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1.
Trends Biochem Sci ; 48(1): 11-25, 2023 01.
Article in English | MEDLINE | ID: mdl-35798615

ABSTRACT

The nucleosome-remodeling and deacetylase (NuRD) complex is an essential transcriptional regulator in all complex animals. All seven core subunits of the complex exist as multiple paralogs, raising the question of whether the complex might utilize paralog switching to achieve cell type-specific functions. We examine the evidence for this idea, making use of published quantitative proteomic data to dissect NuRD composition in 20 different tissues, as well as a large-scale CRISPR knockout screen carried out in >1000 human cancer cell lines. These data, together with recent reports, provide strong support for the idea that distinct permutations of the NuRD complex with tailored functions might regulate tissue-specific gene expression programs.


Subject(s)
Nucleosomes , Proteomics , Animals , Humans , Mi-2 Nucleosome Remodeling and Deacetylase Complex/genetics , Cell Line
2.
Biochem Soc Trans ; 2024 Sep 02.
Article in English | MEDLINE | ID: mdl-39221830

ABSTRACT

Chromatin remodelling enzymes reposition nucleosomes throughout the genome to regulate the rate of transcription and other processes. These enzymes have been studied intensively since the 1990s, and yet the mechanism by which they operate has only very recently come into focus, following advances in cryoelectron microscopy and single-molecule biophysics. CHD4 is an essential and ubiquitous chromatin remodelling enzyme that until recently has received less attention than remodellers such as Snf2 and CHD1. Here we review what recent work in the field has taught us about how CHD4 reshapes the genome. Cryoelectron microscopy and single-molecule studies demonstrate that CHD4 shares a central remodelling mechanism with most other chromatin remodellers. At the same time, differences between CHD4 and other chromatin remodellers result from the actions of auxiliary domains that regulate remodeller activity by for example: (1) making differential interactions with nucleosomal epitopes such as the acidic patch and the N-terminal tail of histone H4, and (2) inducing the formation of distinct multi-protein remodelling complexes (e.g. NuRD vs ChAHP). Thus, although we have learned much about remodeller activity, there is still clearly much more waiting to be revealed.

3.
Neurobiol Learn Mem ; 213: 107944, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38825163

ABSTRACT

Persistent substance use despite negative consequences is a key facet of substance use disorder. The last decade has seen the preclinical field adopt the use of punishment to model adverse consequences associated with substance use. This has largely involved the pairing of drug use with either electric foot shock or quinine, a bitter tastant. Whilst at face value, these punishers may model aspects of the physical and psychological consequences of substance use, such models are yet to assist the development of approved medications for treatment. This review discusses progress made with animal models of punishment to understand the behavioral consequences of persistent substance use despite negative consequences. We highlight the importance of examining sex differences, especially when the behavioral response to punishment changes following drug exposure. Finally, we critique the translational value these models provide for the substance use disorder field.


Subject(s)
Sex Characteristics , Substance-Related Disorders , Animals , Substance-Related Disorders/psychology , Humans , Punishment , Disease Models, Animal , Female , Male
4.
Nature ; 558(7709): 233-241, 2018 06.
Article in English | MEDLINE | ID: mdl-29899481

ABSTRACT

We present two narratives on the future of Antarctica and the Southern Ocean, from the perspective of an observer looking back from 2070. In the first scenario, greenhouse gas emissions remained unchecked, the climate continued to warm, and the policy response was ineffective; this had large ramifications in Antarctica and the Southern Ocean, with worldwide impacts. In the second scenario, ambitious action was taken to limit greenhouse gas emissions and to establish policies that reduced anthropogenic pressure on the environment, slowing the rate of change in Antarctica. Choices made in the next decade will determine what trajectory is realized.


