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1.
Phys Chem Chem Phys ; 26(15): 11910-11921, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38568744

RESUMO

Study of the near-UV photodissociation dynamics for monolayer (ML) quantities of CH3I on thin films of a series of fluorobenzenes and benzene (1-25 ML) grown on a Cu(100) substrate finds that in addition to gas-phase-like neutral photodissociation, CH3I dissociation can be enhanced via electronic energy transfer to the CH3I following photoabsorption in several of the thin films studied. Distinct CH3 photofragment kinetic energy distributions are found for CH3I photodissociation on C6H5F, 1,4-C6H4F2 and C6H6 thin films, and distinguished from neutral photodissociation pathways using polarized incident light. The effective photodissociation cross section for CH3I on these thin films is increased as compared to that for the higher F-count fluorobenzene thin films due to the additional photodissociation pathway available. Quenching by the metal substrate of the photoexcitation via this new pathway suggests a significantly longer timescale for excitation than that of neutral CH3I photodissociation. The observations support a mechanism in which neutral photoexcitation in the thin film (i.e. an exciton) is transported to the interface with CH3I, and transfers the electronic excitation to the CH3I which then dissociates. The unimodal CH3 photofragment distribution and observed kinetic energies on the fluorobenzene thin films suggest that the dissociation occurs via the 3Q1 excited state of CH3I.

2.
J Neuroendocrinol ; 36(3): e13372, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38361341

RESUMO

A good and accessible biomarker is of great clinical value in neuroendocrine tumor (NET) patients, especially considering its frequently indolent nature and long-term follow-up. Plasma chromogranin A (CgA) and 5-hydroxyindoleacetic acid (5-HIAA) are currently used as biomarkers in NET, but their sensitivity and specificity are restricted. 5-HIAA is the main metabolite of serotonin, an important neurotransmitter of the tryptophan pathway. The aim of this study is to estabish a sensitive and accurate method for the quantification of tryptophan pathway metabolites in plasma. We further aimed to evaluate its utility as a clinical tool in NET disease. We obtained plasma samples from NET patients and healthy controls recruited from the University Hospital of North Norway, Tromsø. Samples were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and eight metabolites of the tryptophan pathway were quantified. We included 130 NET patients (72/130 small intestinal [SI] NET, 35/130 pancreatic NET, 23/130 other origin) and 20 healthy controls. In the SI-NET group, 26/72 patients presented with symptoms of carcinoid syndrome (CS). We found that combining tryptophan metabolites into a serotonin/kynurenine pathway ratio improved diagnostic sensitivity (92.3%) and specificity (100%) in detecting CS patients from healthy controls compared with plasma 5-HIAA alone (sensitivity 84.6%/specificity 100%). Further, a clinical marker based on the combination of plasma serotonin, 5-HIAA, and 5OH-tryptophan, increased diagnostic capacity identifying NET patients with metastasized disease from healthy controls compared with singular plasma 5-HIAA, serotonin, or CgA. In addition, this marker was positive in 61% of curatively operated SI-NET patients compared with only 10% of healthy controls (p < .001). Our results indicate that simultaneous quantification of several tryptophan metabolites in plasma, using LC-MS/MS, may represent a clinically useful diagnostic tool in NET disease.


Assuntos
Neoplasias Intestinais , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Neoplasias Gástricas , Triptofano , Humanos , Cromatografia Líquida/métodos , Triptofano/análise , Triptofano/metabolismo , Tumores Neuroendócrinos/diagnóstico , Serotonina/análise , Espectrometria de Massas em Tandem/métodos , Ácido Hidroxi-Indolacético , Biomarcadores
3.
Mycotoxin Res ; 40(1): 1-17, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37953416

RESUMO

Ergot alkaloids are secondary metabolites that are produced by fungi and contaminate cereal crops and grasses. The ergot alkaloids produced by Claviceps purpurea are the most abundant worldwide. The metabolites exist in two configurations, the C-8-R-isomer (R-epimer) and the C-8-S-isomer (S-epimer). These two configurations can interconvert to one another. Ergot alkaloids cause toxic effects after consumption of ergot-contaminated food and feed at various concentrations. For bioactivity reasons, the C-8-R-isomers have been studied to a greater extent than the C-8-S-isomer since the C-8-S-isomers were considered biologically inactive. However, recent studies suggest the contrary. Analytical assessment of ergot alkaloids now includes the C-8-S-isomers and high concentrations of specific C-8-S-isomers have been identified. The inclusion of the C-8-S-isomer in regulatory standards is reviewed. This review has identified that further research into the C-8-S-isomers of ergot alkaloids is warranted. In addition, the inclusion of the C-8-S-isomers into regulatory recommendations worldwide for food and feed should be implemented. The objectives of this review are to provide an overview of historic and current studies that have assessed the C-8-S-isomers. Specifically, this review will compare the C-8-R-isomers to the C-8-S-isomers with an emphasis on the biological activity and analytical assessment.


