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1.
Nature ; 569(7757): 546-550, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31118523

RESUMO

The recovery of the stratospheric ozone layer relies on the continued decline in the atmospheric concentrations of ozone-depleting gases such as chlorofluorocarbons1. The atmospheric concentration of trichlorofluoromethane (CFC-11), the second-most abundant chlorofluorocarbon, has declined substantially since the mid-1990s2. A recently reported slowdown in the decline of the atmospheric concentration of CFC-11 after 2012, however, suggests that global emissions have increased3,4. A concurrent increase in CFC-11 emissions from eastern Asia contributes to the global emission increase, but the location and magnitude of this regional source are unknown3. Here, using high-frequency atmospheric observations from Gosan, South Korea, and Hateruma, Japan, together with global monitoring data and atmospheric chemical transport model simulations, we investigate regional CFC-11 emissions from eastern Asia. We show that emissions from eastern mainland China are 7.0 ± 3.0 (±1 standard deviation) gigagrams per year higher in 2014-2017 than in 2008-2012, and that the increase in emissions arises primarily around the northeastern provinces of Shandong and Hebei. This increase accounts for a substantial fraction (at least 40 to 60 per cent) of the global rise in CFC-11 emissions. We find no evidence for a significant increase in CFC-11 emissions from any other eastern Asian countries or other regions of the world where there are available data for the detection of regional emissions. The attribution of any remaining fraction of the global CFC-11 emission rise to other regions is limited by the sparsity of long-term measurements of sufficient frequency near potentially emissive regions. Several considerations suggest that the increase in CFC-11 emissions from eastern mainland China is likely to be the result of new production and use, which is inconsistent with the Montreal Protocol agreement to phase out global chlorofluorocarbon production by 2010.

2.
Phys Rev Lett ; 132(13): 131001, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613296

RESUMO

We searched for antideuterons (d[over ¯]'s) in the 4.7×10^{9} cosmic-ray events observed during the BESS-Polar II flight at solar minimum in 2007-2008 but found no candidates. The resulting 95% C.L. upper limit on the d[over ¯] flux is 6.7×10^{-5} (m^{2} s sr GeV/n)^{-1} in an energy range from 0.163 to 1.100 GeV/n. The result has improved by more than a factor of 14 from the upper limit of BESS97, which had a potential comparable to that of BESS-Polar II in the search for cosmic-origin d[over ¯]'s and was conducted during the former solar minimum. The upper limit of d[over ¯] flux from BESS-Polar II is the first result achieving the sensitivity to constrain the latest theoretical predictions.

3.
J Nutr ; 154(1): 41-48, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37315794

RESUMO

BACKGROUND: Rapid gastric emptying is associated with obesity and overeating, whereas delayed gastric emptying is associated with anorexia. Acute effects of exercise on gastric emptying have been investigated extensively, but the influence of habitual physical activity on gastric emptying and transit time in other regions of the gastrointestinal tract is poorly understood. OBJECTIVE: The objective was to investigate associations between objectively measured habitual physical activity and gastrointestinal transit times in adults with varying degrees of adiposity. METHODS: 50 adults (58% women) were included in this cross-sectional study. Physical activity was measured by an accelerometer placed on the lower back for 7 d. Gastric emptying time, small bowel transit time, colonic transit time, and whole gut transit time were simultaneously evaluated by a wireless motility capsule, which was ingested together with a standardized mixed meal. Linear regression models were applied to assess the associations of total activity counts and time spent at different intensities-sedentary activity (0-100 counts/min), low light activity (101-759 counts/min), high light activity (760-1951 counts/min); moderate and vigorous activity (≥1952 counts/min)) with gastrointestinal transit times. RESULTS: Median [Q1; Q3] age was 56.5 [46.6-65.5] y, and body mass index (BMI) was 32.1 [28.5-35.1] kg/m2. For every additional hour spent performing high light intensity physical activity, colonic transit time was 25.5 % [95% CI: 3.10, 42.7] more rapid (P = 0.028), and whole gut transit time was 16.2 % [95% CI: 1.84, 28.4] more rapid (P = 0.028) when adjusted for sex, age, and body fat. No other associations were observed. CONCLUSIONS: More time spent on physical activity at high light intensity was associated with more rapid colonic and whole gut transit time, independent of age, sex, and body fat, whereas other intensities of physical activity and gastrointestinal transit times were not associated. TRIAL REGISTRATION: Clinicaltrials.gov IDs (NCT03894670, NCT03854656).


