OP0223 DISTINGUISHING OSTEOARTHRITIS AND RHEUMATOID ARTHRITIS SYNOVIUM WITH MACHINE LEARNING USING AUTOMATED CELL DENSITY AND PATHOLOGIST SCORES

Background

Joint damage in the knee can be severe in both rheumatoid arthritis (RA) and osteoarthritis (OA) such that total knee replacement (TKR) is often the only management option. Pathological assessment of the extent or type of synovial tissue inflammation from joint explants or biopsies can be useful. However, an ongoing challenge in using semi-quantitative assessments of synovitis is the disagreement between human pathologist scores of the same sample. We previously developed and validated a computer vision algorithm to automatically count each cell nucleus in an H&E-stained synovial whole slide image and yield a value of cell density, defined as mean nuclei count per mm2 of tissue1.

Objectives

We sought to develop methods to distinguish OA from RA based on machine learning analysis of histologic features on H&E-stained synovial tissue samples.

Methods

We measured 14 pathologist-scored histology features (137 RA and 152 OA patients) and computer vision quantified cell density (60 RA and 147 OA patients) in H&E stained synovial tissue samples from total knee replacement arthroplasty explants. A random forest model was trained using disease state (OA vs RA) as classifier and histology features and/or cell density as inputs, and feature importance scores for the model were calculated.

Results

Synovium from patients with RA exhibited increased lymphocytic inflammation, lining hyperplasia, neutrophils, detritus, plasma cells, Russell bodies, binucleate plasma cells, sub-lining giant cells, synovial lining giant cells, and fibrin (all p<0.001), while synovium from patients with OA had increased mast cells and fibrosis (both p<0.001). Fourteen pathologist-scored features allowed for discrimination between RA and OA samples, producing a macro-averaged area under the receiver operating curve (AUC) of 0.85. This discriminatory ability was comparable to that of the computer vision score of cell density alone (AUC = 0.88). Combining the pathologist scores with the cell density metric improved the discriminatory power of the model (AUC = 0.91). The three most important features in this combined model were mast cells followed by cell density and fibrosis (Figure 1). AUC values for each individual feature are provided in Table 1. The optimal cell density threshold to distinguish RA from OA synovium was 3,400 cells per mm2, which yielded a sensitivity of 0.82 and specificity of 0.82.

Table 1.

Area under receiver operating characteristic curves (AUC) of the synovial features in distinguishing RA and OA patients

FeatureAUCAutomated Cell Density0.88Fibrosis0.84Mast cells0.80Lining hyperplasia0.78Lymphocytic inflammation0.69Fibrin0.68Plasma cells0.66Detritus0.64Binucleate plasma cells0.60Neutrophils0.60Synovial giant cells0.58Sub-lining giant cells0.57Russell bodies0.56Germinal centers0.51Mucoid change0.50Figure 1.

Importance of synovial features in distinguishing RA and OA synovium

Feature importance scores for supervised machine learning model including all 14 pathology scores and the computer vision-generated cell density.

Conclusion

H&E-stained images of RA and OA TKR explant synovium are distinct. We identified cell density, mast cells and fibrosis as the three most important features for making this distinction, with RA being characterized by increased cell density, low mast cells, and low fibrosis. Cell density greater than 3400 per mm2 of tissue yields a sensitivity of 0.82 and a specificity of 0.82 for distinguishing RA from OA. In the future, this can have clinical and research applications as this technique removes the requirement for subjective selection of a certain field of interest, is reproducible, and is scalable as it does not require technical expertise of a pathologist.

References

[1]Guan S, Mehta B…Orange DE. Rheumatoid Arthritis Synovial Inflammation Quantification Using Computer Vision. ACR Open Rheumatology. 2022 Jan 10;acr2.11381.

Acknowledgements

This work was supported by the C. Ronald MacKenzie Young Scientist Endowment Award, the Leon Lowenstein Foundation, and the Kellen Scholar Award supported by the Anna Marie and Stephen Kellen Foundation Total Knee Improvement Program.

