High-performance subambient radiative cooling enabled by optically selective and thermally insulating polyethylene aerogel.

Recent progress in passive radiative cooling technologies has substantially improved cooling performance under direct sunlight. Yet, experimental demonstrations of daytime radiative cooling still severely underperform in comparison with the theoretical potential due to considerable solar absorption and poor thermal insulation at the emitter. In this work, we developed polyethylene aerogel (PEA)-a solar-reflecting (92.2% solar weighted reflectance at 6 mm thick), infrared-transparent (79.9% transmittance between 8 and 13 µm at 6 mm thick), and low-thermal-conductivity (k PEA = 28 mW/mK) material that can be integrated with existing emitters to address these challenges. Using an experimental setup that includes the custom-fabricated PEA, we demonstrate a daytime ambient temperature cooling power of 96 W/m2 and passive cooling up to 13°C below ambient temperature around solar noon. This work could greatly improve the performance of existing passive radiative coolers for air conditioning and portable refrigeration applications.

Systematic alphanumeric-coded endoscopy versus chromoendoscopy for the detection of precancerous gastric lesions and early gastric cancer in subjects at average risk for gastric cancer. / Aplicación de la endoscopia sistemática alfanumérica codificada más cromoendoscopia para la detección de lesiones precancerosas gástricas y cáncer gástrico temprano en sujetos con riesgo promedio de cáncer gástrico.

INTRODUCTION AND AIMS: Gastric cancer is one of the main causes of cancer worldwide, but there is currently no global screening strategy for the disease. Endoscopy is the screening method of choice in some Asian countries, but no standardized technique has been recognized. Systematic alphanumeric-coded endoscopy can increase gastric lesion detection. The aim of the present article was to compare the usefulness of systematic alphanumeric-coded endoscopy with conventional endoscopy for the detection of premalignant lesions and early gastric cancer in subjects at average risk for gastric cancer. MATERIALS AND METHODS: A cross-sectional, comparative, prospective, randomized study was conducted on patients at average risk for gastric cancer (40-50 years of age, no history of H. pylori infection, intestinal metaplasia, gastric atrophy, or gastrointestinal surgery). Before undergoing endoscopy, the patients had gastric preparation (200mg of oral acetylcysteine or 50mg of oral dimethicone). Conventional chromoendoscopy was performed with indigo carmine dye for contrast enhancement. RESULTS: Fifty consecutive cases (mean age 44.4 ± 3.34 years, 60% women, BMI 27.6 ± 5.82 kg/m2) were evaluated. Endoscopic imaging quality was satisfactory in all the cases, with no differences between methods (p = 0.817). The detection rate of premalignant lesions and early gastric cancer was 14% (6 cases of intestinal metaplasia and one case of gastric adenocarcinoma). Sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were 100, 95, 80, 100 and 96%, respectively, for systematic alphanumeric-coded endoscopy, and 100, 45, 20, 100, and 52%, respectively, for conventional endoscopy. Lesion detection through systematic alphanumeric-coded endoscopy was superior to that of conventional endoscopy (p = 0.003; OR = 12). CONCLUSION: Both techniques were effective, but systematic alphanumeric-coded endoscopy significantly reduced the false positive rate.

Post-fundoplication symptoms and complications: Diagnostic approach and treatment. / Síntomas y complicaciones posfunduplicatura: abordaje diagnóstico y tratamiento.

Laparoscopic Nissen fundoplication is currently considered the surgical treatment of choice for gastroesophageal reflux disease (GERD) and its long-term effectiveness is above 90%. Adequate patient selection and the experience of the surgeon are among the predictive factors of good clinical response. However, there can be new, persistent, and recurrent symptoms after the antireflux procedure in up to 30% of the cases. There are numerous causes, but in general, they are due to one or more anatomic abnormalities and esophageal and gastric function alterations. When there are persistent symptoms after the surgical procedure, the surgery should be described as "failed". In the case of a patient that initially manifests symptom control, but the symptoms then reappear, the term "dysfunction" could be used. When symptoms worsen, or when symptoms or clinical situations appear that did not exist before the surgery, this should be considered a "complication". Postoperative dysphagia and dyspeptic symptoms are very frequent and require an integrated approach to determine the best possible treatment. This review details the pathophysiologic aspects, diagnostic approach, and treatment of the symptoms and complications after fundoplication for the management of GERD.

Early tissue responses in psoriasis to the antitumour necrosis factor-α biologic etanercept suggest reduced interleukin-17 receptor expression and signalling.

BACKGROUND: Antitumour necrosis factor (anti-TNF)-α therapy has made a significant impact on the treatment of psoriasis. Despite these agents being designed to neutralize TNF-α activity, their mechanism of action in the resolution of psoriasis remains unclear. OBJECTIVES: To understand better the mechanism of action of etanercept by examining very early changes in the lesional skin of patients with psoriasis responding to etanercept. METHODS: Twenty patients with chronic plaque psoriasis were enrolled and received etanercept 50 mg twice weekly. Skin biopsies were obtained before treatment and on days 1, 3, 7 and 14 post-treatment. Skin mRNA expression was analysed by quantitative reverse-transcription polymerase chain reaction and microarray; cytokine and phosphoprotein levels were assessed using multiplexed bead arrays. RESULTS: In etanercept responders, we observed no significant changes in interleukin (IL)-17A, IL-22 or interferon-γ mRNA or protein in the first week of treatment; however, there was a 2·5-fold downregulation of IL-17 receptor C (IL-17RC) mRNA (P < 0·05) after day 1, accompanied by decreased extracellular signal-regulated kinase-1/2 phosphorylation. Transcriptional analysis revealed that genes suppressed by etanercept significantly overlapped with IL-17A-induced genes, and a marked overlap was also observed between the genes suppressed by etanercept and by the anti-IL-17A agent ixekizumab. Finally we show that TNF-α enhances the expression of IL-17RC, and short hairpin RNA inhibition of IL-17R expression abrogates synergistic gene induction by TNF and IL-17A. CONCLUSIONS: These results suggest that the early responses of psoriasis plaques to etanercept may be due to decreased tissue responsiveness to IL-17A due to suppressed IL-17RC expression in keratinocytes, blunting the strong synergy between TNF-α and IL-17, which contributes to the maintenance of psoriasis lesions.

Thermal imaging as a biometrics approach to facial signature authentication.

A new thermal imaging framework with unique feature extraction and similarity measurements for face recognition is presented. The research premise is to design specialized algorithms that would extract vasculature information, create a thermal facial signature and identify the individual. The proposed algorithm is fully integrated and consolidates the critical steps of feature extraction through the use of morphological operators, registration using the Linear Image Registration Tool and matching through unique similarity measures designed for this task. The novel approach at developing a thermal signature template using four images taken at various instants of time ensured that unforeseen changes in the vasculature over time did not affect the biometric matching process as the authentication process relied only on consistent thermal features. Thirteen subjects were used for testing the developed technique on an in-house thermal imaging system. The matching using the similarity measures showed an average accuracy of 88.46% for skeletonized signatures and 90.39% for anisotropically diffused signatures. The highly accurate results obtained in the matching process clearly demonstrate the ability of the thermal infrared system to extend in application to other thermal imaging based systems. Empirical results applying this approach to an existing database of thermal images proves this assertion.

Autoantibodies against galectin-8: their specificity, association with lymphopenia in systemic lupus erythematosus and detection in rheumatoid arthritis and acute inflammation.

The role of autoantibodies in the pathogenesis of systemic lupus erythematosus (SLE) has not been completely defined. From more than a hundred autoantibodies described in SLE, relatively few have been associated with clinical manifestations. The glycan-binding proteins of the galectin family can modulate the immune system. Anti-galectin autoantibodies thus could have functional and/or pathogenic implications in inflammatory processes and autoimmunity. We previously reported function-blocking autoantibodies against galectin-8 (Gal-8) in SLE. Here we tested these autoantibodies against a series of other human galectins and demonstrated their specificity for Gal-8, being detectable in 23% of 78 SLE patients. Remarkably, they associated with lymphopenia (50% of 18 anti-Gal-8-positive versus 18% of 60 anti-Gal-8-negative cases, Fisher's Exact test two-tailed: P < 0.012). Lymphopenia is a common clinical manifestation in SLE, yet of unknown mechanism. In addition, six of eight patients with both lymphopenia and malar rash had anti-Gal-8 in their sera. Occurrence of these autoantibodies was not confined to SLE as we also found them in sera of patients with rheumatoid arthritis (16%) and septicemia (20%). This study thus establishes occurrence of specific anti-Gal-8 autoantibodies in autoimmune rheumatic diseases and in acute inflammation, with an apparent association to a clinical subset in SLE.

Inhibitory effects of sucrose fatty acid esters on survival of Yersinia enterocolitica on eggshell surface and use of blue lake as indicator of bacterial penetration into eggs.

AIMS: To determine the effectiveness of sucrose monolaurate (SML) and sucrose monocaprate (SMC), alone and in combination with ethylenediaminetetraacetic acid (EDTA), propionic acid (PA) or citric acid (CA) in reducing mesophilic aerobic bacteria (MAB) and Yersinia enterocolitica O:9 populations on eggshells and their damage potential on the microstructure of shell cuticle. METHODS AND RESULTS: Uninoculated eggs and eggs submerged in a solution of Y. enterocolitica were immersed in solutions of the various treatments. MAB and Y. enterocolitica counts on the surface of the eggs were carried out before and after treatment. MAB counts decreased less than 2 logs on uninoculated eggshells irrespective of treatment and reductions of 3.2 and 3.0 logs of Y. enterocolitica were obtained with 1000 microg ml(-1) SML plus 0.1% CA or 1000 microg ml(-1) SML plus 600 microg ml(-1) EDTA solutions, respectively. Y. enterocolitica 2/O:9 was recovered from natural microflora. Use of blue lake staining revealed minimal damage to the shells from the washing treatments. CONCLUSIONS: SML and SMC at 1000 microg ml(-1) combined with CA or EDTA could be effective in reducing Y. enterocolitica on eggshells with a minimal risk of later bacterial recontamination. SIGNIFICANCE AND IMPACT OF THE STUDY: Eggs are a recognized vehicle for transmission of Y enterocolitica although a prevalence of only 2.7% was detected in this study. Washing eggs in solutions containing SML or SMC could eliminate Y. enterocolitica contamination of egg shells.

Endoscopic ultrasound-guided celiac plexus neurolysis in patients with unresectable pancreatic cancer.

BACKGROUND: The treatment of pain in patients with pancreatic cancer is a difficult topic for the patients and their physicians. There are different treatment modalities with variable results. Celiac plexus neurolysis (CPN) is a technique with good previous results using fluoroscopy, CT guidance and recently, guided by endoscopic ultrasound (EUS). The aim of this study is to report the experience of EUS guided CPN (EUS CPN) for treatment of abdominal pain in patients with unresectable pancreatic cancer. METHODS: Patients with inoperable pancreatic cancer diagnosed by CT, MRI and/or EUS were included. The measurement of pain was made with a visual analog pain scale applied before and after the procedure. Follow up was made at weeks 2 and 4 after the procedure. The use of morphine before and after EUS CPN was evaluated. Complications related to the procedure were recorded. RESULTS: Eleven patients (five men and six women) underwent to the procedure, the mean age was 59 years (range 43-82). In follow-up at four weeks after the procedure, pain scores were reduced by at least 5 points of visual analog pain scale in 9 (72.2%) patients. At least a fifty percent reduction in pain or more was documented in 7 (63.6%) patients. Five patients substantially reduced their pain medication. No complications were seen in this study. CONCLUSIONS: The EUS NPC is an efficient and safe method for pain treatment in those patients with inoperable pancreatic cancer.

