Polyethylene terephthalate textile heart valve: How poly(ethylene glycol) grafting limits fibrosis.

Transcatheter aortic valve replacement (TAVR) is an alternative technique to surgical valve replacement for over 300,000 patients worldwide. The valve material used in the TAVR is made of biological tissues, whose durability remains unknown. The success of the TAVR favors the research toward synthetic valve leaflet materials as an alternative to biological tissues.

Competency-based education in general surgery: Are Canadian residents ready?

Competency-based education (CBE) is currently being implemented by the Royal College of Physicians and Surgeons of Canada across all residency programs. This shift away from time-based residency is proposed to be the answer to maximize training opportunity in the era of work hour restrictions and growing concerns regarding accountability in medical education. A Web-based survey was conducted to obtain feedback from Canadian general surgery residents on their experience and perception of competence within core procedures, as well as attitudes toward CBE.

Gastrostomy Tube for Nutrition and Malignant Bowel Obstruction in Patients With Cancer.

Background: Gastrostomy tubes (G-tubes) are invaluable clinical tools that play a role in palliation and nutrition in patients with cancer. This study aimed to better understand the risks and benefits associated with the placement and maintenance of G-tubes.

Methods: Patients who underwent placement of a G-tube for cancer from January 2013 through December 2017 at a tertiary care center were considered for inclusion.

Primary tumor characteristics and next-generation sequencing mutations as biomarkers for melanoma immunotherapy response.

Introduction: Considerable advances in melanoma have been realized through immunotherapy. The principal aim was to determine whether primary tumor characteristics or next-generation sequencing (NGS) could serve as markers of immunotherapy response.

Methods And Results: The study cohort consisted of 67 patients who received immunotherapy for recurrent or metastatic melanoma and for whom primary tumor biopsies and pathology reports were available.

Treatment times in breast cancer patients receiving neoadjuvant vs adjuvant chemotherapy: Is efficiency a benefit of preoperative chemotherapy?

Background/objective: Delays in times to surgery, chemotherapy, and radiotherapy impair survival in breast cancer patients. Neoadjuvant chemotherapy (NAC) confers equivalent survival to adjuvant chemotherapy (AC), but it remains unknown which approach facilitates faster initiation and completion of treatment.

Methods: Women ≥18 years old with nonrecurrent, noninflammatory, clinical stage I-III breast cancer diagnosed between 2004 and 2015 who underwent both surgery and chemotherapy were reviewed from the National Cancer Database.

Real-time electromagnetic navigation for breast-conserving surgery using NaviKnife technology: A matched case-control study.

Breast-conserving surgery (BCS) is a mainstay in breast cancer treatment. For nonpalpable breast cancers, current strategies have limited accuracy, contributing to high positive margin rates. We developed NaviKnife, a surgical navigation system based on real-time electromagnetic (EM) tracking.

Callosal Sensitivity to Short-Range Stimulus Orientation and Long-Range Stimulus Context Orientation: Tachistoscopic Evidence.

To study local-global relationships in interhemispheric interactions, tachistoscopically presented pairs of lines (1.15 degrees) were compared for their relative orientation by 48 neurotypical adults. Orientations of line stimuli (local aspect of the task) were vertical, horizontal, forward slash or backslash, as were those of the interstimulus axes.

Navigated Breast Tumor Excision Using Electromagnetically Tracked Ultrasound and Surgical Instruments.

Objective: Lumpectomy, breast conserving tumor excision, is the standard surgical treatment in early stage breast cancer. A common problem with lumpectomy is that the tumor may not be completely excised, and additional surgery becomes necessary. We investigated if a surgical navigation system using intraoperative ultrasound improves the outcomes of lumpectomy and if such a system can be implemented in the clinical environment.

A unique presentation of a standard type C esophageal atresia in a very low-birth-weight neonate.

Neonates with esophageal atresia and tracheoesophageal fistula usually present with inability to swallow immediately after birth often associated with respiratory distress. This is an unusual presentation of a very low-birth-weight neonate with a type C tracheoesophageal fistula that was fed for the first 4 days of life through an unintentional tracheogastric tube without incident.

Gamma irradiation of animal sera for inactivation of viruses and mollicutes--a review.

Animal-derived materials such as animal sera represent a low, but finite, risk for introduction of an adventitious agent (virus or mollicute) into a biological bulk harvest during upstream manufacturing processes involving mammalian cell substrates. Viral and mollicute (Mycoplasma sp. and Acholeplasma sp.

New variations of intrahemispheric and interhemispheric processing indexed by the dimond paradigm.

We report 2 experiments designed to demonstrate that unilateral tachistoscopic stimulation would yield a response time (RT) advantage over bilateral stimulation in a simple experiment, whereas the opposite pattern would occur in a complex version of the same task, as predicted by the intrahemispheric resource limitation model of Banich and colleagues. Experiment 1 was a go/no-go task in which participants had to press a key when two shapes (circles or squares) were identical on the computer screen. A unilateral field advantage was obtained that was accentuated in several task conditions that yielded overall longer RTs, mostly in the bilateral condition.

Gamma-irradiation of serum for the inactivation of adventitious contaminants.

Assurance of viral and mycoplasma safety in biopharmaceuticals is best achieved through elimination of animal-derived materials from the manufacturing process. Where this is not possible, the risk of introducing a contaminant through use of the material must be assessed and mitigated. Bovine-sourced serum represents an animal-derived material that is required for certain biopharmaceutical manufacturing processes.

Staphylococcus aureus strain typing by single-molecule DNA mapping in fluidic microchips with fluorescent tags.

Background: Epidemiologic studies require identification or typing of microbial strains. Macrorestriction DNA mapping analyzed by pulsed-field gel electrophoresis (PFGE) is considered the current gold standard of genomic typing. This technique, however, is difficult to implement because it is labor-intensive and difficult to automate, it requires a long time to obtain results, and results often vary between laboratories.

Alternative splicing yields protein arginine methyltransferase 1 isoforms with distinct activity, substrate specificity, and subcellular localization.

PRMT1 is the predominant member of a family of protein arginine methyltransferases (PRMTs) that have been implicated in various cellular processes, including transcription, RNA processing, and signal transduction. It was previously reported that the human PRMT1 pre-mRNA was alternatively spliced to yield three isoforms with distinct N-terminal sequences. Close inspection of the genomic organization in the 5'-end of the PRMT1 gene revealed that it can produce up to seven protein isoforms, all varying in their N-terminal domain.

A mouse model of human breast cancer metastasis to human bone.

Currently, an in vivo model of human breast cancer metastasizing from the orthotopic site to bone does not exist, making it difficult to study the many steps of skeletal metastasis. Moreover, models used to identify the mechanisms by which breast cancer metastasizes to bone are limited to intracardiac injection, which seeds the cancer cells directly into the circulation, thus bypassing the early steps in the metastatic process. Such models do not reflect the full process of metastasis occurring in patients.

Validation of the heat treatment step used in the production of diaspirin crosslinked hemoglobin (DCLHb) for viral inactivation--effect of crosslinking.

Two experiments were performed to assess viral inactivation during the crosslinking and heat treatment steps of the DCLHb manufacturing process. Stroma free hemoglobin (SFHb) collected from a large scale manufacturing lot was tested in a 1:680 scaled down system in which the key parameters used in the manufacturing process were replicated. In the first study Porcine Parvovirus (PPV), a non-enveloped virus, was used to assess inactivation, while in the second study Bovine Viral Diarrhea Virus (BVDV), an enveloped virus, was utilized.