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S J Horton

Publications and source records attributed to S J Horton.

9 recordsLinked to original sources
PubMed2006

Recurring enteric peritonitis associated with non-perforating colon carcinoma.

Peritonitis of enteric origin may occur during treatment with peritoneal dialysis due to visceral perforation or injury or, in the absence of perforation, due to transmural migration of enteric bacteria across the bowel wall into the peritoneal cavity. To the best of our knowledge, peritonitis has not previously been reported associated with carcinomatous colon polyp in the absence of bowel wall perforation. We describe the case of a 31-year-old female who experienced recurring episodes of enteric peritonitis associated with a clinically occult adenocarcinoma of the colon, without having any other known risk factors for peritonitis. A 15 mm carcinomatous polyp was not visible on CT scan but was found at colonoscopy with polypectomy. She proceeded to transverse colectomy; the resected colon showed no evidence of bowel wall perforation. This case demonstrates that a non-perforating carcinomatous polyp of the colon may predispose to enteric peritonitis in the setting of peritoneal dialysis, and it emphasizes the importance of making an aggressive search for underlying pathology, in patients who present with recurring enteric peritonitis or unusual presentations of enteric peritonitis.

Adenocarcinoma↗
PubMed2004

Exploring the idiotypes of insulin antibodies as markers for remission in Type 1 diabetes.

AIMS: Complete or partial remission can occur in newly diagnosed Type 1 diabetes patients. We created idiotype-specific reagents to explore the idiotypes of insulin antibodies (IA) in a patient in remission, and to compare with a patient who was not. METHODS: Phage display was used to create a library of phagotopes specific to insulin binding in four sera. Sera from a Type 1 diabetes subject deemed to have undergone remission were taken at diagnosis and again during remission. Sera from a non-remitter were taken at diagnosis and after 3 months on insulin. Phagotopes from the four sera were randomly selected and tested for insulin specificity in a radiobinding assay by using sera from remitters and non-remitters. RESULTS: IA-binding phagotope selected from serum during remission displaced insulin binding in all nine IA(+) remitters and all 10 IA(+) non-remitters. IA-binding phagotope selected from the non-remission patient (3 months after insulin therapy) displaced insulin binding in 8/9 IA(+) remitters and 8/10 IA(+) non-remitters. The consensus peptide sequences adduced from the phages were identical for both these phagotopes. Phagotopes derived from insulin autoantibody-positive individuals at diagnosis were unable to displace insulin binding in the IA(+) sera 3 months later, whether in remission or not. CONCLUSIONS: We have established the principle of using phage display in the investigation of insulin antibodies during remission in Type 1 diabetes. The immunological characteristics of IA 3 months after the introduction of insulin treatment were different from those at diagnosis of Type 1 diabetes (IAA). Using phage display technology, it was not possible to distinguish insulin antibodies according to remission status.

Adolescent↗
PubMed2003

The use of phage display to distinguish insulin autoantibody (IAA) from insulin antibody (IA) idiotypes.

AIM/HYPOTHESIS: Radiobinding assays (RBA) are unable to differentiate insulin autoantibodies (IAA) from insulin antibodies (IA). We sought to establish whether random peptide phage display might generate reagents with which to distinguish IAA idiotopes from IA idiotopes. METHODS: Two insulin-binding sera were used to select phagotopes from a phage library. The first, designated IAS, came from an insulin-treated patient with the insulin autoimmune syndrome, and was known to contain both IA and a high titre of human insulin specific (B30 threonine dependent) IAA. The second, designated IDD, was taken from a newly-diagnosed IAA(+) Type 1 diabetic patient. Phage colonies selected by insulin-purified IgG extracts of IAS and IDD were selected at random for DNA sequencing, and tested for their reactivity with insulin antibodies and ability to distinguish disease-associated idiotopes. RESULTS: Seven phagotopes bound IAS and the phagotope designated IAS-9, corresponding to sequence KRSRLDV, gave the highest binding standard deviation (SD) score. Seven phagotopes bound IDD and the phagotope designated IDD-10, corresponding to sequence LGRGGSK, bound most strongly. IAS-9 was able to displace insulin binding in IAS and all of ten insulin-treated Type 2 diabetic patients, but not the IAA present in any of the eight patients with newly-diagnosed Type 1 diabetes. IDD-10, on the other hand, could displace insulin binding detected in the sera of eight patients with untreated Type 1 diabetes (IAA), but not in IAS or sera of the insulin-treated Type 2 diabetics. CONCLUSION: Phagotopes provide reagents which between them can distinguish positively as well as negatively diabetes-associated IAA from non-diabetes associated IAA and from IA.

