Influence of particle size on the SARS-CoV-2 spike protein detection using IgG-capped gold nanoparticles and dynamic light scattering.

Due to the unprecedented and ongoing nature of the coronavirus outbreak, the development of rapid immunoassays to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its highly contagious variants is an important and challenging task. Here, we report the development of polyclonal antibody-functionalized spherical gold nanoparticle biosensors as well as the influence of the nanoparticle sizes on the immunoassay response to detect the SARS-CoV-2 spike protein by dynamic light scattering. By monitoring the increment in the hydrodynamic diameter (ΔDH) by dynamic light scattering measurements in the antigen-antibody interaction, SARS-CoV-2 S-protein can be detected in only 5 min. The larger the nanoparticles, the larger ΔDH in the presence of spike protein. From adsorption isotherm, the calculated binding constant (K D ) was 83 nM and the estimated limit of detection was 13 ng/mL (30 pM). The biosensor was stable up to 90 days at 4 °C. Therefore, the biosensor developed in this work could be potentially applied as a fast and sensible immunoassay to detect SARS-CoV-2 infection in patient samples.

Beyond the vascular profile: conventional DWI, IVIM and kurtosis in the assessment of hepatocellular carcinoma.

OBJECTIVE: To describe the role of the Diffusion Weighted Imaging (DWI) in the assessment of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Several electronic databases were evaluated in the present review. The search included articles published from January 2010 to May 2019. The references of all articles were also evaluated. All titles and abstracts were assessed, and only the studies of DWI in patients with HCC were retained. RESULTS: HCC is the most common primitive hepatic cancer. The non-invasive radiological criteria for HCC diagnosis are based on the presence of the specific vascular profile characterized by contrast uptake during arterial phase, defined as arterial hyperenhancement, followed by washout in the venous/portal phase. However, arterial hyperenhancement and wash out appearance have a sensitivity rate of 50-60% in lesion smaller than 2 cm. Therefore, other functional parameters have been introduced in the detection and characterization of HCC nodules. DWI has been applied to liver imaging as an excellent tool for detection and characterization of focal liver lesions, increasing clinical confidence and decreasing false positives. The assessment of DW images can be done qualitatively and quantitatively, through the apparent diffusion coefficient (ADC) map. Intravoxel incoherent motion (IVIM) is a more sophisticated analysis, a biexponential model, to better defining the relationship between signal attenuation and increasing b value that separately reproduces tissue diffusivity and tissue perfusion. Traditionally DWI approach to analyze data is founded on the hypothesis that water molecules diffuse within a voxel following a single direction with a Gaussian behavior without any restriction. However, according to the presence of microstructures, water molecules within biologic tissues exhibits a non-Gaussian phenomena proposed by Jensen in 2005 called Diffusion Kurtosis Imaging (DKI). This approach assesses the kurtosis coefficient (K) that shows the deviance of diffusion from a Gaussian approach, and the diffusion coefficient (D) with the correction of non-Gaussian bias. DKI is an advanced DWI model that quantifies non-Gaussian behavior of diffusion and provides both a corrected ADC, as well as the excess kurtosis of tissue, a measure of the extent to which tissue diffusion deviates from a Gaussian pattern. It is believed that the DKI model is more sensitive to tissue microstructural complexity than standard DW. CONCLUSIONS: DWI should be an integral part of study protocol for HCC patients, considering the great advantages due to DWI and DWI-based approaches in detection and characterization of HCC.

A review of LCA assessments of forest-based bioeconomy products and processes under an ecosystem services perspective.

The emergence of politically driven bioeconomy strategies worldwide calls for considering the ecological issues associated with bio-based products. Traditionally, life cycle analysis (LCA) approaches are key tools used to assess impacts through product life cycles, but they present limitations regarding the accounting of multiple ecosystem service-related issues, at both the land-use and supply chain levels. Based on a systematic review of empirical articles, this study provides insights on using LCA assessments to account for ecosystem service-related impacts in the context of bioeconomy activities. We address the following research questions: what is the state of the art of the literature performing LCA assessments of forest-based bioeconomy activities, including the temporal distribution, the geographic areas and products/processes at study, and the approaches and methods used? 2. Which impacts and related midpoints are considered by the reviewed studies and what types of ecosystem service- related information do they bear? Out of over 600 articles found through the Scopus search, 155 were deemed relevant for the review. The literature focuses on North-America and Europe. Most of the articles assessed the environmental impact of lower-value biomass uses. Climate change was assessed in over 90% of the studies, while issues related to ozone, eutrophication, human toxicity, resource depletion, acidification, and environmental toxicity were assessed in 40% to 60% of the studies. While the impact categories accounted for in the reviewed LCA studies bear information relevant to certain provisioning and regulating services, several ecosystem services (especially cultural ones) remain unaccounted for. The implications of our study are relevant for professionals working in the ecosystem services, circular bioeconomy, and/or LCA communities.