Assuntos
Claviceps , Alcaloides de Claviceps , Compostos Heterocíclicos de 4 ou mais Anéis
4.
Toxins (Basel) ; 15(8)2023 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-37624254

RESUMO

Ergot sclerotia produce toxic secondary metabolites, ergot alkaloids, that infect cereal crops and grasses. Ergot alkaloids have two isomeric configurations: the C-8-R-isomer (R-epimer), and the C-8-S-isomer (S-epimer). Ergot contaminated matrices, such as cereal grains or grasses, may be stored for extended periods at various temperatures before being analyzed, utilized, or consumed. This study assessed the concentration of six common ergot alkaloids in both configurations found in naturally contaminated wheat over time (one, two, and four months) at different temperatures (room temperature, +4 °C, and -20 °C) using ultra-high-performance liquid chromatography-tandem mass spectrometry. The data indicate that the total ergot concentration within a natural contaminated sample varies over time at room temperature, +4 °C, and -20 °C. The total ergot concentration increased until month two, and decreased at month four, independent of temperature (p < 0.05). The total R-epimer concentration appeared to be less stable over time than the total S-epimer concentration. The changes in the total R and total S-epimer concentrations may have been caused by changes in the ergocristine and ergocristinine concentrations, respectively. Time and temperature should be considered when storing potentially contaminated matrices in a laboratory or practical agriculture situations. Quantification of ergot contaminated matrices should occur prior to their use to ensure the most reliable estimates of the concentration of ergot.


Assuntos
Alcaloides de Claviceps , Temperatura , Agricultura , Cromatografia Líquida de Alta Pressão , Produtos Agrícolas , Grão Comestível , Poaceae
5.
Aust Dent J ; 68(3): 171-178, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37345410

RESUMO

BACKGROUND: Osteoradionecrosis (ORN) is an uncommon and debilitating consequence of head and neck radiotherapy and hyperbaric oxygen therapy (HBOT) has been advocated for prophylaxis prior to performing dentoalveolar procedures. The aim of this study was to evaluate a prophylactic HBOT protocol and describe the outcomes of susceptible individuals. METHODS: A retrospective audit of adults who attended the Oral and Maxillofacial Surgery department at the Royal Adelaide Hospital (South Australia) who received dental extractions with a history of radiotherapy to the jaws from 2008 to 2020. Data including demographic information and outcomes of osteoradionecrosis and delayed healing was recorded. RESULTS: A total of 121 individuals were eligible for case note review; 68.6% of individuals were male and 55.4% were aged over 67 years. Osteoradionecrosis occurred in 9.1% of individuals and delayed healing for 3.3%; fifteen individuals (12.4%) were unable to complete the HBOT protocol. The individuals who were diagnosed with ORN had a significant association with age (P = 0.006) and binary analysis showed alcohol consumption to be a significant predictor. CONCLUSIONS: Prophylactic HBOT protocol had a lower proportion of individuals diagnosed with ORN and those who were diagnosed were more likely to be younger males and have current alcohol consumption.


Assuntos
Neoplasias de Cabeça e Pescoço , Oxigenoterapia Hiperbárica , Osteorradionecrose , Adulto , Humanos , Masculino , Idoso , Feminino , Osteorradionecrose/prevenção & controle , Oxigenoterapia Hiperbárica/métodos , Estudos Retrospectivos , Austrália do Sul , Neoplasias de Cabeça e Pescoço/radioterapia
6.
Anaesthesia ; 78(9): 1102-1111, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37381617

