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Post hepatectomy liver failure (PHLF) remains a significant cause of morbidity and mortality after major liver resection. Although the etiology of PHLF is multifactorial, an inadequate functional liver remnant (FLR) is felt to be the most important modifiable predictor of PHLF. Pre-operative evaluation of FLR function and volume is of paramount importance before proceeding with any major liver resection. Patients with inadequate or borderline FLR volume must be considered for volume optimization strategies such as portal vein embolization (PVE), two stage hepatectomy with portal vein ligation (PVL), Yttrium-90 radioembolization, and associating liver partition and portal vein ligation for staged hepatectomy (ALPPS). This paper provides an overview of assessing FLR volume and function, and discusses indications and outcomes of commonly used volume optimization strategies.

Objectives: 3D histology tissue modeling is a useful analytical technique for understanding anatomy and disease at the cellular level. However, the current accuracy of 3D histology technology is largely unknown, and errors, misalignment and missing information are common in 3D tissue reconstruction. We used micro-CT imaging technology to better understand these issues and the relationship between fresh tissue and its 3D histology counterpart. Methods: We imaged formalin-fixed and 2% Lugol-stained mouse brain, human uterus and human lung tissue with micro-CT. We then conducted image analyses on the tissues before and after paraffin embedding using 3D Slicer and ImageJ software to understand how tissue changes between the fixation and embedding steps. Results: We found that all tissue samples decreased in volume by 19.2-61.5% after embedding, that micro-CT imaging can be used to assess the integrity of tissue blocks, and that micro-CT analysis can help to design an optimized tissue-sectioning protocol. Conclusions: Micro-CT reference data help to identify where and to what extent tissue was lost or damaged during slide production, provides valuable anatomical information for reconstructing missing parts of a 3D tissue model, and aids in correcting reconstruction errors when fitting the image information in vivo and ex vivo.

Germ cells contain non-membrane bound cytoplasmic organelles that help maintain germline integrity. In C. elegans they are called P granules; without them, the germline undergoes partial masculinization and aberrant differentiation. One key P-granule component is the Argonaute CSR-1, a small-RNA binding protein that antagonizes accumulation of sperm-specific transcripts in developing oocytes and fine-tunes expression of proteins critical to early embryogenesis. Loss of CSR-1 complex components results in a very specific, enlarged P-granule phenotype. In a forward screen to identify mutants with abnormal P granules, ten alleles were recovered with a csr-1 P-granule phenotype, eight of which contain mutations in known components of the CSR-1 complex (csr-1, ego-1, ekl-1, and drh-3). The remaining two alleles are in a novel gene now called elli-1 (enlarged germline granules). ELLI-1 is first expressed in primordial germ cells during mid-embryogenesis, and continues to be expressed in the adult germline. While ELLI-1 forms cytoplasmic aggregates, they occasionally dock, but do not co-localize with P granules. Instead, the majority of ELLI-1 aggregates accumulate in the shared germline cytoplasm. In elli-1 mutants, several genes that promote RNAi and P-granule accumulation are upregulated, and embryonic lethality, sterility, and RNAi resistance in a hypomorphic drh-3 allele is enhanced, suggesting that ELLI-1 functions with CSR-1 to modulate RNAi activity, P-granule accumulation, and post-transcriptional expression in the germline.

In Caenorhabditis elegans, germline expression programs are actively repressed in somatic tissue by components of the synMuv (synthetic multi-vulva) B chromatin remodeling complex, which include homologs of tumor suppressors Retinoblastoma (Rb/LIN-35) and Malignant Brain Tumor (MBT/LIN-61). However, the full scope of pathways that suppress germline expression in the soma is unknown. To address this, we performed a mutagenesis and screened for somatic expression of GFP-tagged PGL-1, a core P-granule nucleating protein. Eight alleles were isolated from 4000 haploid genomes. Five of these alleles exhibit a synMuv phenotype, whereas the remaining three were identified as hypomorphic alleles of known synMuv B genes, lin-13 and dpl-1. These findings suggest that most suppressors of germline programs in the soma of C. elegans are either required for viability or function through synMuv B chromatin regulation.

Both Mini N and HALN provide similar long term recipient and donor outcomes. Offering techniques such as Mini N and HALN for living donor kidney procurement facilitates the opportunity to provide living donors safer and better tolerated nephrectomy procedures.

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INTRODUCTION: A concomitant diagnosis of Primary Sclerosing Cholangitis (PSC) in patients with Inflammatory Bowel Disease (IBD) is associated with an increased risk of colonic dysplasia. Obesity and hepatic steatosis also have been associated with an increased risk of colonic dysplasia in non-IBD patients. Given the increasing prevalence of obesity in patients with IBD, we aimed to clarify if hepatic steatosis and obesity function as additional risk factors for PSC-associated colonic dysplasia. METHODS: This is a single-center, retrospective cohort study between 1/1/2013 through 12/1/2018. Adult patients with a clinical diagnosis of IBD and PSC that had undergone magnetic resonance cholangiopancreatography (MRCP) were included. Those with an alternative etiology of liver disease (e.g., chronic viral hepatitis, greater than moderate alcohol usage) were excluded. MRCP protocols had been modified to allow liver fat quantification by the MR-proton density fat fraction method. Hepatic steatosis was defined as >5.5% liver fat with obesity defined as body mass index (BMI) >30 kg/m2. Prevalent and incident colonic dysplasia were identified. The co-primary outcomes were the Odds Ratio (OR) for the association between hepatic steatosis or obesity and life-time prevalence of colonic dysplasia. Secondary outcomes included the analogous Hazards Ratio (HR) by a cox-proportional hazards model of colonic-dysplasia free-survival from the time of PSC diagnosis. RESULTS: 112 PSC-IBD patients (80% Ulcerative Colitis, median age at enrollment 48 years, median age at PSC diagnosis 39 years, median BMI 27 kg/m2) had a life-time prevalence of colonic dysplasia in 24 (21%), hepatic steatosis in 22 (20%) and obesity in 23 (21%). Neither hepatic steatosis (OR, 0.8; 95% CI, 0.2-2.6; P = 0.78) nor obesity (OR, 1.1; 95% CI, 0.4–2.9; P = 0.90) were risk factors for the life-time prevalence of colonic dysplasia. Similarly, neither hepatic steatosis (HR, 0.9; 95% CI, 0.3-2.3; P = 0.78) nor obesity (HR, 1.0; 95% CI, 0.9–1.0; P = 0.37), were risk factors for dysplasia-free survival. CONCLUSION: We found that hepatic steatosis and obesity were not associated with increased lifetime prevalence for colonic dysplasia in patients with IBD-PSC. This may imply a different pathway for carcinogenesis in IBD-PSC compared to non-IBD patients.