The GBA p.Trp378Gly mutation is a probable French-Canadian founder mutation causing Gaucher disease and synucleinopathies.

Biallelic GBA mutations cause Gaucher disease (GD), and heterozygous carriers are at risk for synucleinopathies. No founder GBA mutations in French-Canadians are known. GBA was fully sequenced using targeted next generation and Sanger sequencing in French-Canadian Parkinson disease (PD) patients (n = 436), rapid eye movement (REM)-sleep behavior disorder (RBD) patients (n = 189) and controls (n = 891). Haplotype, identity-by-descent (IBD) and principal component analyses (PCA) were performed using single nucleotide polymorphism-chip data. Data on GD patients from Toronto and Montreal were collected from patients' files. A GBA p.Trp378Gly mutation was identified in two RBD and four PD patients (1% of all patients combined), and not in controls. The two RBD patients had converted to DLB within 3 years of their diagnosis. Haplotype, IBD and PCA analysis demonstrated that this mutation is from a single founder. Out of 167 GD patients screened, 15 (9.0%) carried the p.Trp378Gly mutation, all in trans with p.Asn370Ser. Three (20%) of the GD patients with the p.Trp378Gly mutation had developed Parkinsonism, and 11 patients had family history of PD. The p.Trp378Gly mutation is the first French-Canadian founder GBA mutation to be described, which leads to synucleinopathies and to GD type 1 when in compound heterozygosity with p.Asn370Ser.

EFhd2/Swiprosin-1 is a common genetic determinator for sensation-seeking/low anxiety and alcohol addiction.

In many societies, the majority of adults regularly consume alcohol. However, only a small proportion develops alcohol addiction. Individuals at risk often show a high sensation-seeking/low-anxiety behavioural phenotype. Here we asked which role EF hand domain containing 2 (EFhd2; Swiprosin-1) plays in the control of alcohol addiction-associated behaviours. EFhd2 knockout (KO) mice drink more alcohol than controls and spontaneously escalate their consumption. This coincided with a sensation-seeking and low-anxiety phenotype. A reversal of the behavioural phenotype with ß-carboline, an anxiogenic inverse benzodiazepine receptor agonist, normalized alcohol preference in EFhd2 KO mice, demonstrating an EFhd2-driven relationship between personality traits and alcohol preference. These findings were confirmed in a human sample where we observed a positive association of the EFhd2 single-nucleotide polymorphism rs112146896 with lifetime drinking and a negative association with anxiety in healthy adolescents. The lack of EFhd2 reduced extracellular dopamine levels in the brain, but enhanced responses to alcohol. In confirmation, gene expression analysis revealed reduced tyrosine hydroxylase expression and the regulation of genes involved in cortex development, Eomes and Pax6, in EFhd2 KO cortices. These findings were corroborated in Xenopus tadpoles by EFhd2 knockdown. Magnetic resonance imaging (MRI) in mice showed that a lack of EFhd2 reduces cortical volume in adults. Moreover, human MRI confirmed the negative association between lifetime alcohol drinking and superior frontal gyrus volume. We propose that EFhd2 is a conserved resilience factor against alcohol consumption and its escalation, working through Pax6/Eomes. Reduced EFhd2 function induces high-risk personality traits of sensation-seeking/low anxiety associated with enhanced alcohol consumption, which may be related to cortex function.

Efficacy of ixekizumab compared to etanercept and placebo in patients with moderate-to-severe plaque psoriasis and non-pustular palmoplantar involvement: results from three phase 3 trials (UNCOVER-1, UNCOVER-2 and UNCOVER-3).

