Impact of neoadjuvant therapy on nodal harvest in clinical stage III rectal cancer: Establishing optimum cut-offs by disease response.

Introduction: A minimum lymph node harvest (LNH) of 12 is the current standard for appropriate nodal staging in resectable rectal cancer. However, the rise of neoadjuvant chemoradiation (NCRT) and total neoadjuvant therapy (TNT) has been associated with decreasing number of LNH. We hypothesize that as tumor response to neoadjuvant therapy increases, the optimum for LNH to achieve appropriate nodal staging should decrease.

Induced organoids derived from patients with ulcerative colitis recapitulate colitic reactivity.

The pathogenesis of ulcerative colitis (UC), a major type of inflammatory bowel disease, remains unknown. No model exists that adequately recapitulates the complexity of clinical UC. Here, we take advantage of induced pluripotent stem cells (iPSCs) to develop an induced human UC-derived organoid (iHUCO) model and compared it with the induced human normal organoid model (iHNO).

A Tissue Engineering Approach to Metastatic Colon Cancer.

Colon cancer remains the third most common cause of cancer in the US, and the third most common cause of cancer death. Worldwide, colon cancer is the second most common cause of cancer and cancer deaths. At least 25% of patients still present with metastatic disease, and at least 25-30% will develop metastatic colon cancer in the course of their disease.

Organoid Models of Colorectal Pathology: Do They Hold the Key to Personalized Medicine? A Systematic Review.

Background: Colorectal cancer and IBD account for a large portion of the practice of colorectal surgery. Historical research models have provided insights into the underlying causes of these diseases but come with many limitations.

Objective: The aim of this study was to systematically review the literature regarding the advantage of organoid models in modeling benign and malignant colorectal pathology.

Shelter type and birth number influence the birth and death sites of lambs and ewe movement around lambing time.

A significant number of lambs born each yr in Australia die within 72 h of birth. Periods of high wind, combined with rain and low temperatures, can lead to marked increases in the level of mortality. Under these weather conditions mortality levels may be reduced with the provision of shelter, provided it is utilized by lambs.

A Comparison of Internal Dispositions and Career Trajectories after Collaborative versus Apprenticed Research Experiences for Undergraduates.

Undergraduate research experiences confer benefits on students bound for science, technology, engineering, and mathematics (STEM) careers, but the low number of research professionals available to serve as mentors often limits access to research. Within the context of our summer research program (BRAIN), we tested the hypothesis that a team-based collaborative learning model (CLM) produces student outcomes at least as positive as a traditional apprenticeship model (AM). Through stratified, random assignment to conditions, CLM students were designated to work together in a teaching laboratory to conduct research according to a defined curriculum led by several instructors, whereas AM students were paired with mentors in active research groups.

Esophagogastric junction distensibility is greater following Toupet compared to Nissen fundoplication.

Background: The goal of antireflux surgery is to create a competent antireflux valve at the esophagogastric junction (EGJ). The two most common types of fundoplications constructed are the 360° Nissen and the 270° Toupet. We sought to determine whether there was a significant difference in distensibility at the EGJ based on fundoplication geometry (full vs.

Limited Hiatal Dissection Without Fundoplication Results in Comparable Symptomatic Outcomes to Laparoscopic Heller Myotomy with Anterior Fundoplication.

Background: Previous randomized controlled trials have demonstrated that partial fundoplication following Heller myotomy results in less pathologic acid exposure to the esophagus when compared to myotomy without fundoplication. Recent studies have questioned the necessity of a fundoplication, especially when a limited hiatal dissection (LHD) is performed and the angle of His is preserved.

Materials And Methods: This is a retrospective review of prospectively maintained data.

Intraoperative Assessment of Esophagogastric Junction Distensibility During Laparoscopic Heller Myotomy.

We sought to characterize the changes in esophagogastric junction (EGJ) distensibility during Heller Myotomy with Dor fundoplication using the EndoFLIP device. Intraoperative distensibility measurements on 14 patients undergoing Heller myotomy with Dor fundoplication were conducted over an 18-month period. Minimum esophageal diameter, cross-sectional areas, and distensibility index were measured at 30 and 40 mL catheter volumes before myotomy, postmyotomy, and following Dor fundoplication.

Ewe and lamb contact at lambing is influenced by both shelter type and birth number.

A significant number of lambs born each year in Australia die within 72 h of birth. Periods of high wind, combined with rain and low temperatures can lead to marked increases in the mortality level. Under these climatic conditions mortality levels may be reduced with the provision of shelter.

Providing undergraduate science partners for elementary teachers: benefits and challenges.

Undergraduate college "science partners" provided content knowledge and a supportive atmosphere for K-5 teachers in a university-school professional development partnership program in science instruction. The Elementary Science Education Partners program, a Local Systemic Change initiative supported by the National Science Foundation, was composed of four major elements: 1) a cadre of mentor teachers trained to provide district-wide teacher professional development; 2) a recruitment and training effort to place college students in classrooms as science partners in semester-long partnerships with teachers; 3) a teacher empowerment effort termed "participatory reform"; and 4) an inquiry-based curriculum with a kit distribution and refurbishment center. The main goals of the program were to provide college science students with an intensive teaching experience and to enhance teachers' skills in inquiry-based science instruction.

