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GaGeTe is a layered topological semimetal that has been recently found to exist in at least two different polytypes, α-GaGeTe (R3¯m) and β-GaGeTe (P63mc). Here we report a joint experimental and theoretical study of the structural, vibrational, and electronic properties of these two polytypes in high-pressure conditions. Both polytypes show anisotropic compressibility and two phase transitions, above 7 and 15 GPa, respectively, as confirmed by XRD and Raman spectroscopy measurements. Although the nature of the high-pressure phases could not be confirmed, comparison with other chalcogenides and total-energy calculations allow us to propose possible high-pressure phases for both polytypes with an increase in coordination for Ga and Ge atoms from 4 to 6. In particular, the simplification of the X-ray pattern for both polytypes above 15 GPa suggests a transition to a structure of relatively higher symmetry than the original one. This result is consistent with the rocksalt-like high-pressure phases observed in parent III-VI semiconductors, such as GaTe, GaSe, and InSe. Pressure-induced amorphization is observed upon pressure release. The electronic band structures of α-GaGeTe and β-GaGeTe and their pressure dependence also show similarities to III-VI semiconductors, thus suggesting that the germanene-like sublayer induces a semimetallic character in both GaGeTe polytypes. Above 3 GPa, both polytypes lose their topological features, due to the opening of the direct band gap, while the reduction of the interlayer space increases the thermal conductivity at high pressure.

During the period October–November 2017, an outbreak of Legionnaires’ disease involving 27 cases occurred in the tourist area of Palmanova (Mallorca, Spain). The majority of cases were reported by the European Centre of Disease Prevention and Control (ECDC) as travel associated cases of Legionnaires’ disease (TALD). Most cases belonged to different hotel cluster alerts. No cases were reported among the local population residing in the area. All tourist establishments associated with one or more TALD cases were inspected and sampled by public health inspectors. All relevant sources of aerosol emission detected were investigated and sampled. The absence of active cooling towers in the affected area was verified, by documents and on-site. Samples from hot tubs for private use located on the terraces of the penthouse rooms of a hotel in the area were included in the study. Extremely high concentrations (> 106 CFU/l) of Legionella pneumophila, including the outbreak strain, were found in the hot tubs of vacant rooms of this hotel thus identifying the probable source of infection. Meteorological situation may have contributed to the geographical distribution pattern of this outbreak. In conclusion, hot tubs for private use located outdoors should be considered when investigating community outbreaks of Legionnaires’ disease of unclear origin.

Abstract Background Young children with sickle cell anaemia (SCA) often have slowed processing speed associated with reduced brain white matter integrity, low oxygen saturation, and sleep-disordered breathing (SDB), related in part to enlarged adenoids and tonsils. Common treatments for SDB include adenotonsillectomy and nocturnal continuous positive airway pressure (CPAP), but adenotonsillectomy is an invasive surgical procedure, and CPAP is rarely well-tolerated. Further, there is no current consensus on the ability of these treatments to improve cognitive function. Several double-blind, randomised controlled trials (RCTs) have demonstrated the efficacy of montelukast, a safe, well-tolerated anti-inflammatory agent, as a treatment for airway obstruction and reducing adenoid size for children who do not have SCA. However, we do not yet know whether montelukast reduces adenoid size and improves cognition function in young children with SCA. Methods The Study of Montelukast In Children with Sickle Cell Disease (SMILES) is a 12-week multicentre, double-blind, RCT. SMILES aims to recruit 200 paediatric patients with SCA and SDB aged 3–7.99 years to assess the extent to which montelukast can improve cognitive function (i.e. processing speed) and sleep and reduce adenoidal size and white matter damage compared to placebo. Patients will be randomised to either montelukast or placebo for 12 weeks. The primary objective of the SMILES trial is to assess the effect of montelukast on processing speed in young children with SCA. At baseline and post-treatment, we will administer a cognitive evaluation; caregivers will complete questionnaires (e.g. sleep, pain) and measures of demographics. Laboratory values will be obtained from medical records collected as part of standard care. If a family agrees, patients will undergo brain MRIs for adenoid size and other structural and haemodynamic quantitative measures at baseline and post-treatment, and we will obtain overnight oximetry. Discussion Findings from this study will increase our understanding of whether montelukast is an effective treatment for young children with SCA. Using cognitive testing and MRI, the SMILES trial hopes to gain critical knowledge to help develop targeted interventions to improve the outcomes of young children with SCA. Trial registration ClinicalTrials.gov NCT04351698 . Registered on April 17, 2020. European Clinical Trials Database (EudraCT No. 2017-004539-36). Registered on May 19, 2020