Yersinia-triggered arthritis in IL-12p40-deficient mice: relevant antigens and local expression of Toll-like receptor mRNA.

OBJECTIVES: To study the role of IL-12p40 at the onset of reactive arthritis (ReA) after Yersinia enterocolitica O:3 infection, and analyse relevant microbial antigens and articular expression of Toll-like receptor (TLR) mRNA. METHODS: Wild-type C57BL/6 and IL-12p40-deficient (IL-12p40-/-) mice were orogastrically infected with Y. enterocolitica O:3. Early (day 3) and late (day 21) after infection, the number of bacteria were determined in Peyer's patches (PP), mesenteric lymph nodes (MLN), the spleen, and joints. Histological studies of joints were performed. Collagen-specific and anti-Yersinia antibodies were measured by enzyme-linked immunosorbent assay (ELISA). The presence of Yersinia antigens was studied by dot blot. Induction of articular mRNA of TLR2, TLR4, and tumour necrosis factor (TNF)-alpha was analysed by reverse transcription-polymerase chain reaction (RT-PCR). TNFalpha protein levels were measured by ELISA. RESULTS: At day 3, bacterial recovery in PP, MLN, and spleen was significantly increased in IL-12p40-/- mice. Histopathological changes were observed in IL-12p40-/- mice at day 21 after infection, and correlated with higher antibody response against type II collagen. Although live bacteria could not be isolated at day 21 after infection, articular microbial components, especially from the outer membrane (OM), were detected. Moreover, intra-articular immunoglobulins to Yersinia antigens were significantly higher in IL-12p40-/- mice. Furthermore, mRNA levels for TLR2, TLR4 and TNFalpha, and TNFalpha protein were increased in joints from IL-12p40-/- mice. CONCLUSIONS: We concluded that IL-12p40 influences the resistance against Yersinia-triggered ReA. Bacterial products such as Yersinia OM could contribute to the ReA by induction of articular TLR expression, which results in an inflammatory response in the joint.

Role of TNFRp55 in Yersinia enterocolitica O:3-induced arthritis: triggering bacterial antigens and articular immune response.

OBJECTIVES: The pathogenesis of reactive arthritis (ReA), an aseptic synovitis that follows an extra-articular infection, is incompletely known. We studied the impact of tumour necrosis factor receptor (TNFR) p55 deficiency on the progression to ReA after oral Yersinia enterocolitica O:3 infection, the Yersinia antigens triggering articular inflammation and a possible articular TNFRp55-mediated mechanism that protects against ReA. METHODS: Wild-type C57BL/6 and TNFRp55-/- mice were orogastrically infected with Y. enterocolitica O:3 and monitored for survival and arthritis development. The bacterial load was determined in mesenteric lymph nodes (MLNs), the spleen and joints. Interferon (IFN)-gamma, TNF-alpha and IL-10 mRNA expression in MLN and joints were analysed by reverse transcription-polymerase chain reaction (RT-PCR). Articular antibodies to Yersinia antigens, TNF-alpha protein and nitric oxide (NO) levels were assessed. Acute arthritis was evaluated after joint injection of Yersinia antigens. RESULTS: The survival rate was 60% in TNFRp55-/- mice. They showed impaired bacterial clearance in MLN, the spleen and joints, and excessive mRNA expression of pro-inflammatory cytokines in MLN. Clinical and histological examinations revealed that TNFRp55-/- mice developed severe arthritis. Moreover, augmented articular outer membrane protein (OMP)-specific antibodies and TNF-alpha but impaired NO levels were detected in TNFRp55-/- mice. Synovial inflammatory response was detected by joint OMP injection. CONCLUSIONS: TNFRp55-mediated immune mechanisms prevent ReA development after oral infection with Y. enterocolitica O:3. Yersinia OMPs are the relevant antigens triggering ReA. NO induction through TNFRp55 signalling could have a local antibacterial function to prevent ReA. This study could contribute to ReA-specific therapeutic studies.