Assuntos
Trânsito Gastrointestinal , Sobrepeso , Adulto , Humanos , Feminino , Masculino , Estudos Transversais , Obesidade , Exercício Físico , Esvaziamento Gástrico
4.
J Endocrinol Invest ; 2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38493245

RESUMO

BACKGROUND: Menopause, a dramatical estrogen-deficient condition, is considered the most significant milestone in women's health. PURPOSE: To investigate the metabolite changes attributed to estrogen deficiency using random forest (RF)-based machine learning (ML) modeling strategy in ovariectomized (OVX) mice as well as determine the clinical relevance of selected metabolites in older women. METHODS AND RESULTS: Untargeted and targeted metabolomic analyses revealed that metabolites related to TCA cycle, sphingolipids, phospholipids, fatty acids, and amino acids, were significantly changed in the plasma and/or muscle of OVX mice. Subsequent ML classifiers based on RF algorithm selected alpha-ketoglutarate (AKG), arginine, carnosine, ceramide C24, phosphatidylcholine (PC) aa C36:6, and PC ae C42:3 in plasma as well as PC aa 34:1, PC aa C34:3, PC aa C36:5, PC aa C32:1, PC aa C36:2, and sphingosine in muscle as top featured metabolites that differentiate the OVX mice from the sham-operated group. When circulating levels of AKG, arginine, and carnosine, which showed the most significant changes in OVX mice blood, were measured in postmenopausal women, higher plasma AKG levels were associated with lower bone mass, weak grip strength, poor physical performance, and increased frailty risk. CONCLUSIONS: Metabolomics- and ML-based methods identified the key metabolites of blood and muscle that were significantly changed after ovariectomy in mice, and the clinical implication of several metabolites was investigated by looking at their correlation with body composition and frailty-related parameters in postmenopausal women. These findings provide crucial context for understanding the diverse physiological alterations caused by estrogen deficiency in women.

5.
Anim Genet ; 55(4): 612-620, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38866396

RESUMO

Neuronal ceroid lipofuscinosis (NCL) is a group of neurodegenerative disorders that occur in humans, dogs, and several other species. NCL is characterised clinically by progressive deterioration of cognitive and motor function, epileptic seizures, and visual impairment. Most forms present early in life and eventually lead to premature death. Typical pathological changes include neuronal accumulation of autofluorescent, periodic acid-Schiff- and Sudan black B-positive lipopigments, as well as marked loss of neurons in the central nervous system. Here, we describe a 19-month-old Schapendoes dog, where clinical signs were indicative of lysosomal storage disease, which was corroborated by pathological findings consistent with NCL. Whole genome sequencing of the affected dog and both parents, followed by variant calling and visual inspection of known NCL genes, identified a missense variant in CLN6 (c.386T>C). The variant is located in a highly conserved region of the gene and predicted to be harmful, which supports a causal relationship. The identification of this novel CLN6 variant enables pre-breeding DNA-testing to prevent future cases of NCL6 in the Schapendoes breed, and presents a potential natural model for NCL6 in humans.


Assuntos
Doenças do Cão , Mutação de Sentido Incorreto , Lipofuscinoses Ceroides Neuronais , Lipofuscinoses Ceroides Neuronais/genética , Lipofuscinoses Ceroides Neuronais/veterinária , Animais , Cães/genética , Doenças do Cão/genética , Proteínas de Membrana/genética , Masculino , Feminino
6.
Acta Paediatr ; 113(6): 1446-1452, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38329165