Subject(s)
Global Warming/prevention & control , Global Warming/statistics & numerical data , Animals , Antarctic Regions , Atmosphere/chemistry , Biodiversity , Carbon Dioxide/analysis , Fisheries , Food Chain , Human Activities , Ice Cover/chemistry , Introduced Species , Seawater/analysis , Time Factors
5.
Nature ; 562(7726): E5, 2018 10.
Article in English | MEDLINE | ID: mdl-30018346

ABSTRACT

On page 234 of this Perspective, '50% decrease' has been corrected online to '50% increase' in the sentence "The pH of surface waters south of 60° S decreased by 0.2 between 2017 and 2070, equivalent to a 50% increase in the concentration of hydrogen ions since the pre-industrial period1."

6.
Clin Exp Ophthalmol ; 52(7): 761-773, 2024.
Article in English | MEDLINE | ID: mdl-38895754

ABSTRACT

BACKGROUND: Diabetic retinopathy (DR) may worsen during pregnancy, but its course in the postpartum remains poorly understood. Understanding the natural history of DR during and after pregnancy can help determine when sight-threatening DR treatment should be administered. METHODS: A prospective longitudinal cohort study recruited pregnant women with pre-existing type 1 (T1D) or type 2 diabetes from two tertiary Diabetes Antenatal Clinics in Melbourne, Australia. Eye examination results in early pregnancy, late pregnancy, and up to 12-months postpartum were compared to determine DR changes. Two-field fundus photographs and optical coherence tomography scans were used to assess DR severity. RESULTS: Overall, 105 (61.4%) women had at least two eye examinations during the observation period. Mean age was 33.5 years (range 19-51); 54 women (51.4%) had T1D; 63% had HbA1c <7% in early pregnancy. DR progression rate was 23.8% (95% CI 16.4-32.6). Having T1D (RR 4.96, 95% CI 1.83-13.46), pre-existing DR in either eye (RR 4.54, 95% CI 2.39-8.61), and elevated systolic blood pressure (adjusted RR 2.49, 95% CI 1.10-5.66) were associated with increased risk of progression. Sight-threatening progression was observed in 9.5% of women. Among the 19 eyes with progression during pregnancy, 15 eyes remained stable, three eyes progressed, and only one eye regressed in the postpartum. CONCLUSIONS: Nearly 1 in 4 women had DR progression from conception through to 12-months postpartum; almost half of these developing sight-threatening disease. DR progression occurring during pregnancy was found to predominantly remain unchanged, or worsen, after delivery, with very few eyes spontaneously improving postpartum.


Subject(s)
Diabetes Mellitus, Type 1 , Diabetes Mellitus, Type 2 , Diabetic Retinopathy , Disease Progression , Postpartum Period , Pregnancy in Diabetics , Tomography, Optical Coherence , Humans , Female , Pregnancy , Diabetic Retinopathy/physiopathology , Diabetic Retinopathy/diagnosis , Adult , Prospective Studies , Pregnancy in Diabetics/physiopathology , Pregnancy in Diabetics/diagnosis , Tomography, Optical Coherence/methods , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/physiopathology , Young Adult , Middle Aged , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/physiopathology , Glycated Hemoglobin/metabolism , Risk Factors , Follow-Up Studies , Visual Acuity/physiology
7.
Neth Heart J ; 32(4): 148-155, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38376712

ABSTRACT

Cardiac arrest (CA) is a common and potentially avoidable cause of death, while constituting a substantial public health burden. Although survival rates for out-of-hospital cardiac arrest (OHCA) have improved in recent decades, the prognosis for refractory OHCA remains poor. The use of veno-arterial extracorporeal membrane oxygenation during cardiopulmonary resuscitation (ECPR) is increasingly being considered to support rescue measures when conventional cardiopulmonary resuscitation (CPR) fails. ECPR enables immediate haemodynamic and respiratory stabilisation of patients with CA who are refractory to conventional CPR and thereby reduces the low-flow time, promoting favourable neurological outcomes. In the case of refractory OHCA, multiple studies have shown beneficial effects in specific patient categories. However, ECPR might be more effective if it is implemented in the pre-hospital setting to reduce the low-flow time, thereby limiting permanent brain damage. The ongoing ON-SCENE trial might provide a definitive answer regarding the effectiveness of ECPR. The aim of this narrative review is to present the most recent literature available on ECPR and its current developments.