Tumor growth parameters of in-vivo human breast carcinoma: a proposed mathematical model for tumor growth kinetics

Many mathematical models have been proposed to study tumor growth parameters in vivo. Nevertheless most of the medical models have given variable results even when experimental conditions are exactly the same. There are multiple factors that are capable of affecting tumor growth that should be taken into account when proposing a mathematical model for tumor growth in vivo. We discuss here own proposed model for tumor growth kinetics utilizing a modified Gompertz function that better responds to the growth characteristic of in [quot ]vivo[quot ] tumors.

Effect of a dietary supplement combination on weight management, adipose tissue, cholesterol and triglycerides in obese children

A dietary supplement combination consisting of vitamins, minerals and fibers was studied to determine its safety and efficacy on weight/fat loss, cholesterol and triglycerides in children between ages 7-13. This open label trial measured total body weight, body fat percentage, waist circumference, total cholesterol, triglycerides before and after 6 weeks of treatment. The study population consisted of 25 mildly to moderate obese, otherwise healthy children of both sexes. After 6 weeks of treatment, the combination supplement had a statistically significant (p < 0.05) weight reducing effect. This weight reduction was associated with a corresponding statistically significant (p < 0.0001l) decrease in body fat percentage. In addition, significant decreases in total cholesterol (p < 0.0001) and triglycerides (p < 0.0001) were obtained, plus reductions in waist measurements. We conclude that the combination supplement studied herein is a safe and effective way to assist children in weight, fat percentage, cholesterol and triglyceride reduction.

Resistance of Yersinia enterocolitica, Escherichia coli O157:H7 and natural microflora against acidic conditions and freezing-thawing in fresh sausages.

The resistance of Yersinia enterocolitica O:9, Escherichia coli O157:H7 and natural microflora against lactic acid (LA), ascorbic acid (AA), and freezing-thawing in noninoculated and inoculated fresh sausages was studied. Samples were stored at -18 degrees C for 28 days and thawed in microwave (MW), at room temperature (RT), in refrigerator (R) and under flowing of tap water (F) on days 7, 14, 21 and 28. Plate Count Agar (PCA), Sorbitol Mac Conkey agar (SMC) and Mac Conkey agar (MC) were used for microbial counts. A maximal reduction of 1.57 log in mesophilic aerobes and no significant changes in total and fecal coliform levels with respect to the initial counts in natural microflora were observed along storage. In inoculated fresh sausages, reductions of 1.37 log on PCA and 2.17 log on SMC were obtained in E. coli O157:H7 populations as compared to the control groups on day 0. Similarly, reductions of 1.69 log on PCA and 2.79 log on MC as compared to the initial level were observed in counts of Y. enterocolitica inoculated samples. Salmonella Anatum, P. aeruginosa, Y. enterocolitica B1A O:7,8-8-8,19 and E. coli non O157:H7 strains were recovered from the natural microflora by enrichment techniques. Thawing in refrigerator was more frequently related to the best reductions of total mesophilic aerobe, E. coli O157:H7 and Y. enterocolitica O:9 counts than the other thawing methods. Reductions of microbial populations observed in LA treated samples were similar to those observed in AA treated samples. Although the acidic and freezing treatments might reduce the microbial levels in natural microflora of fresh sausages, they appeared to be ineffective in the total elimination of high inocula of pathogens like E. coli O157:H7 and Y. enterocolitica O:9.

Effectiveness of chlorine, organic acids and UV treatments in reducing Escherichia coli O157:H7 and Yersinia enterocolitica on apples.