Teaching creativity and inventive problem solving in science.

Engaging learners in the excitement of science, helping them discover the value of evidence-based reasoning and higher-order cognitive skills, and teaching them to become creative problem solvers have long been goals of science education reformers. But the means to achieve these goals, especially methods to promote creative thinking in scientific problem solving, have not become widely known or used. In this essay, I review the evidence that creativity is not a single hard-to-measure property.

An assessment of chromosomal alterations detected by fluorescence in situ hybridization and p16 expression in sporadic and primary sclerosing cholangitis-associated cholangiocarcinomas.

The objective of this study was to assess and compare the chromosome abnormalities present in sporadic and primary sclerosing cholangitis (PSC)-associated cholangiocarcinomas (CCAs) and biliary dysplasias. Histologic sections from 22 patients with CCA (16 sporadic and 6 PSC associated), 5 of whom had associated dysplasia, and 2 PSC patients with biliary dysplasia alone were assessed for chromosomal alterations with fluorescence in situ hybridization (FISH). FISH involved the use of a multiprobe set consisting of centromere-specific probes for chromosomes 3, 7, and 17 and a locus-specific probe for 9p21.

Routes to research for novice undergraduate neuroscientists.

Undergraduate students may be attracted to science and retained in science by engaging in laboratory research. Experience as an apprentice in a scientist's laboratory can be effective in this regard, but the pool of willing scientists is sometimes limited and sustained contact between students and faculty is sometimes minimal. We report outcomes from two different models of a summer neuroscience research program: an Apprenticeship Model (AM) in which individual students joined established research laboratories, and a Collaborative Learning Model (CLM) in which teams of students worked through a guided curriculum and then conducted independent experimentation.

Regulation of p53 target gene expression by cisplatin-induced extracellular signal-regulated kinase.

The extracellular signal-regulated kinase (ERK) pathway is among several signal transduction pathways that are activated in response to exposure to the DNA damage-inducing chemotherapeutic agent cisplatin. We have previously reported that inhibition of cisplatin-induced ERK activity enhances sensitivity to cisplatin. Furthermore, we have demonstrated that cisplatin-induced ERK activation is required for optimal p53 protein accumulation following cisplatin-induced DNA damage.

Prolonged wild-type p53 protein accumulation and cisplatin resistance.

The major limitation for the chemotherapeutic use of DNA-damaging agent cisplatin is the development of resistance in initially responsive tumors. One of the main pathways regulating cell survival following DNA damage is the p53 pathway. In this study we compared the cisplatin-induced response of p53 protein and its downstream targets p21WAF-1 and Mdm2 in the cisplatin-sensitive ovarian carcinoma cell line A2780 and its cisplatin-resistant derivative CP70.

Expression and regulation of cytochrome P450 enzymes in primary cultures of human hepatocytes.

The aim of this study was to test suitable culture conditions for maintaining normal cellular cytoarchitecture and inducibility of P450 enzymes in primary cultures of human hepatocytes by prototypical inducers. The selectivity and sensitivity of a sandwich culture system were determined by treating cultures with a number of clinically relevant drugs that are known to be inducers of either rodent and/or human P450 enzymes. The results showed that considerable induction of CYP3A4 activity is observed at DMSO concentrations greater than 0.

Effect of cryopreservation on cytochrome P-450 enzyme induction in cultured rat hepatocytes.

In the present study, we evaluated the inducibility of cytochrome P-450 (CYP) CYP1A, CYP2B, CYP3A, and CYP4A by beta-naphthoflavone, phenobarbital, dexamethasone, and clofibric acid, respectively, in primary hepatocyte cultures prepared from both fresh and cryopreserved rat hepatocytes. Rat hepatocytes were successfully thawed and cultured after cryopreservation in liquid nitrogen for up to 1 month. Percentage of total recovery, viable cell recovery, and final viability of the cells were 68%, 72%, and 85%, respectively.

Asymmetric voltage dependence of embryonic cardiac gap junction channels.

The voltage dependence of junctional conductance (Gj) and the unitary channel behavior of junctions in most pairs of 3-day, 7-day, and 18-day embryonic chick heart cells are symmetrical, i.e., they are independent of the direction of polarization of junctional potential (Vj).

Specific motifs in the external loops of connexin proteins can determine gap junction formation between chick heart myocytes.

1. Gap junction formation was compared in the absence and presence of small peptides containing extracellular loop sequences of gap junction (connexin) proteins by measuring the time taken for pairs of spontaneously beating embryonic chick heart myoballs to synchronize beat rates. Test peptides were derived from connexin 32.

Temperature dependence of embryonic cardiac gap junction conductance and channel kinetics.

We have investigated the effects of temperature on the conductance and voltage-dependent kinetics of cardiac gap junction channels between pairs of seven-day embryonic chick ventricle myocytes over the range of 14-26 degrees C. Records of junctional conductance (Gj) and steady-state unit junctional channel activity were made using the whole-cell double patch-clamp technique while the bath temperature was steadily changed at a rate of about 4 degrees C/min. The decrease in Gj upon cooling was biphasic with a distinct break at 21 degrees C.