RESUMO

Exposure to opioid analgesics due to surgery increases the risk of new persistent opioid use. A mechanistic hypothesis for opioids' abuse liability rests on the belief that, in addition to pain relief, acute opioid treatment improves well-being (e.g. via euphoria) and relieves anxiety. However, opioids do not consistently improve mood in laboratory studies of healthy non-opioid users. This observational study determined how two commonly used opioid analgesics affected patients' subjective well-being in standard clinical practice. Day surgery patients rated how good and how anxious they felt before and after an open-label infusion of remifentanil (n = 159) or oxycodone (n = 110) in the operating theatre before general anaesthesia. One minute after drug injection, patients reported feeling intoxicated (> 6/10 points). Anxiety was reduced after opioids, but this anxiolytic effect was modest (remifentanil Cohen's d = 0.21; oxycodone d = 0.31). There was moderate to strong evidence against a concurrent improvement in well-being (Bayes factors > 6). After remifentanil, ratings of 'feeling good' were significantly reduced from pre-drug ratings (d = 0.28). After oxycodone, one in three participants felt better than pre-drug. Exploratory ordered logistic regressions revealed a link between previous opioid exposure and opioid effects on well-being, as only 14 of the 80 opioid-naïve patients reported feeling better after opioid injection. The odds of improved well-being ratings after opioids were higher in patients with previous opioid exposure and highest in patients with > 2 weeks previous opioid use (adjusted OR = 4.4). These data suggest that opioid-induced improvement of well-being is infrequent in opioid-naïve patients. We speculate that peri-operative exposure could increase risk of persistent use by rendering subsequent positive opioid effects on well-being more likely.


Assuntos
Analgésicos Opioides , Transtornos Relacionados ao Uso de Opioides , Humanos , Oxicodona/uso terapêutico , Remifentanil , Teorema de Bayes , Transtornos Relacionados ao Uso de Opioides/prevenção & controle
7.
Toxicol Rep ; 10: 604-611, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37213815

RESUMO

Ergot alkaloids are secondary metabolites that exist in two configurations, the C-8-R-isomer (R-epimer), and the C-8-S-isomer (S-epimer). Toxic effects of ergot, such as vasoconstriction, have been primarily attributed to the R-epimer bioactivity, as compared to the S-epimer. Recent studies demonstrated potential bioactivity of S-epimers. Therefore, further cost-effective investigations of the S-epimers are needed. The present study investigated the S-epimer - vascular receptor binding relationship. An in silico molecular docking approach, utilizing AutoDock Vina and DockThor, was used to determine if the S-epimer (ergocristinine) binds to vascular receptors and to compare the binding affinity and interactions to the corresponding R-epimer (ergocristine) and a structural analogue (lysergic acid amide). The binding energy (kcal/mol) of ergocristinine was - 9.7 or - 11.0 to the serotonin (5-HT) 2 A receptor and - 8.7 or - 11.4 to the alpha 2 A adrenergic receptor, depending on the software used. A hydrogen bond was formed between ergocristinine and amino acid residues of the 5-HT 2 A and alpha 2 A adrenergic receptor binding sites, with bond lengths of 3.10 Å and 3.28 Å, respectively. Binding affinities and molecular interactions among the ligands to each receptor differed. Different affinities and interactions may relate to differences in the chemical structures. The binding affinities and strong molecular interactions of the S-epimer to vascular receptors may contribute to the observed physiological manifestations that occur after ergot alkaloid exposure. The results of the present study suggest further investigation on the receptor binding of the S-epimers of ergot alkaloids.

8.
Eur Arch Paediatr Dent ; 24(4): 429-440, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37036643

RESUMO

PURPOSE: A scoping review to describe the use of enzyme replacement therapy (ERT) in the form of asfotase alfa to decrease the severity of oral manifestations in children with hypophosphatasia (HPP). METHODS: Six databases were searched using keywords and index terms related to "hypophosphatasia," "children," and "enzyme replacement therapy." Duplicates were removed and two independent reviewers screened the titles and abstracts to identify articles for full-text review. Extracted data was summarised narratively. RESULTS: The systematic search identified 3548 articles, with 171 suitable for full-text review and a final 22 that met inclusion criteria. Enzyme replacement therapy generally resulted in a reduction in the presence and severity of oral manifestations of HPP. However, numerous studies failed to report specific details regarding the nature of oral health outcomes and there were reported cases of further loss of primary teeth. CONCLUSIONS: The available evidence suggests that that ERT in the form of asfotase alfa for HPP in infants and young children leads to improved oral health outcomes. It is recommended that the outcomes are improved with earlier initiation of ERT. Further, well-designed clinical research is required to assess oral health improvements and decreased morbidity associated with the early loss of teeth.


Assuntos
Hipofosfatasia , Lactente , Criança , Humanos , Pré-Escolar , Hipofosfatasia/tratamento farmacológico , Terapia de Reposição de Enzimas/efeitos adversos , Terapia de Reposição de Enzimas/métodos , Saúde Bucal
9.
Aust Dent J ; 68(2): 92-97, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36811194