This study assessed the effectiveness of 200 and 500 ppm of chlorine and organic acids (0.5% lactic acid and 0.5% citric acid) in wash solutions, and UV radiation for reducing Escherichia coli O157:H7 and Yersinia enterocolitica on apples contaminated by two different methods. Residual levels of these pathogens after different treatments were compared. On dip inoculated apples, Y. enterocolitica reductions of 2.66 and 2.77 logs were obtained with 200 and 500 ppm chlorine combined with 0.5% lactic acid, respectively. The E. coli O157:H7 population decreased 3.35 log with 0.5% lactic acid wash solution, and 2.72 and 2.62 logs after 500 ppm chlorine and 500 ppm chlorine plus 0.5% lactic acid treatments, respectively. Similar reductions were obtained with UV radiation. On spot inoculated apples, significant (p < 0.05) decreases of 4.67 and 4.58 logs were observed in E. coli O157:H7 and Y. enterocolitica levels, respectively, after 500 ppm chlorine plus 0.5% lactic acid treatment as compared with the control. In sectioned apples, microorganisms infiltrated in inner core region and pulp were not significantly (p < 0.05) affected by disinfection treatments. No pathogens were detected in the natural microflora on apples. Reductions such as those obtained with 500 ppm chlorine plus 0.5% lactic acid solution were very proximal to the 5-log score required by FDA for apple disinfection.

Effect of chlorine, sodium chloride, trisodium phosphate, and ultraviolet radiation on the reduction of Yersinia enterocolitica and mesophilic aerobic bacteria from eggshell surface.

Eggshell sanitizing practices are necessary to improve microbiological safety of fresh hen eggs and their products. In this work, the effects of 100 mg/liter free chlorine (chl), 3% sodium chloride (NaCl), 1, 5, and 12% trisodium phosphate (TSP) in wash solutions, and UVR (ultraviolet radiation; 4.573 microW/cm2) were studied at different times on uninoculated and Yersinia enterocolitica-inoculated eggs. On uninoculated eggs, the best results were obtained with 100 mg/liter chlorine and UV exposure for >25 min, with reductions of 1.28 and 1.60 log cycles, respectively, compared to the average bacterial count (4.55 log CFU/egg) on the control (untreated eggs). On Y. enterocolitica-inoculated eggs, highest reductions of the average bacterial count (7.35 log CFU/egg) were obtained with 5 and 12% TSP and 100 mg/liter chl. The decrease obtained with 12% TSP (3.74-log reduction) was significantly higher (P < 0.05) than those obtained with the remaining treatments. Y. enterocolitica was more resistant to UVR than the eggshell natural mesophilic aerobic microflora, except when low inoculum (4.39 log CFU/egg) was assayed. Changes in eggshell microstructure were measured by the blue lake staining method. The presence of Yersinia and Salmonella in eggshell natural flora was also investigated.

Influenza A among patients with human immunodeficiency virus: an outbreak of infection at a residential facility in New York City.

Although annual influenza vaccination is recommended for persons who are infected with human immunodeficiency virus (HIV), data are limited regarding the epidemiology of influenza or the effectiveness of influenza vaccination in this population. We investigated a 1996 outbreak of infection with influenza A at a residential facility for persons with AIDS. We interviewed 118 residents and employees, reviewed 65 resident medical records, and collected serum samples for measurement of influenza antibody titers. After controlling for history of smoking, influenza vaccination, and resident or employee status, in a multivariate model, HIV infection was not statistically associated with influenza-like illness (ILI). Symptoms and duration of ILI were similar for most HIV-infected and HIV-uninfected persons. However, 8 (21.1%) of 38 HIV-infected persons with ILI (vs. none of 15 HIV-uninfected persons) were either hospitalized, evaluated in an emergency room, or had ILI lasting > or = 14 days (P=.06). Vaccination effectiveness (VE) was similar for HIV-infected and HIV-uninfected persons. Vaccination was most effective among HIV-infected persons with CD4 cell counts of >100 cells/microL (VE, 65%; 95% CI, 36%--81%) or HIV type 1 virus load of <30,000 copies/mL (VE, 52%; 95% CI, 11%--75%). Providers should continue to offer influenza vaccination to HIV-infected persons.

Antibacterial effects of different food-related phosphates using Aeromonas hydrophila.

