Arithmetic Mean Ratio Research Articles

108.29 A geometric mean–arithmetic mean ratio limit

108.29 A geometric mean–arithmetic mean ratio limit

RSS based multistage statistical method for attack detection and localization in IoT networks

Accurate and reliable positioning of nodes is a must for location-based services (LBS) in the Internet of things (IoT) networks. The LBS are ubiquitous and an easy target for non-cryptographic attacks that traditional security methods cannot address. In this work, we detect the Received Signal Strength (RSS) based attacks that affect the localization of smart devices in the IoT networks and report the attack tolerance of popular IoT protocols. A two-tier ratio metric method and Residue Under Curve (RUC) metric method is utilized to detect the malicious node in the IoT protocols. We propose to use a novel Geometric, and Arithmetic Mean (GM–AM) ratio as a feature to detect the RSS attacks where GM follows strictly Schur-Concavity property and AM follows non-strict concavity property. We evaluate the performance of the proposed method on real-world IoT testbeds with Wireless Fidelity (Wi-Fi), Zigbee, Bluetooth Low Energy (BLE), and Long-Range Wide-Area Network (LoRaWAN) protocols using the RSS values of these opportunistic signals. Also, the effect of RSS attacks on the localization for different protocols is investigated, and we report the method that provides the least localization error under these attacks.

A new species abundance distribution model including the hydrological niche differentiation in water-limited ecosystems

The formation and maintenance mechanism of biodiversity is a key research topic in community ecology. Establishing a model that can be used to explain and predict the changes of community biodiversity is of great significance in facilitating the analysis and protection of biodiversity. How hydrological niche differentiation determines species abundance distribution requires further exploration. In this paper, by analyzing the characteristics of evolutionary stability of plant communities, the evolutionary stability theory of community water resource allocation is studied in water-limited environments. The water consumption of an individual biomass growth is used to quantify the hydrological niche of the species. The arithmetic mean and harmonic mean ratio of the hydrological niche of a species in the community as a new diversity index is used to measure community hydrological niche differentiation. A new hydrological niche plant diversity model is established, and the species abundance curve and species area curve, including the community hydrological niche differentiation factor, are obtained. It was discovered that the distribution model of species abundance was close to the Fisher log series distribution, which unifies and expands the classical diversity theories. The quantitative relationship between the hydrological niche and plant diversity is given. It is proposed that the plant diversity of a community is determined by regionally available water resources and changes in the species abundance that are filtered by the local biological and abiotic environment and driven by the full utilization of water resources.

Outcomes of Refractory Cytomegalovirus Infection in the First Year after Allogeneic Hematopoietic Cell Transplantation

Outcomes of refractory (Rf) cytomegalovirus (CMV) infection (CMVi) after hematopoietic cell transplantation (HCT) are poor owing to limited treatment options and treatment related toxicities. Maribavir, an orally bioavailable CMV antiviral, was recently approved for treatment of Rf-CMVi. Real-world studies quantifying the burden of Rf-CMVi prior to maribavir provide a benchmark for evaluating the net value of novel treatments. Here we report the incidence, clinical outcomes, and healthcare resource utilization (HRU) associated with Rf-CMVi in the first year post-HCT in a cohort of CMV-seropositive HCT recipients (R+) who underwent HCT between January 1, 2014, and December 31, 2017, at Memorial Sloan Kettering Cancer Center and were managed exclusively by preemptive therapy. CMVi was defined as CMV viremia treated preemptively. Rf-CMVi was defined as a <1 log10 decrease and CMV viral load >1000 U/mL after ≥14 days of appropriately dosed therapy. Welldays were defined as alive days not hospitalized and off CMV antivirals by 1 year post-HCT. The impact of Rf-CMVi on mortality and HRU was examined in multivariable models. Of the 286 R+ patients, 145 (50.7%) developed CMVi (99 no Rf-CMVi and 46 Rf-CMVi). Compared with the no Rf-CMVi group, the Rf-CMVi group had higher rates of CMV EOD (23.9% versus 10.1%; P=.030), CMV-related mortality (9.5% versus .0%; P=.002), and all-cause mortality (33.3% versus 15.6%; adjusted P=.049). Rf-CMVi was an independent predictor for readmission (adjusted odds ratio [aOR], 3.24; 95% confidence interval [CI], 2.19 to 4.87; P < .0001); CMV-related readmission (aOR, 9.48; 95% CI, 5.83 to 15.80; P < .0001), and decreased well days (adjusted arithmetic mean ratio, .72; 95% CI, .58 to .89; P=.001) in the first year post-HCT. Rf-CMVi is associated with increased mortality and increased HRU at 1 year after HCT. Improved therapies for Rf-CMVi have the potential of improving HCT outcomes and reducing HRU.

