Measuring the knot of non-Hermitian degeneracies and non-commuting braids.

Any system of coupled oscillators may be characterized by its spectrum of resonance frequencies (or eigenfrequencies), which can be tuned by varying the system's parameters. The relationship between control parameters and the eigenfrequency spectrum is central to a range of applications. However, fundamental aspects of this relationship remain poorly understood.

Chromosome segregation in Archaea: SegA- and SegB-DNA complex structures provide insights into segrosome assembly.

Genome segregation is a vital process in all organisms. Chromosome partitioning remains obscure in Archaea, the third domain of life. Here, we investigated the SegAB system from Sulfolobus solfataricus.

Attachment and antibiotic response of early-stage biofilms studied using resonant hyperspectral imaging.

Many bacterial species readily develop biofilms that act as a protective matrix against external challenge, e.g., from antimicrobial treatment.

An operon encoding enzymes for synthesis of a putative extracellular carbohydrate attenuates acquired vancomycin resistance in Streptomyces coelicolor.

Actinomycete bacteria use polyprenol phosphate mannose as a lipid-linked sugar donor for extra-cytoplasmic glycosyl transferases that transfer mannose to cell envelope polymers, including glycoproteins and glycolipids. Strains of Streptomyces coelicolor with mutations in the gene ppm1, encoding polyprenol phosphate mannose synthase, and in pmt, encoding a protein O-mannosyltransferase, are resistant to phage ϕC31 and have greatly increased susceptibility to some antibiotics, including vancomycin. In this work, second-site suppressors of the vancomycin susceptibility were isolated.

Disruption of the GDP-mannose synthesis pathway in Streptomyces coelicolor results in antibiotic hyper-susceptible phenotypes.

Actinomycete bacteria use polyprenol phosphate mannose as a lipid linked sugar donor for extra-cytoplasmic glycosyl transferases that transfer mannose to cell envelope polymers, including glycoproteins and glycolipids. We showed recently that strains of Streptomyces coelicolor with mutations in the gene ppm1 encoding polyprenol phosphate mannose synthase were both resistant to phage φC31 and have greatly increased susceptibility to antibiotics that mostly act on cell wall biogenesis. Here we show that mutations in the genes encoding enzymes that act upstream of Ppm1 in the polyprenol phosphate mannose synthesis pathway can also confer phage resistance and antibiotic hyper-susceptibility.

Streptomyces coelicolor strains lacking polyprenol phosphate mannose synthase and protein O-mannosyl transferase are hyper-susceptible to multiple antibiotics.

Polyprenol phosphate mannose (PPM) is a lipid-linked sugar donor used by extra-cytoplasmic glycosyl tranferases in bacteria. PPM is synthesized by polyprenol phosphate mannose synthase, Ppm1, and in most Actinobacteria is used as the sugar donor for protein O-mannosyl transferase, Pmt, in protein glycosylation. Ppm1 and Pmt have homologues in yeasts and humans, where they are required for protein O-mannosylation.

Devosia nitraria sp. nov., a novel species isolated from the roots of Nitraria sibirica in China.

An aerobic, Gram-stain negative, short rod-shaped and motile strain, 36-5-1, was isolated from the roots of Nitraria sibirica in Zhangye city, Gansu province, north-west of China. Phylogenetic analysis based on the 16S rRNA gene sequence and two housekeeping genes (glnA and atpD) indicated that the strain represents a novel species closely related to the Devosia, Rhizobium and Devosia genera with 98.3, 96.

The relationship between somatisation and outcome in patients with severe irritable bowel syndrome.

Objective: This study aimed to assess the relationship between somatisation and outcome in patients with severe irritable bowel syndrome (IBS).

Method: Two hundred fifty-seven patients with severe IBS included in a randomised controlled trial were assessed at baseline and divided into four quartiles on the basis of their somatisation score. The patients were randomised to receive the following over 3 months: brief interpersonal psychotherapy, 20 mg daily of the SSRI antidepressant paroxetine, or treatment as usual.

Nanoscale visualization of a fibrillar array in the cell wall of filamentous cyanobacteria and its implications for gliding motility.

Many filamentous cyanobacteria are motile by gliding, which requires attachment to a surface. There are two main theories to explain the mechanism of gliding. According to the first, the filament is pushed forward by small waves that pass along the cell surface.

Does psychological treatment help only those patients with severe irritable bowel syndrome who also have a concurrent psychiatric disorder?

Objective: We have previously reported improved health-related quality of life in patients with severe irritable bowel syndrome (IBS) following psychological treatments. In this paper, we examine whether this improvement was associated with improvement in psychological symptoms and was confined to those patients who had concurrent psychiatric disorder.

Method: Two hundred and fifty-seven patients with severe IBS entering a psychological treatment trial were interviewed using the Schedules for Clinical Assessment in Neuropsychiatry.

Outcome in severe irritable bowel syndrome with and without accompanying depressive, panic and neurasthenic disorders.

Background: Irritable bowel syndrome often leads to impaired functioning.

Aims: To assess the contribution of psychiatric disorders to impaired outcome in severe irritable bowel syndrome.

Method: Patients with severe irritable bowel syndrome entering a psychological treatment trial (n=257) were interviewed using the Schedules for Clinical Assessment in Neuropsychiatry.

Reported sexual abuse predicts impaired functioning but a good response to psychological treatments in patients with severe irritable bowel syndrome.

Objective: We assessed the effect of reported sexual abuse on symptom severity and health-related quality of life in patients with severe irritable bowel syndrome (IBS) undergoing psychological treatments.

Methods: IBS patients entering a treatment trial who reported prior sexual abuse were compared with the remainder in terms of symptom severity and health-related quality of life (SF-36) at trial entry and 15 months later. Analyses used ANCOVA with age, sex, marital status, and treatment group as covariates.

Changes in tolerance to rectal distension correlate with changes in psychological state in patients with severe irritable bowel syndrome.

Objective: Reduced tolerance to rectal distension has been regarded as a biological marker for irritable bowel syndrome (IBS), but longitudinal studies are few. This study determined whether change in tolerance to rectal distension after psychological treatments was associated with: 1) change in abdominal pain; 2) change in psychological symptoms; 3) a reported history of sexual abuse.

Methods: Participants completed a visual analogue scale of abdominal pain, SCL-90 and Hamilton rating scale of depression; discomfort threshold to rectal distension was determined using a double random staircase protocol.

The cost-effectiveness of psychotherapy and paroxetine for severe irritable bowel syndrome.

Background & Aims: Psychotherapy and antidepressants are effective in patients with severe irritable bowel syndrome (IBS), but the cost-effectiveness of either treatment in routine practice has not been established.

Methods: Patients with severe IBS were randomly allocated to receive 8 sessions of individual psychotherapy, 20 mg daily of the specific serotonin reuptake inhibitor (SSRI) antidepressant, paroxetine, or routine care by a gastroenterologist and general practitioner. Primary outcome measures of abdominal pain, health-related quality of life, and health care costs were determined after 3 months of treatment and 1 year later.