BACKGROUND: Palmoplantar psoriasis has significant physical and emotional impact on patients and can be difficult to treat. OBJECTIVE: To evaluate the efficacy of ixekizumab in the treatment of patients with moderate-to-severe plaque psoriasis and moderate-to-severe non-pustular palmoplantar involvement. METHODS: In three phase 3, double-blind, placebo-controlled trials, patients with moderate-to-severe non-pustular plaque psoriasis [UNCOVER-1 (N = 1296), UNCOVER-2 (N = 1224), UNCOVER-3 (N = 1346)] were randomized to subcutaneous 80 mg ixekizumab every 2 or 4 weeks (Q2W, Q4W), after a 160-mg starting dose, or placebo through week 12. Additional UNCOVER-2 and UNCOVER-3 cohorts were randomized to 50 mg etanercept biweekly. Patients entering the open-label long-term extension (UNCOVER-3) received ixekizumab Q4W weeks 12-60. Moderate-to-severe palmoplantar involvement was defined as Palmoplantar Psoriasis Area and Severity Index (PPASI) ≥8. RESULTS: Twenty-eight percent of UNCOVER-1, UNCOVER-2 and UNCOVER-3 patients had baseline palmoplantar involvement (PPASI ≥0, n = 1092) and 9.1% (n = 350) had moderate-to-severe involvement, with mean baseline PPASI ~20, PASI ~24, and most (>60%) had static Physician's Global Assessment ≥4. Higher percentages of patients treated with ixekizumab vs. placebo or etanercept achieved PPASI 50 (approximately 80% vs. 32.9%, 67.8%; ixekizumab, placebo, etanercept, respectively) and PPASI 75 (approximately 70% vs. 18.8%, 44.1%; ixekizumab, placebo, etanercept, respectively) at week 12 (all P < 0.05). PPASI 100 was achieved by higher percentages of ixekizumab-treated patients vs. placebo (approximately 50% vs. 8.2%, P < 0.001) and ixekizumab Q2W-treated patients vs. etanercept (51.8% vs. 32.2%, P < 0.05). Outcomes were maintained or improved in patients continuing on ixekizumab Q4W through week 60. Differences between ixekizumab and placebo or etanercept were statistically significant as early as week 1. CONCLUSION: In a subpopulation analysis of patients from phase 3 trials with moderate-to-severe non-pustular palmoplantar involvement and moderate-to-severe plaque psoriasis, ixekizumab treatment resulted in greater and more rapid improvements than placebo and etanercept at week 12; improvements were sustained with continued treatment.

The relationship between anti-idursulfase antibody status and safety and efficacy outcomes in attenuated mucopolysaccharidosis II patients aged 5 years and older treated with intravenous idursulfase.

In the pivotal phase II/III trial of idursulfase administered intravenously to treat mucopolysaccharidosis II, approximately half of the patients developed antibodies to idursulfase. This post-hoc analysis of data from the phase II/III trial and extension study examined the relationship between antibody status and outcomes. A total of 63 treatment-naïve patients received 0.5 mg/kg of intravenous idursulfase weekly for two years. Thirty-two patients (51%) were positive for anti-idursulfase IgG antibodies, 23 of whom (37%) became persistently positive. All patients who developed an antibody response did so by their scheduled Week 27 study visit. Positive antibody status appeared to have no statistically significant effect upon changes in six-minute walk test distance, percent predicted forced vital capacity, or liver and spleen volume. All patients showed significant decreases in urinary GAG levels, although the antibody positive group maintained somewhat higher urinary GAG levels than their antibody-negative counterparts at the end of study (138.7 vs. 94.7 µg/mg creatinine, p = 0.001). Antibody positivity was not associated with a higher event rate for serious adverse events. Among patients who had no prior infusion-related reactions, antibody positive patients were 2.3 times more likely to have a first infusion-related reaction than those who would remain negative (p = 0.017); the risk increased to 2.5 times more likely for those who were persistently positive (p = 0.009). These differences in risk disappeared among patients with a previous infusion-related reaction, likely because of preventive measures. A genotype analysis for the 36 patients with available data found that patients with nonsense or frameshift mutations may be more likely to develop antibodies, to experience infusion-related reactions, and to have a reduced uGAG response than those with missense mutations, suggesting the possibility that antibodies are not a driver of clinical outcomes but rather a marker for genotype.

Total hip replacement in Gaucher's disease: effects of enzyme replacement therapy.

Total hip replacement in patients with Gaucher's disease with symptomatic osteonecrosis of the femoral head is controversial because of the high early failure rates. We describe four patients who had an uncemented total hip replacement following enzyme replacement therapy for a median of two years and one month (1 to 9.8 years) prior to surgery, and who remained on treatment. At operation, the bone had a normal appearance and consistency. Histopathological examination showed that, compared with previous biopsies of untreated Gaucher's disease, the Gaucher cell infiltrate had decreased progressively with therapy, being replaced by normal adipose tissue. The surfaces of viable bone beyond the osteonecrotic areas showed osteoblasts, indicating remodelling. In one case acetabular revision was carried out after 11 years and eight months. The three remaining patients had a mean follow-up of six years and four months (3.3 to 12 years). We recommend initiating enzyme replacement therapy at least one to two years prior to total hip replacement to facilitate bone remodelling and to allow implantation of uncemented components in these young patients.