8.
Gut ; 72(8): 1534-1542, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36849226

ABSTRACT

OBJECTIVE: Routine urgent endoscopic retrograde cholangiopancreatography (ERCP) with endoscopic biliary sphincterotomy (ES) does not improve outcome in patients with predicted severe acute biliary pancreatitis. Improved patient selection for ERCP by means of endoscopic ultrasonography (EUS) for stone/sludge detection may challenge these findings. DESIGN: A multicentre, prospective cohort study included patients with predicted severe acute biliary pancreatitis without cholangitis. Patients underwent urgent EUS, followed by ERCP with ES in case of common bile duct stones/sludge, within 24 hours after hospital presentation and within 72 hours after symptom onset. The primary endpoint was a composite of major complications or mortality within 6 months after inclusion. The historical control group was the conservative treatment arm (n=113) of the randomised APEC trial (Acute biliary Pancreatitis: urgent ERCP with sphincterotomy versus conservative treatment, patient inclusion 2013-2017) applying the same study design. RESULTS: Overall, 83 patients underwent urgent EUS at a median of 21 hours (IQR 17-23) after hospital presentation and at a median of 29 hours (IQR 23-41) after start of symptoms. Gallstones/sludge in the bile ducts were detected by EUS in 48/83 patients (58%), all of whom underwent immediate ERCP with ES. The primary endpoint occurred in 34/83 patients (41%) in the urgent EUS-guided ERCP group. This was not different from the 44% rate (50/113 patients) in the historical conservative treatment group (risk ratio (RR) 0.93, 95% CI 0.67 to 1.29; p=0.65). Sensitivity analysis to correct for baseline differences using a logistic regression model also showed no significant beneficial effect of the intervention on the primary outcome (adjusted OR 1.03, 95% CI 0.56 to 1.90, p=0.92). CONCLUSION: In patients with predicted severe acute biliary pancreatitis without cholangitis, urgent EUS-guided ERCP with ES did not reduce the composite endpoint of major complications or mortality, as compared with conservative treatment in a historical control group. TRIAL REGISTRATION NUMBER: ISRCTN15545919.


Subject(s)
Cholangitis , Gallstones , Pancreatitis , Humans , Cholangiopancreatography, Endoscopic Retrograde/adverse effects , Prospective Studies , Endosonography/adverse effects , Patient Selection , Sewage , Sphincterotomy, Endoscopic/adverse effects , Pancreatitis/diagnosis , Gallstones/complications , Gallstones/diagnostic imaging , Gallstones/surgery , Cholangitis/complications , Acute Disease
9.
Pharm Res ; 40(9): 2195-2214, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37634241

ABSTRACT

PURPOSE: To construct a detailed mechanistic and physiologically based biopharmaceutics model capable of predicting 1) device-formulation-tissue interaction during the injection process and 2) binding, degradation, local distribution, diffusion, and drug absorption, following subcutaneous injection. This paper is part of a series and focusses on the first aspect. METHODS: A mathematical model, SubQ-Sim, was developed incorporating the details of the various substructures within the subcutaneous environment together with the calculation of dynamic drug disposition towards the lymph ducts and venous capillaries. Literature was searched to derive key model parameters in healthy and diseased subjects. External factors such as body temperature, exercise, body position, food or stress provide a means to calculate the impact of "life events" on the pharmacokinetics of subcutaneously administered drugs. RESULTS: The model predicts the tissue backpressure time profile during the injection as a function of injection rate, volume injected, solution viscosity, and interstitial fluid viscosity. The shape of the depot and the concentrations of the formulation and proteins in the depot are described. The model enables prediction of formulation backflow following premature needle removal and the resulting formulation losses. Finally, the effect of disease (type 2 diabetes) or the presence of recombinant human hyaluronidase in the formulation on the injection pressure, are explored. CONCLUSIONS: This novel model can successfully predict tissue back pressure, depot dimensions, drug and protein concentration and formulation losses due to incorrect injection, which are all important starting conditions for predicting drug absorption from a subcutaneous dose. The next article will describe the absorption model and validation against clinical data.


