995 Clinical Outcomes Following Incomplete Colonoscopy

Introduction

Following incomplete colonoscopy (IC) it is reported that there is up to five-fold increased risk of colorectal cancer. Our aim was to determine the final clinical outcome for patients with a prior IC.

Method

A multi-centre retrospective observational study involving three endoscopy units. All consecutive patients having colonoscopy from over 18 months were analysed. Exclusion criteria included IC was due to obstructing cancer, follow up was not performed due to non-attendance at clinic or investigation and incomplete data set. Electronic notes were analysed to determine patient’s final clinical outcome. All patients were followed up for minimum of six months.

Results

Of the 8,490 colonoscopies, 733 (8.6%) were IC. 86 (11.7%) were excluded. Of the 647 included, 469 (72.4%) were females and 473 (73.1%) has further colonic investigations. Secondary investigations were: CT colonography 169 (35.7%), repeat colonoscopy 161 (34.0%), barium enema 95 (20.1%) and others 48 (10.1%). The repeat colonoscopy group achieved a complete colonoscopy in 111 (68.9%) patients. For those who had further investigations 15 (3.2%) had colorectal cancer and 12 (2.5%) has polyps ≥1cm.

Conclusions

There is significant risk of missing colorectal malignancy and large polyps following IC. Further colonic investigations should be carried out in this cohort of patients.

Patterns of fetal growth in an Asian Indian cohort in the USA

OBJECTIVE

To determine whether a greater proportion of fetuses in an Asian Indian cohort are classified as small for gestational age than would be expected from a normally distributed population.

METHODS

A retrospective analysis of fetal growth pattern and neonatal outcome was conducted among Asian Indian women who were referred to a maternal-fetal medicine center in Park Ridge, IL, USA, for evaluation of fetal growth between January 1, 2012, and December 31, 2013. The primary outcome was an abdominal circumference or estimated weight of lower than the 10th percentile for gestational age according to the Hadlock formula.

RESULTS

Overall, 207 women and 210 fetuses were included. Forty-eight (22.9%) fetuses had an abdominal circumference lower than the 10th percentile. The total number of neonates classified as small for gestational age at delivery was 22 (10.5%), a value indicative of a normally distributed population.

CONCLUSION

Fetal size was smaller than expected among the present Asian Indian cohort, but most neonates were classified as appropriate for gestational age at birth. Population specific growth curves are needed to improve assessment of fetal growth.

Longitudinal evaluation of T1ρ and T2 spatial distribution in osteoarthritic and healthy medial knee cartilage

OBJECTIVE

To investigate longitudinal changes in laminar and spatial distribution of knee articular cartilage magnetic resonance imaging (MRI) T1ρ and T2 relaxation times, in individuals with and without medial compartment cartilage defects.

DESIGN

All subjects (at baseline n = 88, >18 years old) underwent 3-Tesla knee MRI at baseline and annually thereafter for 3 years. The MR studies were evaluated for presence of cartilage defects (modified Whole-Organ Magnetic Resonance Imaging Scoring - mWORMS), and quantitative T1ρ and T2 relaxation time maps. Subjects were segregated into those with (mWORMS ≥2) and without (mWORMS ≤1) cartilage lesions at the medial tibia (MT) or medial femur (MF) at each time point. Laminar (bone and articular layer) and spatial (gray level co-occurrence matrix - GLCM) distribution of the T1ρ and T2 relaxation time maps were calculated. Linear regression models (cross-sectional) and Generalized Estimating Equations (GEEs) (longitudinal) were used.

RESULTS

Global T1ρ, global T2 and articular layer T2 relaxation times at the MF, and global and articular layer T2 relaxation times at the MT, were higher in subjects with cartilage lesions compared to those without lesions. At the MT global T1ρ relaxation times were higher at each time point in subjects with lesions. MT T1ρ and T2 became progressively more heterogeneous than control compartments over the course of the study.

CONCLUSION

Spatial distribution of T1ρ and T2 relaxation time maps in medial knee OA using GLCM technique may be a sensitive indicator of cartilage deterioration, in addition to whole-compartment relaxation time data.

Abstract P3-08-18: Association of tamoxifen use and ovarian aging in patients with invasive or pre-invasive breast cancer

Background: The use of tamoxifen has been shown to delay the recovery of chemotherapy-induced amenorrhea, however the independent impact of long-term endocrine therapy on ovarian aging is not known, and to our knowledge, has never been directly investigated. Understanding the effect of endocrine therapy on ovarian aging will help breast cancer patients of reproductive age make more informed and empowered decisions regarding their treatment. The aim of this study is to explore the relationship between tamoxifen therapy and age onset of menopause.

Methods: We conducted a retrospective cohort study using patients identified through the UCSF Cancer Registry and UCSF SPORE database. Women who were diagnosed with Stage 1-3 invasive or in situ breast cancer between 1985 and 2011, who were premenopausal at the time of diagnosis and who did not receive systemic chemotherapy were included. Patients with recurrent disease and prior ovarian surgery were excluded. Eligibility was confirmed by telephone, and online or paper surveys were distributed to eligible subjects only. Age onset of menopause was the primary endpoint of the study and was defined as the age at which a woman had her last period and no menses for 12 months. Age onset of menopause was assessed through surveys. The primary analysis compared age onset of menopause between subjects who received tamoxifen for any duration and control subjects who never received tamoxifen. Secondary analyses were performed using a Cox proportional hazards model to determine whether duration of tamoxifen exposure and age of tamoxifen initiation impacted age onset of menopause in subjects treated with tamoxifen.