GaGeTe is a layered van der Waals material composed of germanene and GaTe sublayers that has been recently predicted to be a basic Z2 topological semimetal. To date, only one polytype of GaGeTe is known with trigonal centrosymmetric structure (α phase, space group R-3m, No. 166). Here we show that as-grown samples of GaGeTe show traces of at least another polytype with hexagonal non-centrosymmetric structure (β phase, space group P63mc, No. 186). Moreover, we suggest that another bulk hexagonal polytype (γ phase, space group P-3m1, No. 164) could also be found near room conditions. Both α and β polytypes have been identified and characterized by means of X-ray diffraction and Raman scattering measurements with the support of ab initio calculations. We provide the vibrational properties of both polytypes and show that the Raman spectrum reported for GaGeTe almost forty years ago and attributed to the α phase, was, in fact, that of the secondary β phase. Additionally, we show that a Fermi resonance occurs in α-GaGeTe under non-resonant excitation conditions, but not under resonant excitation conditions. Theoretical calculations show that bulk β-GaGeTe is a non-centrosymmetric weak topological semimetal with even smaller lattice thermal conductivity than centrosymmetric bulk α-GaGeTe. In perspective, our work paves the way for the control and engineering of GaGeTe polytypes to design and implement complex van der Waals heterostructures formed by a combination of centrosymmetric and non-centrosymmetric layers of up to three different polytypes in a single material, suitable for a number of fundamental studies and technological applications.

Abstract Background Pregnancies in women with sickle cell disease (SCD) are associated with a higher risk of sickle and pregnancy complications. Limited options exist for treating SCD during pregnancy. Serial prophylactic exchange blood transfusion (SPEBT) has been shown to be effective in treating SCD outside pregnancy, but evidence is lacking regarding its use during pregnancy. The aim of this study is to assess the feasibility and acceptability of conducting a future phase 3 randomised controlled trial (RCT) to establish the clinical and cost effectiveness of SPEBT in pregnant women with SCD. Methods The study is an individually randomised, two-arm, feasibility trial with embedded qualitative and health economic studies. Fifty women, 18 years of age and older, with SCD and a singleton pregnancy at ≤ 18 weeks’ gestation will be recruited from six hospitals in England. Randomisation will be conducted using a secure online database and minimised by centre, SCD genotype and maternal age. Women allocated to the intervention arm will receive SPEBT commencing at ≤ 18 weeks’ gestation, performed using automated erythrocytapheresis every 6–10 weeks until the end of pregnancy, aiming to maintain HbS% or combined HbS/HbC% below 30%. Women in the standard care arm will only receive transfusion when clinically indicated. The primary outcome will be the recruitment rate. Additional endpoints include reasons for refusal to participate, attrition rate, protocol adherence, and maternal and neonatal outcomes. Women will be monitored throughout pregnancy to assess maternal, sickle, and foetal complications. Detailed information about adverse events (including hospital admission) and birth outcomes will be extracted from medical records and via interview at 6 weeks postpartum. An embedded qualitative study will consist of interviews with (a) 15–25 trial participants to assess experiences and acceptability, (b) 5–15 women who decline to participate to identify barriers to recruitment and (c) 15–20 clinical staff to explore fidelity and acceptability. A health economic study will inform a future cost effectiveness and cost-utility analysis. Discussion This feasibility study aims to rigorously evaluate SPEBT as a treatment for SCD in pregnancy and its impact on maternal and infant outcomes. Trial registration NIH registry ( www.clinicaltrials.gov ), registration number NCT03975894 (registered 05/06/19); ISRCTN ( www.isrctn.com ), registration number ISRCTN52684446 (retrospectively registered 02/08/19).

ObjectiveThe adalimumab biosimilars FKB327 and GP2017 were approved for the therapy of patients with inflammatory bowel disease (IBD). Relatively few prospective studies with biosimilar adalimumab in patients with IBD have been published. The aim of this prospective observational study was to evaluate the effectiveness and safety of the biosimilar adalimumab.Material and methodsAdalimumab biosimilars FKB327 (Hulio®) and GP2017 (Hyrimoz®) were indicated to 50 naive patients in terms of biological therapy with Crohn's disease (CD) or ulcerative colitis (UC). Effectiveness of therapy was evaluated via the Crohn's Disease Activity Index [CDAI] or the Mayo Scoring System [MSS] in patients with CD or UC, respectively, before and after 12 weeks. Additional goals were to evaluate weight changes, laboratory tests and complications or adverse events of this therapy.ResultsIn CD patients, remission (CDAI ConclusionsThis prospective observational study proved the effectiveness of the adalimumab biosimilars FKB327 and GP2017 in IBD.