RESUMO

BACKGROUND: The Australian Health Practitioner Regulation Agency (AHPRA) requires general dental practitioners (GDPs) to agree to regulatory advertising guidelines on initial registration and annual renewal. The aim of this study was to determine the compliance of GDPs websites to these requirements. METHODS: A representative sample of GDPs websites from each state and territory in Australia was based on the total AHPRA registrant distribution. Assessment of compliance was used across five domains consisting of 17 criteria related to AHPRA's advertising of regulated health services guidelines, as well as section 133 of the National Law. Inter-rater reliability was estimated using Fleiss's Kappa. RESULTS: One hundred and ninety-two GDPs websites were reviewed with 85% non-compliant with at least one of the legal and regulatory requirements relating to advertising. Of these websites, 52% displayed false and misleading information, 12.8% had offers and inducement without clear terms and conditions, 11.5% used written testimonials, 33.9% created unrealistic expectation of benefit and 39.6% encouraged indiscriminate and unnecessary use of health services. CONCLUSIONS: More than 85% of GDP websites in Australia did not comply with legal and regulatory requirements related to advertising. A multi-stakeholder approach involving AHPRA, professional dental bodies and dental registrants is necessary to improve compliance.


Assuntos
Publicidade , Odontólogos , Humanos , Austrália , Reprodutibilidade dos Testes , Papel Profissional , Odontologia Geral
10.
Sci Total Environ ; 861: 160679, 2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36481156

RESUMO

Management of metal(loid) tailings at historic sites presents environmental hazards usually requiring rehabilitation to mitigate pollution risks. Strategies employed include capping or establishing vegetation directly, which requires tailings assessments to determine suitable rehabilitation approaches. Assessments are typically geochemical analyses, but plant based approaches may provide a more accurate measure of revegetation success although they are often limited to germination indices. This study uses the plant bioassay (Rhizotest™) with common geochemical assessment to predict plant uptake of metal(loid)s and the subsequent likely rehabilitation success. Pb/Zn tailings from five legacy sites within the UK and Ireland were characterized for pH, EC, water soluble and CaCl2-extractable content and aqua regia extractable content. Uptake of Sb, As, Cd, Cu, Ca, Mg, Mn, Zn, Pb was determined in shoots and roots of Lolium perenne. Total Zn, Pb, Sb, Cd and As in tailings ranged from 694 to 2683 mg kg-1, 1252 to 8072 mg kg-1, 14 to 148 mg kg-1, 1.3 to 44 mg kg-1 and 1.3 to 45 mg kg-1, respectively. The only correlation found between total and water soluble or CaCl2-extractable metal(loid) contents was for Cd, where r = 0.8 for total and CaCl2-extractable fractions. Limited uptake and translocation risk was identified for major contaminants Zn and Pb in most tailings samples but in some cases exceedance of phytotoxic threshold values occurred that was not reflected in geochemical analysis. Crucially, although total Cd and Sb content was relatively low (< 20 mg kg-1) in some tailings, elevated plant content for some samples highlights phytotoxic risk from minor elements. Results indicate that screening based on geochemical content is not sufficiently predictive of metal(loid) phytoavailability to reliably inform mine rehabilitation strategies. We therefore strongly recommend that geochemical analyses are supplemented with plant based bioassay to plan mine tailings revegetation and reduce risk of wider ecosystem metal(loid) transfer.


Assuntos
Metais Pesados , Poluentes do Solo , Ecossistema , Cádmio/análise , Cloreto de Cálcio , Chumbo , Plantas , Bioensaio , Poluentes do Solo/análise
11.
Eur Arch Paediatr Dent ; 24(1): 117-123, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36348176

RESUMO

PURPOSE: Systemic diseases or drugs administered early in life may cause a disruption in amelogenesis and contribute to the qualitative defect of enamel described as molar-incisor hypomineralisation (MIH). Therefore, an increase in prevalence of MIH in children with type 1 diabetes (T1D) may be expected as this systemic disorder is commonly diagnosed in early childhood. The aim of this study was to determine the prevalence of MIH in a cohort of children with T1D and investigate diagnosis of MIH with T1D factors. METHODS: Cross-sectional study of children with T1D recruited from paediatric diabetes clinics at the Women's and Children's Hospital (South Australia). A detailed medical history, comprehensive dental and MIH examination according to the European Academy of Paediatric Dentistry (EAPD) long form classification was collected for each child. All upper and lower first permanent molars and central incisors were scored. RESULTS: A total number of 73 participants; 35 (47.95%) males were examined including 584 teeth. The mean age of the participants was 13.25 ± 2.58 years, with a mean age of diagnosis 7.75 ± 3.58 years, and a mean HbA1c of 8.5 ± 1.6%. 42 out of 73 children (54.8%) had enamel defects on at least one of the teeth examined. However, 19.2% met the criteria for MIH. Univariate and bivariate analyses were conducted but no significant associations were noted between MIH and risk factors including diabetes control (p > 0.1). CONCLUSION: There was a high prevalence of enamel defects and MIH amongst children with T1D. More research is required to establish association between T1D and MIH.