Results: A total of 1137 potential subjects believed to meet eligibility criteria were identified and called, and 649 subjects were reached. Eligibility was confirmed by phone in 340 subjects. A total of 336 subjects consented to participate in the study, and 262 (78%) completed and returned the survey. 227 subjects were included in the primary analysis of which 110 subjects received prior tamoxifen, and 117 subjects received no prior tamoxifen. At the time of the survey, 16.3% vs. 20.2% of patients under age 50 that were exposed and not exposed to tamoxifen entered menopause, respectively. The median age onset of menopause was 50.94 and 51.34 for the tamoxifen and no tamoxifen groups, respectively. The hazard ratio between these groups was 1.077 which was not statistically significant (p = 0.6917). No association (p = 0.55) was found between the duration of tamoxifen use and the age onset of menopause. When controlling for tamoxifen duration, there was no significant difference (p = 0.93) in age onset of menopause between subjects who initiated tamoxifen prior to age 45 and those who initiated at age 45 or older.

Conclusion: These data suggest that tamoxifen alone is not associated with an earlier age onset of menopause, and that tamoxifen use, in the absence of systemic chemotherapy, is unlikely to significantly accelerate ovarian aging.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-08-18.

Combined dysfunctions of immune cells predict nosocomial infection in critically ill patients

BACKGROUND

Nosocomial infection occurs commonly in intensive care units (ICUs). Although critical illness is associated with immune activation, the prevalence of nosocomial infections suggests concomitant immune suppression. This study examined the temporal occurrence of immune dysfunction across three immune cell types, and their relationship with the development of nosocomial infection.

METHODS

A prospective observational cohort study was undertaken in a teaching hospital general ICU. Critically ill patients were recruited and underwent serial examination of immune status, namely percentage regulatory T-cells (Tregs), monocyte deactivation (by expression) and neutrophil dysfunction (by CD88 expression). The occurrence of nosocomial infection was determined using pre-defined, objective criteria.

RESULTS

Ninety-six patients were recruited, of whom 95 had data available for analysis. Relative to healthy controls, percentage Tregs were elevated 6-10 days after admission, while monocyte HLA-DR and neutrophil CD88 showed broader depression across time points measured. Thirty-three patients (35%) developed nosocomial infection, and patients developing nosocomial infection showed significantly greater immune dysfunction by the measures used. Tregs and neutrophil dysfunction remained significantly predictive of infection in a Cox hazards model correcting for time effects and clinical confounders {hazard ratio (HR) 2.4 [95% confidence interval (CI) 1.1-5.4] and 6.9 (95% CI 1.6-30), respectively, P=0.001}. Cumulative immune dysfunction resulted in a progressive risk of infection, rising from no cases in patients with no dysfunction to 75% of patients with dysfunction of all three cell types (P=0.0004).

CONCLUSIONS

Dysfunctions of T-cells, monocytes, and neutrophils predict acquisition of nosocomial infection, and combine additively to stratify risk of nosocomial infection in the critically ill.

Provision of long-acting reversible contraception in HIV-prevalent countries: results from nationally representative surveys in southern Africa

OBJECTIVE

To analyse the current provision of long-acting reversible contraception (LARC) and clinician training needs in HIV-prevalent settings.

DESIGN

Nationally representative survey of clinicians.

SETTING

HIV-prevalent settings in South Africa and Zimbabwe.

POPULATION

Clinicians in South Africa and Zimbabwe.

METHODS

Nationally representative surveys of clinicians were conducted in South Africa and Zimbabwe (n = 1444) to assess current clinical practice in the provision of LARC in HIV-prevalent settings. Multivariable logistic regression was used to analyse contraceptive provision and clinician training needs.

MAIN OUTCOME MEASURE

Multivariable logistic regression of contraceptive provision and clinician training needs.

RESULTS

Provision of the most effective reversible contraceptives is limited: only 14% of clinicians provide copper intrauterine devices (IUDs), 4% levonorgestrel-releasing IUDs and 16% contraceptive implants. Clinicians' perceptions of patient eligibility for IUD use were overly restrictive, especially related to HIV risks. Less than 5% reported that IUDs were appropriate for women at high risk of HIV or for HIV-positive women, contrary to evidence-based guidelines. Only 15% viewed implants as appropriate for women at risk of HIV. Most clinicians (82%), however, felt that IUDs were underused by patients, and over half desired additional training on LARC methods. Logistic regression analysis showed that LARC provision was largely restricted to physicians, hospital settings and urban areas. Results also showed that clinicians in rural areas and clinics, including nurses, were especially interested in training.

CONCLUSIONS

Clinician competency in LARC provision is important in southern Africa, given the low use of methods and high rates of unintended pregnancy among HIV-positive and at-risk women. Despite low provision, clinician interest is high, suggesting the need for increased evidence-based training in LARC to reduce unintended pregnancy and associated morbidities.

Characterization of glioblastoma (GBM) vasculature and protein expression of surrounding tumor cells on single FFPE sections with a multicycle multiplexed in situ immunofluorescent staining technology

2097

Background: GBM is the most common brain tumor in humans and has a dismal prognosis. Although antiangiogenic therapy (bevacizumab) is an option for GBM, there is still unmet need to understand tumor pathophysiology and predictive biomarkers. We built a tissue based multiplexed immunofluorescent assays and developed algorithms to identify and quantify tumor vasculature, that enabled quantification, visualization, and colocalization of multiple protein in surrounding tumor cells at single cell and subcellular levels. This assay provides unique opportunity to explore tumor heterogeneity of tissue morphology and their relationships to vasculature, and is a novel tool for biomarker and treatment discovery. Methods: Tissue micro arrays (TMAs) were constructed from 141 GBM patients. Fluorescent dye labeled antibodies against 18 biomarkers were sequentially applied on single sections of these TMAs. Metrics were built to identify vessels, quantify distance of tumor cells to vessels, and analyze expression profiles of biomarkers, including signaling molecules in EGFR, PI3K/AKT, TGF-beta pathways, and hypoxia marker Glut1, in proximity to blood vessels. Results: CD31 was successfully used to identify blood vessels in GMB. Vessel segmentation and quantification were performed on all of the images. Biomarker profiling in the context of blood vessels demonstrated different patterns in close proximity to vessels, with some biomarkers showing increased levels (e.g. SMA, EGFR, pS6), some showing decreased levels (e.g. p4EBP), and others remain the same (FOXO3a, S6). Quantification of biomarkers showed heterogeneous expression within the same sample and across the cohort. In addition, co-localization of the above markers was visualized and demonstrated on single cell and subcellular levels. Conclusions: We were able to use a novel fluorescent multiplexing technology (MultiOmyx) to study GBM biology. This technology allowed the simultaneous analyses of multiple biomarkers of GBM, and provides new insights on the relationship of markers to each other, tumor heterogeneity and angiogenesis.

