Role of tumor size in the pre-operative management of rectal cancer patients

Clinical management of rectal cancer patients relies on pre-operative staging. Studies however continue to report moderate degrees of over/understaging as well as inter-observer variability. The aim of this study was to determine the sensitivity, specificity and accuracy of tumor size for predicting T and N stages in pre-operatively untreated rectal cancers

We're in this Together: Sensation of the Host Cell Environment by Endosymbiotic Bacteria

Bacteria inhabit diverse environments, including the inside of eukaryotic cells. While a bacterial invader may initially act as a parasite or pathogen, a subsequent mutualistic relationship can emerge in which the endosymbiotic bacteria and their host share metabolites. While the environment of the host cell provides improved stability when compared to an extracellular environment, the endosymbiont population must still cope with changing conditions, including variable nutrient concentrations, the host cell cycle, host developmental programs, and host genetic variation. Furthermore, the eukaryotic host can deploy mechanisms actively preventing a bacterial return to a pathogenic state. Many endosymbionts are likely to use two-component systems (TCSs) to sense their surroundings, and expanded genomic studies of endosymbionts should reveal how TCSs may promote bacterial integration with a host cell. We suggest that studying TCS maintenance or loss may be informative about the evolutionary pathway taken toward endosymbiosis, or even toward endosymbiont-to-organelle conversion.Peer reviewe

Colorectal and uterine movement and tension of the inferior hypogastric plexus in cadavers

Background: Hypotheses on somatovisceral dysfunction often assume interference by stretch or compression of the nerve supply to visceral structures. The purpose of this study is to examine the potential of pelvic visceral movement to create tension of the loose connective tissue that contains the fine branches of the inferior hypogastric nerve plexus. Methods: Twenty eight embalmed human cadavers were examined. Pelvic visceral structures were displaced by very gentle 5 N unidirectional tension and the associated movement of the endopelvic fascia containing the inferior hypogastric plexus that this caused was measured. Results: Most movement of the fascia containing the inferior hypogastric plexus was obtained by pulling the rectosigmoid junction or broad ligament of the uterus. The plexus did not cross any vertebral joints and the fascia containing it did not move on pulling the hypogastric nerve. Conclusions: Uterine and rectosigmoid displacement produce most movement of the fascia containing the hypogastric nerve plexus, potentially resulting in nerve tension. In the living this might occur as a consequence of menstruation, pregnancy or constipation. This may be relevant to somatovisceral reflex theories of the effects of manual therapy on visceral conditions.Ian P Johnso

What is the likelihood of colorectal cancer when surgery for ulcerative-colitis-associated dysplasia is deferred?

Surgery aims to prevent cancer-related morbidity for patients with ulcerative colitis (UC)-associated dysplasia. The literature varies widely regarding the likelihood of dysplastic progression to higher grades of dysplasia or cancer. The aim of this study was to characterise the likelihood of the development of colorectal cancer (CRC) of patients with UC-associated dysplasia who chose to defer surgery.A retrospective review was carried out of patients undergoing surgery for UC at the Mayo Clinic, who were diagnosed to have dysplasia between August 1993 and July 2012. The relationships between grade of dysplasia, time to surgery and the detection of unsuspected carcinoma were investigated.175 patients underwent surgery at a median of 4.9 DEAR AUTHOR PLEASE BE HAPPY WITH THIS [IQR:2.5-8.9] months) after a diagnosis of dysplasia. Their median age was 52 (IQR:43-59) years. An initial diagnosis of indeterminate dysplasia was not associated with CRC (0/23; 17.7[8.1-29.6] months). Thirty six patients who had an initial diagnosis of dysplasia progressed from indeterminate to low-grade dysplasia (24.2[11.0-30.4] months). Low-grade dysplasia was associated with a 2% (1/56; T2N0M0) risk of CRC when present in random surveillance biopsies and a 3% (2/61; T1N0M0, T4N0M0) risk if detected in endoscopically visible lesions (7.4[5.2-33.3] months). Eighteen patients progressed from indeterminate to high-grade dysplasia (19.1 [9.2-133.9] months). Seventeen patients progressed from low- to high-grade dysplasia (11.0[5.8-30.1] months). None of the patients with high-grade dysplasia (0/35) progressed to CRC (4.5[1.7-9.9] months).Dysplasia was associated with a low incidence of node negative CRC if surgery was deferred for up to five years. These findings may help inform the decision-making process for asymptomatic patients who are having to decide between intensive surveillance or surgery for UC associated-dysplasia. This article is protected by copyright. All rights reserved

TREM-1 deficiency can attenuate disease severity without affecting pathogen clearance.

Triggering receptor expressed on myeloid cells-1 (TREM-1) is a potent amplifier of pro-inflammatory innate immune reactions. While TREM-1-amplified responses likely aid an improved detection and elimination of pathogens, excessive production of cytokines and oxygen radicals can also severely harm the host. Studies addressing the pathogenic role of TREM-1 during endotoxin-induced shock or microbial sepsis have so far mostly relied on the administration of TREM-1 fusion proteins or peptides representing part of the extracellular domain of TREM-1. However, binding of these agents to the yet unidentified TREM-1 ligand could also impact signaling through alternative receptors. More importantly, controversial results have been obtained regarding the requirement of TREM-1 for microbial control. To unambiguously investigate the role of TREM-1 in homeostasis and disease, we have generated mice deficient in Trem1. Trem1(-/-) mice are viable, fertile and show no altered hematopoietic compartment. In CD4(+) T cell- and dextran sodium sulfate-induced models of colitis, Trem1(-/-) mice displayed significantly attenuated disease that was associated with reduced inflammatory infiltrates and diminished expression of pro-inflammatory cytokines. Trem1(-/-) mice also exhibited reduced neutrophilic infiltration and decreased lesion size upon infection with Leishmania major. Furthermore, reduced morbidity was observed for influenza virus-infected Trem1(-/-) mice. Importantly, while immune-associated pathologies were significantly reduced, Trem1(-/-) mice were equally capable of controlling infections with L. major, influenza virus, but also Legionella pneumophila as Trem1(+/+) controls. Our results not only demonstrate an unanticipated pathogenic impact of TREM-1 during a viral and parasitic infection, but also indicate that therapeutic blocking of TREM-1 in distinct inflammatory disorders holds considerable promise by blunting excessive inflammation while preserving the capacity for microbial control