducted to explore the potential for using the site in primary-care settings. Website interventions for excessive drinkers therefore appear to be feasible and may prove a useful additional tool for intervention in general practice.

[Astigmatism after keratoplasty: influence of orthotopic transplantation]

BACKGROUND

Patients undergoing corneal transplantation often suffer from postoperative reduced vision due to high astigmatism. This retrospective study analyzed the influence of heterotopic or orthotopic transplantation on astigmatism and visual outcome.

PATIENTS AND METHODS

In this study 373 eyes of 334 patients were analyzed. Group 1 (OT) contained 186 eyes, which underwent orthotopic transplantation (side of recipient and donor corresponded), whereas group 2 (HT) included 187 heterotopic keratoplasties (donor cornea placed in the recipient's contralateral side). After 1, 3, 6, 12 and 24 months the median of keratometric astigmatism, objective astigmatism, topographic astigmatism and best corrected visual acuity (BCVA) were assessed and compared between groups.

RESULTS

The long-term results showed no statistically significant differences regarding keratometric and objective astigmatism, whereas topographic astigmatism differed significantly (p = 0.04) after 3 months. We observed a lower astigmatism of 5.7 dpt (range 3.08-7.78 dpt) in group OT than in the group HT with 7.1 dpt (range 3.9-10.7 dpt). No differences were found at the other time points. The BCVA showed a significantly better effect after 1 month (p = 0.01) in the OT group of 0.2 (0.1-0.3) than in HT group of 0.1 (0.05/0.25). In the postoperative course no additional significant dissimilarities were documented.

CONCLUSIONS

Heterotopic and orthotopic keratoplasty show no significant long-term differences in astigmatism and visual outcom.

Comparison of the effects of albumin 5%, hydroxyethyl starch 130/0.4 6%, and Ringer's lactate on blood loss and coagulation after cardiac surgery

BACKGROUND

Infusion of 5% human albumin (HA) and 6% hydroxyethyl starch 130/0.4 (HES) during cardiac surgery expand circulating volume to a greater extent than crystalloids and would be suitable for a restrictive fluid therapy regimen. However, HA and HES may affect blood coagulation and could contribute to increased transfusion requirements.

METHODS

We randomly assigned 240 patients undergoing elective cardiac surgery to receive up to 50 ml kg(-1) day(-1) of either HA, HES, or Ringer's lactate (RL) as the main infusion fluid perioperatively. Study solutions were supplied in identical bottles dressed in opaque covers. The primary outcome was chest tube drainage over 24 h. Blood transfusions, thromboelastometry variables, perioperative fluid balance, renal function, mortality, intensive care unit, and hospital stay were also assessed.

RESULTS

The median cumulative blood loss was not different between the groups (HA: 835, HES: 700, and RL: 670 ml). However, 35% of RL patients required blood products, compared with 62% (HA) and 64% (HES group; P=0.0003). Significantly, more study solution had to be administered in the RL group compared with the colloid groups. Total perioperative fluid balance was least positive in the HA group [6.2 (2.5) litre] compared with the HES [7.4 (3.0) litre] and RL [8.3 (2.8) litre] groups (P<0.0001). Both colloids affected clot formation and clot strength and caused slight increases in serum creatinine.

CONCLUSIONS

Despite equal blood loss from chest drains, both colloids interfered with blood coagulation and produced greater haemodilution, which was associated with more transfusion of blood products compared with crystalloid use only.

Subjective pain, visual recovery and visual quality after LASIK, EpiLASIK (flap off) and APRK - a consecutive, non-randomized study

INTRODUCTION

Laser in situ keratomileusis (LASIK) is superior to surface ablation techniques (SAT) such as alcohol photorefractive keratectomy (APRK) or Epi-LASIK (EpiK) in terms of visual recovery and postoperative pain. This study compares subjective symptoms and visual recovery of two different SATs with LASIK.

MATERIALS AND METHODS

One hundred and twenty seven patients were operated using one of the three techniques. Patients filled out a questionnaire describing symptoms assessing subjective visual recovery on a linear scale from 'not functioning' to 'full visual function' and pain on a linear scale from 'no pain' to 'severe daily pain'. Subjective symptoms such as halos, double vision, low night vision, reduced contrast and dry eyes were also evaluated.

