Correlation between wastewater and COVID-19 case incidence rates in major California sewersheds across three variant periods.

Monitoring for COVID-19 through wastewater has been used for adjunctive public health surveillance, with SARS-CoV-2 viral concentrations in wastewater correlating with incident cases in the same sewershed. However, the generalizability of these findings across sewersheds, laboratory methods, and time periods with changing variants and underlying population immunity has not been well described. The California Department of Public Health partnered with six wastewater treatment plants starting in January 2021 to monitor wastewater for SARS-CoV-2, with analyses performed at four laboratories.

Yersinia ironomics: comparison of iron transporters among Yersinia pestis biotypes and its nearest neighbor, Yersinia pseudotuberculosis.

Although Yersinia pestis epidemic biovars and Yersinia pseudotuberculosis are recently diverged, highly related species, they cause different diseases via disparate transmission routes. Since iron transport systems are important for iron acquisition from hosts and for survival in the environment, we have analyzed potential iron transport systems encoded by epidemic and non-epidemic or endemic strains of Y. pestis as well as two virulent Y.

Insights into Yersinia pestis biofilm development: topology and co-interaction of Hms inner membrane proteins involved in exopolysaccharide production.

Primarily, three operons, hmsHFRS, hmsT and hmsP, are responsible for the development of a Yersinia pestis biofilm, which is essential for blockage-dependent transmission of plague from fleas to mammals. Here, using specific antibodies, a polymeric beta-1,6-N-acetyl-d-glucosamine-like polysaccharide was detected in the extracellular matrix of hmsHFRS-dependent Y. pestis biofilm.

yadBC of Yersinia pestis, a new virulence determinant for bubonic plague.

In all Yersinia pestis strains examined, the adhesin/invasin yadA gene is a pseudogene, yet Y. pestis is invasive for epithelial cells. To identify potential surface proteins that are structurally and functionally similar to YadA, we searched the Y.

Analysis of the aerobactin and ferric hydroxamate uptake systems of Yersinia pestis.

Yersinia pestis genomes contain genes homologous to the aerobactin receptor (iutA) and biosynthetic genes (iucABCD) as well as the ferric hydroxamate uptake system (fhuCDB) of Escherichia coli. However, iucA is disrupted by a frameshift mutation. An E.

Identification of critical amino acid residues in the plague biofilm Hms proteins.

Yersinia pestis biofilm formation causes massive adsorption of haemin or Congo red in vitro as well as colonization and eventual blockage of the flea proventriculus in vivo. This blockage allows effective transmission of plague from some fleas, like the oriental rat flea, to mammals. Four Hms proteins, HmsH, HmsF, HmsR and HmsS, are essential for biofilm formation, with HmsT and HmsP acting as positive and negative regulators, respectively.

Novel perfluoroalkylated derivatives of D-galactopyranose and xylitol for biomedical uses. Hemocompatibility and effect on perfluorocarbon emulsions.

6-O-(4,4,5,5,6,6,7,7,7-Nonafluoro-2-hydroxyheptyl)-, 6-O-(4,4,5,5,6,6,7,7,8,8,9,9,9-tridecafluoro-2-hydroxynonyl)-, and 6-O-(4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11-heptadecafluoro-2-hydroxyundecyl)-d-galactopyranose (9, 10, and 11, resp.) were prepared by a two-step synthesis including the reaction of 1,2:3,4-di-O-isopropylidene-alpha-d-galactopyranose with 2-[(perfluoroalkyl)methyl]oxiranes under catalysis with BF(3).Et(2)O.

Neisseria meningitidis RTX proteins are not required for virulence in infant rats.

RTX cytotoxins play an important role in virulence of numerous gram-negative pathogens. Unexpectedly, however, we show here that the RTX proteins of Neisseria meningitidis are dispensable for virulence in the infant rat model of infection.

Evaluation of toxicity of pesticides and their biodegradation products using human cells.

Juvenoids are biologically active compounds, of relatively low toxicity to humans, that efficiently inhibit the fertility of insects. However, little attention has been paid to the stability and toxicity of products that may be generated by their biodegradation in the ecosystem. This study describes a simple comparison of the toxicity of the active compound and its degradation products generated by aerobic soil microbial isolates.