Subject(s)
Biopharmaceutics , Diabetes Mellitus, Type 2 , Humans , Biopharmaceutics/methods , Models, Biological , Injections, Subcutaneous , Proteins
10.
Pharm Res ; 40(2): 387-403, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36002614

ABSTRACT

OBJECTIVE: A physiologically based biopharmaceutics model (PBBM) was developed to mechanistically investigate the effect of formulation and food on selumetinib pharmacokinetics. METHODS: Selumetinib is presented as a hydrogen sulfate salt, and in vitro and in vivo data were used to verify the precipitation rate to apply to simulations. Dissolution profiles observed for capsules and granules were used to derive product-particle size distributions for model input. The PBBM incorporated gut efflux and first-pass gut metabolism, based on intravenous and oral pharmacokinetic data, alongside in vitro data for the main enzyme isoform and P-glycoprotein efflux. The PBBM was validated across eight clinical scenarios. RESULTS: The quality-control dissolution method for selumetinib capsules was found to be clinically relevant through PBBM validation. A safe space for capsule dissolution was established using a virtual batch. The effect of food (low fat vs high fat) on capsules and granules was elucidated by the PBBM. For capsules, a lower amount was dissolved in the fed state due to a pH increase in the stomach followed by higher precipitation in the small intestine. First-pass gut extraction is higher for capsules in the fed state due to drug dilution in the stomach chyme and reduced concentration in the lumen. The enteric-coated granules dissolve more slowly than capsules after stomach emptying, attenuating the difference in first-pass gut extraction between prandial states. CONCLUSIONS: The PBBM was instrumental in understanding and explaining the different behaviors of the selumetinib formulations. The model can be used to predict the impact of food in humans.


Subject(s)
Biopharmaceutics , Models, Biological , Adult , Humans , Biopharmaceutics/methods , Solubility , Biological Availability , Capsules , Administration, Oral
11.
Surg Endosc ; 37(2): 1194-1202, 2023 02.
Article in English | MEDLINE | ID: mdl-36163565

ABSTRACT

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) is the procedure of choice to remove sludge/stones from the common bile duct (CBD). In a small but clinically important proportion of patients with suspected choledocholithiasis ERCP is negative. This is undesirable because of ERCP associated morbidity. We aimed to map the diagnostic pathway leading up to ERCP and evaluate ERCP outcome. METHODS: We established a prospective multicenter cohort of patients with suspected CBD stones. We assessed the determinants that were associated with CBD sludge or stone detection upon ERCP. RESULTS: We established a cohort of 707 patients with suspected CBD sludge or stones (62% female, median age 59 years). ERCP was negative for CBD sludge or stones in 155 patients (22%). Patients with positive ERCPs frequently had pre-procedural endoscopic ultrasonography (EUS) or magnetic resonance cholangiopancreatography (MRCP) imaging (44% vs. 35%; P = 0.045). The likelihood of ERCP sludge and stones detection was higher when the time interval between EUS or MRCP and ERCP was less than 2 days (odds ratio 2.35; 95% CI 1.25-4.44; P = 0.008; number needed to harm 7.7). CONCLUSIONS: Even in the current era of society guidelines and use of advanced imaging CBD sludge or stones are absent in one out of five ERCPs performed for suspected CBD stones. The proportion of unnecessary ERCPs is lower in case of pre-procedural EUS or MRCP. A shorter time interval between EUS or MRCP increases the yield of ERCP for suspected CBD stones and should, therefore, preferably be performed within 2 days before ERCP.