Disclosure of Interests

Bella Mehta Paid instructor for: Novartis, Susan Goodman Consultant of: UCB, Grant/research support from: Novartis, Edward DiCarlo: None declared, Deanna Jannat-Khah Shareholder of: AstraZeneca, Cytodyn, and Walgreens, J. Alex Gibbons: None declared, Miguel Otero Consultant of: Regeneron Pharmaceuticals, Grant/research support from: Tissue Genesis, Laura Donlin Speakers bureau: Stryker, Consultant of: Stryker, Grant/research support from: Karius, Inc, Tania Pannellini: None declared, William Robinson: None declared, Peter Sculco Consultant of: Intellijoint Surgical, DePuy Synthes, Lima Corporate, Zimmer Biomet, and EOS Imaging, Grant/research support from: Intellijoint Surgical and Zimmer Biomet, Mark Figgie Shareholder of: HS2, Mekanika, and Wishbone, Consultant of: Lima and Wishbone, Jose Rodriguez Consultant of: ConforMIS, Medacta, Exactech, Inc, and Smith & Nephew, Grant/research support from: DePuy, Exactech, Inc, and Smith & Nephew, Jessica Kirschmann: None declared, James Thompson: None declared, David Slater: None declared, Damon Frezza: None declared, Zhenxing Xu: None declared, Fei Wang: None declared, Dana Orange: None declared

Multianalyte assay system developed for drugs of abuse

A simple, 10-min immunoassay system has been developed that simultaneously screens for five different classes of drugs of abuse in a urine sample. This system tests for amphetamines, cannabinoids, cocaine metabolites, opiates, and phencyclidine, and each assay has a specific preset cutoff concentration. Accuracy is &gt; 99% for reporting positive or negative results for samples with 200% or 50%, respectively, of the cutoff concentrations of the drugs. Tests of a panel of 96 compounds yielded only three cases of nonspecific reactivity (at a drug concentration of 100 mg/L). Another panel of 12 compounds that could normally be found in urine samples was also evaluated and no interferences were observed. Concordance was &gt; 95% between this system and the comparable automated immunoassays for detecting drugs of abuse. Greater than 98% of GC/MS-confirmed positive samples gave positive results with this assay system.

A retrospective 3-year study of salivary gland FNAC with categorisation using the Milan reporting system

INTRODUCTION

To assess our practice using the recently developed standardised classification system designated The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) and to ascertain the rates of malignancy for each category by means of a retrospective study.

METHODS

All salivary gland FNAC samples received between 1 January 2013 and 31 December 2015 were retrospectively assigned a diagnostic category code from the MSRSGC. Cytology results were correlated with subsequent histology (where available), and clinical and radiological follow up.

RESULTS

A total of 287 salivary gland FNA samples were received from 272 patients. The specimens were classified as non-diagnostic (21.3%), non-neoplastic (22%), atypia of undetermined significance (2.4%), neoplasm benign (36.9%), neoplasm of uncertain malignant potential (5.2%), suspicious for malignancy (1.7%) and malignant (10.5%; low grade 1.4% and high grade 9.1%). Histological and clinical/radiological follow up was available for 138 (48.1%) specimens, clinical/radiological follow up only for 145 (50.5%) and no follow up for the remaining four (1.4%) samples. The risk of malignancy for each category was non-diagnostic (8.5%), non-neoplastic (1.6%), atypia of undetermined significance (0%), neoplasm benign (1.9%), neoplasm of uncertain malignant potential (26.7%), suspicious for malignancy (100%) and malignant (100%).

CONCLUSIONS

The MSRSGC appears to be a useful tool to guide clinical management and provide an indication of possible risk of malignancy. We favour implementing use of these categories in our reporting practice with a future re-evaluation to assess maintenance of service quality as well as the clinical utility of this reporting system.

Coagulation Abnormalities in Fatal Cerebral Lupus Erythematosus1

Two cases of fatal systemic lupus erythematosus (SLE) with cerebral involvement are described. Both showed widespread microinfarction of the brain secondary to platelet and fibrin thrombi. There was no evidence of vasculitis. Anticoagulants and antiplatelet drugs may have an important role in the management of cerebral SLE.

