The bridge helix of Cas12a imparts selectivity in cis-DNA cleavage and regulates trans-DNA cleavage.

Cas12a is an RNA-guided DNA endonuclease of the type V-A CRISPR-Cas system that has evolved convergently with the type II Cas9 protein. We previously showed that proline substitutions in the bridge helix (BH) impart target DNA cleavage selectivity in Streptococcus pyogenes (Spy) Cas9. Here, we examined a BH variant of Cas12a from Francisella novicida (FnoCas12a ) to test mechanistic conservation.

Surface-Treated Pellethanes: Comparative Quantification of Encrustation in Artificial Urine Solution.

Encrustation of implanted urinary tract devices is associated with significant morbidity. Pellethane is a polyether-based compound noted for its strength, porosity, and resistance to solvents. We assessed Pellethane thermoplastic polyurethane (TPU) with and without surface coatings 2-hydroxyethyl methacrylate (HEMA) and tetraethylene glycol dimethyl ether (TETRA) for the potential to resist encrustation in an artificial urine environment.

Evaluation of a point-of-care ultrasound curriculum taught by medical students for physicians, nurses, and midwives in rural Indonesia.

Purpose: In the Indonesian health-care system, nurses and midwives often serve as the primary health-care providers due to physician shortages. Seeking to address the need for medical care in resource-limited environments, some have advocated for portable equipment in the hands of health-care providers. We hypothesized that medical students are able to effectively teach point-of-care ultrasound (POCUS) to physicians, nurses, and midwives in rural Indonesia.

Energy-Mediated Machinery Drives Cellular Mechanical Allostasis.

Allostasis is a fundamental biological process through which living organisms achieve stability via physiological or behavioral changes to protect against internal and external stresses, and ultimately better adapt to the local environment. However, an full understanding of cellular-level allostasis is far from developed. By employing an integrated micromechanical tool capable of applying controlled mechanical stress on an individual cell and simultaneously reporting dynamic information of subcellular mechanics, individual cell allostasis is observed to occur through a biphasic process; cellular mechanics tends to restore to a stable state through a mechanoadaptative process with excitative biophysical activity followed by a decaying adaptive phase.

Metastatic neoplasms to the thyroid diagnosed by fine-needle aspiration/core needle biopsy: Clinicopathologic and cytomorphologic correlation.

Background: Although thyroid fine-needle aspiration (FNA) and core needle biopsy (CNB) are commonly utilized modalities in the evaluation of thyroid nodules, metastatic tumors to the thyroid are only rarely encountered. We aspired to determine the incidence and primary origin of metastases to the thyroid at our institution and to examine their clinicopathologic and cytomorphologic features.

Materials And Methods: A search of our database was undertaken to review all thyroid FNA and/or CNB examined between January 2004 and December 2013.