Multiplexed IHC analysis to enable Hodgkin lymphoma differential diagnosis on a single slide

e19536

Background: Routine diagnosis of classical Hodgkin lymphoma is performed with a panel of immunohistochemistry markers to evaluate the biomarker expression profile of the relatively rare Hodgkin cells. One of the key challenges of this technique is that serial immunostains are used and hence it can be difficult or impossible to locate the same Hodgkin cell on adjacent slides. Given the rarity of the Hodgkin cells coupled with the number of markers that are needed for a definitive diagnosis, we developed a new technique in which a single patient slide is multiplexed with nine different antibodies . Methods: One FFPE tissue section from 11 cases was probed for the following nine biomarkers: CD30, CD15, CD45, Pax5, CD20, CD79a, OCT2, Bob1, and CD3. An initial 10x whole slide fluorescent image of CD30 was acquired and presented to the pathologist who based on this staining selected regions of interest for higher magnification (40x) imaging of the CD30 and the other antibodies. The fluorescent images acquired were processed for interpretation using an in-house developed viewing tool. The pathologist was able to view each biomarker as a standard grayscale, monochromatic image, an overlay of two or more biomarkers, or as a virtually created molecular DAB image. Results: A correct diagnosis of classical Hodgkin lymphoma vs. other was able to be made using the MultiOmyx platform in all cases. Subjectively, the pathologist noted that the novel methodology allowed for a significantly more confident assessment of marker expression on the Hodgkin cells in the seven cases of classical Hodgkin lymphoma, eliminating many issues of staining ambiguity and allowing recognition of subtle nuances of staining intensity in the Hodgkin cells. The CD30+ cells in the four other cases, three cases of B-cell lymphoma and one case of lymphocyte predominance Hodgkin lymphoma, showed a B-cell profile that was distinguishable from the classical Hodgkin cell phenotype. Conclusions: This new method of fluorescent multiplexing on a single tissue section allows more accurate interpretation of the biomarker expression profile on the same Hodgkin cell. It is likely that this paradigm can be expanded to a greater range of challenging cases in hematopathology.

Abstract P3-05-06: Automated analysis of Her2 FISH using combined Immunofluorescence and FISH signals

Introduction: Qualifying patients for Her2 targeted therapy is currently done by detecting Her2 protein overexpression or gene amplification using immunohistochemistry and/or FISH. We have recently developed a method for detecting both signals on the same tissue section allowing direct correlation of protein expression and gene copy number on a cell by cell basis. Accurate assessment of Her2 gene copy number is critical and can pose a challenge due to tumor heterogeneity. This paper reports the accuracy of a proprietary FISH dot counting algorithm on a cell-by-cell basis, potentially allowing analysis of thousands instead of dozens of tumor cells.

Method: Automatic FISH signal counts were compared to manual counts of 888 cells selected from 19 invasive ductal breast carcinoma samples exhibiting varying degrees of Her2 expression collected between June 2011 and March 2012. Tissue sections (4 µm) were mounted on positively charged slides, baked and processed through deparaffinization, rehydration and antigen retrieval, then stained for immunofluorescence (IF) using Cy5 labeled Her2 and Cy3 labeled cytokeratin antibodies, counterstained with DAPI, and imaged using InCell 2000 analyzer with GE-proprietary acquisition and processing software. Images were collected at 10x magnification and digitally stitched to span the entire tissue section. A pathologist then selected separate tumor and adjacent normal epithelium regions for subsequent imaging at 40x magnification. Slides were subsequently processed for FISH by pepsin digestion and then subjected to FISH by using PathVysion kit (Abbott Molecular, Des Plaines, IL). After hybridization and subsequent high stringency washes, samples were DAPI stained and mounted for microscopy. Samples were imaged at 40x at the same regions recorded for 40x IF acquisition, using filtersets appropriate for FISH fluorophores and DAPI.

A proprietary automated processing algorithm was used to analyze combined IF and FISH signals and derive case specific Her2 score from the tumor and/or adjacent normal epithelium. Cell-level dot counting accuracy was assessed using two metrics comparing automated counts to manual counts: cell classification agreement, where a normal cell was defined as having 3 or less Her2 and Cep17 dots; and dot-counting match, where a difference of more than 20% in absolute counts was considered an error.

Result: Our automatic results gave an overall cell-by-cell classification agreement of 88% (range 71% to 98% by case). Combining classification agreement and counting match, our algorithm gave an overall accuracy of 81% (range 63% to 97% by case). Restricting to tumor tissues (as judged by pathologist review of IF) classification agreement and accuracy were 84% and 72%, respectively.

Conclusion: The observed variability in algorithm performance between the different cases was due to the fact that error root causes were case dependent. For instance, the main cause of over-counting errors was image noise and artifacts. On the other hand, the main cause of under-counting was low image contrast, especially in highly amplified cases. These results are an early indication of the promise of automatic dot counting applied to breast cancer slides multiplexed for Her2 IF and FISH.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P3-05-06.

