Reduced Myc overexpression and normal B-cell differentiation mediate resistance to avian leukosis virus lymphomagenesis.

Avian leukosis virus (ALV) induces bursal lymphoma in tumor-susceptible chicken strains after proviral integration within the c-myc gene, and subsequent expansion of Myc-overexpressing lymphocytes within transformed follicles. Line 6(3) strain chickens are resistant to ALV tumorigenesis, largely failing to develop Myc-transformed follicles, although they show similar levels of ALV infection and integration as lymphoma-susceptible strains. Immunohistochemical analysis determined that the transformed follicles that do arise in lymphoma-resistant birds show much lower and more variable Myc overexpression than those of susceptible birds.

Issues surrounding professional portfolio development for nurses.

This article discusses issues that underpin professional portfolio development for registered nurses. The findings were informed by a review of the pertinent literature. The literature was obtained by undertaking searches of a number of electronic databases and hand searches of key journals.

Does setting specific goals and providing feedback during training result in better acquisition of laparoscopic skills?

The aim of this study was to evaluate whether setting specific goals and providing feedback stimulates trainees to improve their laparoscopic skills. Two groups of eight fourth-year medical students practiced on a MIST-VR trainer, a black box laparoscopic suturing trainer, and computer-based training modules for 30 minutes, twice a week for 3 weeks. A precourse assessment of laparoscopic and open suturing skills and performance of MIST-VR tasks was obtained.

Glutamate transmission and addiction to cocaine.

A variety of data point to the possibility that neuroadaptations in glutamate transmission are produced by repeated exposure to cocaine that result in the expression of behaviors characteristic of addiction, such as craving and relapse. Using the reinstatement model of relapse in rats, glutamate release in the projection from the prefrontal cortex to the nucleus accumbens has been shown to underlie cocaine- and stress-primed reinstatement. In this report, four adaptations produced by withdrawal from repeated cocaine are described that may regulate the release of glutamate underlying reinstatement of drug-seeking resulted.

Effect of neonatal rat bisphenol a exposure on performance in the Morris water maze.

Bisphenol A (BPA), an environmental estrogen, is a component of many food and beverage containers and can leach into the container contents over time. Due to its estrogenic properties, exposure to BPA during development could alter the appropriate maturation of pathways essential for normal cognitive function at later ages. To investigate this, the effects of repeated postnatal exposure of male and female rats to BPA on spatial learning and memory were investigated using a Morris water maze.

Preoperative factors predictive of complicated postoperative management after Roux-en-Y gastric bypass for morbid obesity.

Introduction: This study was undertaken to determine preoperative predictive factors of complicated postoperative management after Roux-en-Y gastric bypass (RYGB) for morbid obesity.

Methods: Between January 1999 and January 2002, 158 patients who underwent a RYGB received a standardized preoperative evaluation and data were collected prospectively. Complicated postoperative management was defined as patients requiring postoperative ICU admission for > or =48 h, or those needing transfer from the floor to the ICU.

Laparoscopic resection of posterior duodenal bulb carcinoid tumor.

Duodenal carcinoid tumors are rare neuroendocrine foregut tumors that, in contrast to midgut carcinoid tumors, have a low metastatic potential. The majority can be resected endoscopically. This case details a 67-year old man presenting with a biopsy-proven carcinoid tumor located at the posterior superior aspect of the duodenal bulb which was not amenable to endoscopic resection.

Biosynthetic studies on the alpha-glucosidase inhibitor acarbose: the chemical synthesis of isotopically labeled 2-epi-5-epi-valiolone analogs.

2-epi-5-epi-valiolone is a cyclization product of the C(7) sugar phosphate, sedoheptulose 7-phosphate, involved in the biosynthesis of the aminocyclitol moieties of acarbose, validamycin, and pyralomicin. As part of our investigation into the pathway from 2-epi-5-epi-valiolone to the valienamine moiety of acarbose, we prepared 1-epi-5-epi-(6-(2)H(2))valiolol [(6-(2)H(2))-6], 5-epi-(6-(2)H(2))valiolol [(6-(2)H(2))-17], 1-epi-2-epi-5-epi-(6-(2)H(2))valiolol [(6-(2)H(2))-12] and 2-epi-5-epi-(6-(2)H(2))valiolamine [(6-(2)H(2))-11]. Compounds (6-(2)H(2))-6 and (6-(2)H(2))-17 were synthesized from 2,3,4,6-tetra-O-benzyl-D-glucopyranose in 10 and seven steps, respectively, whereas (6-(2)H(2))-12 and (6-(2)H(2))-11 were synthesized from 2,3,4,6-tetra-O-benzyl-D-mannopyranose in eight and 10 steps, respectively.

