Vigilancia de la resistencia bacteriana en unidades de salud de Hermosillo y Ciudad Obregón, Sonora, México

The objective of this study was to analyze the antibiotic resistance percentages of bacteria collected from health units (HU) in Hermosillo and Ciudad Obregón, Sonora, Mexico. Eight HU from Hermosillo and three HU from Ciudad Obregón, nine belong to the public sector and two to the private sector. Overall, 15,653 results of identification and drug resistance from clinical bacterial isolates were analyzed for a one-year period (2019-2020). Subsequently, a comparative study was carried out for six health units in Hermosillo, for 2014-2015 and 2019-2020 periods. Differences between populations and time periods were assessed through the Chi square test, for differences among populations and time periods. Altogether, for the 2019-2020 period the most frequently isolated microorganisms were Escherichia coli (32.9 %), Klebsiella pneumoniae (8.4 %), Pseudomonas aeruginosa (7.6 %) and Staphylococcus aureus (6.6 %). Different resistance percentages to widely used drugs such as cephalosporins, quinolones and carbapenems were detected. A significant decrease in resistance percentages was observed, in six HU in Hermosillo, for most of the antibiotics tested in 2020, compared to 2015. Significative differences were found in antibiotic resistance between clinical isolates from Hermosillo and Ciudad Obregón, two cities that are separated by only 252 km (156 miles).El objetivo del presente trabajo fue analizar los porcentajes de resistencia a los antibióticos, de bacterias colectadas de unidades de salud (US) en Hermosillo y Ciudad Obregón, Sonora, México. Participaron ocho US de Hermosillo y tres de Ciudad Obregón, nueve pertenecen al sector público y dos al sector privado. Se analizaron los resultados de identificación y drogorresistencia de 15,653 aislamientos en un periodo de un año (2019-2020). Posteriormente, se compararon seis unidades de salud de Hermosillo, para los periodos 2014-2015 y 2019-2020. Las diferencias , entre poblaciones y periodos de tiempo, se obtuvieron mediante chi quadrada. Durante el periodo 2019-2020, los microorganismos más frecuentemente aislados fueron Escherichia coli (32.9 %), Klebsiella pneumoniae (8.4 %), Pseudomonas aeruginosa (7.6 %) y Staphylococcus aureus (6.6 %). Se detectaron diferencias en la resistencia a fármacos ampliamente utilizados como cefalosporinas, quinolonas y carbapenémicos, entre las instituciones de Hermosillo y Ciudad Obregón. En seis unidades de salud de Hermosillo, se observó una disminución en los porcentajes de resistencia para la mayoría de los antibióticos ensayados en 2020, respecto a 2015. Se encontraron diferencias significativas en la resistencia a los antibióticos entre los aislamientos clínicos de Hermosillo y Ciudad Obregón, dos ciudades separadas por sólo 252 km

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements