Transfer of intestinal microbiota from lean donors increases insulin sensitivity in individuals with metabolic syndrome

Alterations in intestinal microbiota are associated with obesity and insulin resistance. We studied the effects of infusing intestinal microbiota from lean donors to male recipients with metabolic syndrome on the recipients' microbiota composition and glucose metabolism. Subjects were assigned randomly to groups that were given small intestinal infusions of allogenic or autologous microbiota. Six weeks after infusion of microbiota from lean donors, insulin sensitivity of recipients increased (median rate of glucose disappearance changed from 26.2 to 45.3 μmol/kg/min; P < .05) along with levels of butyrate-producing intestinal microbiota. Intestinal microbiota might be developed as therapeutic agents to increase insulin sensitivity in humans; www.trialregister.nl; registered at the Dutch Trial Register (NTR1776).     

Selection of probiotic bacteria for prevention of allergic diseases: immunomodulation of neonatal dendritic cells

Modification of intestinal microbiota early in life by administration of probiotic bacteria may be a potential approach to prevent allergic disease. To select probiotic bacteria for in vivo purposes, we investigated the capacity of probiotic bacteria to interact with neonatal dendritic cells (DC) and studied the ensuing T cell polarizing effect. Immature DC were generated from cord blood-derived monocytes and maturation was induced by maturation factors (MF), lipopolysaccharide (LPS) plus MF and Bifidobacterium bifidum, B. infantis, Lactobacillus salivarius, Lactococcus lactis alone or combined with MF. After 12 days of co-culture with DC and Staphylococcus aureus enterotoxin B (SEB) as antigenic stimulus, cytokine production by autologous T cells was determined by intracellular cytokine staining. Additionally, cells were stimulated with CD3 and CD28 monoclonal antibodies and cytokines were measured in supernatants by multiplex assay. The probiotic strains induced partial maturation of DC. Full maturation of DC was induced for all strains tested when MF was added. The percentage of interleukin (IL)-4 producing T cells was lower in T cell cultures stimulated with B. bifidum matured DC compared to MF and LPS matured DC, which coincided with a higher percentage of interferon (IFN)-gamma-producing T cells. Furthermore, T cells stimulated by B. bifidum matured DC produced significantly more IL-10 compared to MF matured DC. Selected species of the Bifidobacterium genus prime in vitro cultured neonatal DC to polarize T cell responses and may therefore be candidates to use in primary prevention of allergic diseases.     

Factors Influencing the Use of Sentinel Lymph Node Biopsy in the Netherlands

Background

In the US, whether a sentinel lymph node biopsy (SLNB) is performed depends on tumor and patient factors, including socioeconomic status (SES) and type of health care insurance. We analyzed which patient and tumor characteristics influenced the use of SLNB in a country where every patient has equal access to healthcare.

Methods

Patients diagnosed with a cutaneous invasive melanoma of ≥1 mm between 2004 and 2011 and living in the northeastern part of the Netherlands were selected from the Netherlands Cancer Registry. Regression analysis was performed to assess the association of patient and tumor characteristics and SLNB use.

Results

SLNB was performed in 42 % of the 2,413 included patients. The frequency of performing SLNB increased between 2004 and 2011 from 24 to 55 % (p < 0.001). Patients were less likely to undergo SLNB if they had a melanoma located in the head and neck area (p < 0.001), when they were over 55 years (p = 0.001), and if they had a low SES (p = 0.03). SLNB use was more likely when the diagnosis of melanoma was made in the university hospital (p = 0.045) or when the Breslow thickness was 2.01–4.0 mm (p = 0.03).

Conclusions

The use of SLNB has increased significantly between 2004 and 2011. However, in 2011 it was still performed in only 55 % of the Dutch patients with a melanoma ≥1 mm. In patients with head and neck melanoma, older patients, and patients with low SES, SLNB was less frequently performed. Patients with T3 melanomas and a diagnosis made in the university hospital more often had an SLNB performed.     

A review of animal models for portal vein embolization

Background

Portal vein embolization (PVE) is a preoperative intervention to increase the future remnant liver (FRL) through regeneration of the non-embolized liver lobes. This review assesses all the relevant animal models of PVE available, to guide researchers who intend to study PVE.

Materials and methods

We performed a systematic literature search in Medline and Pubmed, from 1993–June 2013, using search headings “PVE” and “portal vein ligation”. Articles were included when meeting the selection criteria: experimental animal study on PVE or portal vein ligation and experiments described in 5 animals or more.

Results

Sixty-one articles were selected, describing six different animal models. Most articles reported experiments with rats, rabbits, and pigs. In rats, the increase in wet-weight ratio of the non-occluded liver or total liver weight is greatest in the first 7 d with values ranging from 75%–80.5% on day 7. The volume increase of FRL in the rabbit model is greatest in the first 7 d with values ranging from 33.6%–80% on day 7. In pigs, the largest gain in volume of the FRL was seen in the first 2 wk.

Conclusions

The choice of the model depends on the specific aim of the study. Evaluating the increase in liver volume and liver function after PVE, larger animals as the pig, rabbit, or the dog is useful because of the possibility to apply computed tomography volumetry. To evaluate mechanisms of regeneration after PVE, the rat model is useful, because of the variety of antibodies commercially available.