Phenotypic and Genotypic Characterisation of Inflammatory Bowel Disease Presenting Before the Age of 2 years

OBJECTIVES

Inflammatory bowel disease [IBD] presenting in early childhood is extremely rare. More recently, progress has been made to identify children with monogenic forms of IBD predominantly presenting very early in life. In this study, we describe the heterogeneous phenotypes and genotypes of patients with IBD presenting before the age of 2 years and establish phenotypic features associated with underlying monogenicity.

METHODS

Phenotype data of 62 children with disease onset before the age of 2 years presenting over the past 20 years were reviewed. Children without previously established genetic diagnosis were prospectively recruited for next-generation sequencing.

RESULTS

In all, 62 patients [55% male] were identified. The median disease onset was 3 months of age (interquartile range [IQR]: 1 to 11). Conventional IBD classification only applied to 15 patients with Crohn's disease [CD]-like [24%] and three with ulcerative colitis [UC]-like [5%] phenotype; 44 patients [71%] were diagnosed with otherwise unclassifiable IBD. Patients frequently required parenteral nutrition [40%], extensive immunosuppression [31%], haematopoietic stem-cell transplantation [29%], and abdominal surgery [19%]. In 31% of patients, underlying monogenic diseases were established [EPCAM, IL10, IL10RA, IL10RB, FOXP3, LRBA, SKIV2L, TTC37, TTC7A]. Phenotypic features significantly more prevalent in monogenic IBD were: consanguinity, disease onset before the 6th month of life, stunting, extensive intestinal disease and histological evidence of epithelial abnormalities.

CONCLUSIONS

IBD in children with disease onset before the age of 2 years is frequently unclassifiable into Crohn's disease and ulcerative colitis, particularly treatment resistant, and can be indistinguishable from monogenic diseases with IBD-like phenotype.

Semisynthesis of 3-beta-hydroxyartemisinin

3-beta-Hydroxyartemisinin (5) was synthesized from 3-beta-hydroxydihydroartemisinic acid (7c) via singlet oxygen oxidation followed by air (triplet oxygen) oxidation. Compound 7c was synthesized in two steps from dihydroartemisinic acid, 7a.

Synthesis and antimalarial activity of some 9-substituted artemisinin derivatives

Several 9-substituted derivatives of the antimalarial drug artemisinin have been prepared by functionalizing the double bond of artemisitene and related compounds. Stereochemical assignments for these compounds were made using a combination of NMR experiments, an X-ray diffraction study of one compound, and chemical correlations of several other compounds with this one compound of unambiguous structure and with its epimer. The compounds synthesized show a wide variation in in vitro antimalarial activity.

Peroxides as oxidant antimalarials

To further explore the antimalarial activity of peroxides (e.g. artemisinin 1), twenty-three peroxides (all the compounds shown in Figures 3 and 4) of diverse chemical structure and acceptable stability were selected and tested for antimalarial activity in vitro against Plasmodium falciparum, and in mice against P. berghei. Included were hydroperoxides, dialkyl peroxides, acyl and diacylperoxides, peroxyketals, peroxycarbonates, and endoperoxides. None was active in vivo, although several were reasonably potent in vitro.

Conversion of artemisinin (qinghaosu) to iso-artemisitene and to 9-epi-artemisinin1

The antimalarial agent artemisinin has been converted to two new compounds, ISO-artemisitene and 9- EPI-artemisinin.

2-Acetylpyridine thiosemicarbazones. 12. Derivatives of 3-acetylisoquinoline as potential antimalarial agents

A series of 3-acetylisoquinoline thiosemicarbazones and their related thiosemicarbazides was prepared for evaluation as potential antimalarial agents. The former were synthesized by the reaction of 3-acetylisoquinoline with methyl hydrazinecarbodithioate to give methyl 3-[1-(3-isoquinolinyl)ethylidene]hydrazinecarbodithioate, IV. Displacement of the S-methyl group of this intermediate by the requisite amines gave 3-acetylisoquinoline thiosemicarbazones, V. The corresponding thiosemicarbazides, in which the azomethine bond was reduced, were prepared by the reduction of IV with sodium borohydride to give methyl 3-[1-(3-isoquinolinyl)ethyl]hydrazinecarbodithioate, VI. Reaction of this dithioester with amines gave 1-[1-(3-isoquinolinyl)ethyl-3-thiosemicarbazides, VII. The antimalarial properties of series V and VII were evaluated in mice infected with Plasmodium berghei. Significant curative activity could be observed at doses as low as 40 mg/kg for 3 of 10 compounds in series V and at 160 mg/kg for 3 of 11 compounds in series VII.

Artemisitene, a New Sesquiterpene Lactone Endoperoxide from Artemisia annua

Artemisitene, an endoperoxide closely related to the known antimalarial sesquiterpene artemisinin, has been isolated from ARTEMISIA ANNUA, and its structure has been determined.

Reductive electrochemical HPLC assay for artemisinin (qinghaosu)

Artemisinin ( QINGHAOSU), a sesquiterpene lactone containing a peroxide bridge, is the known antimalarial constituent of the herb ARTEMISIA ANNUA L. An electrochemical HPLC detection procedure has been developed that provides a sensitive, selective, and rapid assay for artemisinin in crude plant extracts.

Potential prophylactic antitumor activity of retinylidene 1,3-diketones

Treatment of all-trans-retinal with a series of 1,3-diketones using Knoevenagel conditions gave the expected condensation products. These retinylidene 1,3-diketones were characterized and their biological activities in the hamster tracheal organ culture test measured. It was found that the cyclohexane- 1,3-dione derivatives are highly active in this in vitro assay, while other 1,3-diketones are less active. Retinylidenedimedone has been chosen for further evaluation.