High Plasma sTNF-R1 Level Is Related to Loss of Natural HIV Control in Long-Term Elite Controllers.

Human immunodeficiency virus-1 (HIV-1) elite controllers are heterogeneous due to different immunovirological features. We aimed to identify plasma biomarkers associated with loss of spontaneous HIV-1 control in long-term elite controllers (HIV-LTECs). We performed a retrospective study in 60 HIV-LTECs [36 true-LTECs and 24 LTECs losing control (LTECs-LC)]. We selected a plasma sample from true-LTECs (towards the middle of the follow-up period) and two samples from LTECs-LC (one far from the loss of control and another close to loss of control). Plasma biomarkers were evaluated using multiplex immunoassays. The partial least squares-discriminant analysis provided the variable importance in projection (VIP), and the adjusted Generalized Linear Model provided the adjusted arithmetic mean ratio (aAMR). At the moment of the first LTECs-LC samples, the only plasma biomarker with a VIP≥1.5 was sTNF-R1, which showed higher values in LTECs-LC than true-LTECs [aAMR=1.62 (95%CI=1.20-2.19); p=0.001]. After a median of 3.9 (IQR=4.5) years of follow-up from the first sample, we also had access to a second plasma sample from 10 LTECs-LC patients. At the moment of this second LTECs-LC sample, the only plasma biomarker with VIP≥1.5 was also sTNF-R1, which showed higher values in LTECs-LC than true-LTECs [aAMR=1.93 (95%CI=1.41-2.65); p<0.001]. The difference between the first and second samples of LTECs-LC was significant (Δx= 6.58 (95%=0.3; 12.88); p=0.040). In conclusion, high plasma values of sTNF-R1 appear to discriminate HIV-LTECs that lose the natural control of HIV-1, helping to define a specific phenotype that may be useful for the clinical management of these patients.

DBP rs7041 and DHCR7 rs3829251 are Linked to CD4+ Recovery in HIV Patients on Antiretroviral Therapy.

Background: The lack of the recovery of CD4+ T-cells (CD4+ recovery) among immunodeficiency virus (HIV)-infected patients on antiretroviral therapy (ART) is not well known. We aimed to analyze the association between single nucleotide polymorphisms (SNPs) underlying vitamin D metabolism and the CD4+ recovery in naïve HIV-infected patients who started ART with low baseline CD4+. Methods: We conducted a retrospective study in 411 naïve individuals with plasma HIV load >200 copies/mL and CD4+ <200 cells/mm3. During 24 months of follow-up, all patients had plasma HIV load <50 copies/mL. DNA genotyping was performed using the Sequenom MassARRAY platform. The outcome variable was the change in CD4+ during the study. Results: CD4+ recovery was higher in patients carrying DBP rs7041 AA genotype (AA versus CC/AC) and DHCR7 rs3829251 AA genotype (AA versus GG/AG) (p-value < 0.05). DBP rs7041 AA genotype was linked to increase in CD4+ (adjusted arithmetic mean ratio (aAMR) = 1.22; q-value = 0.011), increase in CD4+ ≥P75th [adjusted odds ratio (aOR) = 2.31; q-value = 0.005], slope of CD4+ recovery (aAMR = 1.25; q-value = 0.008), slope of CD4+ recovery ≥ P75th (aOR = 2.55; q-value = 0.005) and achievement of CD4+ ≥500 cells/mm3 (aOR = 1.89; q-value = 0.023). Besides, DHCR7 rs3829251 AA genotype was related to increase in CD4+ (aAMR = 1.43; q-value = 0.031), increase in CD4+ ≥P75th (aOR = 3.92; q-value = 0.030), slope of CD4+ recovery (aAMR = 1.40; q-value = 0.036), slope of CD4+ recovery ≥ P75th (aOR = 3.42; q-value = 0.031) and achievement of CD4+ ≥500 cells/mm3 (aOR = 5.68; q-value = 0.015). Conclusion: In summary, DHCR7 rs3829251 and DBP rs7041 polymorphisms were associated with CD4+ recovery in HIV-infected patients who started cART with low CD4+ T-cell counts.