Subject(s)
Choledocholithiasis , Gallstones , Humans , Female , Middle Aged , Male , Cholangiopancreatography, Endoscopic Retrograde/methods , Prospective Studies , Sewage , Gallstones/diagnosis , Common Bile Duct
12.
Pharm Res ; 39(8): 1681-1700, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35585448

ABSTRACT

The use of physiologically based pharmacokinetic (PBPK) modeling to support the drug product quality attributes, also known as physiologically based biopharmaceutics modeling (PBBM) is an evolving field and the interest in using PBBM is increasing. The US-FDA has emphasized on the use of patient centric quality standards and clinically relevant drug product specifications over the years. Establishing an in vitro in vivo link is an important step towards achieving the goal of patient centric quality standard. Such a link can aid in constructing a bioequivalence safe space and establishing clinically relevant drug product specifications. PBBM is an important tool to construct a safe space which can be used during the drug product development and lifecycle management. There are several advantages of using the PBBM approach, though there are also a few challenges, both with in vitro methods and in vivo understanding of drug absorption and disposition, that preclude using this approach and therefore further improvements are needed. In this review we have provided an overview of experience gained so far and the current perspective from regulatory and industry point of view. Collaboration between scientists from regulatory, industry and academic fields can further help to advance this field and deliver on promises that PBBM can offer towards establishing patient centric quality standards.


Subject(s)
Biopharmaceutics , Models, Biological , Administration, Oral , Drug Development , Humans , Solubility , Therapeutic Equivalency
13.
Clin Exp Rheumatol ; 40(6): 1076-1083, 2022 Jun.
Article in English | MEDLINE | ID: mdl-34874830

ABSTRACT

OBJECTIVES: We sought laboratory evidence of primary immune deficiency (PID), a condition known to be associated with recurrent infections and autoimmunity, in fibromyalgia (FM). We correlated laboratory findings with a clinical history of recurrent infections and reduced epidermal nerve fiber density (ENFD). METHODS: We prospectively measured serum total and subclass concentrations for IgA, IgG, IgM, IgE, and mannose-binding lectin in 72 adult FM subjects (31 "FM only;" 41 "FM+RA") and compared those results against historical controls. We also administered a novel "Lifetime History of Infections" questionnaire to all FM subjects and 40 apparently healthy, community volunteers matched for age, race, and gender. ENFD values available for 49/72 FM subjects were also correlated with immunoreactant levels. RESULTS: Of FM subjects, 96% (69/72) had ≥3 and 85% (61/72) had ≥4 of 9 immunoreactants below or within the lowermost quartile of historical normal values. Recurrent sinus infections occurred more often in "FM only" (p=0.06), and "FM+RA" subjects (p=0.02) than controls. "FM+RA" subjects had a significantly greater history of recurrent, severe non-sinus infections (p=0.04). The prevalence of total IgA deficiency was significantly greater in "FM only" than in "FM+RA" subjects (p=0.04). We also found a direct correlation between total IgA (p=0.02), IgA1 (p=0.005), and IgG1 (p=0.04) concentrations and ENFD in "FM only" subjects. CONCLUSIONS: Serologic evidence of PID in FM is common and correlates with a clinical history of recurrent sinus and non-sinus infections, and reduced ENFD. This study suggests that PID may be important to diagnostic and therapeutic considerations in FM.


Subject(s)
Fibromyalgia , Primary Immunodeficiency Diseases , Adult , Fibromyalgia/diagnosis , Fibromyalgia/epidemiology , Humans , Immunoglobulin A , Prevalence , Reinfection
14.
Clin Exp Ophthalmol ; 50(7): 757-767, 2022 09.
Article in English | MEDLINE | ID: mdl-35603356