Clinicopathological Studies of Gastrointestinal Disease in Macaques

Evaluation of mortality during a two-year period at a primate colony indicated that 34% of nonexperimental deaths in macaques one year of age and older were due to gastrointestinal disease. Of deaths related to gastrointestinal disease, 12% had acute gastric dilatation, 18% had shigellosis, 12% had nontuberculous mycobacterial disease, and 58% were of undetermined cause. Histologic evaluation of the alimentary tract indicated that the large intestine was the most common site of anatomical change in monkeys that had diarrhea at the time of death. Monkeys that had a single terminal episode of diarrhea had less gastric inflammatory lesions than those that had multiple episodes of diarrhea in the last year of life.

Pressure Vessels of High Proof Strength Warm Worked Stainless Steel

In order to establish the necessary data to enable high proof strength austenitic stainless steels to be used for the fabrication of pressure vessels, plates were produced with an increased proof stress obtained by the warm working method. The laboratory investigation then showed that it was practicable to raise the proof strength of this material to twice the normal value for fully softened plate with an improvement in the ultimate tensile strength.

Following this, two similar experimental vessels were manufactured in normal and high proof strength 18% Cr-8% Ni-Ti stabilized steel and these were subjected to hydraulic pressure testing. The vessel tests showed how stainless steel vessels behave under static pressure application at room temperature, and the behaviour of the high proof strength vessel indicated that it would be quite safe at nearly double the design pressure for the fully softened vessel. The strain hardening of stainless steel, fabricating techniques and weld quality have also been investigated and these are reported upon in the paper. Proposals for design stress criteria and stress values are made in relation to an examination of existing pressure vessel codes and the experimental data.

A preliminary evaluation of pre-treatment hypodontia patients using the Dental Aesthetic Index: how does it compare with other commonly used indices?

There is currently no specific occlusal index related to hypodontia and there is a paucity of published literature on this subject. The aim of this study was to determine the relationship, if any, between the Peer Assessment Rating (PAR) Index, the Index of Complexity, Outcome and Need (ICON), and the Dental Aesthetic Index (DAI) score and the severity of hypodontia. All new patients attending the Newcastle Dental Hospital hypodontia clinic between February 2002 and March 2003 were included in the study. Of the 60 patients, two were excluded as the models were unavailable and one because they were predominantly in the primary dentition, making scoring impractical. The patient casts were scored with respect to PAR, ICON, and DAI. The mean patient age at presentation was 12 years, with a standard deviation of 1.89 and a range of 9-16 years, and a female to male ratio of 1.1:1. A significant positive correlation, using Kendall tau b, was found between the number of missing teeth, excluding third molars, and the DAI score (tau = 0.215, P = 0.027). There was no significant positive correlation between PAR (tau = -0.186, P = 0.056) and ICON (tau = 0.017, P = 0.861) score and the number of missing teeth. The results of this investigation indicate that further research is required in order to assess if the DAI could be used to determine whether or not to refer hypodontia patients for specialist advice.

An alloantibody to a high-prevalence MNS antigen in a person with a GP.JL/Mk phenotype

The low-prevalence MNS blood group antigenTSEN is located at the junction of glycophorin A (GPA) to glycophorin B (GPB) in several hybrid glycophorin molecules. Extremely rare people have RBCs with a double dose of the TSEN antigen and have made an antibody to a high-prevalence MNS antigen. We report the first patient who is heterozygous for GYP.JL and Mk. During prenatal tests,an alloantibody to a high-prevalence antigen was detected in the serum of a 21-year-old Hispanic woman. The antibody detected an antigen resistant to treatment by papain, trypsin, alpha-chymotrypsin, or DTT. The antibody was strongly reactive by the IAT with all RBCs tested except those having the MkMk, GP.Hil/GP.Hil, or GP.JL/GP.JL phenotypes. The patient's RBCs typed M+N-S+/-s-U+, En(a+/-), Hut-, Mi(a-), Mur-, Vw-, Wr(a-b-), and were TSEN+, MINY+. Reactivity with Glycine soja suggested that her RBCs had a decreased level of sialic acid. Immunoblotting showed the presence of monomer and dimer forms of a GP(A-B) hybrid and an absence of GPA and GPB. Sequencing of DNA and PCR-RFLP using the restriction enzyme RsaI confirmed the presence of a hybrid GYP(AB). The patient's antibody was determined to be anti-EnaFR. She is the first person reported with the GP.JL phenotype associated with a deletion of GYPA and GYPB in trans to GYP.JL.