Count Data in Medical Research: Poisson Regression and Negative Binomial Regression

Count Data in Medical Research: Poisson Regression and Negative Binomial Regression

TRPM5 rs886277 Polymorphism Predicts Hepatic Fibrosis Progression in Non-Cirrhotic HCV-Infected Patients.

Background: TRPM5 (transient receptor potential cation channel subfamily M member 5) rs886277 polymorphism has been related to liver cirrhosis from different etiologies. The present study investigates the association of TRPM5 rs886277 polymorphism with liver fibrosis progression and cirrhosis development in chronic hepatitis C (CHC) patients. Methods: We conducted a retrospective study of 208 non-cirrhotic patients with CHC, who had at least two liver stiffness measurements (LSM) with a separation of 12 months (baseline LSM (LSM1) and the last LSM (LSM2)). Two outcome variables were considered: (1) LSM2/LSM1 ratio; (2) cirrhosis progression (F4; LSM ≥ 12.5 kPa). DNA genotyping was done at the CeGen using a MassARRAY platform. Results: The follow-up time was similar irrespective of the rs886277 genotype (46.4 months in TT genotype, 46.4 months in CT genotype, and 49.2 months in CC genotype; p = 0.649). The highest LSM increases were found in patients with CC genotype compared with TT and CT genotypes (p = 0.044 and p = 0.038, respectively). The cirrhosis progression was higher in patients with CC genotype than TT genotype (p = 0.033). Thus, the rs886277 C allele was associated with higher cirrhosis progression (adjusted odds ratio (aOR) = 2.64; p = 0.014). Moreover, rs886277 CC genotype was also related to higher values of LSM2/LSM1 ratio (adjusted arithmetic mean ratio a(AMR) = 1.31; p = 0.001) and cirrhosis progression (aOR = 4.33; p = 0.027). Conclusions: TRPM5 rs886277 polymorphism was associated with liver fibrosis progression and cirrhosis development among hepatitis C virus (HCV)-infected patients. Specifically, the rs886277 C allele and CC genotype were risk factors for advancing liver fibrosis and cirrhosis compared to the rs886277 T allele and CT/TT genotype, respectively.

CA-125 and CCL2 may indicate inflammation in peritoneal dialysis patients.

Introduction:Progressive structural changes in the peritoneal membrane occur over the course of treatment in peritoneal dialysis (PD), resulting in an increase in cytokines such as CCL2 and structural changes in peritoneal membrane triggering an increase in CA-125 in dialysate, which reflects a probable local inflammatory process, with possible loss of mesothelial cells. Thus, the current study aimed to evaluate the association between plasma and CCL2 and CA-125 dialysate levels in patients undergoing PD.Methods:Cross-sectional study was conducted with 41 patients undergoing PD. The assessments of CA-125 and CCL2 levels were performed using a capture ELISA. Correlations were estimated using Spearman's correlation and the investigation of the association between the explanatory variables (CCL2) and response variable (CA-125) was done for crude ratio of arithmetic means and adjusted utilizing generalized linear models.Results:A moderate positive correlation was observed between the levels of CA-125 and CCL2 in the dialysate (rho = 0.696). A statistically significant association was found between the levels in the CCL2 and CA-125 dialysate (RoM=1.31; CI = 1.20-1.43), which remained after adjustment for age (RoM = 1.31; CI=1.19-1.44) and for time in months of PD (RoM=1.34, CI=1.22-1.48).Conclusion:The association of CA-125 levels with CCL2 in the dialysate may indicate that the local inflammatory process leads to temporary or definitive changes in peritoneal membrane. A better understanding of this pathogenesis could contribute to the discovery of new inflammatory biomarkers.