RESULTS

Visual recovery was faster and discomfort symptoms less pronounced with the LASIK than with surface ablation procedures. More pain was reported after APRK than after EpiK (flap-off technique) in the early postoperative period, with a maximum of pain on postoperative days 3-4. Subjective visual recovery showed no statistically significant difference between the two surface ablation procedures. Halos, double vision, low night vision, reduced contrast and dry eyes were more extensively reported by the EpiK than the APRK group and were less pronounced in the LASIK than in the SAT group.

DISCUSSION AND CONCLUSIONS

Our study does not uniformly support the previously published favourable results of EpiK compared to APRK with regard to subjective recovery of vision and postoperative pain.

High-energy, ceramic-disk Yb:LuAG laser amplifier

We report the first short-pulse amplification results to several hundred millijoule energies in ceramic Yb:LuAG. We have demonstrated ns-pulse output from a diode-pumped Yb:LuAG amplifier at a maximum energy of 580 mJ and a peak optical-to-optical efficiency of 28% at 550 mJ. In cavity dumped operation of a nanosecond oscillator we obtained 1 mJ at up to 100 Hz repetition rate. A gain bandwidth of 5.4 nm was achieved at room temperature by measuring the small-signal single-pass gain. Furthermore, we compared our results with Yb:YAG within the same amplifier system.

Detection of Helicobacter pylori in biofilms by real-time PCR

Helicobacter pylori is a cause of peptic ulcer disease and a causative agent of gastric cancer. Currently, a possible waterborne route of transmission or a possible survival in drinking water biofilms is discussed. H. pylori, like many other bacterial strains, has the ability to enter the viable but nonculturable state (vbnc) in case of unfavorable conditions. Therefore it is necessary to develop new analysis tools for vbnc bacteria. We established a fast and reliable method to detect H. pylori in drinking water biofilms by quantitative real-time PCR which makes it redundant to use difficult cultivation methods for nonculturable bacteria. With this method it was possible to identify water biofilms as a niche for H. pylori. The real-time PCR analysis targets the ureA subunit of the Helicobacter pylori urea gene which showed high specificity and sensitivity. The quantitative real-time PCR was used to detect H. pylori in biofilms of different age, unspiked and spiked with predetermined levels of cells. The drinking water biofilms were generated in a silicone-tube model. The DNA-sequences for probe and primers showed no cross-homologies to other related bacteria and it was possible to detect less than 10 genomic units of H. pylori. This novel method is a useful tool for a fast screening of drinking water biofilms for H. pylori. The results suggest that drinking water biofilms may act as a reservoir for H. pylori which raises new concerns about the role of biofilms as vectors for pathogens like Helicobacter pylori.

Translation of a Pathology-Based Prognostic Marker Profile into a Validated Clinical Tool To Guide Adjuvant Treatment Decisions

Background: We previously developed a marker profile with a risk of recurrence algorithm for patients with operable, hormone receptor-positive breast cancer to help guide the appropriate level of adjuvant treatment. Development was done using robust cross-validation methods in two patient sets: University Hospital Basel (UHB) and Institut Paoli-Calmettes (IPC). Unlike most similar tests, which assess RNA transcript levels in homogenized mixtures of tumor and surrounding normal cells, our profile is based predominantly on functional protein markers assessed specifically in tumor cells by certified pathologists. In addition, standard clinicopathologic risk factors (tumor size, tumor grade, and nodal status) are incorporated into the algorithm to the extent that they are not replaced by the molecular markers, enabling a global assessment of risk. The goal of this study was to translate the profile into a validated laboratory test available for clinical use and to assess its performance in all available patients.Methods: ER, PR, HER2, EGFR, BCL2, and p53 (IHC) and MYC/8q24 (FISH) assays were validated in a CLIA-certified central reference laboratory. The assays were conducted on TMAs of patients from Royal Perth Hospital (RPH). An algorithm was used to assign a risk score to all stage I-IIIA patients in all three patient sets (UHB, IPC, and RPH) on a scale of 0 to 10+. A pre-determined risk score threshold of 3.8 was used to separate patients into low and high risk groups.Results: In an independent validation of the algorithm in the hormone therapy (HT) only-treated RPH patients (n=144), the low-risk group had a 10-year recurrence rate &lt;5%, and the high-risk group had a recurrence rate more than ten times higher (p&lt;0.0001). When all HT only-treated patients from the UHB, IPC, and RPH patient sets were combined (n=444), the profile separated patients into low and high risk groups with 10-year recurrence rates of 4% and 40%, respectively (HR=10, 95%CI=5 to 20, p&lt;0.0001). In multivariate analyses, the profile was independent and fully replaced the significance of all individual prognostic factors and clinical treatment guideline combinations. A continuous risk curve demonstrated that risk of recurrence increased steadily with higher risk scores (p&lt;0.0001). Within the group of patients with Adjuvant! Online scores &gt;15% (n=228), the profile reclassified as low risk 85% (n=77/92) of pN0 patients and 35% (n=33/90) of pN1 patients, and both of these low-risk subgroups had only a 6% 10-year recurrence rate.Conclusion: The marker profile was validated both analytically and clinically in a CLIA-certified reference laboratory. It replaced and exceeded the prognostic value of all available individual factors and current multivariate treatment guidelines. This justified release to clinicians for diagnostic use and indicates that it is a strong candidate for future comparative studies with other treatment decision-making tools.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4055.