Equivalence and precision of knee cartilage morphometry between different segmentation teams, cartilage regions, and MR acquisitions

OBJECTIVE

To compare precision and evaluate equivalence of femorotibial cartilage volume (VC) and mean cartilage thickness over total area of bone (ThCtAB.Me) from independent segmentation teams using identical Magnetic Resonance (MR) images from three series: sagittal 3D Dual Echo in the Steady State (DESS), coronal multi-planar reformat (DESS-MPR) of DESS and coronal 3D Fast Low Angle SHot (FLASH).

DESIGN

Nineteen subjects underwent test-retest MR imaging at 3 T. Four teams segmented the cartilage using prospectively defined plate regions and rules. Mixed models analysis of the pooled data were used to evaluate the effect of acquisition, team and plate on precision and Pearson correlations and mixed models were used to evaluate equivalence.

RESULTS

Segmentation team differences dominated measurement variability in most cartilage regions for all image series. Precision of VC and ThCtAB.Me differed significantly by team and cartilage plate, but not between FLASH and DESS. Mean values of VC and ThCtAB.Me differed by team (P < 0.05) for DESS, FLASH and DESS-MPR. FLASH VC was 4-6% larger than DESS in the medial tibia and lateral central femur, and FLASH ThCtAB.Me was 5-6% larger in the medial tibia, but 4-8% smaller in the medial central femur. Correlations between DESS and FLASH for VC and ThCtAB.Me were high (r = 0.90-0.97), except for DESS vs FLASH medial central femur ThCtAB.Me (r = 0.81-0.83).

CONCLUSIONS

Cartilage morphology metrics from different image contrasts had similar precision, were generally equivalent, and may be combined for cross-sectional analyses if potential systematic offsets are accounted for. Data from different teams should not be pooled unless equivalence is demonstrated for cartilage metrics of interest.

Flow residence time and regions of intraluminal thrombus deposition in intracranial aneurysms

Thrombus formation in intracranial aneurysms, while sometimes stabilizing lesion growth, can present additional risk of thrombo-embolism. The role of hemodynamics in the progression of aneurysmal disease can be elucidated by patient-specific computational modeling. In our previous work, patient-specific computational fluid dynamics (CFD) models were constructed from MRI data for three patients who had fusiform basilar aneurysms that were thrombus-free and then proceeded to develop intraluminal thrombus. In this study, we investigated the effect of increased flow residence time (RT) by modeling passive scalar advection in the same aneurysmal geometries. Non-Newtonian pulsatile flow simulations were carried out in base-line geometries and a new postprocessing technique, referred to as "virtual ink" and based on the passive scalar distribution maps, was used to visualize the flow and estimate the flow RT. The virtual ink technique clearly depicted regions of flow separation. The flow RT at different locations adjacent to aneurysmal walls was calculated as the time the virtual ink scalar remained above a threshold value. The RT values obtained in different areas were then correlated with the location of intra-aneurysmal thrombus observed at a follow-up MR study. For each patient, the wall shear stress (WSS) distribution was also obtained from CFD simulations and correlated with thrombus location. The correlation analysis determined a significant relationship between regions where CFD predicted either an increased RT or low WSS and the regions where thrombus deposition was observed to occur in vivo. A model including both low WSS and increased RT predicted thrombus-prone regions significantly better than the models with RT or WSS alone.

Pre-radiographic MRI findings are associated with onset of knee symptoms: the most study

OBJECTIVE

Magnetic resonance imaging (MRI) has greater sensitivity to detect osteoarthritis (OA) damage than radiographs but it is uncertain which MRI findings in early OA are clinically important. We examined MRI abnormalities detected in knees without radiographic OA and their association with incident knee symptoms.

METHOD

Participants from the Multicenter Osteoarthritis Study (MOST) without frequent knee symptoms (FKS) at baseline were eligible if they also lacked radiographic features of OA at baseline. At 15 months, knees that developed FKS were defined as cases while control knees were drawn from those that remained without FKS. Baseline MRIs were scored at each subregion for cartilage lesions (CARTs); osteophytes (OST); bone marrow lesions (BML) and cysts. We compared cases and controls using marginal logistic regression models, adjusting for age, gender, race, body mass index (BMI), previous injury and clinic site.

RESULTS

36 case knees and 128 control knees were analyzed. MRI damage was common in both cases and controls. The presence of a severe CART (P=0.03), BML (P=0.02) or OST (P=0.02) in the whole knee joint was more common in cases while subchondral cysts did not differ significantly between cases and controls (P>0.1). Case status at 15 months was predicted by baseline damage at only two locations; a BML in the lateral patella (P=0.047) and at the tibial subspinous subregions (P=0.01).

CONCLUSION

In knees without significant symptoms or radiographic features of OA, MRI lesions of OA in only a few specific locations preceded onset of clinical symptoms and suggest that changes in bone play a role in the early development of knee pain. Confirmation of these findings in other prospective studies of knee OA is warranted.

Younger children with MS have a distinct CSF inflammatory profile at disease onset

BACKGROUND

The clinical and MRI presentation differs between earlier- and later-onset pediatric multiple sclerosis (MS), whereas the effect of age on the CSF inflammatory profile is unknown and may contribute to delayed diagnosis.

OBJECTIVES

To compare the CSF cellular and immunoglobulin G (IgG) profiles between earlier- and later-onset pediatric MS.

METHODS

We queried the databases of 6 pediatric MS centers for earlier-onset (onset <11 years) and later-onset (> or = 11 and <18 years) patients with MS or clinically isolated syndrome who underwent CSF analysis within the first 3 months of presentation (observational study). We compared CSF white blood cell (WBC) differential count, IgG index, and IgG oligoclonal bands between age groups.