Mobility Deterioration During Acute Pneumonia Illness Is Associated With Increased Hospital Length of Stay and Health Service Costs: An Observational Study

Purpose: To assess the association of mobility deterioration during community-acquired pneumonia (CAP) illness on length of stay (LOS), readmissions, and institutional costs. Methods: This longitudinal observational study included 347 individuals hospitalized with CAP. All were offered routine early mobilization with a physiotherapist within 24 hours of admission and then daily during hospital stay. The exposure of interest was mobility status at time of clinical stability when compared with the premorbid level. Modelling adjusted for factors such as age, residential status, premorbid mobility level, comorbidities, and pneumonia severity. Results: One hundred forty-one (41%) individuals met the definition of mobility deterioration during the acute illness. The mean (95% confidence interval [CI]) time from achievement of clinical stability to hospital discharge for the groups with and without mobility deterioration was 5.7 (4.2–7.2) and 2.3 (1.4–3.2) days, respectively, with associated higher hospitalization costs (arithmetic mean ratio [95% CI] 1.61 [1.24–2.10]) in the mobility deterioration group. There was no evidence of an association between mobility deterioration and 90-day readmission (odds ratio [95% CI]: 1.34 [0.81–2.24]). Conclusions: Mobility deterioration during acute pneumonia illness has a significant impact on hospital LOS and resource use even in a hospital system that has an early mobility program. Further research is needed to investigate these associations and alternative interventions. Trial registration: ClinicalTrials.gov, Identifier: NCT02835040.

Describing Differences Among Recent Immigrants and Long-Standing Residents Waiting for Long-Term Care: A Population-Based Retrospective Cohort Study

ObjectivesImmigrants often face many unique cultural and logistical challenges in their health care that differ from nonimmigrants. We sought to describe and compare characteristics and the time to placement between recent immigrants and long-standing residents waiting for long-term care (LTC). DesignPopulation-based retrospective cohort study using linked health administrative data. Setting/ParticipantsWe examined all Ontario residents aged 65 years or older who were placed on the LTC waitlist between January 2007 and December 2010. We defined recent immigrants as those granted permanent residency or citizenship status in Canada after 1985; all others were defined as long-standing residents. MethodsThe primary outcome was the number of days on the waitlist before LTC entry, indexed on the incident waitlist record, with a maximum follow-up until December 2012. A generalized estimating equation model was used to identify factors associated with the number of days spent waiting for LTC entry. ResultsWe identified 56,031 individuals on the LTC waitlist, among whom 3.0% were recent immigrants. Compared with long-standing residents, recent immigrants were younger (age ≥80: 66.6% vs. 72.7%), from lower income neighborhoods (bottom 2 brackets: 50.0% vs. 44.0%), and had fewer comorbidities (≥5: 41.6% vs. 36.5%). A larger proportion of caregivers of recent immigrants reported being unable to continue providing care (21.6% vs. 16.7%) and expressed greater feelings of distress (26.9% vs. 20.7%). The median wait time to LTC placement was 165 days for immigrants versus 126 days for long-standing residents. Applying to a cultural/ethnic-specific home [Arithmetic Mean Ratio (AMR) = 1.32, 95% Confidence Interval (CI) 1.11–1.56] and being an immigrant (AMR = 1.22, 95% CI 1.15–1.30) was associated with significantly longer wait times to placement, adjusting for covariates. Conclusions/ImplicationsRecent immigrants vary considerably from long-standing residents, and tend to wait longer to be placed into LTC homes. Future research is necessary to understand how we can reduce wait times to LTC entry for the aging population, with a particular focus on immigrants who are often highly disadvantaged.

IL7RA rs6897932 Polymorphism is Associated with Better CD4+ T-Cell Recovery in HIV Infected Patients Starting Combination Antiretroviral Therapy.

