Passive biomonitoring for per- and polyfluoroalkyl substances using invasive clams, C. fluminea.

Per- and polyfluoroalkyl substances (PFAS) are a class of toxic manufactured chemicals in commercial and consumer products. They are resistant to environmental degradation and mobile in soil, air, and water. This study used the introduced bivalve Corbicula fluminea as a passive biomonitor at sampling locations in a primary drinking water source in Virginia, USA. Many potential PFAS sources were identified in the region. Perfluorohexane sulfonate (PFHxS) and 6:2 fluorotelomer sulfonic acid (6:2 FTS) levels were highest downstream of an airport. The highest levels of short-chain carboxylic acids were in locations downstream of a wastewater treatment plant. Measured PFAS concentrations varied by location in C. fluminea, sediment, and surface water samples. Two compounds were detected across all three mediums. Calculated partitioning coefficients confirm bioaccumulation of PFAS in C. fluminea and sorption to sediment. C. fluminea bioaccumulated two PFAS not found in the other mediums. Perfluoroalkyl carboxylic acids and short-chain compounds dominated in clam tissue, which contrasts with findings of accumulation of longer-chain and perfluorosulfonic acids in fish. These findings suggest the potential for using bivalves to complement other organisms to better understand the bioaccumulation of PFAS and their fate and transport in a freshwater ecosystem.

Hyperkalemia-induced paralysis.

Hyperkalemia is an electrolyte abnormality that can lead to severe consequences. Paralysis induced by hyperkalemia has been described in only a few reports. We describe a 60-year-old man who experienced paralysis presumably due to hyperkalemia. He presented to the emergency department with severe weakness in all extremities. The patient's serum potassium concentration was greater than 8 mEq/L and his serum creatinine concentration was 7 mg/dl. Findings on electrocardiography were abnormal. Of note, his drug therapy included lisinopril and naproxen. After treatment for hyperkalemia, the patient's symptoms resolved; however, he was admitted for further workup for renal failure. The patient was discharged after approximately 1 week with a diagnosis of end-stage renal disease. Use of the Naranjo adverse drug reaction probability scale indicated a probable relationship (score of 5) between the patient's paralysis and hyperkalemia. Although hyperkalemia as a cause of paralysis is extremely rare, clinicians should be aware of this potentially life-threatening, noncardiac toxicity.

Molecular epidemiological analysis and microbial source tracking of Salmonella enterica serovars in a preharvest turkey production environment.

Epidemiological studies were conducted to source track and delineate horizontal transmission pathways of Salmonella serovars in a turkey production environment. Salmonella enterica serovar Heidelberg (n = 111), Salmonella Senftenberg (n = 14), Salmonella Muenster (n = 10), unidentifiable "roughs" (n = 5), Salmonella Anatum (n = 3), and Salmonella Worthington (n = 2) were isolated from the birds' cecal and crop contents, litter, environmental swabs, drinkers, and feed samples. These strains (n = 145) were analyzed for their antimicrobial susceptibility profiles and the bacterial horizontal transmission pathways were tracked by XbaI-digested pulsed-field gel electrophoresis (PFGE) macrorestriction profiles. Nearly 79% of the strains were resistant to one or more antimicrobials, while 44% of the strains were resistant to two to six antimicrobials. Nearly 21% of the strains were susceptible to all of the antimicrobials tested. Twenty-seven distinct PFGE fingerprint profiles (90-95% similarity) were observed among 110 Salmonella Heidelberg strains (one strain was untypeable), and 13 of the 27 profiles (48%) elicited 100% similarity among the fingerprint patterns. The prevalence of Salmonella Heidelberg strains at weeks 2 (n = 20), 10 (n = 20), and 18 (n = 70) among the sampled pens suggested cross-colonization among pens during the 20-week production cycle. Salmonella Heidelberg strains were first isolated from the birds at week 2, and identical fingerprint profiles of this serovar were subsequently isolated from birds within the same pen; birds in other pens; and litter, air, and swab samples at weeks 10 and 18, suggesting possible horizontal transmission of this serovar across the production facility during the grow-out period.

Late life metabolic syndrome, early growth, and common polymorphism in the growth hormone and placental lactogen gene cluster.

Low rates of fetal and infant growth are associated with the metabolic syndrome and cardiovascular disease in later life. We investigated common genetic variation in the GH-CSH gene cluster on chromosome 17q23 encoding GH, placental lactogens [chorionic somatomammotropins (CSH)], and placental GH variant in relation to fetal and infant growth and phenotypic features of the metabolic syndrome in subjects aged 59-72 yr from Hertfordshire, UK. Allele groups T, D1, and D2 of a locus herein designated CSH1.01 were examined in relation to GH-CSH single nucleotide polymorphisms and to specific phenotypes. Average birth weights were similar for all genotype groups. Men with T alleles were significantly lighter at 1 yr of age, shorter as adults, and had higher blood pressures, fasting insulin (T/T 66% higher than D2/D2) and triglyceride concentrations, and insulin and glucose concentrations during a glucose tolerance test. Birth weight and 1-yr weight associations with metabolic syndrome traits were independent of the CSH1.01 effects. Common diversity in GH-CSH correlates with low 1-yr weight and with features of the metabolic syndrome in later life. GH-CSH genotype adds substantially to, but does not account for, the associations between low body weight, at birth and in infancy, and the metabolic syndrome.