Primary B-cell lymphoma of the skin: the Sheffield Lymphoma Group Experience (1984-2003)

The clinical presentation, treatment and outcome were retrospectively evaluated in a series of 66 patients with primary B-cell lymphoma of the skin, referred to the Sheffield lymphoma group (SLG) between 1984 and 2003. This is the largest series reported from the UK. The lymphoma database was searched and clinical records were reviewed. Absence of any detectable extracutaneous lesion and the expression of B-cell restricted antigens by neoplastic cells were the essential criteria for selection of cases. The cohort included 37 (56%) males and 29 (44%) females with a mean age of 59 years. The most commonly involved site was the trunk and the disorder typically showed non-aggressive clinical behaviour; the majority of the patients presented with stage I (82%) disease with a tendency to remain localised to a limited area of the skin. Follicular lymphoma was the most common histologic subtype (35%), the next most frequent was the diffuse large cell lymphoma (32%) whereas marginal zone lymphoma constituted 15%. The majority (47%) of patients were treated with radiotherapy for localised disease whereas chemotherapy was given in 20% of patients, with single agent chlorambucil being most frequently used. Surgical excision as the sole modality of treatment was adequate in 33%. Disease-free survival (DFS) was 91% at 1 year, 82% at 2 years and 60% at 5 years. DFS was significantly lower with older age (>45 years), leg lesions, generalised and multiple lesions, and for those treated with chemotherapy. The survival at 5 and 10 years was 80%. The histologic grade, leg involvement and the number of lesions were the most significant variables affecting overall survival. Only 7 patients died of lymphoma. In conclusion, primary cutaneous B-cell lymphoma represents a specific entity concerning clinical behaviour, response to treatment, and overall prognosis.

Expression of cyclooxygenase enzymes in rat hypothalamo-pituitary-adrenal axis: effects of endotoxin and glucocorticoids

Prostaglandins play a key role in mediating the hypothalamo-pituitary-adrenocortical (HPA) responses to immune insults. This study aimed to provide some insight into the relative contributions of the constitutive and inducible forms of cyclooxygenase (COX-1 and COX-2) to the generation of these prostanoids by examining the effects of (1) endotoxin treatment on the expression of COX-1 and COX-2 mRNAs in the various components of the HPA axis in control and glucocorticoid pretreated rats, and (2) selective inhibition of COX-2 on the production of corticosterone by adrenal tissue in vitro. Endotoxin caused a marked rise in COX-2 mRNA in the adrenal gland that was evident 3 and 6 h after the injection and was prevented by pretreatment with dexamethasone. It also induced a modest increase in COX-2 mRNA in the hypothalamus but not in the hippocampus or anterior pituitary gland. By contrast, COX-1 mRNA was largely unaffected by the drug treatments in all tissues studied. In vitro the selective COX-2 inhibitor SC-236 caused a marked reduction in adrenocorticotropic hormone-driven corticosterone release, as did the nonselective COX inhibitor, indomethacin. These results support a role of COX-2 in the manifestation of the HPA responses to endotoxin, particularly within the adrenal gland.

Model acquisition and invariant tracking of unknown materials in hyperspectral images

We consider the problem of acquiring models for unknown materials in airborne 0.4-2.5 microm hyperspectral imagery and using these models to identify the unknown materials in image data obtained under significantly different conditions. The material models are generated with use of an airborne sensor spectrum measured under unknown conditions and a physical model for spectral variability. For computational efficiency, the material models are represented by using low-dimensional spectral subspaces. We demonstrate the effectiveness of the material models by using a set of material tracking experiments in HYDICE images acquired in forest and desert environments over widely varying conditions. We show that techniques based on the new representation significantly outperform methods based on direct spectral matching.

The changing character of regulation: a comparison of Europe and the United States

European and U.S. regulatory policies have changed considerably over the past 30 years. In Europe, since the mid-1980s, consumer and environmental regulation has become more politically salient and regulations have by and large become stricter. On the other hand, in the United States consumer and environmental issues have become less salient and contentious, and regulations have not become (comparatively) stricter. This apparent "flip-flop" of regulatory systems has not been analyzed in much detail to date. This perspective is an attempt to analyze some examples in which it has occurred and identifies one possible cause--namely, credibility.