Interleukin-7 receptor subunit alpha (IL7RA) rs6897932 polymorphism IS related to CD4+ recovery after combination antiretroviral therapy (cART), but no studies so far have analyzed its potential impact in patients with very low CD4+ T-cells count. We aimed to analyze the association between IL7RA rs6897932 polymorphism and CD4+ T-cells count restoration in HIV-infected patients starting combination antiretroviral therapy (cART) with CD4+ T-cells count <200 cells/mm3. We performed a retrospective study in 411 patients followed for 24 months with a DNA sample available for genotyping. The change in CD4+ T-cells count during the follow-up was considered as the primary outcome. The rs6897932 polymorphism had a minimum allele frequency (MAF) >20% and was in Hardy–Weinberg equilibrium (p = 0.550). Of 411 patients, 256 carried the CC genotype, while 155 had the CT/TT genotype. The CT/TT genotype was associated with a higher slope of CD4+ T-cells recovery (arithmetic mean ratio; AMR = 1.16; p = 0.016), higher CD4+ T-cells increase (AMR = 1.19; p = 0.004), and higher CD4+ T-cells count at the end of follow-up (AMR = 1.13; p = 0.006). Besides, rs6897932 CT/TT was related to a higher odds of having a value of CD4+ T-cells at the end of follow-up ≥500 CD4+ cells/mm3 (OR = 2.44; p = 0.006). After multiple testing correction (Benjamini–Hochberg), only the increase of ≥ 400 CD4+ cells/mm3 lost statistical significance (p = 0.052). IL7RA rs6897932 CT/TT genotype was related to a better CD4+ T-cells recovery and it could be used to improve the management of HIV-infected patients starting cART with CD4+ T-cells count <200 cells/mm3.

Job Stress and Heart Rate Variability: Findings From the ELSA-Brasil Cohort.

Evidence suggests that exposure to psychosocial stress at work can inhibit vagal tonus, influencing the capacity to respond to environmental stimuli. We investigated whether job strain and low control and high demand at work, as separate measures, are associated with a reduction in heart rate variability (HRV). This is a cross-sectional study with 9658 active workers at the baseline (2008-2010) of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). HRV was estimated using electrocardiographic recordings for 10 minutes, at rest, examining the following indices were used: root mean square of successive difference, standard deviation of normal to normal, percentage of adjacent R-R intervals with a difference lasting more than 50 ms, low frequency (LF), and high frequency. Job strain was defined based on the demand-control model. Independent associations between job strain and HRV indices were verified using generalized linear models and the magnitude of the association was estimated by evaluating the ratios of arithmetic means. Neither the unfavorable demand-control relation nor job demand dimension separately was associated with HRV. However, the increase of one unit in the control dimension was associated with an increment of 2.2% (95% confidence interval = 1.014-1.029) in the LF mean. After adjustments for sociodemographic characteristics, assessment site, health-related behaviors, and depression, this association remained statistically significant (ratio of arithmetic means = 1.008; 95% confidence interval = 1.0002-1.017). Job control was associated with HRV in a large cohort of civil servants. Nevertheless, it is important to emphasize that only the LF index remained associated with low job control. Further studies are needed to develop a greater understanding of the relationship of psychosocial aspects and autonomic balance.

Detection and Forensics against Stealthy Data Falsification in Smart Metering Infrastructure

False power consumption data injected from compromised smart meters in Advanced Metering Infrastructure (AMI) of smart grids is a threat that negatively affects both customers and utilities. In particular, organized and stealthy adversaries can launch various types of data falsification attacks from multiple meters using smart or persistent strategies. In this paper, we propose a real time, two tier attack detection scheme to detect orchestrated data falsification under a sophisticated threat model in decentralized micro-grids. The first detection tier monitors whether the Harmonic to Arithmetic Mean Ratio of aggregated daily power consumption data is outside a normal range known as safe margin. To confirm whether discrepancies in the first detection tier is indeed an attack, the second detection tier monitors the sum of the residuals (difference) between the proposed ratio metric and the safe margin over a frame of multiple days. If the sum of residuals is beyond a standard limit range, the presence of a data falsification attack is confirmed. Both the `safe margins' and the `standard limits' are designed through a `system identification phase', where the signature of proposed metrics under normal conditions are studied using real AMI micro-grid data sets from two different countries over multiple years. Subsequently, we show how the proposed metrics trigger unique signatures under various attacks which aids in attack reconstruction and also limit the impact of persistent attacks. Unlike metrics such as CUSUM or EWMA, the stability of the proposed metrics under normal conditions allows successful real time detection of various stealthy attacks with ultra-low false alarms.

Impact of DARC rs12075 Variants on Liver Fibrosis Progression in Patients with Chronic Hepatitis C: A Retrospective Study.

