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The abdominal cocoon

Yip FW, Lee SH

Aust N Z J Surg, 1992 Aug;62(8):638-42.
PMID: 1642584

Since it was first described in 1978 the abdominal cocoon continues to be a rare cause of intestinal obstruction. So far this rare condition where the small intestine is encased in a fibrous membrane has been reported only in females. Diagnosis is usually made at laparotomy and the treatment of choice is lysis of adhesions. Proper recognition of this benign condition will result in the correct management of it and prevent unnecessary bowel resections. Five new cases including one male patient, together with a review of previous reports in the English literature, are presented.
Fulltext Renal angiomyolipoma--a case report

Yip FW, Lee SH

Singapore Med J, 1992 Dec;33(6):643-4.
PMID: 1488683

Renal angiomyolipoma is a benign tumour of the kidney which is often mistaken for a renal cell carcinoma resulting in an unnecessary nephrectomy. It can be diagnosed preoperatively and managed conservatively without surgery. Large symptomatic renal angiomyolipomas can often be treated by renal-sparing surgery. We report a case of a large renal angiomyolipoma diagnosed preoperatively and excised completely with preservation of the kidney.
Chiral Polymorphic Hydrazine-based Asymmetric Liquid Crystal Trimers with Resorcinol as Linking Group

Goh YP, Yam WS, Yip FW, Hegde G

Curr Org Synth, 2021;18(4):352-365.
PMID: 33530909 DOI: 10.2174/1570179418666210202123935

INTRODUCTION: This is the first report on chiral polymorphic hydrazine-based asymmetric liquid crystal trimers, 1-[4'-(4''-(5-Cholesteryloxy)carbonyl)butyloxy]-3-[N-benzylideneoxy-N'-(4'''-decyloxybenzylidene) hydrazine] butyloxybenzenes, and 1-[4'-(4''-(10-cholesteryloxy)carbonyl)nonyloxy]-3-[N-benzylideneoxy-N'-(4'''- decyloxybenzylidene)hydrazine]butyloxybenzenes., in which the hydrazine and cholesterol arms were connected via two flexible methylene spacers (n = 3-12 units and m = 4 or 9, respectively) to the central resorcinol core.
MATERIALS AND METHODS: FT-IR, 1D and 2D NMR spectroscopy, and CHN microanalysis were used to elucidate the structures of the trimers. Differential scanning calorimetry, polarizing optical microscopy and X-ray diffraction were used to study the transitional and phase properties of the trimers, which were length and spacer parity dependent. Trimers with short spacer length in the cholesteryl arm, m = 4 showed an interesting phase sequence of BP/N*-TGBA*-SmA*.
RESULTS AND DISCUSSION: The TGBA* phase was sensitive to spacer length as it was only observed in trimers with short ester linkage. For the long analogues, m = 9, characteristic visible reflection and a much simpler phase sequence with only N* and SmA* phases were observed.
CONCLUSION: The X-ray diffraction measurements revealed that layer periodicities of the SmA* phase were approximately half the estimated all-trans molecular length (d/L ≈ 0.44-0.52), thus suggesting that the molecules are either strongly intercalated or bent.
Enantiomeric pairs of ternary copper(ii) complexes and their aldol-type condensation products: synthesis, characterization, and anticancer and epigenetic properties

Lee KY, Ng YL, Wang WS, Ng PY, Chan CW, Lai JW, et al.

Dalton Trans, 2019 Apr 09;48(15):4987-4999.
PMID: 30916098 DOI: 10.1039/c9dt00506d

Chiral enantiomers [Cu(phen)(l-ser)(H2O)]NO31 and [Cu(phen)(d-ser)(H2O)]NO32 (ser = serinato) underwent aldol-type condensation with formaldehyde, with retention of chirality, to yield their respective enantiomeric ternary copper(ii) complexes, viz. l- and d-[Cu(phen)(OCA)(H2O)]NO3·xH2O (3 and 4; phen = 1,10-phenanthroline; OCA = oxazolidine-4-carboxylate; x = 1/2, 0-2) respectively. These chiral complexes were characterized by FTIR, elemental analysis, circular dichroism, UV-visible spectroscopy, fluorescence spectroscopy (FL), molar conductivity measurement, ESI-MS and X-ray crystallography. The crystal structures of 1 and 3 showed both the cationic complexes to have a square pyramidal geometry. These complexes were about nine fold more potent than cisplatin against metastatic MDA-MB-231 breast cancer cells, inducing apoptotic cell death via ROS generation and a massive drop in mitochondrial membrane potential. The results of monitoring EZH1, EZH2 and H3K27me3 revealed that the mode of action of 1-4 also involved the downregulation of EZH2 and it seemed to be independent of the H3K27me3 status.