A double-blind, randomized, placebo-controlled study assessing the impact of probiotic supplementation on the symptoms of irritable bowel syndrome in females

BACKGROUND

A previous exploratory study demonstrated the ability of the Lab4 probiotic to alleviate the symptoms of IBS, and post hoc data analysis indicated greatest improvements in the female subgroup. The aim of this study is to confirm the impact of this multistrain probiotic on IBS symptom severity in females.

METHODS

An 8-week, single-center, randomized, double-blinded, placebo-controlled, superiority study in 70 females with Rome IV-diagnosed irritable bowel syndrome (IBS) receiving the Lab4 probiotic (25 billion colony-forming units) daily or a matched placebo. Changes from baseline in the IBS-symptom severity score (IBS-SSS), daily bowel habits, anxiety, depression, IBS-related control, and avoidance behavior, executive function, and the fecal microbiota composition were assessed. The study was prospectively registered: ISRCTN 14866272 (registration date 20/07/22).

KEY RESULTS

At the end of the study, there were significant between-group reductions in IBS-SSS (-85.0, p < 0.0001), anxiety and depression scores (-1.9, p = 0.0002 and -2.4, p < 0.0001, respectively), and the IBS-related control and avoidance behavior score (-7.5, p = 0.0002), all favoring the probiotic group. A higher proportion of the participants in the probiotic group had normal stool form (p = 0.0106) and/or fewer defecations with loose stool form (p = 0.0311). There was little impact on the overall diversity of the fecal microbiota but there were significant differences in Roseburia, Holdemanella, Blautia, Agathobacter, Ruminococcus, Prevotella, Bacteroides, and Anaerostipes between the probiotic and placebo groups at the end of the study.

CONCLUSIONS & INFERENCES

Daily supplementation with this probiotic may represent an option to be considered in the management of IBS.

Epidermolytic toxin binds to components in the epidermis of a resistant species

Ferritin-labeled epidermolytic toxin selectively bound to resin-impregnated sections of toxin-resistant rat skin. Binding was confined to the keratohyalin granules of the stratum granulosum and to the cytoplasm of cells in the stratum corneum. Single granules, and equivalent regions in composite granules, failed to bind the conjugate. Preferential binding of the ferritin-toxin probe created anastomosed arrays in the large granules. The scoring density within corneal cells varied with the position of the cell in the stratum corneum. It reached a maximum in the fourth cell from the granular-corneal junction, then decreased to a negligible value in the outermost corneal layers. Three groups of toxin-binding polypeptides were identified in epidermal extracts. These include profilaggrin, a group of three histone H1 polypeptides and histone H3. Filaggrin did not react with toxin on Western blots. The findings demonstrate that sensitivity to epidermolytic toxin is not solely dependent on the presence of target material. It is suggested that species-specific differences in the morphology of keratohyalin granules and in metabolism of profilaggrin may be important factors in intoxication.

The binding of epidermolytic toxin from Staphylococcus aureus to mouse epidermal tissue

Fluorescein-labelled epidermolytic toxin (FTC-toxin) of Staphylococcus aureus and ferritin-toxin conjugate have been prepared and purified. FTC-toxin bound selectively to cryostat and resin-impregnated sections of neonatal mouse skin. Binding was localized at the keratohyalin granules and in the stratum corneum. In an epidermal cell (granular, spinous and basal) preparation, only keratohyalin granules of the granular cells bound FTC-toxin. Ferritin-toxin conjugate bound to skin sections at the same two sites as FTC-toxin and was competitive with the binding of free toxin. Keratohyalin granules in unstained sections had a novel 'patched' appearance under the electron microscope, and the ferritin-toxin conjugate bound preferentially to the electron-lucent areas. In the stratum corneum it was shown by quantitative estimation that the target density decreased as the surface of the tissue was approached.

Central venous pressure or pulmonary capillary wedge pressure as the determinant of fluid replacement in aortic surgery

Both central venous pressure (CVP) and pulmonary capillary wedge pressure (PCWP) have been used as guides to fluid replacement in patients undergoing abdominal aortic surgery. To test the hypothesis that changes in PCWP (deltaPCWP) may be reliably estimated from changes in CVP (deltaCVP), 55 patients had simultaneous measurements (302 paired observations) of CVP and PCWP, as well as of cardiac output, before and during operation. The correlation between deltaCVP and deltaPCWP was high (r = 0.716, P less than 0.001). The estimated slope for the linear regression was 0.88. The standard error of the estimate was +/- 3.75 torr, making the prediction of deltaPCWP from deltaCVP accurate only to within 7.5 torr. There were five patients who each had a low and failing CVP accompanied by a stable cardiac output and a rising PCWP; for them, a decision to administer fluid based on the CVP might have resulted in pulmonary edema. Although deltaCVP accurately predicted direction and magnitude of deltaPCWP in the majority of patients (90%), there was a small group in whom there was no substitute for direct measurement of PCWP.

Onset of succinylcholine-induced hyperkalemia following denervation

Denervation injuries in baboons were used to define the time course of the hyperkalemic response to succinylcholine. Half-peak increase in serum potassium (2.78 mEq/l) occurred 8.4 days following injury. Peak increase (5.5 mEq/l) appeared 14 days after injury. However, changes in potassium levels begin as early as four days after injury. Succinylcholine or other depolarizing muscle relaxants should not be used after the fourth day following an injury or denervation that involves two or more limbs.

Fine structure of the host-fungus interface in orchid mycorrhiza

Electron microscopy of protocorms of Dactylorhiza purpurella infected with a symbiotic Rhizoctonia sp. showed that the intracellular hyphae examined did not penetrate the plasmalemma of the host cell. Walls of hyphae within cells bore many hemispherical protuberances over which the host plasmalemma was closely pressed. we estimate that these protuberances would increase the area of contact between hyphae and host plasmalemma by about 15%. They were not found on hyphae growing on agar. Except for these protuberances, and some vesicles or tubules which invaginated the fungus plasmalemma, no other structures were seen which could be suggested to be adaptations to transport across the living fungus-host interface.