Background: Vedolizumab demonstrated different placental pharmacokinetics than other immunoglobulin G1 antibodies, leading to lower drug levels in cord blood in contrast to maternal blood at the time of delivery. The placental transfer of ustekinumab seems to have a pattern similar to anti-tumour necrosis factor agents. Current evidence on the placental pharmacokinetics of vedolizumab and ustekinumab is limited. We aimed to assess the placental transfer of ustekinumab and vedolizumab in pregnant patients with inflammatory bowel disease. Methods: Consecutive women from a prospective observational study who were exposed to ustekinumab or vedolizumab within 2 months prior to conception or during pregnancy were included. Ustekinumab and vedolizumab levels were measured in maternal and cord blood at the time of delivery. Results: Drug levels were available in 31 infant-mother pairs (15 exposed to ustekinumab and 16 to vedolizumab). The median maternal and newborn ustekinumab levels were 5.3 mg/l and 10.3 mg/l, respectively (the median infant-to-maternal ratio was 1.7), while the median maternal and cord vedolizumab levels were 7.3 mg/l and 4.5 mg/l (the median infant-to-maternal ratio was 0.66). The ustekinumab levels in cord blood positively correlated with the maternal levels at delivery (ρ = 0.751, p = 0.001). However, no correlation with the timing of the last drug administration was found. In contrast, the vedolizumab levels in cord blood demonstrated significant positive correlation with the maternal levels (ρ = 0.831, p

HMIP-2 is a human quantitative trait locus affecting peripheral numbers, size and hemoglobin composition of red blood cells, with a marked effect on the persistence of the fetal form of hemoglobin, HbF, in adults. The locus consists of multiple common variants in an enhancer region for MYB (chr 6q23.3), which encodes the hematopoietic transcription factor cMYB. Studying a European population cohort and four African-descended groups of patients with sickle cell anemia, we found that all share a set of two spatially separate HbF-promoting alleles at HMIP-2, termed "A" and "B." These typically occurred together ("A-B") on European chromosomes, but existed on separate homologous chromosomes in Africans. Using haplotype signatures for "A" and "B," we interrogated public population datasets. Haplotypes carrying only "A" or "B" were typical for populations in Sub-Saharan Africa. The "A-B" combination was frequent in European, Asian, and Amerindian populations. Both alleles were infrequent in tropical regions, possibly undergoing negative selection by geographical factors, as has been reported for malaria with other hematological traits. We propose that the ascertainment of worldwide distribution patterns for common, HbF-promoting alleles can aid their further genetic characterization, including the investigation of gene-environment interaction during human migration and adaptation.

Mushrooms are known not only for their taste but also for beneficial effects on health attributed to plethora of constituents. All mushrooms belong to the kingdom of fungi, which also includes yeasts and molds. Each year, hundreds of new metabolites of the main fungal sterol, ergosterol, are isolated from fungal sources. As a rule, further testing is carried out for their biological effects, and many of the isolated compounds exhibit one or another activity. This study aims to review recent literature (mainly over the past 10 years, selected older works are discussed for consistency purposes) on the structures and bioactivities of fungal metabolites of ergosterol. The review is not exhaustive in its coverage of structures found in fungi. Rather, it focuses solely on discussing compounds that have shown some biological activity with potential pharmacological utility.

This current Special Issue of Molecules gathers selected communications on terpenes and terpene derivatives, clearly demonstrating the sustained interest in and importance of natural products in this field; fields connected to secondary metabolites; and renewable resources of plant and animal compounds for medicinal, material, supramolecular, and general chemistry research [...]

