University of Texas Southwestern Medical Center

About: University of Texas Southwestern Medical Center is a healthcare organization based out in Dallas, Texas, United States. It is known for research contribution in the topics: Population & Cancer. The organization has 39107 authors who have published 75242 publications receiving 4497256 citations. The organization is also known as: UT Southwestern & UT Southwestern Medical School.

Phase I study of MRX34, a liposomal miR-34a mimic, administered twice weekly in patients with advanced solid tumors

Abstract: Purpose Naturally occurring tumor suppressor microRNA-34a (miR-34a) downregulates the expression of >30 oncogenes across multiple oncogenic pathways, as well as genes involved in tumor immune evasion, but is lost or under-expressed in many malignancies. This first-in-human, phase I study assessed the maximum tolerated dose (MTD), safety, pharmacokinetics, and clinical activity of MRX34, a liposomal miR-34a mimic, in patients with advanced solid tumors. Patients and Methods Adult patients with solid tumors refractory to standard treatment were enrolled in a standard 3 + 3 dose escalation trial. MRX34 was given intravenously twice weekly (BIW) for three weeks in 4-week cycles. Results Forty-seven patients with various solid tumors, including hepatocellular carcinoma (HCC; n = 14), were enrolled. Median age was 60 years, median prior therapies was 4 (range, 1–12), and most were Caucasian (68%) and male (57%). Most common adverse events (AEs) included fever (all grade %/G3%: 64/2), fatigue (57/13), back pain (57/11), nausea (49/2), diarrhea (40/11), anorexia (36/4), and vomiting (34/4). Laboratory abnormalities included lymphopenia (G3%/G4%: 23/9), neutropenia (13/11), thrombocytopenia (17/0), increased AST (19/4), hyperglycemia (13/2), and hyponatremia (19/2). Dexamethasone premedication was required to manage infusion-related AEs. The MTD for non-HCC patients was 110 mg/m2, with two patients experiencing dose-limiting toxicities of G3 hypoxia and enteritis at 124 mg/m2. The half-life was >24 h, and Cmax and AUC increased with increasing dose. One patient with HCC achieved a prolonged confirmed PR lasting 48 weeks, and four patients experienced SD lasting ≥4 cycles. Conclusion MRX34 treatment with dexamethasone premedication was associated with acceptable safety and showed evidence of antitumor activity in a subset of patients with refractory advanced solid tumors. The MTD for the BIW schedule was 110 mg/m2 for non-HCC and 93 mg/m2 for HCC patients. Additional dose schedules of MRX34 have been explored to improve tolerability.

A rapid and simple procedure for chronic cannulation of the rat jugular vein.

Abstract: PLASMA LEVELS OF PITUITARYHORMONES are affected by the method used for blood collection. These alterations are due at least in part to the stress of handling and/or anesthesia (1, 8, 14). Recent studies (4, 6) also indicate that hormone levels may fluctuate in a circhoral pattern under normal physiologic conditions. Consequently, for studies on physiologic plasma levels of the pituitary hormones, it is necessary to obtain sequential blood samples without disturbing the animal. Such studies in the rat have been hampered by the lack of simple effective procedures for chronic blood vessel catherization. Venous or arterial cannulas have been described for the rat; however, the majority of such cannulas are less than easy to prepare and/or their implantation is laborious (3, 5, 9, 12, 13). The present communication describes a cannula that is easy to prepare and a cannulation procedure that is simple and fast.

Decreased segregation of brain systems across the healthy adult lifespan

Abstract: Healthy aging has been associated with decreased specialization in brain function. This characterization has focused largely on describing age-accompanied differences in specialization at the level of neurons and brain areas. We expand this work to describe systems-level differences in specialization in a healthy adult lifespan sample (n = 210; 20–89 y). A graph-theoretic framework is used to guide analysis of functional MRI resting-state data and describe systems-level differences in connectivity of individual brain networks. Young adults’ brain systems exhibit a balance of within- and between-system correlations that is characteristic of segregated and specialized organization. Increasing age is accompanied by decreasing segregation of brain systems. Compared with systems involved in the processing of sensory input and motor output, systems mediating “associative” operations exhibit a distinct pattern of reductions in segregation across the adult lifespan. Of particular importance, the magnitude of association system segregation is predictive of long-term memory function, independent of an individual’s age.