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1.
Artigo em Inglês | MEDLINE | ID: mdl-39234690

RESUMO

BACKGROUND: Familial chylomicronemia syndrome (FCS) is a rare autosomal recessive disorder. This study aimed to study the genotype distribution of FCS-causing genes in the United Kingdom, genotype-phenotype correlation, and clinical differences between FCS and multifactorial chylomicronemia syndrome (MCS). METHODS: The study included 154 patients (FCS, 74; MCS, 80) from the UK FCS national registry and the UK arm of the FCS International Quality Improvement and Service Evaluation Project. RESULTS: FCS was relatively common in non-Europeans and those with parental consanguinity (P<0.001 for both). LPL variants were more common in European patients with FCS (European, 64%; non-European, 46%), while the genotype was more diverse in non-European patients with FCS. Patients with FCS had a higher incidence compared with patients with MCS of acute pancreatitis (84% versus 60%; P=0.001), recurrent pancreatitis (92% versus 63%; P<0.001), unexplained abdominal pain (84% versus 52%; P<0.001), earlier age of onset (median [interquartile range]) of symptoms (15.0 [5.5-26.5] versus 34.0 [25.2-41.7] years; P<0.001), and of acute pancreatitis (24.0 [10.7-31.0] versus 33.5 [26.0-42.5] years; P<0.001). Adverse cardiometabolic features and their co-occurrence was more common in individuals with MCS compared with those with FCS (P<0.001 for each). Atherosclerotic cardiovascular disease was more prevalent in individuals with MCS than those with FCS (P=0.04). However, this association became nonsignificant after adjusting for age, sex, and body mass index. The prevalence of pancreatic complications and cardiometabolic profile of variant-positive MCS was intermediate between FCS and variant-negative MCS. CONCLUSIONS: The frequency of gene variant distribution varies based on the ethnic origin of patients with FCS. Patients with FCS are at a higher risk of pancreatic complications while the prevalence of atherosclerotic cardiovascular disease is lower in FCS compared with MCS. Carriers of heterozygous pathogenic variants have an intermediate phenotype between FCS and variant-negative MCS.

2.
Foot (Edinb) ; 61: 102130, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39255572

RESUMO

The Scarf osteotomy involves inherent risks and technical challenges. The short scarf osteotomy with single screw fixation has emerged as an alternative approach. This study aims to evaluate the patient-reported outcome measures (PROMs), radiological outcomes, and complications associated with the short scarf osteotomy fixed with a single screw for hallux valgus correction. A prospective cohort study was conducted between October 2018 and October 2023 at a single center, encompassing 271 osteotomies. PROMs were collected prospectively preoperatively and at various postoperative intervals. Radiographic data, including hallux valgus angle (HVA) and intermetatarsal angle (IMA), were measured preoperatively and six weeks postoperatively. Complications were also documented. Statistically significant improvements were observed in all PROMs and were sustained up to 24 months postoperatively. The Visual Analog Scale (VAS) pain score demonstrated a significant reduction from 46.97 at baseline to 12.52 at 24 months (p < 0.001). Likewise, the EQ-5D score improved notably from 0.73 preoperatively to 0.81 at 24 months (p = 0.002). Analysis of the Manchester-Oxford Foot Questionnaire (MOXFQ) revealed substantial improvements across its pain, walking/standing, and social interaction domains over the same period, with all changes showing statistical significance (all p < 0.001). Radiographically, the mean HVA improved significantly from 31.33° preoperatively to 13.33° postoperatively (p < 0.001). Similarly, the mean IMA improved significantly from 14.67° to 7.66° (p < 0.001). The most common complication was superficial wound infection, effectively managed with oral antibiotics. The were no cases of avascular necrosis or fracture. In conclusion, the short Scarf osteotomy fixed with a single screw demonstrates favorable outcomes. These findings support its efficacy and safety as a treatment option, with potential advantages over the conventional technique. Further prospective studies are warranted to validate these findings.