Oxytocin antagonists: clinical and scientific considerations

Preterm delivery is the largest cause of perinatal mortality and morbidity, yet the treatment of preterm labour has not been demonstrated to improve outcome. The reasons are numerous and complex, but they include a failure to understand the mechanism(s) of preterm labour, the multitude of different causes, the difficulty in diagnosis and the problems of outcome measurement in clinical trials. Recently, an oxytocin antagonist (atosiban) has been introduced into clinical practice in Europe. Although it may be an effective tocolytic, a beneficial effect on perinatal outcome has not been demonstrated. Atosiban has an effect at both oxytocin and vasopressin (V(1a)) receptors, which (assuming efficacy) raises the question as to whether oxytocin or vasopressin V(1a) antagonism is required for tocolysis. This review examines the rationale for tocolysis in preterm labour, the evidence for administration of atosiban and the role for oxytocin, vasopressin and their receptors in the onset of labour. Experimental Physiology (2001) 86.2, 297-302.

Characterization of an antibody to the human melatonin mt1 receptor

Melatonin acts via high affinity, G-protein coupled, seven transmembrane domain receptors. To precisely localize these receptors, antibodies were raised in chickens against a 15 amino acid fragment at the intracellular C-terminal region of the human melatonin receptor subtype mt1 (DSSNDVADRVKWKPS, mt(1338-352)). A chimeric form of the receptor with a hydrophilic Flag peptide (DYKDDDDK) in sequence with the extracellular N-terminus (Flag-mt1) was generated by polymerase chain reaction and expressed in mammalian cell lines. An IgY antibody (Y31), which gave high antibody titres by enzyme-linked immunosorbent assay, was used to localize Flag-mt1 in stably transfected cells by immunofluoresence. Flag-mt1 localization with Y31 was identical to that obtained with the M5 antibody directed against the Flag epitope and was mainly localized to the Golgi apparatus with some staining at the cell surface. No staining was seen in untransfected cells with either antibody. Y31 staining was abolished using antibody preabsorbed with peptide antigen. Y31 immunofluorescence in fetal human kidney sections was restricted to nephrogenic regions and matched that of 2-((125)I)iodomelatonin binding and mt1 gene expression by in situ hybridization. Y31 was used to immunoprecipitate biotinylated membrane proteins from Flag-mt1 stably transfected and untransfected CHO cells. Western blotting of immunoprecipitated proteins revealed two major bands specific to stably transfected cells, one at 63 kDa and one at 86 kDa. The first band almost certainly corresponds to the glycosylated form of Flag-mt1 and the second band to receptor dimers. Thus, Y31 antibody is suitable for use in detecting the human mt1 receptor subtype in tissues and in transfected cells.

Mutant torsinA, responsible for early-onset torsion dystonia, forms membrane inclusions in cultured neural cells

Early-onset torsion dystonia is a hereditary movement disorder thought to be caused by decreased release of dopamine into the basal ganglia, without apparent neuronal degeneration. Recent cloning of the gene responsible for this disease, TOR1A (DYT1), identified the encoded protein, torsinA, as a member of the AAA+ superfamily of chaperone proteins and revealed highest levels of expression in dopaminergic neurons in human brain. Most cases of this disease are caused by a deletion of one glutamic acid residue in the C-terminal region of the protein. Antibodies generated against torsinA revealed expression of a predominant immunoreactive protein species similar to the predicted size of 37.8 kDa in neural, glial and fibroblastic lines by western blot analysis. This protein is N-glycosylated with high mannose content and not, apparently, phosphoryl-ated. Overexpression of torsinA in mouse neural CAD cells followed by immunocytochemistry, revealed a dramatically different pattern of distribution for wild-type and mutant forms of the protein. The wild-type protein was found throughout the cytoplasm and neurites with a high degree of co-localization with the endoplasmic reticulum (ER) marker, protein disulfide isomerase. In contrast, the mutant protein accumulated in multiple, large inclusions in the cytoplasm around the nucleus. These inclusions were composed of membrane whorls, apparently derived from the ER. If disrupted processing of the mutant protein leads to its accumulation in multilayer membranous structures in vivo, these may interfere with membrane trafficking in neurons.

