Risk of hospitalised bronchiectasis exacerbation based on blood eosinophil counts.

SETTING: There has been growing recognition on the importance of phenotyping of airway diseases. The eosinophilic phenotype was proposed in bronchiectasis; however, there has not been any evidence on its association with the risk of hospitalised bronchiectasis exacerbations.OBJECTIVE: To investigate the association between baseline blood eosinophil count (BEC) and bronchiectasis exacerbations requiring hospitalisation with validation by an independent cohort.DESIGN: This was a retrospective cohort study.RESULTS: Over a 24-month period, 37/318 (11.6%) study participants experienced an exacerbation requiring hospitalisation. The mean baseline serum eosinophil was 135 ± 92 cells/µL in those who had exacerbations, and 188 ± 161 cells/µL in those who did not. A serum eosinophil level of 250 cells/µL at stable state was the most significant cut-off for predicting hospitalised bronchiectasis exacerbation, which was validated by the independent cohort.CONCLUSIONS: Patients with BEC below 250 cells/µL at stable state are at increased risk of having hospitalised bronchiectasis exacerbations.

Herpetic shoulder paresis in a Chinese elderly patient.

A patient with left shoulder girdle weakness secondary to herpetic myotomal paresis is reported. Needle electromyography revealed denervational discharge from the left supraspinatus, deltoid, and brachioradialis muscles, compatible with a radiculopathy that was relevant to his myotomes affected by zoster infection. The patient was managed with range-of-movement and strengthening exercises as well as pain relief for post-herpetic neuralgia. Further studies are required to determine whether antiviral treatment can limit the extent of motor deficit and hasten recovery. Zoster paresis should be one of the differential diagnoses of girdle muscle weakness.

Co-expression of glutathione S-transferase with methionine aminopeptidase: a system of producing enriched N-terminal processed proteins in Escherichia coli.

We describe here an Escherichia coli expression system that produces recombinant proteins enriched in the N-terminal processed form, by using glutathione S-transferase cGSTM1-1 and rGSTT1-1 as models, where c and r refer to chick and rat respectively. Approximately 90% of the cGSTM1-1 or rGSTT1-1 overexpressed in E. coli under the control of a phoA promoter retained the initiator methionine residue that was absent from the mature isoenzymes isolated from tissues. The amount of initiator methionine was decreased to 40% of the expressed cGSTM1-1 when the isoenzyme was co-expressed with an exogenous methionine aminopeptidase gene under the control of a separate phoA promoter. The recombinant proteins expressed were mainly methionine aminopeptidase. The yield of cGSTM1-1 was decreased to 10% of that expressed in the absence of the exogenous methionine aminopeptidase gene. By replacing the phoA with its natural promoter, the expression of methionine aminopeptidase decreased drastically. The yield of the co-expressed cGSTM1-1 was approx. 60% of that in the absence of the exogenous methionine aminopeptidase gene; approx. 65% of the initiator methionine residues were removed from the enzyme. Under similar conditions, N-terminal processing was observed in approx. 70% of the recombinant rGSTT1-1 expressed. By increasing the concentration of phosphate in the growth medium, the amount of initiator methionine on cGSTM1-1 was decreased to 14% of the overexpressed isoenzymes, whereas no further improvement could be observed for rGSTT1-1. The initiator methionine residue does not affect the enzymic activities of either cGSTM1-1 or rGSTT1-1. However, the epoxidase activity and the 4-nitrobenzyl chloride-conjugating activity of the purified recombinant rGSTT1-1 are markedly higher that those reported recently for the same isoenzyme isolated from rat livers.

Amino acid sequence of glutathione S-transferase rGSTM5* from rat testis.

Glutathione S-transferase rGSTM5* was isolated from rat testis with a combination of glutathione affinity column and reverse-phase column chromatography. The protein was digested with Achromobacter protease I or endoproteinase Arg-C. The peptide fragments were isolated for electrospray MS and N-terminal peptide sequencing analyses. The primary amino acid sequence of rGSTM5* comprises 217 residues and has a calculated average molecular mass of 25495.3 Da. The result is identical to that obtained for rGSTM5* with liquid chromatography-MS from a mixture of rat testicular GSTs. Therefore, rGSTM5* has not been post-translationally modified.

10-Epi-olguine from Rabdosia ternifolia.

An unsaturated lactone, 10-epi-olguine (1), has been isolated from Rabdosia ternifolia (D. Don) Hara. The structure was established by spectroscopic and X-ray crystallographic analyses. The compound displayed modest cytotoxicity in several human cancer cell lines.