3.
Mar Pollut Bull ; 206: 116781, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39096867

RESUMO

Effective management of Harmful Algal Blooms (HABs) requires understanding factors influencing their occurrence. This study explores these dynamics in the Pengxi River, a tributary of the Three Gorges Reservoir, focusing on nutrient stratification and algal blooms. We hypothesized that nutrient levels in eutrophic waters with stable stratification correlate with HAB magnitude and that disruption of stratification triggers blooms due to nutrient shifts. A 38-day sampling campaign in Gaoyang Lake (April 16-May 23, 2022) revealed that consistent weather between April 26 and May 16 led to a surface density layer, restricting nutrient transfer and causing a bloom with 173.0 µg L-1 Chl-a on May 1. After a heavy rain on May 18, a peak bloom on May 20, dominated by Ceratium hirundinella, showed 533 µg L-1 Chl-a. There was a significant negative correlation between Cyanobacteria and C. hirundinella biomasses (r = -0.296, P < 0.01), highlighting nutrient availability and physical stability's roles in regulating HABs.


Assuntos
Cianobactérias , Monitoramento Ambiental , Proliferação Nociva de Algas , Lagos , Lagos/química , China , Rios/química , Biomassa , Eutrofização
4.
Cureus ; 16(6): e61850, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38975364

RESUMO

Hallux interphalangeal joint (IPJ) flexion contracture is an uncommon deformity with various underlying causes, including trauma, neurological disorders, and connective tissue pathologies. We present a unique case of a 10-year-old female patient with neurofibromatosis type 1 (NF1) and a history of fibula transposition surgery, resulting in a hallux IPJ flexion contracture. We believe that the loss of the proximal fibular attachment of the extensor hallucis longus (EHL) following fibula harvesting resulted in EHL weakness and unopposed flexor hallucis longus (FHL) pull that eventually led to the contracture. The patient underwent various diagnostic assessments, ruling out other potential causes of the deformity. This case emphasizes the importance of considering previous surgical interventions when encountering flexion contractures of the toes.

7.
J Hazard Mater ; 475: 134890, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38876023

RESUMO

There is considerable inconsistency in results pertaining to the biomagnification of PAHs in aquatic systems. Zooplankton specifically play an important role controlling the fate and distribution of organic contaminants up the food chain, particularly in large plateau reservoirs. However, it remains largely unknown how secondary factors affect the magnification of organic compounds in zooplankton. The present study assessed plankton species and nutrients affecting the trophic transfer of PAHs through the micro-food chain in plateau reservoirs, Guizhou Province China. Results show soluble ∑PAHs range from 99.9 - 147.3 ng L-1, and concentrations of ∑PAHs in zooplankton range from 1003.2 - 22441.3, with a mean of 4460.7 ng g-1 dw. Trophic magnification factors (TMFs) > 1 show biomagnifications of PAHs from phytoplankton to zooplankton. The main mechanisms for trophic magnification > 1 are 1) small Copepoda, Cladocera and Rotifera are prey for larger N. schmackeri and P. tunguidus, and 2) the δ15N and TLs of zooplankton are increasing with the increasing nutrients TN, NO3- and CODMn. As a result, log PAHs concentrations in zooplankton are positively correlated with the trophic levels (TLs) of zooplankton, and log BAFs of the PAHs in zooplankton are increasing with increasing TLs and log Kow. Temperature further enhances TMFs and biomagnifications of PAHs as noted by temperature related reductions in δ15N. There are also available soluble PAHs in the water column which are assimilated with increasing phytoplankton biomass within the taxa groups, diatoms, dinoflagellates and chlorophytes. Notable TMFs of PAHs in zooplankton in Guizhou plateau reservoirs are not significantly affected by phytoplankton and zooplankton biomass dilutions. The present study demonstrates the important roles of species selection, nutrients and temperature in the environmental fate of PAHs in freshwaters.