ABSTRACT

BACKGROUND: Diabetic retinopathy (DR) may be affected by pregnancy. The majority of prevalence data regarding DR in pregnancy predate the advent of contemporary guidelines for diabetes management during pregnancy. This study reports DR prevalence and associated risk factors in women with pregestational diabetes during pregnancy and the postpartum in Australia. METHODS: A total of 172 pregnant women with type 1 (T1DM) or type 2 diabetes diagnosed pre-pregnancy were prospectively recruited from two obstetrics hospitals in Melbourne (November 2017-March 2020). Eye examinations were scheduled in each trimester, at 3-, 6-, and 12-months postpartum. DR severity was graded from two-field fundus photographs by an independent grader utilising the Airlie House Classification. Sight-threatening DR (STDR) was defined as the presence of diabetic macular oedema or proliferative DR. RESULTS: Overall, 146 (84.9%) women had at least one eye examination during pregnancy. The mean age was 33.8 years (range 19-51), median diabetes duration was 7.0 years (IQR 3.0-17.0), 71 women (48.6%) had T1DM. DR and STDR prevalence during pregnancy per 100 eyes was 24.3 (95% CI 19.7-29.6) and 9.0 (95% CI 6.1-12.9); while prevalence in the postpartum was 22.2 (95% CI 16.5-29.3) and 10.0 (95% CI 5.4-17.9), respectively. T1DM, longer diabetes duration, higher HbA1c in early pregnancy, and pre-existing nephropathy were significant risk factors. CONCLUSIONS: The prevalence of DR in pregnant women was similar to the non-pregnant diabetic population in Australia. One in nine participants had STDR during pregnancy and the postpartum, highlighting the need to optimise DR management guidelines in pregnancy given the significant risk of vision loss.


Subject(s)
Diabetes Mellitus, Type 1 , Diabetes Mellitus, Type 2 , Diabetic Retinopathy , Adult , Cross-Sectional Studies , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/epidemiology , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/epidemiology , Diabetic Retinopathy/complications , Diabetic Retinopathy/diagnosis , Diabetic Retinopathy/epidemiology , Female , Glycated Hemoglobin , Humans , Male , Middle Aged , Postpartum Period , Pregnancy , Prevalence , Risk Factors , Young Adult
15.
Lancet ; 396(10245): 167-176, 2020 07 18.
Article in English | MEDLINE | ID: mdl-32682482

ABSTRACT

BACKGROUND: It remains unclear whether urgent endoscopic retrograde cholangiopancreatography (ERCP) with biliary sphincterotomy improves the outcome of patients with gallstone pancreatitis without concomitant cholangitis. We did a randomised trial to compare urgent ERCP with sphincterotomy versus conservative treatment in patients with predicted severe acute gallstone pancreatitis. METHODS: In this multicentre, parallel-group, assessor-masked, randomised controlled superiority trial, patients with predicted severe (Acute Physiology and Chronic Health Evaluation II score ≥8, Imrie score ≥3, or C-reactive protein concentration >150 mg/L) gallstone pancreatitis without cholangitis were assessed for eligibility in 26 hospitals in the Netherlands. Patients were randomly assigned (1:1) by a web-based randomisation module with randomly varying block sizes to urgent ERCP with sphincterotomy (within 24 h after hospital presentation) or conservative treatment. The primary endpoint was a composite of mortality or major complications (new-onset persistent organ failure, cholangitis, bacteraemia, pneumonia, pancreatic necrosis, or pancreatic insufficiency) within 6 months of randomisation. Analysis was by intention to treat. This trial is registered with the ISRCTN registry, ISRCTN97372133. FINDINGS: Between Feb 28, 2013, and March 1, 2017, 232 patients were randomly assigned to urgent ERCP with sphincterotomy (n=118) or conservative treatment (n=114). One patient from each group was excluded from the final analysis because of cholangitis (urgent ERCP group) and chronic pancreatitis (conservative treatment group) at admission. The primary endpoint occurred in 45 (38%) of 117 patients in the urgent ERCP group and in 50 (44%) of 113 patients in the conservative treatment group (risk ratio [RR] 0·87, 95% CI 0·64-1·18; p=0·37). No relevant differences in the individual components of the primary endpoint were recorded between groups, apart from the occurrence of cholangitis (two [2%] of 117 in the urgent ERCP group vs 11 [10%] of 113 in the conservative treatment group; RR 0·18, 95% CI 0·04-0·78; p=0·010). Adverse events were reported in 87 (74%) of 118 patients in the urgent ERCP group versus 91 (80%) of 114 patients in the conservative treatment group. INTERPRETATION: In patients with predicted severe gallstone pancreatitis but without cholangitis, urgent ERCP with sphincterotomy did not reduce the composite endpoint of major complications or mortality, compared with conservative treatment. Our findings support a conservative strategy in patients with predicted severe acute gallstone pancreatitis with an ERCP indicated only in patients with cholangitis or persistent cholestasis. FUNDING: The Netherlands Organization for Health Research and Development, Fonds NutsOhra, and the Dutch Patient Organization for Pancreatic Diseases.


