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Foodborne diseases have large economic and societal impacts worldwide. To evaluate how the risks of foodborne diseases might change in response to climate change, credible and usable climate information tailored to the specific application question is needed. Global Climate Model (GCM) data generally need to, both, be downscaled to the scales of the application to be usable, and represent, well, the key characteristics that inflict health impacts. This study presents an evaluation of temperature-based heat indices for the Washington D.C. area derived from statistically downscaled GCM simulations for 1971-2000--a necessary step in establishing the credibility of these data. The indices approximate high weekly mean temperatures linked previously to occurrences of Salmonella infections. Due to bias-correction, included in the Asynchronous Regional Regression Model (ARRM) and the Bias Correction Constructed Analogs (BCCA) downscaling methods, the observed 30-year means of the heat indices were reproduced reasonably well. In April and May, however, some of the statistically downscaled data misrepresent the increase in the number of hot days towards the summer months. This study demonstrates the dependence of the outcomes to the selection of downscaled climate data and the potential for misinterpretation of future estimates of Salmonella infections.

Background.  Enterotoxigenic Escherichia coli (ETEC) and non-O157 Shiga toxin-producing E. coli (STEC) are not detected by conventional culture methods. The prevalence of ETEC infections in the United States is unknown, and recognized cases are primarily associated with foreign travel. Gaps remain in our understanding of STEC epidemiology. Methods.  Two sentinel surveillance sites were enrolled: an urban health maintenance organization laboratory (Laboratory A) and a rural hospital laboratory (Laboratory B). Residual sorbitol MacConkey (SMAC) plates from stool cultures performed at Laboratory A (1996-2006) and Laboratory B (2000-2008) were collected. Colony sweeps from SMAC plates were tested for genes encoding STEC toxins stx1 and stx2 (1996-2008) and ETEC heat-labile and heat-stable toxins eltB, estA 1, 2 and 3 (2000-2008) by polymerase chain reaction (PCR)-based assays. Results.  In Laboratory A, a bacterial pathogen was identified in 7.0% of 21 970 specimens. During 1996-2006, Campylobacter was the most common bacterial pathogen (2.7% of cultures), followed by Salmonella (1.2%), Shigella (1.0%), and STEC (0.9%). Among STEC (n = 196), O157 was the most common serogroup (31%). During 2000-2006, ETEC (1.9%) was the second most common bacterial pathogen after Campylobacter (2.6%). In Laboratory B, of 19 293 specimens tested, a bacterial pathogen was identified for 5.5%, including Campylobacter (2.1%), STEC (1.3%), Salmonella (1.0%), and ETEC (0.8%). Among STEC (n = 253), O157 was the leading serogroup (35%). Among ETEC cases, 61% traveled internationally. Conclusions.  Enterotoxigenic E. coli and STEC infections were as common as most other enteric bacterial pathogens, and ETEC may be detected more frequently by culture-independent multiplex PCR diagnostic methods. A high proportion of ETEC cases were domestically acquired.

Background: Escherichia coli O157:H7 (O157) is the Shiga toxin-producing E. coli (STEC) serotype most frequently isolated and most often associated with hemolytic uremic syndrome (HUS) in the United States. Non-O157 STEC serotypes can also cause serious illness, but their impact as pathogens remains undefined. We compared characteristics of non-O157 and O157 STEC infections identified through sentinel surveillance., Methods: Sentinel sites included a metropolitan health maintenance organization laboratory and a hospital laboratory serving a small city and rural area. We received sorbitol-MacConkey agar plates from every stool culture performed at both sites during 2000-2006. Colony sweeps were screened for stx1 and stx2 by polymerase chain reaction. E. coli identity, serotype, and presence of stx1 and/or stx2 were confirmed on individual isolates., Results: Two hundred six STEC isolates were identified: 108 (52%) were non-O157 serotypes, and 98 (48%) were O157. Of non-O157 cases, 54% involved bloody diarrhea, and 8% involved hospitalization. Non-O157 isolates with at least stx2 were not more likely to cause severe illness (bloody diarrhea, hospitalization, or HUS) than were non-O157 isolates with only stx1. O157 cases were more likely than non-O157 cases to involve bloody diarrhea (78% vs 54%; P < .001), hospitalization (34% vs 8%; P < .001 and HUS (7% vs 0%; P = .005). When including only isolates with at least stx2, O157 cases were still more likely to involve bloody diarrhea (78% vs 56%; P = .02) and hospitalization (33% vs 12%; P = .01) than non-O157 cases., Conclusions: Differences in severity among STEC infections could not be explained by stx2, suggesting that additional factors are important in STEC virulence.

Background: The Minnesota Department of Health (MDH) was notified of an outbreak of conjunctivitis in city A with cultures positive for Streptococcus pneumoniae., Methods: MDH staff contacted clinics and schools in city A and city B regarding conjunctivitis cases, reviewed clinical findings of conjunctivitis cases in city A and collected isolates for subtyping., Results: Between September 1 and December 12, 2003, cities A and B reported 735 conjunctivitis cases. Fifty-one percent of the cases were reported from schools, childcare centers and colleges. Adults were more likely to report itching, burning or swelling of the eye(s); children were more likely to report crusty eyes (P < 0.05). Forty-nine percent of conjunctival cultures (71 of 144) were positive for S. pneumoniae. All isolates were nontypeable by serotyping. Pulsed field gel electrophoresis identified 3 clonal groups with 84% of isolates belonging to one clonal group. Multilocus sequence typing revealed that isolates had the same multilocus sequence type as isolates from a 2002 outbreak at a New England college., Conclusions: This outbreak was widespread in the community and conjunctivitis clinical presentation varied by age. The predominant strains in this outbreak were related to a pneumococcal strain implicated in prior conjunctivitis outbreaks, suggesting these strains have a predilection for causing conjunctivitis.