Expression of cyclo-oxygenase types-1 and -2 in human fetal membranes throughout pregnancy

Human labour is associated with increased prostaglandin synthesis within the fetal membranes. We have studied the expression of the two isoforms of the central prostaglandin synthetic enzyme, cyclo-oxygenase (COX-1 and COX-2), in human fetal membranes throughout pregnancy, at mRNA, protein and activity levels. COX-1 mRNA expression was low in human amnion and chorion-decidua and did not change with gestational age. COX-2 mRNA expression in fetal membranes increased with gestational age, with significant up-regulation prior to the onset of labour and in association with labour. Protein concentrations of COX-1 did not change, whilst concentrations of COX-2 increased from the first to the third trimester. COX activity increased with gestational age and in association with labour, although prostaglandin production in fetal membranes collected after labour was reduced, suggesting reduced substrate supply. These data suggest that it is up-regulation of COX-2, rather than of COX-1, which mediates increased prostaglandin synthesis within the fetal membranes at term. Much of the increase in COX-2 expression precedes the onset of labour, suggesting that it is a cause, rather than a consequence, of labour.

Leptin receptor and neuropeptide Y gene expression in the sheep brain

Leptin, a protein secretory product of adipocytes, is important in appetite control, energy balance and reproduction. In rodents, the physiological effects of leptin are centrally mediated, in part via the neuropeptide Y (NPY) system in the hypothalamus. The role of leptin in ruminants, where appropriate nutrition and reproductive status are of major economic concern, is largely unknown. To elucidate the function of leptin in sheep we have investigated putative sites of action for leptin in the brain and pituitary gland using both in-situ hybridization to detect expression of the signalling form of the leptin receptor (OB-Rb) and in-vitro autoradiography using (125I)leptin to detect sites of specific leptin binding. OB-Rb gene expression occurred in the hippocampus, cerebral cortex, preoptic area, stria terminalis and choroid plexus, and within the hypothalamus in the paraventricular (PVN), ventromedial (VHM) and arcuate (ARC) nuclei. OB-Rb gene expression in the ovine pituitary gland was not detected by in-situ hybridization. Sites of OB-Rb and NPY gene expression were compared using both in-situ hybridization on adjacent sections containing the arcuate and ventromedial nuclei, and dual in-situ hybridization on sections containing these areas. In serial sections, OB-Rb expression was found to correspond closely with that of NPY over the arcuate nuclei. Using dual in-situ hybridization, NPY expressing neurones in the arcuate nuclei were also positive for OB-Rb gene expression. Therefore, it appears that leptin may partly act via OB-Rb located on NPY neurones in the sheep hypothalamus as in the rodent.

Efficacy and tolerability of 0.5% timolol maleate ophthalmic gel-forming solution QD compared with 0.5% levobunolol hydrochloride BID in patients with open-angle glaucoma or ocular hypertension

We compared the efficacy of timolol maleate ophthalmic gel-forming solution 0.5% QD with that of levobunolol hydrochloride 0.5% BID, as measured by change in intraocular pressure (IOP), effect on heart rate, and ocular tolerability. The study had a positive-controlled, double-masked, randomized, multicenter, 12-week, two-period (6 weeks each), crossover design. One hundred fifty-two patients with open-angle glaucoma or ocular hypertension were randomized to receive either timolol maleate gel-forming solution QD or levobunolol BID for 6 weeks, followed by a crossover to the alternate treatment. IOP and heart rate were measured at morning trough and peak during weeks 3, 6, 9, and 12. Timolol maleate gel-forming solution QD was comparable to levobunolol BID in reducing IOP at peak and trough. Although the effects on peak heart rate were similar between the two medications, the effect on trough heart rate of timolol maleate gel-forming solution QD was significantly less than that of levobunolol BID (P = 0.001). The incidence of ocular burning and stinging was comparable between the two treatments. Patients experienced significantly more blurred vision when using timolol maleate gel-forming solution than when using levobunolol (P = 0.013). Overall, more patients experienced at least one adverse event when using timolol maleate gel-forming solution. Timolol maleate gel-forming solution QD is as efficacious in reducing IOP as levobunolol BID.

Changes in the expression of the type-2 but not the type-1 cyclo-oxygenase enzyme in chorion-decidua with the onset of labour

OBJECTIVE

To determine the relative expression of cyclo-oxygenase (COX)-1 and COX-2 in the chorion-decidual part of human fetal membranes following delivery at term and to identify any changes in expression associated with labour.