Assuntos
Hipoplasia do Esmalte Dentário , Diabetes Mellitus Tipo 1 , Hipomineralização Molar , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Austrália/epidemiologia , Estudos Transversais , Hipoplasia do Esmalte Dentário/epidemiologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/epidemiologia , Dente Molar , Hipomineralização Molar/epidemiologia , Prevalência
12.
J Public Health (Oxf) ; 45(2): e266-e274, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-36321614

RESUMO

BACKGROUND: Screening options for pancreatic ductal adenocarcinoma (PDAC) are limited. New-onset type 2 diabetes (NoD) is associated with subsequent diagnosis of PDAC in observational studies and may afford an opportunity for PDAC screening. We evaluated this association using a large administrative database. METHODS: Patients were identified using claims data from the OptumLabs® Data Warehouse. Adult patients with NoD diagnosis were matched 1:3 with patients without NoD using age, sex and chronic obstructive pulmonary disease (COPD) status. The event of PDAC diagnosis was compared between cohorts using the Kaplan-Meier method. Factors associated with PDAC diagnosis were evaluated with Cox's proportional hazards modeling. RESULTS: We identified 640 421 patients with NoD and included 1 921 263 controls. At 3 years, significantly more PDAC events were identified in the NoD group vs control group (579 vs 505; P < 0.001). When controlling for patient factors, NoD was significantly associated with elevated risk of PDAC (HR 3.474, 95% CI 3.082-3.920, P < 0.001). Other factors significantly associated with PDAC diagnosis were increasing age, increasing age among Black patients, and COPD diagnosis (P ≤ 0.05). CONCLUSIONS: NoD was independently associated with subsequent diagnosis of PDAC within 3 years. Future studies should evaluate the feasibility and benefit of PDAC screening in patients with NoD.


Assuntos
Carcinoma Ductal Pancreático , Diabetes Mellitus Tipo 2 , Neoplasias Pancreáticas , Adulto , Humanos , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/complicações , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/epidemiologia , Carcinoma Ductal Pancreático/complicações , Estudos Retrospectivos , Neoplasias Pancreáticas
13.
J Anim Sci ; 100(9)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35775420

RESUMO

Vasoconstriction is a known effect associated with ergot alkaloid consumption. The vascular contractile responses are often sustained for an extended period after exposure. Ergot alkaloids exist in two molecular configurations, the C-8-(R)-isomer (R-epimer) and the C-8-(S)-isomer (S-epimer). The sustained vascular contractile response to the R-epimers has been studied previously, unlike the S-epimers which are thought to be biologically inactive. Additionally, antagonists have been utilized to attenuate the vascular contraction associated with the R-epimers of ergot alkaloids utilizing ex vivo techniques. This study utilized an arterial tissue bath to examine and compare the sustained vascular contractile response attributed to ergocristine (R) and ergocristinine (S) using dissected bovine metatarsal arteries. The contractile blocking effect of a noncompetitive alpha-adrenergic antagonist, phenoxybenzamine (POB), was also investigated in precontracted arteries. Arteries (n = 6/epimer) were exposed to a single dose of ergocristine or ergocristinine (1 × 10-6 M in buffer). Each of the epimer doses was followed by a POB (1 × 10-3 M) or methanol (control) treatment at 90 min and the response was observed for another 90 min. Both epimers produced a sustained contractile response over the 180-min incubation period in the control groups. The R-epimer caused a greater sustained contractile response from 60 to 180 min post epimer exposure, compared to the S-epimer (P < 0.05, generalized estimating equations, independent t-test). Phenoxybenzamine caused a decrease in the contractile response induced by ergocristine and ergocristinine from 105 to 180 min, compared to the control (P < 0.05, generalized estimating equations, paired t-test). Overall, these results demonstrate the presence of a sustained vascular contractile response attributed to the R- and S-epimer of an ergot alkaloid with differences in contractile response between the epimers, suggesting differences in receptor binding mechanisms. Furthermore, this study demonstrated that a noncompetitive antagonist could attenuate the sustained arterial contractile effects of both ergot configurations ex vivo. Additional investigation into S-epimers of ergot alkaloids is needed. This research contributes to the understanding of the ergot epimer-vascular receptor binding mechanisms, which may support the investigation of different approaches of minimizing ergot toxicity in livestock.


