Chemical basis of microbiome preference in the nematode C. elegans.

Animals are exposed to many microbes in their environment, some of which have been shown to colonize various tissues including the intestine. The composition of the intestinal microbiota affects many aspects of the host's physiology and health. Despite this, very little is known about whether host behavior contributes to the colonization. We approach this question in the nematode C. elegans, which feeds on bacteria and also harbors an intestinal microbiome. We examined the behavior of C. elegans towards CeMbio, a simplified microbiome consisting of twelve strains that represent the bacteria found in the animal's natural environment. We observed that C. elegans raised on E. coli shows a strong preference for three members of CeMbio (Lelliottia amnigena JUb66, Enterobacter hormaechei CEent1, and Pantoea nemavictus BIGb0393) compared to E. coli. Previously, these three bacterial strains have been shown to support faster C. elegans development time than E. coli OP50 and are low colonizers compared to eight other members of CeMbio. We then used gas chromatography coupled to mass spectrometry to identify that these three bacteria release isoamyl alcohol, a previously described C. elegans chemoattractant. We suggest that C. elegans seeks bacteria that release isoamyl alcohol and support faster growth.

Sarcopenia is a strong predictive factor of clinical and oncological outcomes following curative colorectal cancer resection.

BACKGROUND: Skeletal muscle depletion and subsequent functional loss is common in gastrointestinal malignancy. Usual markers of nutritional status may not be part of routine workup. The predictive value of sarcopenia was assessed and compared with clinically utilized factors. The aim of this was to assess the association between computed tomography assessed sarcopenia with outcomes in colorectal cancer resection. METHODS: A total of 228 consecutive patients who underwent curative colorectal cancer resection were included. Skeletal muscle area was measured at L3, with pre-defined gender-specific cut-offs applied to a height standardized index. Albumin, body mass index and Subjective Global Assessment scores were recorded alongside measures of comorbidity. Predictors of complications, mortality, and recurrence were identified through multivariate logistic regression. RESULTS: Computed tomography assessed sarcopenia was significantly associated with longer stays, complications, 30-day mortality, readmissions and recurrence at 1 year. Specific associations with major, respiratory and cardiac complications were seen. It independently predicted overall complications (odds ratio 2.96, confidence interval 1.19-7.35 P = 0.019), recurrence at 1 year (odds ratio 8.00, confidence interval 1.45-44.21, P = 0.017) and an increase in comprehensive complication index of 14 (P = 0.002). Subgroup analysis found sarcopenia predicted overall complications in rectal surgery and major complications in colonic surgery. American Society of Anesthesiologists predicted complications but not major complications while cancer stage also predicted recurrence rates. CONCLUSIONS: Sarcopenia presents an objective, available predictive factor that may be superior to current biochemical and clinical measures of nutritional and functional status. This study found it to be predictive of complication rates and recurrence after curative in colorectal cancer resection.

Contrast-enhanced sonographic appearances of two primary hepatic epithelioid angiomyolipomas.

Epithelioid hepatic angiomyolipoma (Epi-HAML) is a rare hepatic tumor frequently misdiagnosed as hepatocellular carcinoma (HCC). Unlike conventional angiomyolipoma (AML), Epi-HAML contains minimal amount of adipose tissue, which is a radiological distinguishing feature between AML and HCC. Two patients were referred for management of incidentally found hepatic lesions confirmed to be Epi-HAML on post-resection tissue analysis. CT and MRI findings were suggestive of HCC. Contrast-enhanced ultrasound demonstrated intratumoral shunting, a feeding artery, and early draining hepatic vein. These findings should alert radiologists to the possibility of Epi-HAML. Furthermore, these features may be better assessed by contrast-enhanced ultrasound due to its superior dynamic temporal resolution.