Photoperiod alters the time course of brain cyclooxygenase-2 expression in Siberian hamsters.

Fever is initiated by activation of the arachidonic acid cascade and the biosynthesis of prostaglandins within the brain. Inducible cyclooxygenase (COX-2) is a rate-limiting enzyme in prostaglandin synthesis, and the number of blood vessels expressing COX-2 correlates with elevated body temperature following peripheral lipopolysaccharide (LPS). Despite its importance in host defense, fever is energetically expensive and we hypothesized that fever may be limited by available metabolic resources.

Psychomotor skills assessment in practicing surgeons experienced in performing advanced laparoscopic procedures.

Background: Minimally invasive surgery (MIS) has introduced a new and unique set of psychomotor skills for a surgeon to acquire and master. Although assessment technologies have been proposed, precise and objective psychomotor skills assessment of surgeons performing laparoscopic procedures has not been detailed.

Study Design: Two hundred ten surgeons attending the 2001 annual meeting of the American College of Surgeons in New Orleans who reported having completed more than 50 laparoscopic procedures participated.

Silent point mutation in an avian retrovirus RNA processing element promotes c-myb-associated short-latency lymphomas.

The avian leukosis virus DeltaLR-9 causes a high frequency of B-cell lymphomas within weeks after injection into 10-day-old chicken embryos. These lymphomas result from proviral integrations into the oncogene c-myb. In contrast, LR-9, which lacks the 42-nucleotide gag gene deletion of DeltaLR-9, does not cause a high frequency of c-myb-associated short-latency lymphomas.

The major cold shock gene, cspA, is involved in the susceptibility of Staphylococcus aureus to an antimicrobial peptide of human cathepsin G.

A Tn551 insertional library of Staphylococcus aureus strain ISP479 was challenged with an antimicrobial peptide (CG 117-136) derived from human neutrophil cathepsin G (CG). After repeated selection and screening of surviving colonies, a mutant was identified that expressed increased resistance to CG 117-136. Southern hybridization analysis revealed that the Tn551 insert in this mutant (SK1) was carried on a 10.

Can current technology be integrated to facilitate laparoscopic living donor hepatectomy?

Background: Living donor hepatectomy (LDH) is a technically demanding procedure that is an alternative for providing livers for transplantation. Unlike liver resections for other pathology, LDH requires preservation of the major vessels and biliary tree. This study was performed to determine if current technology can be integrated to perform laparoscopic LDH.

Variability of total phenytoin serum concentrations within elderly nursing home residents.

Background: Approximately 6% of all elderly nursing home residents receive phenytoin. Phenytoin concentrations are often measured to guide therapy.

Objective: To evaluate the intraresident variability among multiple measurements of total phenytoin serum concentrations in nursing home residents.

Functional genomic analysis reveals distinct neoplastic phenotypes associated with c-myb mutation in the bursa of Fabricius.

Avian retroviral integration into the c-myb locus is casually associated with the development of lymphomas in the bursa of Farbricius of chickens; these arise with a shorter latency than bursal lymphomas caused by deregulation of c-myc. This study indicates that c-myb mutation in embryonic bursal precursors leads to an oligoclonal population of developing bursal follicles, showing a variable propensity to form a novel lesion, the neoplastic follicle (NF). About half of such bursas rapidly developed lymphomas.

Gastrojejunostomy during laparoscopic gastric bypass: analysis of 3 techniques.

Hypothesis: Although perceived as a more technically demanding and time-consuming technique, the hand-sewn gastrojejunostomy during laparoscopic Roux-en-Y gastric bypass (RYGB) is associated with fewer complications and lower costs than stapled techniques.

Design: A retrospective medical record review of prospectively collected data.

Setting: University hospital.

The effects of GnRH administration postinsemination on serum concentrations of progesterone and pregnancy rates in dairy cattle exposed to mild summer heat stress.

The objective of this study was to evaluate whether administration of GnRH postinsemination would improve reproductive performance in heat-stressed dairy cattle. Estrous cycles of Holstein cows were synchronized using the OvSynch protocol and cows were artificially inseminated. Cows were then administered the following treatments: control (no GnRH; n=37), GnRH (100 microg) on Day 5 (GnRH-D5; n=34), or GnRH (100 microg) on Day 11 (GnRH-D11; n=34) postinsemination.

The increased bactericidal activity of a fatty acid-modified synthetic antimicrobial peptide of human cathepsin G correlates with its enhanced capacity to interact with model membranes.