Ergot alkaloids cause blood vessels to contract when contaminated feed is consumed by animals. Vascular contraction often remains for a prolonged period and involves the binding of ergot to specific receptors in the blood vessels. This study assessed and compared the sustained contraction of cow arteries after exposure to two forms of an ergot alkaloid, namely, ergocristine and ergocristinine. The effects of a specific receptor blocker, phenoxybenzamine, on the vascular contraction induced by these forms were also examined. This study showed that both forms of ergot caused a sustained contraction of cow arteries but to different magnitudes. Differences in contraction could be related to differences in how each form of ergot binds to receptors. The receptor blocker decreased the sustained contractile response of both forms of ergot. Further understanding of how the different forms of ergot bind to receptors, and how to decrease the adverse effects, may help mitigate the toxic effects of ergotism.


Assuntos
Alcaloides de Claviceps , Metanol , Animais , Bovinos , Ergolinas , Alcaloides de Claviceps/química , Fenoxibenzamina
14.
J Agric Food Chem ; 70(29): 8931-8941, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35830571

RESUMO

Detoxification of ergot-contaminated feed by ammonia would be a practical application, given that ammonia is routinely used in the agriculture industry. To assess the effects of ammonia on ergot alkaloids, natural ergot-contaminated wheat was ammoniated. The total concentration of ergot alkaloids (R- and S-epimers) decreased after exposure to ammonia (8-29%). Separately, the total R-epimers decreased in concentration (40-66%), whereas the total S-epimers increased (21-81%). Specific ergot alkaloids demonstrated degradation and/or epimerization after exposure to ammonia, potentially associated with structural differences, and influenced the total concentrations observed. Ammonization of ergot standards resulted in potential degradation products and epimerization, supporting the above results. The use of ultrahigh-performance liquid chromatography-tandem mass spectrometry provides an updated assessment of the detoxification potential of ammonia for ergot alkaloids and the quantification of the S-epimers. Ammonia alters the R- and S-epimers of ergot alkaloids, which may lead to a potential practical detoxification process of ergot-contaminated feed.


Assuntos
Claviceps , Alcaloides de Claviceps , Amônia , Cromatografia Líquida de Alta Pressão/métodos , Alcaloides de Claviceps/análise , Contaminação de Alimentos/análise , Compostos Heterocíclicos de 4 ou mais Anéis , Triticum/química
15.
J Neonatal Perinatal Med ; 15(1): 55-62, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34657851

RESUMO

BACKGROUND: Timely development of early motor skills is essential for later skill development in multiple domains. Infants with severe bronchopulmonary dysplasia (BPD) have significant risk for developmental delays. Early motor skill development in this population has not been described. The aim of the present study was to characterize motor skill acquisition at 3 and 6 months corrected age (CA) and assess trajectories of skill development over this time period in infants with severe BPD. METHODS: We performed a single-center, retrospective descriptive study. Motor skills were categorized as present and normal, present but atypical, or absent at 3 and 6 months CA. Logistic regression was used to identify clinical characteristics associated with negative trajectories of skill acquisition. RESULTS: Data were available for 232 infants and 187 infants at 3 and 6 months CA, respectively. Ten motor skills were present and normal in 5-44%(range) of subjects at 3 months. Nineteen motor skills were present and normal in 1-63%(range) of subjects at 6 months. Significant postural asymmetry was noted throughout the study period. Loss of skills and worsening asymmetries over time were common. Exposure to sedating medications was significantly associated with poor development. CONCLUSION: We report delays in motor skill acquisition and postural asymmetries in infants with severe BPD at both 3 and 6 months CA. The association between sedating medications and poor development suggests that efforts to limit these exposures may lead to improved development. Targeted interventions to facilitate early motor development may improve outcomes of this high-risk population.


Assuntos
Displasia Broncopulmonar , Displasia Broncopulmonar/epidemiologia , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Modelos Logísticos , Estudos Retrospectivos , Fatores de Risco
16.
Ann Oncol ; 33(2): 204-215, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34710571