The Duffy antigen receptor for chemokines (DARC) rs12075 polymorphism regulates leukocyte trafficking and proinflammatory chemokine homeostasis. Hepatitis C virus (HCV)-mediated liver fibrosis is associated with an uncontrolled inflammatory response. In this study, we evaluate the association between the DARC rs12075 polymorphism and liver stiffness progression in HCV-infected patients. We carried out a retrospective cohort study (repeated measures design) in 208 noncirrhotic patients with chronic hepatitis C (CHC) who had at least two liver stiffness measurements (LSM) with a separation of at least 12 months. We used generalized linear models to analyze the association between DARC rs12075 polymorphism and outcome variables. During a follow-up of 46.6 months, the percentage of patients with stages of fibrosis F0/F1 decreased (p < 0.001), while LSM values and the percentage of patients with cirrhosis increased (p < 0.001). This pattern of changes was maintained in each of the groups of patients analyzed according to their rs12075 genotypes (AA or AG/GG). However, the variations in liver stiffness characteristics were lower in patients with the rs12075 AG/GG genotype (AG/GG versus AA). Thereby, in the adjusted analysis, patients with the rs12075 AG/GG genotype had a lower risk of an increased value of LSM2/LSM1 arithmetic mean ratio (AMR = 0.83; p = 0.001) and of an increase in LSM ≥ 5 kPa (odds ratio (OR) = 0.28; p = 0.009). Besides, patients with rs12075 AG/GG had a lower risk of cirrhosis progression (OR = 0.24; p = 0.009). No significant associations were found for an increase in LSM ≥ 10 kPa. We found an association between the DARC rs12075 single nucleotide polymorphism (SNP) and CHC progression. Specifically, patients with the DARC rs12075 AG/GG genotype had a lower risk of liver fibrosis progression and development of cirrhosis.

The Myeloid-Epithelial-Reproductive Tyrosine Kinase (MERTK) rs4374383 Polymorphism Predicts Progression of Liver Fibrosis in Hepatitis C Virus-Infected Patients: A Longitudinal Study.

Background: The myeloid-epithelial-reproductive tyrosine kinase (MERTK) is involved in hepatic steatosis, inflammation, and liver fibrosis. Here we evaluated the association between the MERTK rs4374383 single nucleotide polymorphism (SNP) and liver fibrosis progression in hepatitis C virus (HCV)-infected patients. Methods: We performed a retrospective study (repeated measures design) in 208 patients who had liver stiffness measurement (LSM), which was assessed using transient elastography. No patient had cirrhosis at baseline (LSM ≥ 12.5 kPa). Results: At baseline, 53.8% were male, the median age was 47.1 years, 13.5% reported a high intake of alcohol, 10.1% were prior injection drug users, 85.3% were infected with HCV genotype 1, and 22.6% had previously failed antiviral therapy (pegylated-interferon-alpha/ribavirin). During a median follow-up of 46.6 months, 26 patients developed cirrhosis. The rs4374383 G carriers had a higher risk of increasing LSM (adjusted arithmetic mean ratio (aAMR) = 1.14; p = 0.006) and a higher likelihood of having an increase in LSM greater than 5 kPa (ΔLSM ≥ 5 kPa) (adjusted odds ratio (aOR) = 2.37; p = 0.029), and greater than 7 kPa (ΔLSM ≥ 7 kPa) (aOR = 3.24; p = 0.032), after controlling for confounding. The SNP’s association with cirrhosis progression was close to statistical significance (aOR = 2.18; p = 0.070). Conclusions: MERTK rs4374383 A carriers had a lower risk of liver fibrosis progression than G carriers, supporting the hypothesis that this SNP seems to have a critical role in the pathogenesis of liver disease in HCV-infected patients.

Dysregulation of the Immune System in HIV/HCV-Coinfected Patients According to Liver Stiffness Status.