Aeromonas hydrophila is considered to be an emergent food-related bacterium. Phosphates are used as additives, mainly in meat products, to improve the quality of these foods. The antibacterial properties of phosphates are also well known. In this work, two A. hydrophila strains in early exponential phase were used: (A) A. hydrophila ATCC 7965 and (B) A. hydrophila derived from food, isolated in our laboratory. MIC and MBC studies were performed to assess the antibacterial effects of four phosphates assayed in brain heart infusion broth (BHI) and modified complete defined synthetic medium (mCDS) as compared to cooked ground meat medium (CM). The MBC values of the phosphates in CM were significantly higher than MIC values in BHI broth and mCDS medium (P < 0.05). In the two latter media, the growth of both A. hydrophila strains was totally inhibited by concentrations between 0.5 and 3.0%. Although all the assayed phosphates proved to have bactericidal effects on A. hydrophila, 0.5% sodium acid pyrophosphate (SAPP) exhibited greater effects in both strains and was selected for subsequent experiments. The bacteriolytic effect of SAPP was spectrophotometrically determined (260 nm of absorbance) by means of the leakage of intracellular nucleotides and microscopically confirmed by the presence of massive gelatinous aggregates. These were identified by enzymes (RNase, DNase, and proteinase) that hydrolyzed the nucleotides and proteins released during cellular lysis in the presence of SAPP. It was concluded that 0.5% SAPP can have bactericidal and bacteriolytic effects in early exponential phase A. hydrophila cells.

Survival of Yersinia enterocolitica and mesophilic aerobic bacteria on eggshell after washing with hypochlorite and organic acid solutions.

Populations of Yersinia enterocolitica 0:9 and mesophilic aerobic bacteria on the shell of fresh chicken eggs were assessed prior and after washing with 0.75%, 1%, and 3% acetic and lactic acids, 50, 100, and 200 mg/liter (ppm) of chlorine, and water. Highest reductions of mesophilic aerobic bacterial populations (normal flora) on trypticase soy agar were 1.28 and 2.15 log10 cycles with 100 and 200 mg/liter of chlorine, 0.28 and 0.36 log10 cycles with 1% and 3% acetic acid, and 0.70 and 0.71 log10 cycles with 1% and 3% lactic acid, respectively, as compared to the control group. No Salmonella or Yersinia were detected among the natural flora of the eggs. On Y. enterocolitica O:9-inoculated eggs, reductions of 2.66, 2.77, and 2.92 log10 cycles by 50, 100, and 200 mg/liter of chlorine, of 2.47, 2.48, and 2.49 log10 cycles by 0.75%, 1%, and 3% of acetic acid, and of 2.48 and 2.72 log10 cycles with 1% and 3% of lactic acid, respectively, were observed with respect to the control. Organic acids at 3% caused detachment of the surface cuticle of the eggshell. Y. enterocolitica was more sensitive to the wash treatments than the natural microflora. The absence of potentially pathogenic Y. enterocolitica, observed for other fresh foods, should be a norm for fresh eggs sold in retail stores.

Yersinia enterocolitica O:8 and O:5 lipopolysaccharide arthritogenicity in hamsters.

OBJECTIVE: To assess the arthritogenicity of Yersinia enterocolitica O:8 and O:5 lipopolysaccharide (LPS) administered separately as single antigens in hamsters. METHODS: Male hamsters of the Syria strain were intramuscularly injected into each of the hind paws with two doses of Y. enterocolitica LPS O:8 or O:5. The measurement of swelling using a plethysmometer, the analysis of histological changes by routine techniques and the kinetics of LPS-specific antibodies and autoantibodies evaluated by enzyme-linked immunosorbent assay (ELISA) were performed. RESULTS: LPS O:8 was demonstrated to be more arthritogenic than LPS O:5, inducing acute arthritis on day 3 post-injection as well as more significant and longer lasting joint swelling after a second dose. LPS O:8 caused severe histopathological changes in the joints. Important LPS O:8-specific IgG responses and antibodies against type I and II collagen were observed. CONCLUSION: LPS O:8 administered alone has arthritogenic power and induces activation of autoreactive clones. This study supports the key role of LPS in the development of reactive arthritis.