RESUMO

AIMS: The aim was to analyse the use and safety of bisphosphonate treatment for metabolic bone complications in paediatric cancer patients. METHODS: We retrospectively describe our experience with bisphosphonate treatment in 25 childhood cancer patients (aged <18 years) in a single tertiary hospital between 1999 and 2020. RESULTS: The most common primary diagnosis was acute lymphoblastic leukaemia (n = 16) and Hodgkin lymphoma (n = 3). Eleven patients (44%) had received allogeneic stem cell transplantation and two patients autologous stem cell transplantation. Sixteen patients (64%) had been treated with radiotherapy, either total-body (n = 11) or local (n = 5). The main indication for bisphosphonates was osteoporosis with vertebral compression fractures in 13/25, osteonecrosis in 6/25 and hypercalcaemia in 2/25. The bisphosphonate treatment was started on average 13 (range 0-76) months after the diagnosis of the bone complication. Bisphosphonate treatment lasted between weeks (hypercalcaemia) to 5 years (severe osteoporosis). Mild, non-symptomatic hypophosphatemia (n = 8), hypocalcaemia (n = 6) and moderate, transient pain (n = 6) were the most common adverse effects. No severe side effects were observed even when bisphosphonates were administered concomitantly with chemotherapy. Bone mineral density significantly improved with the bisphosphonate treatment (mean lumbar spine Z-score -1.17 vs. -0.07, p < 0.001). CONCLUSION: Bisphosphonate treatment was well tolerated in this paediatric patient cohort.


Assuntos
Conservadores da Densidade Óssea , Difosfonatos , Centros de Atenção Terciária , Humanos , Feminino , Masculino , Criança , Estudos Retrospectivos , Difosfonatos/uso terapêutico , Difosfonatos/efeitos adversos , Adolescente , Pré-Escolar , Conservadores da Densidade Óssea/uso terapêutico , Conservadores da Densidade Óssea/efeitos adversos , Neoplasias/complicações , Osteoporose/tratamento farmacológico , Doenças Ósseas Metabólicas/etiologia , Doenças Ósseas Metabólicas/tratamento farmacológico , Lactente
7.
Euro Surveill ; 29(25)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38904114

RESUMO

BackgroundTo be better prepared for emerging wildlife-borne zoonoses, we need to strengthen wildlife disease surveillance.AimThe aim of this study was to create a topical overview of zoonotic pathogens in wildlife species to identify knowledge gaps and opportunities for improvement of wildlife disease surveillance.MethodsWe created a database, which is based on a systematic literature review in Embase focused on zoonotic pathogens in 10 common urban wildlife mammals in Europe, namely brown rats, house mice, wood mice, common voles, red squirrels, European rabbits, European hedgehogs, European moles, stone martens and red foxes. In total, we retrieved 6,305 unique articles of which 882 were included.ResultsIn total, 186 zoonotic pathogen species were described, including 90 bacteria, 42 helminths, 19 protozoa, 22 viruses and 15 fungi. Most of these pathogens were only studied in one single animal species. Even considering that some pathogens are relatively species-specific, many European countries have no (accessible) data on zoonotic pathogens in these relevant animal species. We used the Netherlands as an example to show how this database can be used by other countries to identify wildlife disease surveillance gaps on a national level. Only 4% of all potential host-pathogen combinations have been studied in the Netherlands.ConclusionsThis database comprises a comprehensive overview that can guide future research on wildlife-borne zoonotic diseases both on a European and national scale. Sharing and expanding this database provides a solid starting point for future European-wide collaborations to improve wildlife disease surveillance.


Assuntos
Animais Selvagens , Zoonoses , Animais , Animais Selvagens/microbiologia , Europa (Continente)/epidemiologia , Zoonoses/epidemiologia , Bases de Dados Factuais , Humanos , Ratos , Sciuridae/microbiologia , Ouriços/microbiologia , Coelhos , Camundongos , Vigilância da População , Raposas/microbiologia , Raposas/parasitologia
8.
Adv Neonatal Care ; 24(2): 141-150, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38547481

RESUMO

BACKGROUND: The presence of psychospiritual supports and interventions for neonatal intensive care unit (NICU) parents is unclear. PURPOSE: This systematic review examines the psychological and medical literature for psychospiritual interventions designed to support parents' mental health and psychological well-being during or after the NICU experience. DATA SOURCES: Data sources include PubMed, PsycINFO, and Cochrane Library (Cochrane Database of Systemic Reviews, Cochrane Central Register of Controlled Trials) with peer-reviewed studies published between 2013 and 2023. STUDY SELECTION: Peer-reviewed studies that included spiritual and psychological intervention components focused on supporting parents during or after the NICU were included for this systematic review. There were 42 records located in 3 databases ultimately yielding 4 peer-reviewed studies that met inclusion criteria. Articles must have been written in English and evaluate parents'/caregivers' mental health/psychological well-being in relation to a psychospiritual intervention. DATA EXTRACTION: Because of the small number of studies, article summaries are provided within the results section and were written by the first author with approval by the second and third authors. RESULTS: Results indicated that when psychological (focus on coping) and spiritual components were included psychological and well-being outcomes were better for NICU parents. IMPLICATIONS FOR PRACTICE AND RESEARCH: The inclusion of psychological and spiritual aspects of coping and supportive care is necessary for the best family-centered NICU care. More work needs to be done to develop psychospiritual supports and include fathers in these endeavors as most work occurs with mothers. Nurses need support and training to facilitate family-centered care with a focus on parents' psychospiritual needs.