Subject(s)
Cholangiopancreatography, Endoscopic Retrograde/methods , Conservative Treatment/methods , Gallstones/therapy , Pancreatitis/therapy , Sphincterotomy, Endoscopic/methods , Acute Disease , Aged , Combined Modality Therapy , Female , Gallstones/complications , Gallstones/etiology , Humans , Male , Treatment Outcome
16.
Mar Drugs ; 19(2)2021 Jan 23.
Article in English | MEDLINE | ID: mdl-33498789

ABSTRACT

Aurilides are a class of depsipeptides occurring mainly in marine cyanobacteria. Members of the aurilide family have shown to exhibit strong cytotoxicity against various cancer cell lines. These compounds bear a pentapeptide, a polyketide, and an α-hydroxy ester subunit in their structure. A large number of remarkable studies on aurilides have emerged since 1996. This comprehensive account summarizes the biological activities and total syntheses of natural compounds of the aurilide family as well as their synthetic analogues.


Subject(s)
Aquatic Organisms , Biological Products/chemistry , Depsipeptides/biosynthesis , Depsipeptides/chemistry , Animals , Biological Products/therapeutic use , Depsipeptides/therapeutic use , Humans , Neoplasms/drug therapy
17.
Inorg Chem ; 59(23): 17149-17161, 2020 Dec 07.
Article in English | MEDLINE | ID: mdl-33231437

ABSTRACT

In search of suitable simulants for aerosol uranium waste products from Plutonium Uranium Redox Extraction (PUREX) process burns, a series of lanthanide nitrate hydrates ([Ln(κ2-NO3)3·nH2O]) were dissolved in the presence of tributylphosphate (O═P(O(CH2)3CH3)3) referred to as TBP) in kerosene or triphenylphosphate (O═P(O(C6H5) referred to as TPhP) in acetone. The crystal structure of the TPhP derivatives of the lanthanide nitrate series and uranium nitrate were solved as [Ln(κ2-NO3)3(TPhP)3] (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) and [U(O)2(κ2-NO3)2(TPhP)2] (U), respectively. The lanthanide-TBP, Ln, and U were further characterized using FTIR spectroscopy, 31P NMR spectroscopy, thermogravimetric analysis, and X-ray fluorescence spectroscopy. Further, thermal treatment of the lanthanide-TBP, Ln, and U using a box furnace to mimic pyrolysis conditions was found by PXRD analyses to generate a phosphate phase [LnP3O9 or UP2O7) for all systems. The resultant nuclear waste fire contaminant particulates will impact both aerosol transport and toxicity assessments.