RESULTS

We identified 40 earlier-onset (mean age at onset = 7.2 +/- 2.7 years, 60% females) and 67 later-onset pediatric MS patients (15.1 +/- 1.7 years, 63% females). Although WBC count tended to be higher in earlier-onset patients (median = 9/mm(3) [0-343] vs 6 [0-140], p = 0.15), they had a lower proportion of lymphocytes (70% [0-100] vs 93% [0-100] of WBCs, p = 0.0085; difference = +3% per 1-year increase of age, p = 0.0011) and higher proportion of neutrophils than later-onset patients (0.5% [0-75] vs 0% [0-50] of WBCs, p = 0.16; difference = -1% per 1-year increase of age, p = 0.033). In earlier-onset disease, fewer patients had an elevated IgG index than in the later-onset group (35% vs 68% of patients, p = 0.031).

CONCLUSION

Age modifies the CSF profile at pediatric multiple sclerosis (MS) onset, which may mislead the diagnosis. Our findings suggest an activation of the innate rather than the adaptive immune system in the earlier stages of MS or an immature immune response.

Divergent transcriptomic responses to aryl hydrocarbon receptor agonists between rat and human primary hepatocytes

Toxicogenomics has great potential for enhancing our understanding of environmental chemical toxicity, hopefully leading to better informed human health risk assessments. This study employed toxicogenomic technology to reveal species differences in response to two prototypical aryl hydrocarbon receptor (AHR) agonists 2,3,7,8-tetrachlorodibenzo-p-dioxin and the polychlorinated biphenyl (PCB) congener PCB 126. Dose-responses of primary cultures of rat and human hepatocytes were determined using species-specific microarrays sharing over 4000 gene orthologs. Forty-seven human and 79 rat genes satisfied dose-response criteria for both chemicals and were subjected to further analysis including the calculation of the 50% effective concentration and the relative potency (REP) of PCB 126 for each gene. Only five responsive orthologous genes were shared between the two species; yet, the geometric mean of the REPs for all rat and human modeled responsive genes were 0.06 (95% confidence interval [CI]; 0.03-0.1) and 0.002 (95% CI; 0.001-0.005), respectively, suggesting broad species differences in the initial events that follow AHR activation but precede toxicity. This indicates that there are species differences in both the specific genes that responded and the agonist potency and REP for those genes. This observed insensitivity of human cells to PCB 126 is consistent with more traditional measurements of AHR activation (i.e., cytochrome P450 1A1 enzyme activity) and suggests that the species difference in PCB 126 sensitivity is likely due to certain aspects of AHR function. That a species divergence also exists in this expanded AHR-regulated gene repertoire is a novel finding and should help when extrapolating animal data to humans.

Chondrocyte interactions with porous titanium alloy and calcium polyphosphate substrates

Chondrocytes maintain their phenotype and form cartilagenous tissue when cultured on calcium polyphosphate (CPP) or titanium alloy (Ti alloy), porous three-dimensional materials. To understand how these materials may influence chondrocyte phenotype and matrix synthesis, the early interactions of cultured cells with CPP and titanium alloy were examined. These were compared to chondrocytes grown in monolayer culture on tissue culture polystyrene, conditions in which cultured chondrocytes dedifferentiate and do not form cartilagenous tissue. Scanning electron microscopy of cells up to 72 h in culture showed that bovine chondrocytes on CPP, Ti alloy, and polystyrene were an admixture of round and spread cells. The spread cells on CPP and titanium alloy were not entirely flattened but maintained a polygonal shape. In contrast, spread chondrocytes in monolayer culture were flatter and significantly larger, a difference that was maintained even in the absence of serum. All cells cultured on CPP and Ti alloy exhibited subcortical ring-like distribution of actin filaments whereas the flattened cells on polystyrene showed actin filaments distributed throughout the cytoplasm. Cells on CPP and Ti alloy synthesized significantly less collagen and proteoglycans than cells cultured on polystyrene at 72 h of culture. In summary the cells on the porous three-dimensional materials differed from those on polystyrene in terms of cell morphology and size, actin cytoskeleton organization, and synthesis of selected matrix macromolecules. The data suggests that CPP and titanium alloy may mediate their effect by limiting cell spreading in part by favoring the maintenance of a ring-like actin distribution.

CSF tau protein phosphorylated at threonine 231 correlates with cognitive decline in MCI subjects

In this longitudinal study of 77 patients with mild cognitive impairment (MCI), the authors analyzed whether levels of tau protein phosphorylated at threonine 231 (p-tau(231)) in CSF correlate with progression of cognitive decline. High CSF p-tau(231) levels at baseline, but not total tau protein levels, correlated with cognitive decline and conversion from MCI to AD. Independently, old age and APOE-epsilon 4 carrier status were predictive as well. Our data indicate that an increased p-tau(231) level is a potential risk factor for cognitive decline in patients with MCI.

Venous gangrene of lower extremities and Staphylococcus aureus sepsis

This is a study of the venous gangrene of lower extremities and Staphylococcus aureus sepsis. We report on a premature infant who developed phlegmasia cerulea dolens (PCD) in both lower extremities in association with S. aureus sepsis, resulting in gangrene of the right foot. Non-pitting edema and cyanosis of the digits of the right lower extremity were noted 48 hours after hypotension and severe shock due to S. aureus sepsis. Intravenous antibiotics, isotonic fluids, and heparin were administered. Twenty-four hours later, edema and ischemic changes of the first and fifth left toes were also noted. Doppler flow study showed flow signals in both right and left popliteal arteries. However, there were no Doppler signals in neither right nor left popliteal vein. Emergency fasciotomies were performed on both lower limbs. The progression of the gangrene was limited to the right foot. There was complete resolution of PCD in both lower extremities. To the best of our knowledge, the association of S. aureus sepsis with PCD and venous gangrene in an infant has not been reported previously. This case illustrates the need for early recognition of PCD and aggressive intervention.