Assuntos
Unidades de Terapia Intensiva Neonatal , Saúde Mental , Recém-Nascido , Feminino , Humanos , Bem-Estar Psicológico , Pais/psicologia , Mães
9.
Occup Med (Lond) ; 74(2): 152-160, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38330390

RESUMO

BACKGROUND: Irregular menstruation is a major health problem among women, although its association with nightshift work remains controversial. AIMS: To study the association between nightshift work and irregular menstrual cycle among female workers and investigate any differences according to sleep quality, working hours or obesity. METHODS: This study included female workers who underwent health examinations from 2012 to 2019. Nightshift work, working hours, sleep quality and menstrual cycles were assessed using self-administered questionnaires. Irregular menstrual cycle was defined as self-reported irregular or ≥36 days. Adjusted odds ratios and 95% confidence intervals (CIs) were calculated by multivariable logistic regression; adjusted hazard ratios (95% CIs) for incident irregular menstrual cycle were calculated by Cox proportional hazard models with time-dependent analysis. RESULTS: The study participants were 87 147 in the cross-sectional study and 41 516 in the longitudinal study. After adjusting for all covariates in the cross-sectional analyses, the odds ratio for prevalent irregular menstrual cycle among female nightshift workers versus the reference was 1.26 (95% CI 1.2-1.33). In the cohort study, the adjusted hazard ratio for incident irregular menstrual cycle among nightshift workers was 1.95 (95% CI 1.61-2.35) in the period after 6 years. No significant differences were observed among subgroups stratified by sleep quality, working hours or obesity. CONCLUSIONS: Nightshift work is associated with an increased risk of both prevalent and incident irregular menstrual cycle in female workers without significant interactions by sleep quality, working hours or obesity.


Assuntos
Ciclo Menstrual , Distúrbios Menstruais , Feminino , Humanos , Seguimentos , Estudos de Coortes , Estudos Transversais , Estudos Longitudinais , Distúrbios Menstruais/etiologia , Distúrbios Menstruais/complicações , Obesidade/epidemiologia , Obesidade/complicações
10.
Rhinology ; 62(2): 130-142, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-37943054

RESUMO

BACKGROUND: Chemosensory dysfunction has been reported to be involved in the pathogenesis of Alzheimer’s disease (AD). Compared with olfaction, gustatory dysfunction in AD has not been evaluated in depth. We reviewed previously published studies regarding gustatory dysfunction in patients with AD compared with healthy controls. METHODS: A systematic review was conducted by searching the MEDLINE, Cochrane Library, Embase, and PubMed databases covering publications from January 2000 to February 2023. The search was performed using the keyword "Alzheimer* AND (gustatory OR taste OR gustation)." Only studies that performed gustatory function testing and compared the results between patients with AD and healthy controls were included. A random-effects meta-analysis was performed. RESULTS: Twelve articles were finally included, and various gustatory tests including taste strips, the taste disk test, taste solutions, and subjective questionnaires were applied. Overall gustatory function based on the taste strip test was significantly decreased in patients with AD compared with controls in two out of three papers. The overall gustatory function of patients with AD was significantly decreased in all studies based on the taste disk and taste solution tests. We also found that the sweet taste test showed low heterogeneity across all the included studies, and there was low publication bias. In studies using subjective questionnaires, gustatory function was not significantly different between patients with AD and healthy controls in the meta-analysis. CONCLUSIONS: Based on these studies, gustatory dysfunction diagnosed by gustatory function testing was closely related to AD. However, the results of subjective questionnaires were not significantly different between patients with AD and healthy controls in the current meta-analysis. As the number of studies and enrolled subjects was limited and unified gustatory function testing was lacking, further studies are needed to confirm this relationship.