RESUMO

BACKGROUND: Antitumor activity of ipilimumab or BRAF ± MEK inhibitors (BRAFi ± MEKi) following pembrolizumab administration in melanoma is poorly characterized. PATIENTS AND METHODS: In the phase III KEYNOTE-006 study, patients with unresectable stage III/IV melanoma received pembrolizumab (10 mg/kg) once every 2 or 3 weeks (Q3W) or ipilimumab (3 mg/kg) Q3W. The current post hoc analysis evaluates outcomes with ipilimumab or BRAFi ± MEKi as first subsequent systemic therapy after pembrolizumab administration and includes patients who completed or discontinued pembrolizumab after one or more dose. Pembrolizumab arms were pooled. RESULTS: At data cut-off (4 December 2017), median follow-up was 46.9 months. Of 555 pembrolizumab-treated patients, first subsequent therapy was ipilimumab for 103 (18.6%) and BRAFi ± MEKi for 59 (10.6%) [33 received BRAFi + MEKi, 26 BRAFi alone; 37 (62.7%) were BRAFi ± MEKi naïve]. In the subsequent ipilimumab group, ORR with previous pembrolizumab was 17.5% [1 complete response (CR); 17 partial response (PR)]; 79.6% had discontinued pembrolizumab due to progressive disease (PD); median overall survival (OS) was 21.5 months. ORR with subsequent ipilimumab was 15.5%; 11/16 responses (8 CRs; 3 PRs) were ongoing. ORR with subsequent ipilimumab was 9.7% for patients with PD as best response to pembrolizumab. Median OS from ipilimumab initiation was 9.8 months. In the subsequent BRAFi ± MEKi group, ORR with previous pembrolizumab was 13.5% (8 PR); 76.3% had discontinued pembrolizumab due to PD; median OS was 17.9 months. ORR with subsequent BRAFi ± MEKi was 30.5%, 7/18 responses (4 CR, 3 PR) were ongoing. Median OS from BRAFi ± MEKi initiation was 12.9 months. ORR for BRAFi ± MEKi-naïve patients who received subsequent BRAFi ± MEKi was 43.2%; 6/16 were ongoing (3 CR, 3 PR). CONCLUSIONS: Ipilimumab and BRAFi ± MEKi have antitumor activity as first subsequent therapy after pembrolizumab in patients with advanced melanoma.


Assuntos
Melanoma , Proteínas Proto-Oncogênicas B-raf , Anticorpos Monoclonais Humanizados , Humanos , Ipilimumab/efeitos adversos , Melanoma/patologia , Quinases de Proteína Quinase Ativadas por Mitógeno/uso terapêutico
17.
BMC Womens Health ; 21(1): 347, 2021 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-34602062

RESUMO

BACKGROUND: Retained products of conception (POC) following uterine evacuation can lead to adverse sequelae, including hemorrhage, endometritis, intrauterine adhesions, and reoperation. Use of procedural transvaginal sonography (TVUS) in the operating room has been proposed to help decrease retained POC. METHODS: A retrospective review of all first trimester uterine evacuation procedures from 1/2015 to 2/2017 was performed, noting use of transabdominal ultrasonography, retained products of conception, and complications. A practice change was implemented in May 2018, in which routine intra-procedural TVUS use was initiated. A second retrospective chart review was conducted to assess for post-implementation incidence of retained POC, re-operation, and associated complications. RESULTS: Prior to intra-procedural TVUS implementation, 130 eligible procedures were performed during the specified timeframe, with 9/130 (6.9%) incidence of retained products of conception. TAUS was performed in 59/130 (45.4%) of procedures, and 4/9 (44.4%) of those with retained products. There were eight re-operative procedures in seven patients, and two patients were treated with misoprostol. Complications included hemorrhage, Asherman's syndrome and endometritis. Following implementation, 95 first trimester procedures were performed with transvaginal sonography, with 0 (0%) cases of retained POC (p = 0.01), no incidences of re-operation (p = 0.02), and one case of Asherman's syndrome. TVUS findings led to additional focused suction curettage in 20/95 (21.0%) of procedures. The endometrium was measured on procedure completion in 64 procedures, with a mean thickness of 5.5 mm (1-12 mm). CONCLUSION: Implementation of routine TVUS during uterine evacuation may reduce the incidence of retained POC and associated reoperation rates. Further multi-center trials are needed to confirm this finding.


Assuntos
Melhoria de Qualidade , Curetagem a Vácuo , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Estudos Retrospectivos , Ultrassonografia
18.
Nutrients ; 13(7)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34371916

RESUMO

White adipose tissue (WAT) is a dynamic endocrine organ that can play a significant role in thermoregulation. WAT has the capacity to adopt structural and functional characteristics of the more metabolically active brown adipose tissue (BAT) and contribute to non-shivering thermogenesis under specific stimuli. Non-shivering thermogenesis was previously thought to be uncoupling protein 1 (UCP1)-dependent however, recent evidence suggests that UCP1-independent mechanisms of thermogenesis exist. Namely, futile creatine cycling has been identified as a contributor to WAT thermogenesis. The purpose of this study was to examine the efficacy of creatine supplementation to alter mitochondrial markers as well as adipocyte size and multilocularity in inguinal (iWAT), gonadal (gWAT), and BAT. Thirty-two male and female Sprague-Dawley rats were treated with varying doses (0 g/L, 2.5 g/L, 5 g/L, and 10 g/L) of creatine monohydrate for 8 weeks. We demonstrate that mitochondrial markers respond in a sex and depot specific manner. In iWAT, female rats displayed significant increases in COXIV, PDH-E1alpha, and cytochrome C protein content. Male rats exhibited gWAT specific increases in COXIV and PDH-E1alpha protein content. This study supports creatine supplementation as a potential method of UCP1-independant thermogenesis and highlights the importance of taking a sex-specific approach when examining the efficacy of browning therapeutics in future research.