Template mixture models for direct cortical electrical interference data

This paper introduces a statistical approach for high-level spatial analysis when there is little prior information about the shape or location of the region of interest in the underlying image and limited spatial resolution of the available data. Our work was motivated by a functional brain mapping technique called direct cortical electrical interference (DCEI) that gives binary observations at multiple sites throughout the brain. We estimate an underlying, binary spatial response function using a mixture of an unknown number of simple geometrical shapes (e.g. circles) with unknown centers and sizes to be estimated. Inference is made using reversible jump Markov chain Monte Carlo. The approach is illustrated with simulated examples and a real example with DCEI data.

Biochemical and functional characterization of intercellular adhesion and gap junctions in fibroblasts

Despite their significance in wound healing, little is known about the molecular determinants of cell-to-cell adhesion and gap junctional communication in fibroblasts. We characterized intercellular adherens junctions and gap junctions in human gingival fibroblasts (HGFs) using a novel model. Calcein-labeled donor cells in suspension were added onto an established, Texas red dextran (10 kDa)-labeled acceptor cell monolayer. Cell-to-cell adhesion required Ca(2+) and was >30-fold stronger than cell-to-fibronectin adhesion at 15 min. Electron micrographs showed rapid formation of adherens junction-like structures at approximately 15 min that matured by approximately 2-3 h; distinct gap junctional complexes were evident by approximately 3 h. Immunoblotting showed that HGF expressed beta-catenin and that cadherins and connexin43 were recruited to the Triton-insoluble cytoskeletal fraction in confluent cultures. Confocal microscopy localized the same molecules to intercellular contacts of acceptor and donor cells. There was extensive calcein dye transfer in a cohort of Texas red dextran-labeled cells, but this was almost completely abolished by the gap junction inhibitor beta-glycyrrhetinic acid and the connexin43 mimetic peptide GAP 27. This donor-acceptor cell model allows large numbers (>10(5)) of cells to form synchronous cell-to-cell contacts, thereby enabling the simultaneous functional and molecular studies of adherens junctions and gap junctions.

Can we improve the uptake of gastroscopy in the population at risk for gastric cancer? The effect of home letter information

The poor outlook for gastric cancer in Britain is largely due to late diagnosis. Earlier diagnosis will require both easy access to endoscopy and increased public awareness of dyspeptic symptoms. We used information by personal letter to encourage reporting of potentially significant symptoms in patients over 40 years of age. The aim of this study was to measure the acceptability and effect on gastroscopy rates of home letter information. Patients over 40 registered with 12 general practices were used in the study (practice population 80,000). Patients over 40 from another nine practices (practice population 46,500) acted as controls. A letter encouraging consultation for new dyspeptic symptoms was sent to all study subjects. Gastroscopy rates were compared in both study and control populations. Questionnaires on symptoms were sent to 500 study subjects. The principal outcome measure was the gastroscopy rate in people over 40 in both populations, before and during the intervention. The gastroscopy rate was 23% higher in the study than in the control population during the study (3.32 vs. 2.7%, P = 0.00016, chi 2 = 14.25). Gastroscopy uptake increased by 85% from 1991/2 to 1993/4 in the study group and by 34% in the control group (chi 2 = 14.02, P = 0.00018). Thirty-one per cent of questionnaire respondents had dyspeptic symptoms; only 3% had 'significant' symptoms of between 2 and 52 weeks duration. Home letters are an acceptable and efficient method of increasing gastroscopy uptake in dyspeptic patients over 40.

Interleukin 1-induced calcium signalling in chondrocytes requires focal adhesions

The cytokine interleukin 1 (IL-1) is an important mediator of connective-tissue destruction in arthritic joints but the mechanisms by which IL-1 mediates signal transduction in chondrocytes is poorly understood. Previous results have indicated that IL-1 receptors co-localize with focal adhesions [Qwarnstrom, Page, Gillis and Dower (1988) J. Biol. Chem. 263, 8261-8269], discrete adhesive domains of cells that function in cell attachment and possibly in signal transduction. We have determined whether focal adhesions restrict IL-1-induced Ca2+ signalling in primary cultures of bovine chondrocytes. In cells grown for 24 h on fibronectin, the basal intracellular Ca2+ ion concentration ([Ca2+]i) was 100+/-3 nM. Optimal increases of [Ca2+]i above baseline were induced by 10 nM IL-1 (183+/-30 nM above baseline). There was no significant difference between cells plated on fibronectin or type II collagen (P>0.2; 233+/-90 nM above baseline). Ca2+ transients were significantly decreased by the inclusion of 0.5 mM EGTA in the bathing buffer (74+/-11 nM above baseline), and 1 microM thapsigargin completely blocked Ca2+ transients. Cells plated on poly-(l-lysine) or suspended cells showed no Ca2+ increases, whereas cells grown on fibronectin exhibited IL-1-induced Ca2+ responses that corresponded temporally to the time-dependent cell spreading after plating on fibronectin. Cells plated on poly-(l-lysine) and incubated with fibronectin-coated beads exhibited vinculin staining in association with the beads. In identical cell preparations, IL-1 induced a 136+/-39 nM increase of [Ca2+]i above baseline in response to 10 nM IL-1beta. There were no IL-1-induced Ca2+ increases when cells on poly-(l-lysine) were incubated with fibronectin-coated beads for only 15 min at 37 degrees C, in cells maintained for 3 h at 4 degrees C, in cells incubated with BSA beads for 3 h at 37 degrees C, or in cells pretreated with cytochalasin D. Labelling of IL-1 receptors with 125I-IL-1beta showed 3-fold more specific labelling of focal adhesion complexes in cells incubated with fibronectin-coated beads compared with cells incubated with BSA-coated beads, indicating that IL-1 receptor binding or the number of IL-1 receptors was increased in focal adhesions. These results indicate that, in chondrocytes, IL-1-induced Ca2+ signalling is dependent on focal adhesion formation and that focal adhesions recruit IL-1 receptors by redistribution in the cell membrane.