Retinal cells integrate into the outer nuclear layer and differentiate into mature photoreceptors after subretinal transplantation into adult mice

Vision impairment caused by degeneration of photoreceptors, termed retinitis pigmentosa, is a debilitating condition with no cure presently available. Cell-based therapeutic approaches represent one treatment option by replacing degenerating or lost photoreceptors. In this study the potential of transplanted primary retinal cells isolated from neonatal mice to integrate into the outer nuclear layer (ONL) of adult mice and to differentiate into mature photoreceptors was evaluated. Retinal cells were isolated from retinas of transgenic mice ubiquitously expressing enhanced green fluorescence protein (EGFP) at either postnatal day (P) 0, P1 or P4 and transplanted into the subretinal space of adult wild-type mice. One week to 11 months post-transplantation experimental retinas were analyzed for integration and differentiation of donor cells. Subsequent to transplantation some postnatal retinal cells integrated into the ONL of the host and differentiated into mature photoreceptors containing inner and outer segments as confirmed by immunohistochemistry and electron microscopy. Notably, the appearance of EGFP-positive photoreceptors was not the result of fusion between donor cells and endogenous photoreceptors. Retinal cells isolated at P4 showed a significant increase in their capacity to integrate into the ONL and to differentiate into mature photoreceptors when compared with cells isolated at P0 or P1. As cell suspensions isolated at P4 are enriched in cells committed towards a rod photoreceptor cell fate it is tempting to speculate that immature photoreceptors may have the highest integration and differentiation potential and thus may present a promising cell type to develop cell replacement strategies for diseases involving rod photoreceptor loss.

Millijoule pulse energy Q-switched short-length fiber laser

We report on a Q-switched short-length fiber laser producing 100 W of average output power at 100 kHz repetition rate and pulse durations as short as 17 ns. Up to 2 mJ of energy and sub-10-ns pulse duration are extracted at lower repetition rates. This performance is obtained by employing a rod-type ytterbium-doped photonic crystal fiber with a 70 microm core as gain medium, allowing for very short pulse durations, high energy storage, and emission of a single-transverse-mode beam.

A randomized controlled trial of an interactive Web-based intervention for reducing alcohol consumption

In an uncontrolled pilot study of an interactive, Web-based treatment programme for people with alcohol problems, the mean number of units consumed decreased from 33 per week to 23. A two-arm online randomized controlled trial will be conducted to determine the effectiveness of an interactive Web-based intervention for reducing alcohol consumption. Participants will be randomized to intervention (access to an interactive Web-based intervention plus information) or control (access to an information Web-site only) groups, and followed up for six months. The primary outcome measure will be reduction in units of alcohol consumed in the previous seven days; secondary outcome measures will determine effects on alcohol dependence, alcohol-related harm and social disruption and quality of life. Recruitment, consent, randomization, intervention and follow-up will all be delivered on-line.

[West Nile virus--causative agent of a zoonosis with increasing significance?]

