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Antibody tests for detecting past infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have many uses for public health decision making, but demand has largely come from individual consumers. This review focuses on the individual relevance of antibody tests: their accuracy in detecting prior infection, what past SARS-CoV-2 infection can currently infer about future immunity or possible medical sequelae, and the potential future importance of antibody tests for vaccine selection and medical screening. Given uncertainty about the antibody tests (quality, accuracy level, positive predictive value) and what those tests might indicate immunologically (durability of antibodies and necessity for protection from reinfection), seropositive test results should not be used to inform individual decision making, and antibody testing should remain a tool of public health at this time. There is high consumer demand for antibody tests to detect past infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but there is a great deal of uncertainty about what a positive test means immunologically. Uneven test accuracy and statistical challenges, especially in areas of low disease prevalence, further complicate use of antibody tests for individual decision making. Antibody tests are important for convalescent plasma donation and may have future utility to identify coronavirus disease 2019 medical sequelae and for vaccine selection and prioritization. At the population level, tests are needed to support serosurveillance studies, to determine the case fatality rate, and to track increases or decreases in incidence and prevalence, but currently they are of limited utility for individuals. [ABSTRACT FROM AUTHOR]

Clinicians face difficulty in when and in what order to position biologics and Janus kinase inhibitors in patients with anti-tumor necrosis factor-alpha (TNF) refractory ulcerative colitis (UC). We aimed to compare the effectiveness and safety of vedolizumab and tofacitinib in anti-TNF-exposed patients with UC in our prospective nationwide Initiative on Crohn and Colitis Registry. Patients with UC who failed anti-TNF treatment and initiated vedolizumab or tofacitinib treatment were identified in the Initiative on Crohn and Colitis Registry in the Netherlands. We selected patients with both clinical as well as biochemical or endoscopic disease activity at initiation of therapy. Patients previously treated with vedolizumab or tofacitinib were excluded. Corticosteroid-free clinical remission (Simple Clinical Colitis Activity Index ≤2), biochemical remission (C-reactive protein ≤5 mg/L or fecal calprotectin ≤250 μg/g), and safety outcomes were compared after 52 weeks of treatment. Inverse propensity score-weighted comparison was used to adjust for confounding and selection bias. Overall, 83 vedolizumab- and 65 tofacitinib-treated patients were included. Propensity score-weighted analysis showed that tofacitinib-treated patients were more likely to achieve corticosteroid-free clinical remission and biochemical remission at weeks 12, 24, and 52 compared with vedolizumab-treated patients (odds ratio [OR], 6.33; 95% confidence interval [CI], 3.81–10.50; P <.01; OR, 3.02; 95% CI, 1.89–4.84; P <.01; and OR, 1.86; 95% CI, 1.15–2.99; P =.01; and OR, 3.27; 95% CI, 1.96–5.45; P <.01; OR, 1.87; 95% CI, 1.14–3.07; P =.01; and OR, 1.81; 95% CI, 1.06–3.09; P =.03, respectively). There was no difference in infection rate or severe adverse events. Tofacitinib was associated with superior effectiveness outcomes compared with vedolizumab in anti-TNF-experienced patients with UC along with comparable safety outcomes. [Display omitted] [ABSTRACT FROM AUTHOR]

A major goal of hemoglobinopathy research is to develop treatments that correct the underlying molecular defects responsible for sickle cell disease and β-thalassemia. One approach to achieving this goal is the pharmacologic induction of fetal hemoglobin (HbF). This strategy is capable of inhibiting the polymerization of sickle hemoglobin and correcting the globin chain imbalance of β-thalassemia. Despite this promise, none of the currently available HbF-inducing agents exhibit the combination of efficacy, safety, and convenience of use that would make them applicable to most patients. The recent success of targeted drug therapies for malignant diseases suggests that this approach could be effective for developing optimal HbF-inducing agents. A first step in applying this approach is the identification of specific molecular targets. However, while >70 HbF-inducing agents have been described, neither molecular mechanisms nor target molecules have been definitively verified for any of these compounds. To help focus investigation in this area, we have reviewed known HbF-inducing agents and their proposed mechanisms of action. We find that in many cases, current models inadequately explain key experimental results. By integrating features of the erythropoietic stress model of HbF induction with data from recent intracellular signaling experiments, we have developed a new model that has the potential to explain several findings that are inconsistent with previous models and to unify most HbF-inducing agents under a common mechanism: cell stress signaling. If correct, this or related models could lead to new opportunities for development of targeted therapies for the β-hemoglobinopathies. [Copyright &y& Elsevier]