Amino Acid Sequence↗
PubMed1996

Effects of rhizobium, arbuscular mycorrhizal fungi and anion content of simulated rain on subterranean clover.

An experiment was conducted to determine the extent to which rhizobia, mycorrhizal fungi, and anions in simulated rain affect plant growth response to acid deposition. Germinating subterranean clover seeds were planted in steam-pasteurized soil in pots and inoculated with Rhizobium leguminosarum, Glomus intraradices, Glomus etunicatum, R. leguminosarum + G. intraradices, R. leguminosarum + G. etunicatum, or no microbial symbionts. Beginning 3 weeks later, plants and the soil surface were exposed to simulated rain in a greenhouse on 3 days week(-1) for 12 weeks. Rain solutions were deionized water amended with background ions only (pH 5.0) or also adjusted to pH 3.0 with HNO3 only, H2SO4 only, or a 50/50 mixture of the two acids. Glomus intraradices colonized plant roots poorly, and G. intraradices-inoculated plants responded like nonmycorrhizal plants to rhizobia and rain treatments. Variation in plant biomass attributable to different rain formulations was strongest for G. etunicatum-inoculated plants, and the effect of rain formulation differed with respect to nodulation by rhizobia. The smallest plants at the end of the experiment were noninoculated plants exposed to rains (0.38 g mean dry weight total for 3 plants pot(-1)). Among nonnodulated plants infected by G. etunicatum, those exposed to HNO3 rain were largest, followed by plants exposed to HNO3 + H2SO4, pH 5.0, and H2SO4 rain, in that order. Among plants inoculated with both R. leguminosarum + G. etunicatum, however, the greatest biomass occurred with pH 5.0 rains, resulting in the largest plants in the study (1.00 g/3 plants). Treatment-related variation among root and shoot biomass data reflected those for whole-plant biomass. Based on quantification of biomass and N concentrations in shoot and root tissues, total N content of plants inoculated with G. etunicatum alone and exposed to the HNO3 + H2SO4 rains was approximately the same as plants inoculated with R. leguminosarum + G. entunicatum and exposed to pH 5 rains. Thus, the acid-mixture rains and rhizobia under no acid deposition provided approximately equal amounts of N in biomass. The significant interactions among rain formulation and the symbiotic status of the plants suggest that conclusions concerning the impact of acid deposition on plants in the environment cannot be considered reliable because most experiments on which such assessments are based have not tested confounding influences of microorganisms and precipitation characteristics.

Journal Article↗
PubMed1990

Effects of ozone on three open-pollinated families of Pinus taeda L. grown in two substrates.

Seedlings from three open-pollinated loblolly pine (Pinus taeda L.) families grown in a mixture of commercial peat moss and grade 3 vermiculite (1:3 by volume) or a mixture of mineral soil and peat (1:1 by volume) were exposed to 0, 160 or 320 ppb ozone (O3) for 6h/day, 4 days/week for 8 weeks beginning 12 weeks after transplanting. Before exposures began, seedlings grown in the vermiculite-peat substrate were taller but smaller in diameter than those grown in the mineral soil-peat substrate. After 8 weeks of exposure, seedlings grown in the mineral soil-peat substrate were significantly larger in diameter and total biomass than those grown in the vermiculite-peat substrate. Primary needle and secondary needle injury increased with increasing O3 concentrations. Suppression of diameter growth, shoot weight and root weight was linear as O3 concentration increased. The effect of O3 on height or diameter growth or shoot biomass was not influenced by substrate type; but the suppression of root biomass due to O3 was dependent on substrate, with greater suppression in biomass occurring in the vermiculite-peat substrate. Foliar injury due to O3 was slightly greater in family 8-103, but growth suppression due to O3 was not significantly different among the families. Based on root biomass, response of seedlings to O3 was substrate-dependent.

Journal Article↗
PubMed1985

De novo paracentric inversion in an X chromosome.

A 10 1/2 year old female with skeletal abnormalities was referred for genetic consultation because of learning disabilities and a suggestion of 'Turner-like' stigmata. Cytogenetic analysis revealed a paracentric inversion of an X(q13.1q26.1) chromosome.

Bone and Bones↗