METHODS

Fetal membranes were collected from 12 term pregnancies before labour following elective caesarean section and from 12 spontaneous vaginal deliveries. Expression of COX-1 and COX-2 mRNA was measured using a previously validated quantitative RT-PCR assay.

RESULTS

COX-2 expression exceeded that of COX-1 by approximately eight-fold. COX-1 expression did not change but COX-2 expression was found to increase four-fold with labour.

CONCLUSIONS

Chorion-decidua has the capacity to contribute to the increase in prostaglandin synthesis within the uterus associated with labour. As in the amnion, it is COX-2 and not COX-1 which is upregulated with labour. COX-2 selective anti-prostaglandins should therefore be as effective as nonselective drugs in inhibition of fetal membrane prostaglandin synthesis.

Treatment of advanced pancreatic adenocarcinoma with 5-FU, leucovorin, interferon-alpha-2b, and cisplatin

Previous laboratory and clinical studies support the ability of interferon (IFN) to enhance the antitumor properties of chemotherapy agents, including cisplatin and 5-fluorouracil (5-FU). A phase I-II clinical trial was initiated to treat several tumor types with IFN-alpha-2b, cisplatin, 5-FU, and leucovorin (LV), given daily for 5 days of a 28-day cycle. Because of preliminary results, this was continued as a phase II trial in 18 patients with metastatic adenocarcinoma of the pancreas. Each treatment day consisted of IFN 5 million u/m2 s.c. (maximum, 10 million U), CDDP 20 mg/m2 i.v. over 1 h, LV 20 mg/m2 i.v.p., and 5-FU 250-275 mg/m2 i.v.p. All patients had measurable disease with no prior chemotherapy for metastatic disease, and all had an Eastern Cooperative Oncology Group (ECOG) performance status of 1. Six of the 16 patients evaluable for response had partial responses (PRs) (37.5%) with a median response duration of 4 months, and all responding patients survived > or = 8 months. Median survival of all 18 treated patients was 5 months. Severe gastrointestinal toxicity (nausea, diarrhea, or requirement for i.v. hydration) was common. Grade 4 hematologic toxicity was seen in six patients. The response rate observed is promising and supports the concept that IFN may potentiate the effects of standard chemotherapy agents. However, the toxicities observed with this dosage schedule were considerable and further studies are needed to develop a less toxic regimen.

Computing illumination-invariant descriptors of spatially filtered color image regions

Spatial filters provide a useful and efficient means of analyzing an input color image into components that capture different spatial properties. Representations based on spatial filtering have restricted usefulness for recognition, however, because the output of a spatial filter across an image depends on the scene illumination conditions. We use a physically accurate linear model for spectral reflectance to derive invariants of distributions in spatially filtered color images that do not depend on the scene illumination. These invariants can be used for the illumination-invariant recognition of regions following an arbitrary linear filtering operation. We describe a method for illumination correction based on color distributions and introduce an illumination change consistency constraint that is useful for verifying matches obtained using the invariants. We show, using a set of classification experiments, that the filtered distribution invariants can significantly improve the capability of a recognition system in environments where illumination cannot be controlled.

Sialylation of intestinal microvillar membranes in newborn, sucking and weaned pigs

Affinity cytochemistry and biochemistry revealed distinctive temporal changes in the expression of sialylated and compositionally related membrane glycoconjugates in the pig small intestine between birth and weaning. The expression of membrane NeuAc alpha 2,6 moieties, recognized by Sambucus nigra agglutinin-1, was high in newborn pigs, declined slightly during sucking and was very low in weaned animals. Conversely, the expression of membrane NeuAc alpha 2.3 moieties, recognized by Maackia amurensis agglutinin-2, was low at birth but higher in sucking and weaned animals. Histoblood group O- and A-antigen expression was first detected in a minority of sucking pigs, but was evident in all weaned pigs examined. Lactase glycoforms were isolated from solubilized microvillar membranes of newborn and weaned pigs. The newborn (predominantly alpha 2,6-sialylated) and weaned (predominantly alpha 1,2-fucosylated) glycoforms exhibited similar specific activity, indicating that postnatal lactase decline in the pig intestine is unrelated to temporal changes in membrane sialylation and fucosylation.