UC Merced

Ceftolozane/tazobactam (c/t) is a fifth generation β-lactam cephalosporin and β-lactam inhibitor, recently approved in the United States for treatment of complicated Urinary Tract Infections (UTIs) and complicated intra-abdominal infections. While third generation cephalosporins are commonly used for Enterobacteriaceae infection treatment, fourth generation cephalosporins are used less frequently to spare them from rising antibiotic resistance, and fifth generation cephalosporins, such as c/t, are last-resort treatment options. Surveillance for c/t resistance is essential to identifying current resistance patterns and to identify causes of any observed resistance. We performed Kirby-Bauer disk diffusion tests on a collection of Extended Spectrum β-lactamases (ESBL)-producing Enterobacteriaceae collected mainly from urine samples at Dignity Health Mercy Medical Center (DHMMC) in Merced, CA (n = 993), and found low rates of c/t resistance (3.24%). We used a PCR screen to quantify the presence of four common ESBLs (blaTEM, blaOXA, blaSHV, and blaCTX-M) on 852 isolates and assessed their association with c/t resistance. We then screened the genomic sequences of 123 isolates and used PCR to identify the presence of four non-ESBL genes, emrD (gene for efflux pump), ramR (gene for efflux pump repressure), and ompK35 and ompK37 (genes for porins in bacterial outer membrane) in 96 isolates subset. We found that the presence of blaCTX-M, blaSHV independently contributed to c/t resistance. We did not find significant interactions between the non-ESBLs and c/t resistance, nor did we find any significant interactions between having a combination of ESBL and non-ESBL genes with c/t resistance. We then wanted to find the teaching patterns in Science, Technology, Engineering, and Mathematics (STEM) classrooms. We investigated how STEM instructors, who are mainly faculty on the forefront of scientific discoveries, discuss scientific content with their students. We looked at instructional and discourse practices of 35 STEM instructors across variables such as STEM discipline, years of teaching experience, and class size. We found that chemistry instructors used more instructor-centered teaching practices (i.e., lecturing with real world examples) than biology instructors. We also found that teaching faculty use more student-centered teaching practices than lecturers. Additionally, we found that neither years of faculty teaching experience nor class size impacted teaching practices. Investigating resistance patterns to newly available antibiotics is essential for prolonging its efficacy, while studying patterns of effective communication of these scientific findings in undergraduate STEM classrooms are equally important, and both contribute to the betterment of our society.