Abstract Background Early detection and interventions have enabled patients with sickle cell disease (SCD) to live well into adulthood. Consequently, the chronicity of SCD allows for the insidious manifestation of multisystem complications, including renal damage. Cystic renal lesions are commonly incidentally discovered on ultrasound and computerised tomography (CT) imaging of the abdomen. Most are benign simple cysts, however, difficulties may be encountered if infection, rupture, haemorrhage or cancerous changes develop. We aimed to determine whether patients with SCD have a higher prevalence of simple renal cysts compared to non-SCD individuals. Methods Data for a group of 223 patients with SCD who had undergone an ultrasound and/or CT imaging of the abdomen were extracted for comparison with 180 control patients (haemoglobin genotype unknown), matched for age and ethnicity. Scans were evaluated for 198 SCD patients and 180 controls. Results Renal cysts were found in 58% of the SCD group and 20% of the controls (OR 5.4 (CI 2.6–11.0), RR 2.8 (CI 1.9–4.2)). Bilateral renal cysts were found in 28% of the SCD participants in comparison with 5% of the control group. In those who had one or more cysts identified, the average number of cysts was 3.76 for the SCD group and 1.94 for the controls. Men with SCD were more likely to develop cysts than women (66% vs 53%), as were men without SCD (22% vs 17%). Conclusions Simple renal cysts occur more frequently, are more abundant and develop at a younger age in patients with SCD than ethnically-matched controls. Further study of the mechanism underlying cyst formation may shed light on both sickle cell nephropathy and other cystic renal diseases.

Background Venous thromboembolism (VTE) is a major cause of preventable hospital death, accounting for up to 10% of inpatient mortality. National guidelines recommend that all patients should be regularly assessed for VTE risk, and prescribed mechanical and pharmacological prophylaxis accordingly. While previous studies have focused on improving prescription uptake on admission, there has been relatively little emphasis on the inappropriate suspension of prophylaxis during inpatient stay.Objective The purpose of this project was to identify the reasons and scale of inappropriate suspension of pharmacological VTE prophylaxis for medical inpatients. We subsequently planned to introduce a number of interventions in order to reduce inappropriate suspension.Methods An initial audit of all medical inpatients was carried out to establish the number with inappropriately suspended pharmacological prophylaxis. We then designed a series of educational meetings and electronic prompting interventions to alert prescribers to these errors, followed by re-audit to assess their efficacy.Results The number of patients with inappropriately suspended VTE prophylaxis was significantly reduced following introduction of our intervention strategy.Conclusions Combined education and electronic email prompts are an effective way of alerting practitioners to reduce inappropriate suspension of VTE prophylaxis. With ongoing teaching and integration of prescribing software alerts, this reduction in VTE prescribing errors could be sustained.

The electrochemical behavior of meso-tetrakis(4-sulfonatophenyl) porphyrin tetrasodium salt (TPPS4) was investigated in aqueous media of BR buffer in pH range 2-12. Modern electroanalytical methods, i.e DC tast polarography (DCTP) and differential pulse polarography (both at a dropping mercury electrode), differential pulse voltammetry, adsorptive stripping voltammetry, and cyclic voltammetry (all at a hanging mercury drop electrode) were used for this purpose. TPPS4 gives three cathodic signals for pH 2 - 12, first of them corresponding to a two electron quasireversible process. From these signals, the first two are suitable for the determination of TPPS4 using both polarographic methods with limit of determination about 2·10-6 mol L-1 in BR buffer, pH 10. At concentration higher than 3·10-6 mol L-1, the calibration curve of the first signal deviates from the linear course due to formation of aggregates of TPPS4 in solution. The lowest limit of determination, 5.1·10-7 mol L-1 was achieved by AdSV due to strong adsorption of TPPS4 at the electrode surface. However, for concentrations higher than 1·10-6 mol L-1, the strong adsorption prevents the use of HMDE for voltammetric measurements conducted at low scan rates due to deformation of voltammetric curves and non-linearity of calibration dependences. On the other hand, at higher scan rates used in CV the linear dynamic range for voltammetric determination of TPPS4 is 4·10-7 - 1·10-5 mol L-1.

HbSC disease is the second commonest form of sickle cell disease, with poorly understood pathophysiology and few treatments. We studied the role of K-Cl cotransport activity in determining clinical and laboratory features, and investigated its potential role as a biomarker. Samples were collected from 110 patients with HbSC disease and 41 with sickle cell anemia (HbSS). K-Cl cotransport activity was measured in the oxygenated (K-Cl cotransport100) and deoxygenated (K-Cl cotransport0) states, using radioactive tracer studies. K-Cl cotransport activity was high in HbSC and decreased significantly on deoxygenation. K-Cl cotransport activity correlated significantly and positively with the formation of sickle cells. On multiple regression analysis, K-Cl cotransport increased significantly and independently with increasing reticulocyte count and age. K-Cl cotransport activity was increased in patients who attended hospital with acute pain in 2011 compared to those who did not (K-Cl cotransport100: mean 3.87 versus 3.20, P=0.009, independent samples T-test; K-Cl cotransport0: mean 0.96 versus 0.68, P=0.037). On logistic regression only K-Cl cotransport was associated with hospital attendance. Increased K-Cl cotransport activity was associated with the presence of retinopathy, but this effect was confounded by age. This study links variability in a fundamental aspect of cellular pathology with a clinical outcome, suggesting that K-Cl cotransport is central to the pathology of HbSC disease. Increased K-Cl cotransport activity is associated with increasing age, which may be of pathophysiological significance. Effective inhibition of K-Cl cotransport activity is likely to be of therapeutic benefit.