Background: Advanced cirrhosis is related to alterations in immunity. We aimed to evaluate the levels of peripheral CD4+ T cells (Tregs) and plasma cytokine in patients coinfected with human immunodeficiency virus and hepatitis C virus (HIV/HCV) according to liver fibrosis stages [evaluated as liver stiffness measure (LSM)] and their linear relationship. Methods: We performed a cross-sectional study on 238 HIV/HCV-coinfected patients (119 had <12.5 kPa, 73 had 12.5–25 kPa, and 46 had >25 kPa). Peripheral T-cell subsets were phenotyped by flow cytometry, plasma biomarkers were assessed by multiplex immunoassays, and LSM was assessed by transient elastography. Results: We found HIV/HCV-coinfected patients had higher values of CD4+ Tregs (p < 0.001), memory Tregs (p ≤ 0.001), and plasma cytokine levels [IFN-γ (p ≤ 0.05) and IL-10 (p ≤ 0.01)] compared with healthy donors and HIV-monoinfected patients. In the multivariate analysis, higher LSM values were associated with reduced levels of IL-10 (adjusted arithmetic mean ratio (aAMR) = 0.83; p = 0.019), IL-2 (aAMR = 0.78; p = 0.017), TNF-α (aAMR = 0.67; p < 0.001), and IL-17A (aAMR = 0.75; p = 0.006). When we focus on HIV/HCV-coinfected patients analyzed by LSM strata, patients with ≥25 kPa had lower values of IL-2 (aAMR = 0.66; p = 0.021), TNF-α (aAMR = 0.565; p = 0.003), and IL-17A (aAMR = 0.58; p = 0.003) than patients with <12.5 kPa. Conclusion: HIV/HCV-coinfected patients showed an immunosuppressive profile compared to healthy controls and HIV-monoinfected patients. Additionally, HIV/HCV-coinfected patients with advanced cirrhosis (LSM ≥ 25 kPa) had the lowest plasma values of cytokines related to Th1 (IL-2 and TNF-α) and Th17 (IL-17A) response.

Genetic variants upstream of TNFAIP3 in the 6q23 region are associated with liver disease severity in HIV/HCV-coinfected patients: A cross-sectional study

BackgroundTNFAIP3 is a crucial hepatoprotective factor due to its anti-inflammatory, anti-apoptotic, anti-oxidant and pro-regenerative functions. The aim of this study was to analyze the associations between genetic variants upstream of TNFAIP3 (rs675520, rs9376293 and rs6920220) and liver fibrosis severity and inflammation in HIV/HCV-coinfected patients. MethodsA cross-sectional study was carried out in 215 HIV/HCV-coinfected patients, who underwent a liver biopsy. TNFAIP3 polymorphisms were genotyped using GoldenGate® assay. Outcome variables were: a) liver fibrosis (Metavir score) [fibrosis stage (F0, F1, F2, F3 and F4) and advanced fibrosis and cirrhosis (F ≥ 3 and F4, respectively)]; b) non-invasive indexes [FIB-4, APRI, and their cut-offs (FIB-4 ≥ 3.25 and APRI≥1.5)]; c) inflammation-related biomarkers (leptin, HGF, NGF, sFasL, sFas, MIF, HA, Ang-2, TIMP1, MMP1 and MMP2). ResultsPatients with rs675520 AG/GG genotypes had decreased odds of having cirrhosis (F4) and advanced fibrosis (FIB-4 ≥ 3.25 and APRI≥1.5) [adjusted Odd Ratio (aOR) = 0.30 (p = 0.025), aOR = 0.20 (p = 0.014), and aOR = 0.34 (p = 0.017), respectively] and lower levels of FIB-4 and APRI [adjusted arithmetic mean ratio (aAMR) = 0.76 (p = 0.003) and aAMR = 0.72 (p = 0.006), respectively]. Patients with rs9376293 CT/CC genotypes had decreased odds of APRI≥1.5 [aOR = 0.39 (p = 0.030)] and lower levels of APRI [aAMR = 0.77 (p = 0.018)]. Patients with rs6920220 AG/AA genotypes had higher odds of having FIB-4 ≥ 3.25 [aOR = 3.72 (p = 0.043)]. Moreover, rs675520 AG/GG genotypes, compared to AA genotype, were associated with lower levels of leptin and NGF (p = 0.002 and p = 0.001, respectively) and higher levels of sFas, MIF, TIMP1 and MMP2 (p = 0.004, p = 0.007, p = 0.020 and p = 0.036, respectively). Also, rs9376293 CT/CC genotypes were related to lower leptin levels (p = 0.026) and higher sFas, MIF, TIMP1 and MMP2 levels (p = 0.029, p = 0.040, p = 0.022 and p = 0.024, respectively). ConclusionsGenetic variants upstream of TNFAIP3 were associated with the liver fibrosis severity and inflammation in HIV/HCV-coinfected patients.

Evaluation of the protection against norovirus afforded by E. coli monitoring of shellfish production areas under EU regulations.