Echocardiographic, electrocardiographic and blood pressure changes induced by icodextrin solution in diabetic patients on peritoneal dialysis.

The use of icodextrin as an osmotic agent in solutions for peritoneal dialysis (PD) has important cardiovascular effects related with better control of extracellular volume. Among them, reduction of arterial pressure and an improvement in echocardiographic parameters stand out. In diabetic patients, icodextrin has additional potential advantages related with better metabolic control. In a multicenter, open-label randomized controlled trial, the effects of icodextrin solutions were compared to glucose solutions on echocardiographic, electrocardiographic, and blood pressure changes in diabetic patients on PD. Two phases were noted in the follow-up. In the early phase (6 months), reduction in ambulatory blood pressure (ABP) and left ventricular end diastolic diameter were found in the icodextrin group. These changes correlated with changes in body fluids. In the late phase (12 months), a trend towards baseline values in ABP was seen. Changes in inferior vena cava diameter and in low frequency R-R variability spectral analysis in the icodextrin group suggest that icodextrin increases circulating blood volume and sympathetic tone, probably by accumulation of icodextrin metabolites in the bloodstream and improvement in diabetic neuropathy as a result of lower peritoneal glucose absorption. The effects of icodextrin in diabetic patients were related to better fluid management and metabolic control.

Clinical outcomes and peritoneal histology in patients starting peritoneal dialysis are related to diabetic status and serum albumin levels.

Peritoneal morphological changes seem to be related to dialysis solutions bioincompatibility and to infections, but the uremic milieu per se may also contribute to peritoneal changes. The influence of diabetes and diabetes-associated comorbidities on peritoneal histological changes in the pre-dialysis stage have been insufficiently studied. The aim of this study is to analyze the effect of diabetes and serum albumin levels on peritoneal histology and certain clinical variables such as peritoneal permeability, technique failure, and general mortality in patients starting peritoneal dialysis (PD) treatment. Eighteen PD patients without diabetes (uremic non-diabetic group, U-ND) and 65 with diabetes (uremic diabetic group, U-D) were studied prospectively. Clinical and biochemical variables were registered, and a parietal peritoneum biopsy was obtained at the time of the peritoneal catheter placement. Peritoneal histology was evaluated by light microscopy and immunohistochemistry. A control group of 15 non-uremic, non-diabetic (NU-ND) patients who underwent non-complicated elective abdominal surgery was also studied and used as control. The proportion of patients with peritoneal morphological changes as evaluated by light microscopy was higher in the two groups of uremic patients than in the control. The U-D group had higher mesothelial loss (40.9 vs 29.4%), higher mesothelial basement membrane thickening (45.5 vs 23.5%), higher proportion of vascular wall thickening/sclerosis (39.7 vs 11.1%), and higher proportion of inflammatory infiltrate (45.4 vs 23.6%) than the U-ND group. Uremic patients had lower density of mesothelial cells and higher density of inflammatory cells than the control, as evaluated by immunohistochemistry. These changes were even more striking in the U-D group than in the U-ND group. On the other hand, inflammatory infiltration to the peritoneum, mesothelial cell loss, and mesothelial basement membrane thickening were associated with higher technique failure and mortality. However, when the serum albumin level was introduced into the model, the aforementioned associations became nonsignificant. In conclusion, uremia and diabetes were associated with important peritoneal histological changes before starting PD treatment. Diabetes associated with uremia was more strongly related to the peritoneal changes than uremia per se. Hypoalbuminemia and peritoneal inflammatory infiltrate were markedly associated with technique failure and mortality in patients starting PD treatment.

Micronucleus frequency in human umbilical cord lymphocytes.

