Background: Human intestinal epithelial cells (IECs) secrete the chemokine CCL20 in response to infection by various enteropathogenic bacteria or exposure to bacterial flagellin. CCL20 recruits immature dendritic cells and lymphocytes to target sites. Here we investigated IEC responses to various pathogenic and commensal bacteria as well as the modulatory effects of commensal bacteria on pathogen-induced CCL20 secretion. HT-29 human IECs were incubated with commensal bacteria (Bifidobacterium infantis or Lactobacillus salivarius), or with Salmonella typhimurium, its flagellin, Clostridium difficile, Mycobacterium paratuberculosis, or Mycobacterium smegmatis for varying times. In some studies, HT-29 cells were pre-treated with a commensal strain for 2 hr prior to infection or flagellin stimulation. CCL20 and interleukin (IL)-8 secretion and nuclear factor (NF)-κB activation were measured using enzyme-linked immunosorbent assays.

A multidisciplinary management approach to fragility fracture of the femoral neck that involves comprehensive geriatric assessment, daily medical involvement of a geriatric team and specialised follow-up assessment leads to a significant reduction in mortality and improved outcomes.

This study highlights specific patient comorbidities and medical complications that could be used to guide clinical assessment, management and targeted interventions that improve outcomes in this patient group.

Orthostatic hypotension (OH) and vitamin B12 deficiency are common disorders in older people. Several case series have reported an association between vitamin B12 deficiency and OH. The effect of vitamin B12 replacement on this dysfunction has not been studied. We prospectively studied responses to head up tilt in patients over 70 years with vitamin B12 deficiency (intervention group) and compared their responses after replacement to those of matched patients with idiopathic OH and normal serum vitamin B12 concentrations (control group). Blood pressure (BP), heart rate (HR) and systemic vascular resistance (SVR) changes during orthostatic stress were evaluated using digital artery photoplethysmography. Eight patients and eight controls were studied. Initial head up tilt produced a mean BP decrease of 44/29 mmHg (s.e.m. 4/4 mmHg) in the intervention group and 33/12 mmHg (s.e.m. 3/2 mmHg) in the control group. Repeat head up tilt 6 months after vitamin B12 replacement produced a mean BP decrease of 15/9 mmHg (s.e.m. 5/2 mmHg) in the intervention group. The mean decrease in the control group was 30/12 mmHg (s.e.m. 2/2 mmHg). The difference in BP decreases between groups was statistically significant for both systolic and diastolic BP (p < 0.001 for both systolic BP and diastolic BP). Mean SVR in the intervention group decreased by 658 dynes/cm5/sec (s.e.m. 74 dynes/cm5/sec) during initial head up tilt. Mean SVR during repeat head up tilt decreased by 79 dynes/cm5/sec (s. e. m. 12 dynes/cm5/sec). Mean SVR in the control group decreased by 158 dynes/cm5/sec (s. e. m. 10 dynes/cm5/sec) during initial head up tilt and by 258 dynes/cm5/sec (s. e. m. 31 dynes/cm5/sec). The difference in SVR changes between groups was statistically significant (p = 0.02). We conclude that replacing vitamin B12 in older patients with vitamin B12 deficiency is associated with improved orthostatic tolerance to head up tilt.