Patients with sickle cell disease have significant morbidity and mortality. Pulmonary hypertension is suggested to be an important contributor but its nature and severity in these patients and how best to non-invasively assess it are controversial. We hypothesised that a high-output state rather than primary pulmonary vascular pathology may be the major abnormality in sickle cell disease. This study aimed to evaluate the characteristics and severity of pulmonary hypertension in patients with sickle cell disease using detailed echocardiography.We undertook a prospective study in 122 consecutive stable outpatients with sickle cell disease and 30 age, gender and ethnicity-matched healthy controls. Echocardiographic evaluation included 3D ventricular volumes, sphericity, tissue Doppler, and non-invasive estimation of pulmonary vascular resistance. 36% of patients had a tricuspid regurgitant velocity ≥2.5 m.s(-1) but only 2% had elevated pulmonary vascular resistance and the prevalence of right ventricular dysfunction was very low. Patients with raised tricuspid regurgitant velocity had significantly elevated biventricular volumes and globular left ventricular remodelling, related primarily to anaemia. In a subgroup of patients who underwent cardiac catheterization, invasive pulmonary haemodynamics confirmed the echocardiographic findings.Elevated cardiac output and left ventricular volume overload secondary to chronic anaemia may be the dominant factor responsible for abnormal cardiopulmonary haemodynamics in patients with sickle cell disease. 3D echocardiography with non-invasive estimation of pulmonary vascular resistance represents a valuable approach for initial evaluation of cardiopulmonary haemodynamics in sickle cell disease.

Background and Aims Evidence on the safety of newer biologics during pregnancy is limited. We aimed to assess the safety of ustekinumab and vedolizumab treatment during gestation on pregnancy and infant outcome. Furthermore, we evaluated the placental transfer of these agents. Methods We performed a prospective, multicentre, observational study in consecutive women with inflammatory bowel disease exposed to ustekinumab or vedolizumab 2 months prior to conception or during pregnancy. Pregnancy, neonatal, and infant outcomes were evaluated and compared with the anti-tumour necrosis factor [TNF]-exposed control group. Drug levels were assessed in maternal and cord blood at delivery. Results We included 54 and 39 pregnancies exposed to ustekinumab and vedolizumab, respectively. In the ustekinumab group, 43 [79.9%] resulted in live births, and 11 [20.4%] led to spontaneous abortion. Thirty-five [89.7%] pregnancies on vedolizumab ended in a live birth, two [5.1%] in spontaneous, and two [5.1%] in therapeutic abortion. No significant difference in pregnancy outcome between either the vedolizumab or the ustekinumab group and controls was observed [ p  >0.05]. Similarly, there was no negative safety signal in the postnatal outcome of exposed children regarding growth, psychomotor development, and risk of allergy/atopy or infectious complications. The median infant-to-maternal ratio of ustekinumab levels was 1.67 and it was 0.59 in vedolizumab. Conclusions Use of ustekinumab and vedolizumab in pregnancy seems to be safe, with favuorable pregnancy and postnatal infant outcomes. Placental transfer differed between these two drugs, with ustekinumab having similar and vedolizumab having inverse infant-to-maternal ratio of drug levels compared with anti-TNF preparations. [ABSTRACT FROM AUTHOR]

Studies have questioned whether renal dysfunction in sickle cell disease is linked to hemolysis-associated vasculopathy. We have investigated renal function and markers of hemolysis in a cohort of 424 adult African-British patients with sickle cell disease. While significant associations were found in HbSS and HbSβ0 (sickle cell anemia) patients with and without controlling for covariates between hemolytic markers and albuminuria, the associations were not significant in patients with HbSC. Estimated glomerular filtration rate, a marker of renal function, correlated significantly with reticulocyte count and bilirubin. Alpha thalassemia, present in 34% of the sickle cell anaemia patients, had a protective effect against albuminuria in this group. Altogether, the incidence of hyperfiltration was 71% and microalbuminuria 37%, making nephropathy a common complication of sickle cell anemia.