Assuntos
Doença de Alzheimer , Transtornos do Olfato , Humanos , Paladar , Doença de Alzheimer/complicações , Distúrbios do Paladar/diagnóstico , Disgeusia/diagnóstico , Olfato , Transtornos do Olfato/diagnóstico
11.
Cancer Immunol Immunother ; 72(7): 2099-2111, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36823323

RESUMO

Bempegaldesleukin (BEMPEG), a CD122-preferential IL2 pathway agonist, has been shown to induce proliferation and activation of NK cells. NK activation is dependent on the balance of inhibitory and excitatory signals transmitted by NK receptors, including Fc-gamma receptors (FCγRs) and killer immunoglobulin-like receptors (KIRs) along with their KIR-ligands. The repertoire of KIRs/KIR-ligands an individual inherits and the single-nucleotide polymorphisms (SNPs) of FCγRs can influence NK function and affect responses to immunotherapies. In this retrospective analysis of the single-arm PIVOT-02 trial, 200 patients with advanced solid tumors were genotyped for KIR/KIR-ligand gene status and FCγR SNP status and evaluated for associations with clinical outcome. Patients with inhibitory KIR2DL2 and its ligand (HLA-C1) observed significantly greater tumor shrinkage (TS, median change -13.0 vs. 0%) and increased PFS (5.5 vs. 3.3 months) and a trend toward improved OR (31.2 vs. 19.5%) compared to patients with the complementary genotype. Furthermore, patients with KIR2DL2 and its ligand together with inhibitory KIR3DL1 and its ligand (HLA-Bw4) had improved OR (36.5 vs. 19.6%), greater TS (median change -16.1 vs. 0%), and a trend toward prolonged PFS (8.4 vs. 3.6 months) as compared to patients with the complementary genotype. FCγR polymorphisms did not influence OR/PFS/TS.These data show that clinical response to BEMPEG plus nivolumab treatment in the PIVOT-02 trial may be associated with the repertoire of KIR/KIR-ligands an individual inherits. Further investigation and validation of these results may enable KIR/KIR-ligand genotyping to be utilized prospectively for identifying patients likely to benefit from certain cancer immunotherapy regimens.


Assuntos
Neoplasias , Nivolumabe , Humanos , Nivolumabe/uso terapêutico , Ligantes , Estudos Retrospectivos , Receptores de IgG/genética , Receptores KIR/genética , Receptores KIR/metabolismo , Genótipo , Polimorfismo de Nucleotídeo Único , Neoplasias/tratamento farmacológico , Neoplasias/genética
12.
J Synchrotron Radiat ; 30(Pt 1): 242-250, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36601943

RESUMO

The PERCIVAL detector is a CMOS imager designed for the soft X-ray regime at photon sources. Although still in its final development phase, it has recently seen its first user experiments: ptychography at a free-electron laser, holographic imaging at a storage ring and preliminary tests on X-ray photon correlation spectroscopy. The detector performed remarkably well in terms of spatial resolution achievable in the sample plane, owing to its small pixel size, large active area and very large dynamic range; but also in terms of its frame rate, which is significantly faster than traditional CCDs. In particular, it is the combination of these features which makes PERCIVAL an attractive option for soft X-ray science.


Assuntos
Fótons , Radiografia , Raios X
13.
Osteoporos Int ; 34(5): 1005-1009, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36622389

RESUMO

Hajdu-Cheney syndrome (HCS) is an inherited skeletal disorder caused by mutations in the Notch homolog protein 2 gene (NOTCH2). Treatment of this rare disease is challenging because there are no established guidelines worldwide. Previous case reports using bisphosphonates, denosumab, or teriparatide suggested that curative treatment for HCS did not exist yet in terms of preventing the disease progression. Therefore, the efficacy of romosozumab for osteoporosis in patients with HCS needs to be evaluated. Herein, we report the case of a 43-year-old woman who had progressive acro-osteolysis and repeated fractures since the age of 29 years. Next-generation sequencing confirmed HCS with a mutation at nucleotide 6758G>A, leading to Trp2253Ter replacement in NOTCH2. Romosozumab treatment was initiated because she had already received bisphosphonate for more than 10 years at other hospitals. After 1 year of romosozumab treatment, the bone mineral density (BMD) increased by 10.2%, 6.3%, and 1.3%, with Z scores of -2.9, -1.6, and -1.2 at the lumbar spine, femoral neck, and total hip, respectively. In addition, C-telopeptide was suppressed by 26.4% (0.121 to 0.089 ng/mL), and procollagen type I N-terminal propeptide increased by 18.7% (25.2 to 29.9 ng/mL). This was the first report of romosozumab treatment in patient with osteoporosis and HCS in Korea. One year of romosozumab treatment provided substantial gains in BMD with maintaining the last acro-osteolytic status without deteriorating, representing a possible treatment option for HCS.