Vitamin D deficiency is common in Crohn's disease (CD). High-dose vitamin D had anti-inflammatory effects in preclinical studies and trials of patients with CD. We performed a randomized trial to determine whether high-dose vitamin D prevents postoperative recurrence of CD after ileocolonic resection. Patients with CD after ileocolonic resection with ileocolonic anastomosis were assigned randomly to groups given weekly 25,000 IU oral vitamin D (n = 72) or placebo (n = 71) for 26 weeks, at 17 hospitals in The Netherlands and Belgium, from February 2014 through June 2017. Patients were assessed at baseline and at weeks 2, 6, 12, and 26 for laboratory and clinical parameters, and underwent ileocolonoscopy at 26 weeks. The primary end point was endoscopic recurrence (modified Rutgeerts score, ≥i2b, as assessed by blinded readers) at 26 weeks. Secondary end points included clinical recurrence (Crohn's disease activity index, ≥220), quality of life (measured by the 36-Item Short Form Health Survey, Inflammatory Bowel Disease Questionnaire, and EuroQol, a 5-dimension questionnaire), and outcomes associated with the baseline serum concentration of vitamin D. In the vitamin D group, serum levels of 25-hydroxy vitamin D increased from a median of 42 nmol/L at baseline to 81 nmol/L at week 26 (P <.00001), whereas levels did not change significantly in the placebo group and remained unchanged at 43 nmol/L. In the intention-to-treat analysis, the proportion of patients with endoscopic recurrence at 26 weeks did not differ significantly between the vitamin D vs the placebo group (58% vs 66%; P =.37). The cumulative rate of clinical recurrence did not differ significantly between the groups (18.1% in the vitamin D group vs 18.3% in the placebo group; P =.91). Quality of life improved slightly over time in both groups, but did not differ significantly between groups (P =.07). There were few adverse events in either group. High-dose vitamin D, compared with placebo, did not reduce the incidence of postoperative endoscopic or clinical recurrence of CD in patients who underwent ileocolonic resection with ileocolonic anastomosis. ClinicalTrials.gov no: NCT02010762. [ABSTRACT FROM AUTHOR]

Objective: To determine what patient and embryo characteristics are correlated with the developmental potential of the peri-implantation embryo.Design: Retrospective study.Setting: Research laboratory.Patients: Six hundred fifty-one cryopreserved human blastocysts donated for research with informed patient consent.Interventions: Not applicable.Main Outcome Measures: Blastocyst attachment to fibronectin-coated plates, trophectoderm outgrowth area, epiblast cell number, total cell number, human chorionic gonadotropin secretion.Results: Patients' body mass index, age, follicle-stimulating hormone: luteinizing hormone ratio on menstrual cycle day 3, antral follicle count on menstrual cycle day 3, antimüllerian hormone level on menstrual cycle day 3, and blastocyst morphological grade were correlated with peri-implantation development outcomes. After controlling for good-quality morphological grades, blastocysts from patients of advanced maternal age developed fewer epiblast cells than blastocysts from younger patients.Conclusions: Extended embryo culture during the peri-implantation period mirrors several disparities in fertility treatment outcome that we see clinically, including those from patients with advanced maternal age, high body mass index, and low ovarian reserve and from embryos with lower-quality morphological grades. This model system may be useful by providing an alternative or more sensitive endpoint assessment in studying patient, clinical, or laboratory factors that may influence preimplantation embryo developmental potential. [ABSTRACT FROM AUTHOR]