Assuntos
Tecido Adiposo Branco/efeitos dos fármacos , Regulação da Temperatura Corporal/efeitos dos fármacos , Creatina/farmacologia , Suplementos Nutricionais , Mitocôndrias/efeitos dos fármacos , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Citocromos c/metabolismo , Relação Dose-Resposta a Droga , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Masculino , Mitocôndrias/metabolismo , Piruvato Desidrogenase (Lipoamida) , Ratos Sprague-Dawley , Fatores Sexuais , Proteína Desacopladora 1/metabolismo
19.
Geochem Geophys Geosyst ; 22(7): e2021GC009743, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34434077

RESUMO

Tectonic pseudotachylytes are thought to be unique to certain water-deficient seismogenic environments and their presence is considered to be rare in the geological record. Here, we present field and experimental evidence that frictional melting can occur in hydrothermal fluid-rich faults hosted in the continental crust. Pseudotachylytes were found in the >40 km-long Bolfín Fault Zone of the Atacama Fault System, within two ca. 1 m-thick (ultra)cataclastic strands hosted in a damage-zone made of chlorite-epidote-rich hydrothermally altered tonalite. This alteration state indicates that hydrothermal fluids were active during the fault development. Pseudotachylytes, characterized by presenting amygdales, cut and are cut by chlorite-, epidote- and calcite-bearing veins. In turn, crosscutting relationship with the hydrothermal veins indicates pseudotachylytes were formed during this period of fluid activity. Rotary shear experiments conducted on bare surfaces of hydrothermally altered rocks at seismic slip velocities (3 m s-1) resulted in the production of vesiculated pseudotachylytes both at dry and water-pressurized conditions, with melt lubrication as the primary mechanism for fault dynamic weakening. The presented evidence challenges the common hypothesis that pseudotachylytes are limited to fluid-deficient environments, and gives insights into the ancient seismic activity of the system. Both field observations and experimental evidence, indicate that pseudotachylytes may easily be produced in hydrothermal environments, and could be a common co-seismic fault product. Consequently, melt lubrication could be considered one of the most efficient seismic dynamic weakening mechanisms in crystalline basement rocks of the continental crust.

20.
Osteoporos Int ; 32(12): 2433-2448, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34169346

RESUMO

Individuals with low socio-economic status (SES) have a more than 25% higher risk of fragility fractures than individuals with high SES. Body mass index and lifestyle appear to mediate the effect of SES on fracture risk. Strategies to prevent fractures should aim to reduce unhealthy behaviours through tackling structural inequalities. INTRODUCTION: This systematic review and meta-analysis aimed to evaluate the impact of socio-economic status (SES) on fragility fracture risk. METHODS: Medline, Embase, and CINAHL databases were searched from inception to 28 April 2021 for studies reporting an association between SES and fragility fracture risk among individuals aged ≥50 years. Risk ratios (RR) were combined in meta-analyses using random restricted maximum likelihood models, for individual-based (education, income, occupation, cohabitation) and area-based (Index of Multiple Deprivation, area income) SES measures. RESULTS: A total of 61 studies from 26 different countries including more than 19 million individuals were included. Individual-based low SES was associated with an increased risk of fragility fracture (RR 1.27 [95% CI 1.12, 1.44]), whilst no clear association was seen when area-based measures were used (RR 1.08 [0.91, 1.30]). The strength of associations was influenced by the type and number of covariates included in statistical models: RR 2.69 [1.60, 4.53] for individual-based studies adjusting for age, sex and BMI, compared with RR 1.06 [0.92, 1.22] when also adjusted for health behaviours (smoking, alcohol, and physical activity). Overall, the quality of the evidence was moderate. CONCLUSION: Our results show that low SES, measured at the individual level, is a risk factor for fragility fracture. Low BMI and unhealthy behaviours are important mediators of the effect of SES on fracture risk. Strategies to prevent fractures and reduce unhealthy behaviours should aim to tackle structural inequalities in society thereby reducing health inequalities in fragility fracture incidence.


Assuntos
Fraturas Ósseas , Classe Social , Exercício Físico , Humanos , Renda , Estilo de Vida , Fatores Socioeconômicos
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