This literature review examines the increase in antibiotic resistance in Escherichia coli, a Gram-negative bacterium that frequently causes infections in humans and animals. Although most E. coli strains are harmless, some pathogenic strains have shown resistance to various antibiotics, posing a significant challenge in the healthcare field. This study highlights the various resistance mechanisms found in E. coli, including the production of ?-lactamase enzymes that can inactivate antibiotics, modification of antibiotic targets, changes in membrane permeability, and increased activity of efflux pumps that expel antibiotics from bacterial cells. Additionally, this review discusses factors contributing to the spread of resistance, such as the excessive and inappropriate use of antibiotics in medicine and livestock, and the transfer of resistance genes through mobile genetic elements. The literature highlights recent research efforts to address this issue, including the development of new antibiotics, the use of antibiotic combinations, and alternative therapies such as bacteriophages and specific enzyme inhibitors. This review emphasizes the importance of strict surveillance and prudent antibiotic use policies to prevent the further spread of antibiotic resistance in E. coli, ensuring the effectiveness of bacterial infection treatments in the future.

This study aims to analyze the comparison of stock prices and volume at PT. Kalbe Farma Tbk before and during covid-19 pandemic. Type of this research used is descriptive quantitative analysis. Data analysis techniques using Paired Simple T-Test with SPSS 25. Based on the results of the Paired Sample T-Test on the stock price of PT. Kalbe Farma Tbk can be concluded that the significance value is 0.733 (p > 0.05). So Hi is rejected, Ho is accepted, which means there is no significant difference to the stock price of PT. Kalbe Farma Tbk, before and during the covid-19 pandemic. Based on the results of the Paired Sample T-Test on the stock volume of PT. Kalbe Farma Tbk can be concluded that the significance value is 0.043 (p < 0.05). So, Hi is accepted, Ho is rejected, which means that there is a significant difference in share volume.