18.
Gen Dent ; 68(5): 61-65, 2020.
Article in English | MEDLINE | ID: mdl-32857051

ABSTRACT

The aim of this research was to determine the color stability of 3 gingival shades of dental restorative materials, Amaris Gingiva, Beautiful II Gingiva, and PermaFlo Pink, compared to a tooth-colored nanohybrid composite, Filtek Z250. Twenty-five specimens of each composite were fabricated in polytetrafluoroethylene-coated stainless steel molds and polished using a 4-step polishing regimen. The specimens were randomly assigned to groups for immersion in 1 of 5 solutions (n = 5): distilled water (control), red wine, tea, coffee, or curry (curry powder [containing turmeric] in a solution with distilled water). A desktop spectrophotometer was used to perform color measurements within the Commission Internationale de l'Eclairage L*a*b* color space, and mean overall color (E*) was calculated for each group before and after immersion for 7 days. The mean E* values of each composite before and after immersion were compared using paired t tests at the P < 0.05 level of significance. For all of the tested restorative materials, immersion in a solution of curry produced the greatest increase in mean E* values (P < 0.0001), with E* increasing 32-fold for Amaris Gingiva specimens, 27-fold for Beautiful II Gingiva, 34-fold for PermaFlo Pink, and 2-fold for Filtek Z250. There were smaller, but still significant, increases in E* for Amaris Gingiva, Beautiful II Gingiva, and PermaFlo Pink when immersed in coffee (P < 0.05). Curry caused the greatest change in E* values for all of the tested restorative materials, indicating that curry seasonings based on turmeric can cause unacceptable color change in all of the tested materials and such change can happen in a relatively short time. Coffee also has the potential to cause unacceptable color change in gingival shades of composite materials.


Subject(s)
Composite Resins , Gingiva , Coffee , Color , Dental Materials , Materials Testing , Spectrophotometry , Surface Properties
20.
Encephale ; 45(2): 182-187, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30503684

ABSTRACT

BACKGROUND: Autism spectrum disorder (ASD) is a heterogeneous group of neurodevelopmental disorders which core symptoms are impairments in socio-communication and repetitive symptoms and stereotypies. Although not cardinal symptoms per se, motor impairments are fundamental aspects of ASD. These impairments are associated with postural and motor control disabilities that we investigated using computational modeling and developmental robotics through human-machine interaction paradigms. METHOD: First, in a set of studies involving a human-robot posture imitation, we explored the impact of 3 different groups of partners (including a group of children with ASD) on robot learning by imitation. Second, using an ecological task, i.e. a real-time motor imitation with a tightrope walker (TW) avatar, we investigated interpersonal synchronization, motor coordination and motor control during the task in children with ASD (n=29), TD children (n=39) and children with developmental coordination disorder (n=17, DCD). RESULTS: From the human-robot experiments, we evidenced that motor signature at both groups' and individuals' levels had a key influence on imitation learning, posture recognition and identity recognition. From the more dynamic motor imitation paradigm with a TW avatar, we found that interpersonal synchronization, motor coordination and motor control were more impaired in children with ASD compared to both TD children and children with DCD. Taken together these results confirm the motor peculiarities of children with ASD despite imitation tasks were adequately performed. DISCUSSION: Studies from human-machine interaction support the idea of a behavioral signature in children with ASD. However, several issues need to be addressed. Is this behavioral signature motoric in essence? Is it possible to ascertain that these peculiarities occur during all motor tasks (e.g. posture, voluntary movement)? Could this motor signature be considered as specific to autism, notably in comparison to DCD that also display poor motor coordination skills? We suggest that more work comparing the two conditions should be implemented, including analysis of kinematics and movement smoothness with sufficient measurement quality to allow spectral analysis.


Subject(s)
Autism Spectrum Disorder/diagnosis , Computer Simulation , Diagnostic Techniques, Neurological/trends , Motor Activity/physiology , Motor Skills Disorders/diagnosis , Posture/physiology , Robotics , Autism Spectrum Disorder/classification , Autism Spectrum Disorder/physiopathology , Child , Diagnosis, Computer-Assisted/methods , Diagnosis, Computer-Assisted/trends , Female , Humans , Machine Learning , Male , Motor Skills Disorders/psychology , Robotics/methods , Robotics/trends
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