A Technique to Address Peritoneal Dialysis Catheter Malfunction

Malpositioned peritoneal dialysis catheters may be repositioned laparoscopically with a testicular prosthesis used as an anchoring weight

Pancreatic Fistula Following Pancreaticoduodenectomy: Clinical Predictors and Patient Outcomes

Pancreatic fistula continues to be a common complication following PD. This study seeks to identify clinical factors which may predict pancreatic fistula (PF) and evaluate the effect of PF on outcomes following pancreaticoduodenectomy (PD). We performed a retrospective analysis of a clinical database at an academic tertiary care hospital with a high volume of pancreatic surgery. Five hundred ten consecutive patients underwent PD, and PF occurred in 46 patients (9%). Perioperative mortality of patients with PF was 0%. Forty-five of 46 PF (98%) closed without reoperation with a mean time to closure of 34 days. Patients who developed PF showed a higher incidence of wound infection, intra-abdominal abscess, need for reoperation, and hospital length of stay. Multivariate analysis demonstrated an invaginated pancreatic anastomosis and closed suction intraperitoneal drainage were associated with PF whereas a diagnosis of chronic pancreatitis and endoscopic stenting conferred protection. Development of PF following PD in this series was predicted by gender, preoperative stenting, pancreatic anastomotic technique, and pancreas pathology. Outcomes in patients with PF are remarkable for a higher rate of septic complications, longer hospital stays, but in this study, no increased mortality

USF-1 Is Critical for Maintaining Genome Integrity in Response to UV-Induced DNA Photolesions

An important function of all organisms is to ensure that their genetic material remains intact and unaltered through generations. This is an extremely challenging task since the cell's DNA is constantly under assault by endogenous and environmental agents. To protect against this, cells have evolved effective mechanisms to recognize DNA damage, signal its presence, and mediate its repair. While these responses are expected to be highly regulated because they are critical to avoid human diseases, very little is known about the regulation of the expression of genes involved in mediating their effects. The Nucleotide Excision Repair (NER) is the major DNA–repair process involved in the recognition and removal of UV-mediated DNA damage. Here we use a combination of in vitro and in vivo assays with an intermittent UV-irradiation protocol to investigate the regulation of key players in the DNA–damage recognition step of NER sub-pathways (TCR and GGR). We show an up-regulation in gene expression of CSA and HR23A, which are involved in TCR and GGR, respectively. Importantly, we show that this occurs through a p53 independent mechanism and that it is coordinated by the stress-responsive transcription factor USF-1. Furthermore, using a mouse model we show that the loss of USF-1 compromises DNA repair, which suggests that USF-1 plays an important role in maintaining genomic stability

T-cell Receptor (TCR)-Peptide Specificity Overrides Affinity-enhancing TCR-Major Histocompatibility Complex Interactions

αβ T-cell receptors (TCRs) engage antigens using complementarity-determining region (CDR) loops that are either germ line-encoded (CDR1 and CDR2) or somatically rearranged (CDR3). TCR ligands compose a presentation platform (major histocompatibility complex (MHC)) and a variable antigenic component consisting of a short “foreign” peptide. The sequence of events when the TCR engages its peptide-MHC (pMHC) ligand remains unclear. Some studies suggest that the germ line elements of the TCR engage the MHC prior to peptide scanning, but this order of binding is difficult to reconcile with some TCR-pMHC structures. Here, we used TCRs that exhibited enhanced pMHC binding as a result of mutations in either CDR2 and/or CDR3 loops, that bound to the MHC or peptide, respectively, to dissect the roles of these loops in stabilizing TCR-pMHC interactions. Our data show that TCR-peptide interactions play a strongly dominant energetic role providing a binding mode that is both temporally and energetically complementary with a system requiring positive selection by self-pMHC in the thymus and rapid recognition of non-self-pMHC in the periphery

Use of Diagnostic Laparoscopy in a Patient with Gastric Pneumatosis and Portal Venous Gas

Gastric pneumatosis is a radiographic finding that represents a spectrum of conditions ranging from benign disease to abdominal sepsis and death. Along with portal venous gas, it is generally considered an ominous sign prompting emergent operative intervention. We report a rare case showing that diagnostic laparoscopy can be used to confirm or refute full thickness ischemic necrosis and that conservative management can be considered in some patients, recognizing the possibility of a benign process

High-precision isotopic analysis of serum and whole blood Cu, Fe and Zn to assess possible homeostasis alterations due to bariatric surgery

Bariatric surgery is an effective procedure to achieve weight loss in obese patients. However, homeostasis of essential metals may be disrupted as the main absorption site is bypassed. In this study, we determined Cu, Fe and Zn isotopic compositions in paired serum and whole blood samples of patients who underwent Roux-en-Y gastric bypass (RYGB) surgery for evaluation of longitudinal changes and their potential relation to mineral element concentrations and relevant clinical parameters used for monitoring the patient's condition. Samples from eight patients were collected pre-surgery and at 3, 6 and 12 months post-surgery. Multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS) was used for high-precision isotope ratio measurements. Alterations in metal homeostasis related to bariatric surgery were reflected in the serum and whole blood Cu, Fe and Zn isotopic compositions. The serum and whole blood Cu became isotopically lighter (lower delta Cu-65 values) after bariatric surgery, reaching statistical significance at 6 months post-surgery (p < 0.05). The difference between the serum and the whole blood Zn isotopic composition increased after surgery, reaching significance from 6 months post-surgery onwards (p < 0.05). Those changes in Cu, Fe and Zn isotopic compositions were not accompanied by similar changes in their respective concentrations, making isotopic analysis more sensitive to physiological changes than elemental content. Furthermore, the Zn isotopic composition correlates with blood glycaemic and lipid parameters, while the Fe isotopic composition correlates with glycaemic parameters

A Pilot Study of Perillyl Alcohol in Pancreatic Cancer

Background Chemotherapy has been largely unsuccessful in pancreatic cancer. Measurement of cell-specific biological endpoints may clarify the evaluation of a newer generation of compounds. Perillyl alcohol has shown chemotherapeutic activity in preclinical systems through enhancing apoptosis. Aims To pilot a new trial template for testing novel agents in pancreatic cancer and to assess the biological activity of perillyl alcohol in patients with resectable pancreatic cancer. Methods Apoptosis was quantified with ApopTag in situ, Bak staining, and light microscopy. Tumor size, serum CA 19–9 level, and survival were also measured. Results Eight patients enrolled. Toxicity was mild and perillyl alcohol was generally well tolerated. Tumor size and CA 19–9 level were unchanged with perillyl alcohol treatment. Survival time was longer in patients who received full perillyl alcohol treatment (288 ± 32 days) compared to those who did not (204 ± 96 days), but this result did not achieve statistical significance (P = 0.2). There was a trend toward greater apoptosis in patients receiving perillyl alcohol compared to fresh operative controls; there was also a suggestion of greater apoptosis in tumor compared to normal pancreatic tissue in the same patient. Conclusions Incorporation of cell-specific biological endpoints is challenging but feasible and should be used in clinical studies of pancreatic cancer treatment. Our pilot study suggests that perillyl alcohol may indeed have effects on biological endpoints. This study will serve as a useful template for examining cell-specific biological endpoints in the testing of future agents that are thought to induce apoptosis in pancreatic cancer