Assuntos
Conservadores da Densidade Óssea , Síndrome de Hajdu-Cheney , Osteoporose , Feminino , Humanos , Adulto , Síndrome de Hajdu-Cheney/complicações , Síndrome de Hajdu-Cheney/tratamento farmacológico , Síndrome de Hajdu-Cheney/genética , Osteoporose/etiologia , Anticorpos Monoclonais/uso terapêutico , Densidade Óssea , Difosfonatos , Conservadores da Densidade Óssea/uso terapêutico
14.
Phys Rev Lett ; 131(20): 201802, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38039466

RESUMO

We search for energetic electron recoil signals induced by boosted dark matter (BDM) from the galactic center using the COSINE-100 array of NaI(Tl) crystal detectors at the Yangyang Underground Laboratory. The signal would be an excess of events with energies above 4 MeV over the well-understood background. Because no excess of events are observed in a 97.7 kg·yr exposure, we set limits on BDM interactions under a variety of hypotheses. Notably, we explored the dark photon parameter space, leading to competitive limits compared to direct dark photon search experiments, particularly for dark photon masses below 4 MeV and considering the invisible decay mode. Furthermore, by comparing our results with a previous BDM search conducted by the Super-Kamionkande experiment, we found that the COSINE-100 detector has advantages in searching for low-mass dark matter. This analysis demonstrates the potential of the COSINE-100 detector to search for MeV electron recoil signals produced by the dark sector particle interactions.

15.
Chemistry ; 29(6): e202203035, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36301715

RESUMO

A general synthetic approach to halogenated tetraaryl-ammonium salts has been developed and illustrated crystallographically. Bromide ammonium salts used as common synthetic intermediates together with Suzuki coupling of these bromides to a family of boronic acids provided a simplified strategy for arylation. Resolution of the C2 subset of spiro-bicarbazolium derivatives led to the first examples of enantiopure spiro-bicarbazoliums and the assignment of their absolute configuration by comparison of computational and experimental electronic circular dichroism (ECD) spectra. An ECD comparison with Prelog's spirobifluorenes is provided. The absolute configuration of the meta-bromide spiro-bicarbazolium salt was confirmed by anomalous scattering. Cruciform and stellate tetra-substituted salts provide a test of the limits of the methodology, and their structures suggest them to be candidates for MOF building blocks.

16.
Chemistry ; 29(34): e202300624, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-36867728

RESUMO

Polycyclic aromatic endoperoxides are important sources of singlet oxygen (1 O2 ) and their formation from polyacenes is well established. Anthracene carboxyimides are of particular interest as they exhibit excellent antitumor activity and possess unique photochemical properties. However, the photooxygenation of the synthetically versatile anthracene carboxyimide moiety has not been reported due to its competing [4+4] photodimerization reaction. Herein, we describe the reversible photo-oxidation of an anthracene carboxyimide. X-ray crystallographic analysis surprisingly revealed the formation of a racemic mixture of chiral hydroperoxides, rather than the expected endoperoxide. The photoproduct undergoes both photo- and thermolysis to form 1 O2 . Activation parameters were derived for the thermolysis and the mechanisms of photooxygenation and thermolysis are discussed. The anthracene carboxyimide also showed high selectivity and sensitivity for nitrite anions in acidic aqueous media and possessed stimuli-responsive behaviour.

17.
Cell ; 133(7): 1188-201, 2008 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-18585353

RESUMO

Chromosome movement is prominent during meiosis. Here, using a combination of in vitro and in vivo approaches, we elucidate the basis for dynamic mid-prophase telomere-led chromosome motion in budding yeast. Diverse findings reveal a process in which, at the pachytene stage, individual telomere/nuclear envelope (NE) ensembles attach passively to, and then move in concert with, nucleus-hugging actin cables that are continuous with the global cytoskeletal actin network. Other chromosomes move in concert with lead chromosome(s). The same process, in modulated form, explains the zygotene "bouquet" configuration in which, immediately preceding pachytene, chromosome ends colocalize dynamically in a restricted region of the NE. Mechanical properties of the system and biological roles of mid-prophase movement for meiosis, including recombination, are discussed.