Single cell analysis of intracellular osteopontin in osteogenic cultures of fetal rat calvarial cells

Osteopontin (OPN), a major component of the bone matrix, is expressed at different stages of bone formation. To determine possible relationships between OPN expression and stages of osteogenic cell differentiation, we have performed single cell analyses of intracellular OPN in early (proliferating), subconfluent (differentiating), and mature (mineralizing) cultures of fetal rat calvarial cells (FRCC) using a combination of flow cytometry and confocal microscopy. At each culture stage, a high proportion (60-98%) of cells were immunoreactive for OPN (OPN+ve). Each of these populations also included a small proportion of OPN-ve cells which were characterized by their small size, low granularity, high proliferative capacity, and enhanced osteogenic potential. The OPN+ve cells displayed two distinct patterns of intracellular immunostaining: a perinuclear distribution typical of secreted proteins and a perimembrane distribution in which patches of OPN were concentrated at the cell surface. Perimembranous staining predominated in migrant cells, which contained greater than tenfold higher levels of OPN than nonmigrant cells as separated in a Boyden chamber. When cell proliferation was high (day 2), most cells were OPN + ve. At all culture stages the intensity of OPN staining was increased as cells progressed through the cell cycle. As cells differentiated and started to form matrix (days 4 and 6), the mean cell expression of OPN was also increased (fourfold), independent of changes in total cell protein. However, despite the association of OPN with osteogenic cells, we were surprised to find that a high proportion (60%) of fetal skin fibroblasts were also immunoreactive for OPN. The expression of OPN by these cell populations was confirmed by RT-PCR, and a strong correlation was observed between the quantitative flow cytometry data and Western blot analysis of cell extracts in which the high and low phosphorylated isoforms of OPN were observed. These studies, therefore, have identified several phenotypes in FRCC cultures that are based on OPN expression: small OPN-ve cell populations enriched in osteogenic precursors, differentiating osteogenic cells that synthesize and secrete OPN, and migrating stromal cells characterized by a perimembranous OPN staining pattern.

Excitatory effect of morphine and opioid peptides in the rat isolated colon

Morphine and the opioid peptides cause isolated segments of rat colon to contract and relax rhythmically. This study re-examines two hypotheses to explain this phenomenon: Release of 5-hydroxytryptamine (5-HT)/acetylcholine by morphine or inhibition of a tonically active non-adrenergic, non-cholinergic (NANC) inhibitory mechanism. Rhythmic contractions induced by morphine (5 x 10(-6) M) were naloxone sensitive (10(-6) M) but unaffected by methysergide (10(-6) M), atropine (10(-6) M) or pretreatment of rats with p-chlorophenylalanine (200 mg kg-1 i.p. for four days) which lowered the 5-HT level in the colon from 3.73 +/- 0.83 mg g-1 in controls to 0.41 +/- 0.06 mg g-1 (P less than 0.001). The pattern of rhythmic contractions produced by morphine was unlike those produced by 5-HT (5 x 10(-6) M), acetylcholine (5 x 10(-6) M) or potassium chloride (30 mM). Tetrodotoxin (10(-6) M), apamin (10(-8) M), clonidine (2 x 10(-8) M), phentolamine (10(-5) M) or oxprenolol (10(-5) M) caused rhythmic contractions which were unaffected by naloxone. Clonidine contractions were inhibited by yohimbine (10(-7) M) but not by prazosin (10(-6) M). Electrical field stimulation at the peak of a contraction induced by morphine, apamin or clonidine, produced an inhibitory response which was unaffected by atropine, phentolamine, propranolol and guanethidine (all 10(-5) M). It persisted in colon segments from the rats with reserpine or 6-hydroxydopamine. These results suggest that neither the 5-HT/acetylcholine hypothesis nor inhibition of the NANC mechanism adequately explains the excitatory effect of morphine in the rat colon.

Pathological study in a female carrier of choroideremia

We present the pathological findings in one eye of a 68-year-old woman with choroideremia. There was widespread malformation of the outer receptor segments. A second retinal finding was patches of atrophy, involving loss of the retinal outer cell layer. The pigment epithelium was intact, although there were areas showing depigmentation of the cells. The choriocapillaris was present. The findings suggest that the primary defect in choroideremia lies at the retina-pigment epithelium interface. Possible mechanisms are discussed.

Recurrent corneal erosion, microcystic epithelial dystrophy, map configurations and fingerprint lines in the cornea

A 45-year-old lady presented with a recurrent corneal erosion. On closer examination, she was found to have epithelial microcysts and fingerprint dystrophy. Pathologic material from the affected cornea showed microcysts, protrusions of basement membrane and evidence of poor adhesion between the basement membrane and the epithelial cells, as well as between the epithelial cells themselves. The case demonstrated the clinical and pathologic features of recurrent corneal erosion, microcystic disease and fingerprint dystrophy of the cornea, together with the pathologic findings of map dystrophy. The authors suggest that these four diseases are various expressions of a clinicopathologic entity, epithelial basement membrane corneal dystrophy. A pathologic explanation for recurrent corneal erosion is apparent.