Immunocompetent cells of earthworms (coelomocytes) contain adherent amoebocytes and large eleocytes (chloragocytes); the latter are filled with numerous granules. We have previously shown that eleocytes of several (but not all) earthworm species exhibit strong autofluorescence detectable by fluorescent microscopy and flow cytometry. In the present article, the molecular origin of eleocytes autofluorescence was elucidated in coelomocytes expelled via dorsal pores in the integument of Eisenia fetida subjected to electric shock (1 min at 4.5 V). Spectrofluorometry (excitation and emission spectra and fluorescence lifetime), together with HPLC analysis of coelomocyte suspensions and supernatants, indicated that riboflavin but not FMN (flavin mononucleotide) or FAD (flavin-adenine dinucleotide) is the main fluorophore responsible for eleocyte fluorescence in this species. Additionally, lipofuscins are suspected to participate in this phenomenon.

Patients on hemodialysis (HD) have impaired exercise performance. Carnitine homeostasis is also abnormal in this population. As carnitine is an important cofactor for muscle energy metabolism, exercise performance and skeletal muscle carnitine metabolism were characterized in eight HD patients, and in five age-matched controls. Each patient underwent graded bicycle exercise testing to define maximal performance, and prolonged exercise at 70% of their peak work capacity. Muscle (vastus lateralis) total carnitine content (carnitine plus all acylcarnitines) at rest was lower in HD patients than in controls (2320 +/- 1190 vs. 3800 +/- 940 nmol/g, P less than 0.05). In patients on HD, muscle carnitine content was inversely correlated to time on HD (r = -0.74, P less than 0.05), and positively correlated to peak exercise performance (r = 0.77, P less than 0.05). In patients on HD, 8 +/- 7% of the muscle carnitine pool at rest was short-chain acylcarnitines (similar to the distribution in controls), but 32 +/- 5% of the plasma carnitine pool consisted of short-chain acylcarnitines. With high-intensity exercise in patients on HD, muscle short-chain acylcarnitine content increased from 130 +/- 130 to 1380 +/- 820 nmol/g (P less than 0.01). The change in muscle short-chain acylcarnitine content with exercise was correlated with the increase in muscle lactate content (r = 0.88, P less than 0.01). In summary, patients on HD had a lower muscle total carnitine content than control subjects which was correlated to exercise performance.(ABSTRACT TRUNCATED AT 250 WORDS)

We utilized a kaolin-activated partial thromboplastin time (APTT) using rabbit brain phospholipid, in which the capacity of a fourfold increased "high" phospholipid concentration (PC) to normalize the abnormal "standard" PC-APTT in patients with lupus anticoagulants is assessed. This system was also used to measure factors VIIIC, IX, and XI. The tissue thromboplastin inhibition test (TTI), a prothrombin time system in which the activity of a lupus anticoagulant is unmasked by the use of dilute thromboplastin, was simultaneously evaluated. Test sensitivity was defined by results on 31 consecutive patients with standard PC-APTT inhibitors and no bleeding tendency. Specificity was based on 94 patients with various other coagulopathies, including coagulation factor inhibitors, severe congenital factor deficiencies, hepatic insufficiency, and warfarin and heparin treatment. Twenty-one patients with lupus erythematosus and standard PC-APTT results within normal limits were also tested. Sensitivity of the APTT system was superior to that of the TTI (97% v 58%); high PC normalized clotting time ratios and factor levels. Positive results were common with both assays in the group of 20 heparinized patients. The APTT system had superior specificity in remaining cases; there were no positive tests among 74 patients. The lupus erythematosus group had a significant decrease in the clotting time ratio with high PC, indicating that low-level lupus anticoagulants are quite prevalent in this group. The kaolin clotting time using rabbit brain phospholipid in standard and high concentrations is a simple, sensitive, and specific technique for diagnosis of lupus anticoagulants.

Blood levels of lipids and lipoproteins are prominent among the factors identified as contributing to the development of coronary artery disease. Studies have demonstrated that reduction of low density lipoprotein (LDL) levels lowers the risk of coronary events and retards the progression of atherosclerotic lesions. LDL receptors play a central role in the metabolism of LDL: they maintain cellular cholesterol homeostasis by effects on cholesterol synthesis, modulate the plasma level of lipoproteins by clearing LDL from the circulation and deliver cholesterol to the adrenal glands and gonads for steroid hormone synthesis and to the liver for bile acid synthesis. The 2 major strategies that have been developed so far to lower LDL levels involve the use of bile acid-binding resins, which bind cholesterol in the intestinal lumen, thereby leading to a decrease in intracellular cholesterol, which increases the rate of synthesis of LDL receptors and increases the rate of LDL clearance; and, more recently, the use of inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, the key enzyme in the biosynthesis of cholesterol. Further studies are required to assess whether HMG-CoA reductase inhibitors, used alone or concomitantly with bile acid-binding resins, are safe and effective for long-term use in patients with elevated LDL levels.