Assuntos
Actinas/metabolismo , Cromossomos Fúngicos/metabolismo , Meiose , Membrana Nuclear/metabolismo , Saccharomyces cerevisiae/citologia , Transporte Biológico , Núcleo Celular/metabolismo , Citoesqueleto/metabolismo , Saccharomyces cerevisiae/metabolismo
18.
Ultrasound Obstet Gynecol ; 61(5): 593-600, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36273401

RESUMO

OBJECTIVE: To investigate the criteria, based on fetal TR waveforms in late gestation, to predict biventricular circulation (BV) after birth in cases of tricuspid valve dysplasia (TVD) or Ebstein's anomaly diagnosed during the fetal period. METHODS: We included 35 consecutive cases diagnosed with TVD or Ebstein's anomaly during the fetal period between January 2008 and December 2021 at Kanagawa Children's Medical Center, Kanagawa, Japan. The maximum velocity and change in pressure over time of tricuspid regurgitation (TR) jet (dP/dt), estimated using TR waveforms obtained during the late-gestation period (gestational age ≥ 28 weeks), were collected from patient records. dP/dt was calculated by dividing the change in estimated right ventricular pressure obtained using Bernoulli's principle by the time taken for the TR maximum velocity to change from one-third to two-thirds of its peak value. The outcome was divided into four categories: BV, single ventricular circulation, neonatal death and fetal death. Patients with BV were included in the BV group, while patients with single ventricular circulation, neonatal death or fetal death were included in the non-BV (NBV) group. RESULTS: Overall, 19 and 16 patients were included in the BV and NBV groups, respectively. The median TR maximum velocity was 3.3 (range, 2.4-3.6) m/s in the BV group and 1.9 (range, 1.0-3.3) m/s in the NBV group. There were no cases of postnatal BV in fetuses with TR maximum velocity < 2.4 m/s; cases with TR maximum velocity of 2.4-3.3 m/s were observed in both BV and NBV groups. Receiver-operating-characteristics-curve analysis was performed on the 11 patients in the BV group and five patients in the NBV group with a TR maximum velocity of 2.4-3.3 m/s. dP/dt ≥ 350 mmHg/s and TR maximum velocity ≥ 2.9 m/s were identified as criteria for predicting the outcome in such cases. The performance of dP/dt ≥ 350 mmHg/s in predicting BV after birth in fetuses with TVD or Ebstein's anomaly was higher compared to that of TR maximum velocity ≥ 2.9 m/s (sensitivity, 90.9% vs 72.3% and specificity, 80.0% vs 80.0%, respectively). CONCLUSIONS: In fetuses with TVD or Ebstein's anomaly, the postnatal outcome may be BV or NBV when the TR maximum velocity is 2.4-3.3 m/s. In such cases, by combining the TR maximum velocity with dP/dt ≥ 350 mmHg/s, BV after birth may be predicted with greater accuracy. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Anomalia de Ebstein , Morte Perinatal , Insuficiência da Valva Tricúspide , Criança , Recém-Nascido , Feminino , Humanos , Gravidez , Lactente , Anomalia de Ebstein/diagnóstico por imagem , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/diagnóstico por imagem , Morte Fetal , Feto , Parto , Estudos Retrospectivos
19.
Ultrasound Obstet Gynecol ; 61(1): 49-58, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36350016