Effects of 30% intestinal resection on whole population cell kinetics of mouse intestinal epithelium

The intestine remaining after resection undergoes a well known compensatory response. Crypts and villi grow in size, and the number of proliferating cells in a crypt increases. The crypt labeling index, however, is unchanged, which is thought to suggest that the growth fraction also remains unchanged and hence that the system is enlarged, but otherwise the new steady-state is similar to that of the controls. It is also generally accepted that no new crypts or villi are added to the adapting bowel. In this study we applied recently developed tools to study the response of the intestinal epithelium as a whole. Thus, the effects of 30% intestinal resection on whole population cell kinetics were determined by using flow cytometry, Coulter particle counting, and simple morphometric techniques. In addition to the classic response, we found an increase in the rate of crypt production, which was due mainly to a shorter crypt replication cycle. Thus, new crypts were produced at a faster rate in the resected animals than in the transected controls. This resulted in an expansion of the crypt cell population in the epithelium following resection. There was a corresponding expansion of the cycling cell population and thus an increase in the growth fraction of the resected epithelium. We conclude that for the crypt population, the classic story is correct with the exception that new crypts are added to the epithelium after resection. However, for the epithelium as a whole, the classic story is misleading as there appears to be an increase in the growth fraction of the epithelium after intestinal resection.

Corneal changes in Fabry's disease: a clinico-pathologic case report of a heterozygote

Fabry's disease is an X-linked recessive inborn error of metabolism, caused by a deficiency of alpha galactosidase A. This report describes a heterozygote patient with multiple system problems diagnosed eventually as Fabry's disease by the ocular findings. The clinical diagnosis was confirmed by enzymatic assay. Our report emphasizes: The variability of the non-ocular manifestations in the heterozygote of Fabry's disease. The diagnosis of Fabry's disease in our patient was made by the ophthalmologist. The ultra-structural changes in the cornea and conjunctiva of the heterozygote confirm those reported in the literature; in addition we describe changes in the goblet cells. The clinical and ultra-structural similarities of the deposits in Fabry's disease, Chloroquin keratopathy and Amiodarone keratopathy are striking and will be discussed.

Amiodarone-induced ultrastructural changes in human eyes

Ocular observations in a series of 100 patients treated with amiodarone, along with the pathological changes observed in the eye tissues of two patients treated with this drug, are described in this paper. In the latter two patients intracytoplasmic membrane-bound lamellar bodies similar to myelin were observed by electron microscopy not only in the corneal epithelium and fibroblasts, the conjunctiva and the lens, but also in the corneal endothelium, the iris, the ciliary body, the choroid and the retina. It is suggested that patients taking amiodarone in high dosage for long periods have their eyes and retinal function monitored.

Ultrastructural changes in the cornea and conjunctiva of a heterozygous woman with Fabry's disease

Heterozygous females with Fabry's disease show a typical whorled pattern in the corneal epithelium. The patient presented in this paper also had symptoms of polymyositis, necrotizing vasculitis and angiokeratomas. The diagnosis was made from the corneal changes. Electron microscopy revealed intracytoplasmic electron-dense deposits made up of lamellar stacks of uniform periodicity similar to myelin. These were present not only in the corneal epithelium but also in the epithelium, goblet cells, endothelium and mural cells of blood vessels in the conjunctiva. The material in the goblet cells may account for the known presence of ceramide trihexoside in the tears.

Colour vision in long-standing diabetes mellitus

In 12 long-standing insulin-dependent diabetics with background diabetic retinopathy their 100-hue colour vision scores were positively related to the degree of retinopathy and negatively to fasting blood glucose levels. However, the 100-hue colour vision scores and types were not significantly different from those of normal subjects matched for age, sex, and social class.

Pathological and surgical examination of the handling of the lacerated eyeball

A survey of 85 lacerated eyeballs pointed to six elements that had led to destruction of the globe: poor wound closure, hypotony, hemorrhage, lens remnants, fibrosis and antigen exposure. Guidelines for the repair of such globes were established on the basis of the pathological findings. The techniques necessitate great care and require the use of a microscope, a vitreous aspiration cutter and fine sutures. Adequate time must be set aside for the surgery, since anything less than careful and complete repair can lead to disaster. The quality of the primary repair is likely to be what defines the excellence of the final result.

Amiodarone-induced cornea verticillata

Among 37 patients treated with amiodarone, an antiarrhythmic drug, a typical keratopathy developed in 35, none of whom had ocular complaints. The keratopathy resembled that seen with Fabry's disease and chloroquine use, as did the membrane-bound lamellar bodies detected by electron microscopy in all layers of the corneal epithelium in the one patient with marked keratopathy in whom a corneal biopsy was performed; membrane-bound bodies, mostly granular, were also noted within this patient's stromal keratocytes. The possible pathogenesis of the keratopathy as a type of drug-induced lipidosis is discussed.

Distribution of silver in the eyes and plasma proteins of the albino rat

Albino rats were given a 0.25% solution of silver nitrate to drink for 10 weeks, then were divided into two groups. One group continued to drink the solution for an additional 6 months, while the other group was given water to drink for an additional 12 months. The ingestion of silver nitrate retarded the growth of the rats and eventually caused their death. The rats regained weight and appeared to grow normally when the silver nitrate regimen was withdrawn. Radioactive silver in the plasma was found to be almost exclusively in a single electrophoretic protein band. Examination of the rats' eyes by electron microscopy showed deposits of silver particles in Bruch's membrane, the basement membranes of the choriocapillaris and the ciliary processes, and the stroma of the choroid and ciliary processes. The number and size of the particles increased with continued ingestion of silver but decreased if the silver regimen was withdrawn after the initial 10 weeks of ingestion. Fine particles of silver were still present 12 months after the end of the ingestion of silver nitrate. At no time were silver particles seen in the basement membranes or endothelial cells of the retinal capillaries or within the cytoplasm of the pigment epithelium or the epithelial cells of eh ciliary processes.