The epidemic West Nile Virus (WNV) infections observed in the last years, particularly those in the USA in 1999 and the following years, have led to an increasing interest in this zoonotic infection. Here, the most prominent aspects of WNV biology and epidemiology are presented. Clinical signs observed in men and horses are described, as well as the current state of diagnostics and immunoprophylaxis. Preliminary results of investigations on the prevalence of WNV in Germany show that migrating birds have been in contact with WNV; there is however no indication for the presence of this virus. While WNV is endemic in many parts of the "Old World", thus inducing "natural immunity" in (migrating) birds and vertebrates, a susceptible bird population with no existing immunity against this virus was exposed in the "New World".

In vivo confocal microscopy of pre-endothelial deposits

BACKGROUND

Deposits in various layers of the cornea might result from long-term medical therapy, photorefractive surgery, and longterm use of contact lenses or corneal dystrophies.

METHODS

A 46-year-old woman was referred to our department with the suspected diagnosis of posterior polymorphous dystrophy. Slit-lamp biomicroscopy revealed bilateral small-sized deposits in the posterior part of the cornea. In vivo confocal microscopy was performed to evaluate these deposits in detail.

RESULTS

In vivo confocal microscopy of the cornea identified hyperreflec-tive "dot-like" structures in the deep stromal layer and anterior to the endothelial cell layer. The morphology and number of keratocytes of the posterior stroma and of endothelial cells appeared normal.

CONCLUSIONS

In vivo confocal microscopy is a very useful tool to analyze and visualize pre-endothelial deposits. Because there is no family history of corneal disease, the exact origin of the pre-endothelial deposits in our case remains unclear.

DOWN YOUR DRINK: A WEB-BASED INTERVENTION FOR PEOPLE WITH EXCESSIVE ALCOHOL CONSUMPTION

AIMS

To conduct a pilot study of the usefulness of Down Your Drink (DYD), a web-based intervention to encourage excessive drinkers to adopt a healthy pattern of drinking and reduce alcohol-associated harm. The DYD website was structured as a 6-week programme, derived from a manual which included elements of motivational approaches and cognitive behavioural therapy.

METHODS

Visitors whose responses to the Fast Alcohol Screening Test were positive, and those indicating excessive alcohol consumption, were encouraged to register. Users completed alcohol dependence and mental health questionnaires before the programme, and a drinking diary at each of the weekly sessions. Follow-up questionnaires were sent electronically to those who completed the programme, or who missed three or more sessions.

RESULTS

During the 6-month study there were 7581 visits to the site and 1319 registrations. Of the registrants, 61.8% completed week 1, and 6.0% stayed with the programme until the end. The 6% who stayed for 6 weeks provided encouraging feedback about the value of the site. Little information was obtained from those who dropped out, but some reported that the programme was too time-consuming.

CONCLUSIONS

Web site interventions for excessive drinkers are feasible and merit evaluation of their effectiveness.

Catalytic determination of sulfide in blood

A catalytic method, based on the iodine-azide reaction, of the determination of sulfide in whole human blood is described. The method involves generation of hydrogen sulfide in an evolution-absorption apparatus by addition of sulfuric acid and subsequent trapping of the generated hydrogen sulfide in sodium hydroxide solution. The catalytic method allows the determination of sulfide without any interference from other sulfur compounds present in blood. A linear calibration graph was obtained over the range 1 x 10(-6)-5 x 10(-4) mol dm-3 sulfide and the proposed method is compared with an ion-selective electrode method.

Protein-kinase-A-dependent activator in transcription factor CREB reveals new role for CREM repressors

Hormonally induced increases in cyclic AMP levels induce phosphorylation of the transcription factor CREB at a serine residue at position 133 by protein kinase A (ref. 1), enhancing its ability to activate transcription without affecting its intracellular location or DNA-binding activity. This effect is dependent on a 60-amino-acid region of CREB that contains Ser133 and is termed the kinase-inducible domain (KID)2, which also occurs in the CREB-related CREM-alpha and -beta proteins, although these are transcriptional repressors. Here we show that the KID domain confers a cAMP-inducible increase on the activity of the Q2 activation domain from CREB and the acidic activation domains from the yeast proteins GAL4 and GCN4. Remarkably, it retains this ability even when attached to a separate polypeptide bound to an adjacent site in the promoter. KID may therefore be the first of a new class of conditional activators that work through other promoter-bound factors to stimulate gene expression in response to hormonal stimuli.