The bactericidal potency of a synthetic peptide (CG 117-136) of human lysosomal cathepsin G (cat G) can be substantially increased by covalent attachment to its N- or C-termini, of saturated, linear fatty acids (FAs), namely those with C-8, C-10 and C-12 hydrocarbon chains. In order to understand better the mechanism by which FA moieties increase the bactericidal activity of CG 117-136, the interaction of N-terminally FA-modified peptides with artificial membranes was studied. First, the content of secondary structure motifs in the modified and unmodified peptides was determined by circular dichroism (CD).

Gallbladder function before and after fundoplication.

No study has reported an association between gastroesophageal reflux disease (GERD) or its therapies and gallbladder function. We compared pre- and postoperative gallbladder function in patients undergoing fundoplication to determine the following: (1) whether patients with chronic GERD have preexisting gallbladder motor dysfunction; (2) whether medical or surgical therapy alters gallbladder function; and (3) whether division of the hepatic branch of the anterior vagus nerve is detrimental to gallbladder motility. Nineteen patients with documented GERD consented to a preoperative cholecystokinin-stimulated technetium hepatobiliary (CCK-HIDA) scan to quantify the gallbladder ejection fraction (GBEF).

KTP laser ablation of Barrett's esophagus after anti-reflux surgery results in long-term loss of intestinal metaplasia. Potassium-titanyl-phosphate.

Background: Efforts to ablate Barrett's epithelium have met with mixed results. We report the long-term follow-up evaluation of the preliminary cohort of patients who underwent thermal ablation of Barrett's epithelium with the potassium-titanyl-phosphate (KTP) laser after anti-reflux surgery.

Methods: Nine patients with intestinal metaplasia (IM) of the esophagus underwent fundoplication (7 laparoscopic Nissen, 1 laparoscopic Toupet, 1 open Nissen) between May 1993 and October 1994.

Biosynthesis of the cyclitol moiety of pyralomicin 1a in Nonomuraea spiralis MI178-34F18.

The biosynthetic pathway leading to the cyclitol moiety of pyralomicin 1a (1) in Nonomuraea spiralis MI178-34F18 has been studied using a series of 2H-labeled potential precursors. The results demonstrate that 2-epi-5-epi-valiolone (7), a common precursor for acarbose (4) and validamycin A (5) biosynthesis, is an immediate precursor of pyralomicin 1a. 5-epi-Valiolone (8) was also incorporated into 1, albeit less efficiently than 7.

Prospective randomized clinical trial comparing nitrous oxide and carbon dioxide pneumoperitoneum for laparoscopic surgery.

Background: Recent publications demonstrating the safety and advantages of N2O for pneumoperitoneum (PP) prompted us to reconsider N2O as an agent for PP in general surgical laparoscopy. The purpose of this prospective, double-blind, randomized clinical trial was to determine whether N2O PP has any benefits over CO2 PP.

Study Design: One hundred three patients received N2O (group I, n = 52) or CO2 (group II, n = 51) PP for elective laparoscopic surgery.

Internal hernia formation after laparoscopic Roux-en-Y gastric bypass for morbid obesity.

There is mounting concern that internal hernia formation after laparoscopic Roux-en-Y gastric bypass (LRYGB) for morbid obesity remains unrecognized until complications develop. In this report we present our experience with this complication. Out of 100 patients who underwent LRYGB we identified five patients who were diagnosed with postoperative internal hernia formation.

Clinical and histologic follow-up after antireflux surgery for Barrett's esophagus.

There are few prospective studies that document the histologic follow-up after antireflux surgery in patients with Barrett's esophagus, as defined by the recently standardized criteria. We report the clinical, endoscopic, and histologic results of patients with Barrett's esophagus followed postoperatively for at least 2 years. Diagnosis of Barrett's esophagus required preoperative endoscopic evidence of columnar-lined epithelium in the esophagus and a biopsy demonstrating specialized intestinal metaplasia, which stains positively with Alcian blue stain.

Long-term outcome of laparoscopic repair of paraesophageal hernia.

Background: It has been reported that the laparoscopic repair of paraesophageal hernias is associated with higher complication and recurrence rates than the open methods of repair.

Methods: We identified 136 consecutive patients who underwent laparoscopic repair of a paraesophageal hernia between 1993 and 1999. Patient demographics and symptom scores for regurgitation, heartburn, chest pain, and dysphagia at presentation and at last follow-up were recorded (0 = none, 1 = mild, 2 = moderate, 3 = severe).