A systemic lupus erythematosus patient with thunderclap headache: reversible cerebral vasoconstriction syndrome

Headaches are common in patients with systemic lupus erythematosus (SLE). It is important to identify the exact cause of headaches in SLE to avoid unnecessary steroid or immunosuppressive therapy like in neuropsychiatric SLE. A 35-year-old woman with SLE suddenly developed severe headache. Magnetic resonance angiography showed multifocal segmental narrowing of cerebral arteries, suggestive of central nervous system vasculitis. However, lack of abnormal enhancement in vessel wall imaging indicated reversible cerebral vasoconstriction syndrome (RCVS) rather than central nervous system vasculitis. The patient was treated with oral nimodipine and she recovered over a period of two months. Following magnetic resonance angiography on day 90 was normal. Herein we report a case of reversible cerebral vasoconstriction syndrome in an SLE patient with literature review.

Regulation of the nisin operons in Lactococcus lactis N8

The antibiotic peptide nisin produced by Lactococcus lactis is used as a food preservative due to its activity against spores and vegetative cells of Gram-positive bacteria. The post-translational maturation of this secreted peptide includes dehydration of serine and threonine residues, lanthionine formation and a proteolytic processing of 23 amino acids from the N-terminus. Mutations in the nisZ, nisB and nisP genes of the biosynthetic nisZBTCIPRK nisin operon were made by gene replacement or integration of a plasmid. The mutations caused a drastic decrease of the transcription from the promoters upstream of the nisZBTCIPRK and nisFEG operons resulting in loss of nisin production and nisin immunity. The transcription of the nisin operons and nisin immunity could be partially restored by adding nisin to the growth medium of the cells. Nisin induction of the mutant strains also increased the level of the putative immunity NisI protein. These results showed that the nisZBTCIPRK operon is positively autoregulated and that the nisFEG operon is in the same regulon.

The codon usage of the nisZ operon in Lactococcus lactis N8 suggests a non-lactococcal origin of the conjugative nisin-sucrose transposon

An 11.6 kb area downstream from the structural gene of nisin Z in the conjugative nisin-sucrose transposon of Lactococcus lactis subsp. lactis N8 was cloned and sequenced. Analysis of the sequence revealed eight open reading frames, nisZBTClPRK, followed by a putative rho-independent terminator (delta G degrees = -4.7 kcal/mol). The C-terminal hydrophilic domain of the NisK protein is homologous to the C-termini of several histidine kinases of bacterial two-component regulator systems, such as SpaK from Bacillus subtilis and KdpD and RcsC of Escherichia coli. The nisin Z biosynthetic genes were highly similar with the genes of the nisin A operons having, however, a 0-3% difference in the amino acid sequences of the individual proteins. The codon usage of eleven genes within the same conjugative transposon was calculated and found to be strikingly different from that of other lactococcal genes. This, together with the low GC-content (32%) compared to the 38% (G+C) of the lactococcal chromosome in general strongly suggests a non-lactococcal origin of this transposon.

Characterization of a birch (Betula pendula Roth.) embryogenic gene, BP8

We have isolated the birch homologue (BP8) for the carrot embryogenic gene DC8 by heterologous hybridization. The birch BP8 gene encodes a putative protein of 53 kDa, showing 52% sequence identity with the DC8 gene at the amino acid level. The putative BP8 protein contains 20 repeats of 11 amino acids and thus belongs to the group of LEA proteins isolated from such plants as carrot, cotton and wheat. Northern hybridization of mRNA isolated from birch cells representing different stages of somatic embryogenesis and non-embryogenetic material with a PB8 probe gave no signals, suggesting a low expression level of the BP8 gene.