RESUMO

OBJECTIVES: Although many studies have supported the efficacy of transplacental treatment for fetal supraventricular tachyarrhythmia, the long-term neurodevelopmental outcome after antenatal antiarrhythmic treatment is not well understood. The aim of this study was to investigate the prognosis and neurodevelopmental outcome at 36 months of corrected age and the incidence of tachyarrhythmia after birth, following protocol-defined antenatal therapy for fetal supraventricular tachyarrhythmia. METHODS: This was a 3-year follow-up study of a multicenter trial that evaluated the efficacy and safety of protocol-defined transplacental treatment for fetal supraventricular tachycardia (SVT) and atrial flutter (AFL). The primary endpoints were mortality and neurodevelopmental impairment (NDI) at 36 months of corrected age. NDI was defined as any of the following outcomes: cerebral palsy, bilateral blindness, bilateral deafness or neurodevelopmental delay. Neurodevelopmental delay was evaluated using appropriate developmental quotient scales, mainly the Kyoto Scale of Psychological Development, or examination by pediatric neurologists. The detection rate of tachyarrhythmia at birth and at 18 and 36 months of corrected age was also evaluated as the secondary endpoint. In addition, the association of NDI at 36 months with perinatal and postnatal factors was analyzed. RESULTS: Of 50 patients enrolled in the original trial, one withdrew consent and in two there was fetal death, leaving 47 patients available for enrollment in this follow-up study. Of these, 45 cases were available for analysis after two infants were lost to follow-up. The mortality rate was 2.2% (1/45) during a median follow-up of 3.2 (range, 2.1-9.4) years. The infant died at the age of 2.1 years. Another infant had missing neurodevelopmental assessment data. In the remaining 43 infants, at 36 months of corrected age, NDI was detected in 9.3% (4/43) overall and in two of three (66.7%) cases with fetal hydrops with subcutaneous edema. Cerebral palsy was noted in two infants with severe subcutaneous edema or ascites at an early gestational age. Neurodevelopmental delay was found in two infants with severe congenital abnormalities (one with tuberous sclerosis and the other with heterotaxy syndrome). Tachyarrhythmia was present in 31.9% (15/47) cases in the neonatal period and decreased to 8.9% (4/45) and 4.5% (2/44) at 18 and 36 months of corrected age, respectively. The median ventricular rate at diagnosis was significantly higher in infants with NDI compared to those without (265 vs 229 bpm; P = 0.003). In infants with NDI, compared to those without, fetal hydrops with subcutaneous edema at diagnosis was more common (50.0% vs 2.6%; P = 0.019) and the duration of fetal effusion was longer (median, 10.5 vs 0 days; P = 0.013). Postnatal arrhythmia and physical development abnormalities were not associated with NDI. CONCLUSIONS: This multicenter 3-year follow-up study is the first to demonstrate the long-term mortality and morbidity of infants born following protocol-defined transplacental treatment for fetal SVT and AFL. NDI was associated with the presence of fetal hydrops with subcutaneous edema at diagnosis and longer duration of fetal effusion. Neurodevelopmental delay was detected only in infants with severe congenital abnormalities. Therefore, in infants that have undergone antenatal treatment for fetal tachyarrhythmia and in which there are no comorbidities, the risk of NDI is low. However, in those with fetal hydrops with subcutaneous edema and/or associated severe congenital abnormalities, the risk for long-term neurologic morbidity might be considered somewhat increased. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Doenças Fetais , Hidropisia Fetal , Lactente , Recém-Nascido , Criança , Humanos , Feminino , Gravidez , Pré-Escolar , Seguimentos , Doenças Fetais/diagnóstico , Arritmias Cardíacas , Taquicardia , Estudos Retrospectivos
20.
Phys Chem Chem Phys ; 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37464810

RESUMO

Li7La3Zr2O12 (LLZO) and related ceramic solid electrolytes feature excellent stability and reasonable ionic conductivity, but processing remains challenging. High-temperature co-sintering is required for successful integration with the electrode, which is energetically costly and can lead to unacceptable cathode degradation. The introduction of dopants can promote lower-temperature processing by improving deformability and disrupting lattice integrity; however, an unbiased, systematic study correlating these properties to the dopant chemistry and composition is lacking. Here, we rely on a set of static and dynamic metrics derived from first-principles simulations to estimate the impact of doping on LLZO processability by quantifying LLZO structural deformability. We considered three distinct dopants (Al, Ba, and Ta) as representatives of substitutional incorporation on Li, La, and Zr sites. Our descriptors indicate that doping in general positively impacts lattice deformability, although significant sensitivities to dopant identity and concentration are observed. Amongst the tested dopants, Al doping (on the Li site) appears to have the greatest impact, as signaled across nearly the entire set of computed features. We suggest that these proxy descriptors, once properly calibrated against well-controlled experiments, could enable the use of first-principles simulations to computationally screen new ceramic electrolyte compositions with improved processability.

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