The human fetus is exposed to a variety of environmental agents and drugs which cross the placenta and can induce DNA damage. Micronucleus (MN) determination is a suitable and sensitive method for measuring DNA damage and since umbilical cord blood is obtained without any risk for the newborn, we measured the frequency of MN in cells from cord blood in four groups of healthy newborns (NB): 35 NB whose mothers lived in two urban cities (groups I and II); 16 NB from an agricultural area (group III); and 15 NB of mothers with high-risk pregnancy (group IV). MN were also evaluated in the mothers of NB from group I (n=17) and group III (n=14). Acetylcholinesterase (AChE) concentration was measured in groups I and III. The average frequency of binucleated cells with MN was 3.7+/-1.4 in 1000 cells in mothers and 1+/-0.9 in 1000 cells in NB from urban areas; and 4.5+/-2.4 in 1000 cells in mothers and 2+/-1.5 in 1000 cells in NB from the agricultural area. The correlation between the frequency of MN in mothers and NB was significant (r=0.61, p<0.01). AChE levels of samples obtained both from group III mothers and from newborns were similar to those of group I. The Wilcoxon's rank-sum test was applied to measure differences in MN frequency; NB of group I were used as control group. A significant (p<0.01) higher frequency of MN (4+/-2) was found only in lymphocytes from NB from high-risk pregnancies. Data indicate that MN evaluation in umbilical cord samples might be useful in the identification of transplacental mutagens.

Correlation between serum leptin levels and insulin sensitivity in diffuse toxic goiter.

OBJECTIVE: The aim of this survey was to assess the correlation between leptin and insulin sensitivity (IS) in cases of diffuse toxic goiter. DESIGN, PATIENTS, MEASUREMENTS: This is a descriptive study on patients with diffuse toxic goiter (DTG) assessing their body mass index (BMI), serum leptin concentrations, circulating insulin (area under the curve (AuC) of insulin), average insulin level, thyroid hormones, thyroid stimulating hormone (TSH), glycemia and IS (using a hyperinsulinemic-euglycemic clamp and the homeostasis model for assessment of insulin resistance (HOMA-IR) before and after euthyroidism induced with metimazol. RESULTS: The average patient age was 35 years old (range 31-40 years), height was 157 cm (range 151-160 cm), glycemia was 4.3 +/- 0.3 mmol/L and TSH 0.1 +/- 0.1 microU/mL. Average leptin level was 11.3 +/- 2.8 ng/dL, the average insulin level was 10.13 +/- 3.7 mIU/mL and the AuC for insulin was 50.6 +/- 18 microIU x min/mL. No correlation was found between leptin and BMI, thyroid hormones and glycemia. While controlling for the BMI effect, a correlation was found between leptin and TSH (r = -0.77, p = 0.042), as well as between leptin and insulinemia (r = 0.93, r2 = 0.86, p = 0.001) independently from the state of thyroid function. There was a tendency for a high correlation between leptin and the insulin AuC (hyperthyroidism: r = 0.89, p = 0.056; euthyroidism: r = 0.99, p = 0.056). A negative correlation was found between IS and the insulin AuC (rho = -0.58, p = 0.18). There was a high tendency for correlation between leptin and IS when the BMI effect (HOMA-IR: r = 0.70, p = 0.12; PHE: r = -0.55, p = 0.26) was taken into consideration. CONCLUSIONS: There is a high tendency for a negative correlation between leptin and IS when the BMI effect is controlled. There is a high tendency for a positive correlation between leptin and insulin and TSH.

Gaucher disease: variability in phenotype among siblings.

Although many mutations of the GBA gene have been described as causing Gaucher disease, there is generally poor correlation between genotype and phenotype, with a few exceptions. However, most previous reports of genotype-phenotype correlation have involved unrelated individuals, who, even if they share the same mutations, are not as genetically close as siblings. We have studied 24 groups (mostly pairs) of Canadian siblings with type I (non-neuronopathic) Gaucher disease. Since most Canadian provinces have adopted similar criteria for instituting enzyme replacement therapy (ERT), the age at which ERT is begun can serve as a rough surrogate for disease severity, and concordance (or lack of concordance) can be examined between siblings. In 14 of the 24 sibling families, there was sibling concordance: either both siblings were not on ERT, or both were on ERT and had begun at roughly the same age. In these families, there was also much similarity in the clinical features of the disease between siblings. In the other 10 families there was lack of sibling concordance, with only one sibling receiving ERT (or, in one family with three affected siblings, two of three on ERT). In these families, there was also much discrepancy between siblings in the clinical features (as might be expected in a setting where the guidelines for starting ERT are relatively uniform). Possible reasons for the discordances between siblings include macro-environmental and microenvironmental differences. The latter may include micro-environments at the level of the cell (e.g. lysosomal pH, alternative substrates) or at the level of the chromosome (contiguous genes, modifier genes, neutral polymorphisms in GBA).