Ulcerative proctitis (UP) refractory to 5-aminosalicylic acid (5-ASA) suppositories is a challenge to treat, often requiring step up to immunomodulator or biological therapy. Topical tacrolimus is effective and safe in patients with refractory UP. However, it is not clear how tacrolimus suppositories fit into in the treatment algorithm of UP. We performed a randomized controlled, double-blind study at 8 hospitals in the Netherlands and Belgium from 2014 through 2017. Eighty-five patients with refractory UP (65% women) were randomly assigned to groups given once daily tacrolimus suppositories (2 mg; n = 43) or beclomethasone (3 mg; n = 42) for 4 weeks. The primary outcome was clinical response (decrease in Mayo score of 3 or more). Secondary outcomes included clinical remission, endoscopic response and remission, adverse events and quality of life. Outcomes were compared using Fisher's exact test and Mann-Whitney U test. Proportions of patients with clinical responses were 63% in the tacrolimus group and 59% in the beclomethasone group (P =.812); proportions of patients in clinical remission were 46% and 38%, respectively (P =.638). Proportions of patients with an endoscopic response were 68% and 60% in the tacrolimus group and in the beclomethasone group (P =.636); proportions in endoscopic remission rates were 30% and 13%, respectively (P =.092) Median increases in the inflammatory bowel disease questionnaire score were 18.0 in the tacrolimus group and 20.5 in the beclomethasone group (P =.395). Adverse event rates did not differ significantly between groups. In a 4-week randomized controlled trial, tacrolimus and beclomethasone suppositories induce comparable clinical and endoscopic responses in patients with UP refractory to 5-ASA. There were no significant differences in adverse events rates. Tacrolimus and beclomethasone suppositories are therefore each safe and effective treatment options for 5-ASA refractory disease. EUDRACT 2013-001259-11; Netherlands Trial Register NL4205/NTR4416. [ABSTRACT FROM AUTHOR]

Malaria is a pervasive disease that affects millions of lives each year in equatorial regions of the world. During the erythrocytic phase of the parasite life cycle, Plasmodium falciparum invades red blood cells, where it catabolizes hemoglobin and sequesters the released toxic heme as innocuous hemozoin crystals. Artemisinin (ART)-class drugs are activated in vivo by newly released heme, which creates a carboncentered radical that markedly reduces parasite density. Radical damage to parasite lipids and proteins is perceived to be ARTs' dominant mechanism of action. By contrast, quinoline-class antimalarials inhibit the formation of hemozoin and in this way suppress heme detoxification. Here, we combine malaria parasite assays and scanning probe microscopy of growing β-hematin crystals to elucidate an unexpected mechanism employed by two widely administered antimalarials, ART, and artesunate to subdue the erythrocytic phase of the parasite life cycle. We demonstrate that heme-drug adducts, produced after the radical activation of ARTs and largely believed to be benign bystanders, potently kills P. falciparum at low exogenous concentrations. We show that these adducts inhibit β-hematin crystallization and heme detoxification, a pathway which complements the deleterious effect of radicals generated via parent drug activation. Our findings reveal an irreversible mechanism of heme-ART adduct inhibition of heme crystallization, unique among antimalarials and common crystal growth inhibitors, that opens new avenues for evaluating drug dosing regimens and understanding growing resistance of P. falciparum to ART. [ABSTRACT FROM AUTHOR]

Is there a risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral exposure and potential cross-contamination from follicular fluid, culture media and vitrification solution within the IVF laboratory using strict patient screening and safety measures? This was a prospective clinical study. All women undergoing transvaginal oocyte retrieval were required to have a negative SARS-CoV-2 RNA test 3–5 days prior to the procedure. Male partners were not tested. All cases used intracytoplasmic sperm injection (ICSI). The first tube of follicular fluid aspirated during oocyte retrieval, drops of media following removal of the embryos on day 5, and vitrification solution after blastocyst cryopreservation were analysed for SARS-CoV-2 RNA. In total, medium from 61 patients, vitrification solution from 200 patients and follicular fluid from 300 patients was analysed. All samples were negative for SARS-CoV-2 viral RNA. With stringent safety protocols in place, including testing of women and symptom-based screening of men, the presence of SARS-CoV-2 RNA was not detected in follicular fluid, medium or vitrification solution. This work demonstrates the possibility of implementing a rapid laboratory screening assay for SARS-CoV-2 and has implications for safe laboratory operations, including cryostorage recommendations. [ABSTRACT FROM AUTHOR]