EC Regulation 854/2004 requires the classification of bivalve mollusc harvesting areas according to the faecal pollution status of sites. It has been reported that determination of Escherichia coli in bivalve shellfish is a poor predictor of norovirus (NoV) contamination in individual samples. We explore the correlation of shellfish E. coli data with norovirus presence using data from studies across 88 UK sites (1,184 paired samples). We investigate whether current E. coli legislative standards could be refined to reduce NoV infection risk. A significant relationship between E. coli and NoV was found in the winter months (October to February) using data from sites with at least 10 data pairs (51 sites). We found that the ratio of arithmetic means (log10 E. coli to log10 NoV) at these sites ranged from 0.6 to 1.4. The lower ratios (towards 0.6) might typically indicate situations where the contribution from UV disinfected sewage discharges was more significant. Conversely, higher ratios (towards 1.4) might indicate a prevalence of animal sources of pollution; however, this relationship did not always hold true and so further work is required to fully elucidate the factors of relevance. Reducing the current class B maximum (allowed in 10% of samples) from 46,000 E. coli per 100 g (corresponding NoV value of 75750 ± 103) to 18,000 E. coli per 100 g (corresponding NoV value of 29365 ± 69) reduces maximum levels of NoV by a factor of 2.6 to 1; reducing the upper class B limit to 100% compliance with 4,600 E. coli per 100 g (corresponding NoV value of 7403 ± 39) reduces maximum levels of NoV by a factor of 10.2 to 1. We found using the UK filtered winter dataset that a maximum of 200 NoV corresponded to a maximum of 128 ± 7 E. coli per 100 g. A maximum of 1,000 NoV corresponded to a maximum of 631 ± 14 E. coli per 100 g.

The IL7RA rs6897932 polymorphism is associated with progression of liver fibrosis in patients with chronic hepatitis C: Repeated measurements design.

The polymorphisms at the α-chain of the IL-7 receptor (IL7RA) have been related to T-cell homeostasis and development and may contribute to immune system deregulation. In the present study, we analyzed the association between IL7RA polymorphisms and the progression of liver fibrosis in patients infected with HCV. We carried out a retrospective study with a design consisting of repeated measurements in 187 HCV-infected patients, to study the risk prediction of liver fibrosis progression using genetic factors. We genotyped the rs6897932, rs987106 and rs3194051 IL7RA polymorphisms using the Agena Bioscience’s MassARRAY. Transient elastography was used to measure liver stiffness. The used cut-offs were: <7.1 kPa (F0-F1), 7.1–9.4 kPa (F2; significant fibrosis), 9.5-12.4 kPa (F3; advanced fibrosis), and ≥12.5 kPa (F4; cirrhosis). All HCV genotypes were analyzed. The median of follow-up time was 47.9 months. Baseline liver stiffness measurement (LSM) values did not show significant statistical differences for IL7RA genotypes (p>0.05). In univariate analysis, the rs6897932 T allele had a positive relationship with an increase in LSM (arithmetic mean ratio (AMR) = 1.21 (95%CI = 1.08; 1.36); p = 0.001), progression to advanced fibrosis (F≥3) (odds ratio (OR) = 2.51 (95%CI = 1.29; 4.88); p = 0.006) and progression to cirrhosis (F4) (OR = 2.71 (95%CI = 0.94; 5.03); p = 0.069). In multivariable analysis, the rs6897932 T allele was related to a higher increase of LSM values during follow-up (adjusted AMR = 1.27 (95%CI = 1.13; 1.42); p<0.001) and higher odds of progression to advanced fibrosis [adjusted OR = 4.46 (95%CI = 1.87; 10.62); p = 0.001], and progression to cirrhosis [adjusted OR = 3.92 (95%CI = 1.30; 11.77); p = 0.015]. Regarding IL7RA rs987106 and rs3194051 polymorphisms, we did not find significant results except for the relationship between IL7RA rs987106 and the increase in LSM values [adjusted OR = 1.12 (95%CI = 1.02; 1.23); p = 0.015]. The IL7RA rs6897932 polymorphism seems to be related to increased risk of liver fibrosis progression in HCV-infected patients. Thus, the rs6897932 polymorphism could be related to the physiopathology of CHC and might be used to successfully stratify the risk of CHC progression.