Assuntos
Cadeia Alimentar , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Zooplâncton , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , China , Animais , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo , Zooplâncton/metabolismo , Monitoramento Ambiental , Fitoplâncton/metabolismo , Nutrientes/análise , Nutrientes/metabolismo , Plâncton/metabolismo
8.
Atherosclerosis ; 391: 117476, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38447437

RESUMO

BACKGROUND AND AIMS: Prognosis and management differ between familial chylomicronaemia syndrome (FCS), a rare autosomal recessive disorder, and multifactorial chylomicronaemia syndrome (MCS) or severe mixed hyperlipidaemia. A clinical scoring tool to differentiate these conditions has been devised but not been validated in other populations. The objective of this study was to validate this score in the UK population and identify any additional factors that might improve it. METHODS: A retrospective validation study was conducted using data from 151 patients comprising 75 FCS and 76 MCS patients. All participants had undergone genetic testing for genes implicated in FCS. Validation was performed by standard methods. Additional variables were identified from clinical data by logistic regression analysis. RESULTS: At the recommended FCS score threshold ≥10 points, the sensitivity and specificity of the score in the UK population were 96% and 75%, respectively. The receiver operating characteristic (ROC) curve analysis yielded an area under the curve (AUC) of 0.88 (95% CI 0.83-0.94, p < 0.001). This study identified non-European (predominantly South Asian) ethnicity, parental consanguinity, body mass index (BMI) < 25 kg/m2, and recurrent pancreatitis as additional positive predictors, while BMI >30 kg/m2 was found to be a negative predictor for FCS. However, inclusion of additional FCS predictors had no significant impact on performance of standard FCS score. CONCLUSIONS: Our study validates the FCS score in the UK population to distinguish FCS from MCS. While additional FCS predictors were identified, they did not improve further the score diagnostic performance.


Assuntos
Hiperlipoproteinemia Tipo I , Humanos , Estudos Retrospectivos , Hiperlipoproteinemia Tipo I/diagnóstico , Hiperlipoproteinemia Tipo I/genética , Sensibilidade e Especificidade , Curva ROC , Reino Unido/epidemiologia
9.
J Hazard Mater ; 468: 133787, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38364579

RESUMO

Bioadsorption, bioaccumulation and biodegradation processes in algae, play an important role in the biomagnification of antibiotics, or other organic pollutants, in aquatic food chains. In this study, the bioadsorption, bioaccumulation and biodegradation of norfloxacin [NFX], sulfamethazine [SMZ] and roxithromycin [RTM]) is investigated using a series of culture experiments. Chlorella vulgaris was exposed to these antibiotics with incubation periods of 24, 72, 120 and 168 h. Results show the bioadsorption concentration of antibiotics in extracellular matter increases with increasing alkaline phosphatase activity (AKP/ALP). The bioaccumulation concentrations of NFX, SMZ and RTM within cells significantly increase after early exposure, and subsequently decrease. There is a significant positive antibiotics correlation to superoxide dismutase (SOD), the photosynthetic electron transport rate (ETR) and maximum fluorescence after dark adaptation (Fv/Fm), while showing a negative correlation to malondialdehyde (MDA). The biodegradation percentages (Pb) of NFX, SMZ and RTM range from 39.3 - 97.2, 41.3 - 90.5, and 9.3 - 99.9, respectively, and significantly increase with increasing Fv/Fm, density and chlorophyll-a. The accumulation of antibiotics in extracellular and intracellular substances of C. vulgaris is affected by antibiotic biodegradation processes associated with cell physiological state. The results succinctly explain relationships between algal growth during antibiotics exposure and the bioadsorption and bioaccumulation of these antibiotics in cell walls and cell matter. The findings draw an insightful understanding of the accumulation of antibiotics in algae and provide a scientific basis for the better utilization of algae treatment technology in antibiotic contaminated wastewaters. Under low dose exposures, the biomagnification of antibiotics in algae is affected by bioadsorption, bioaccumulation and biodegradation.


Assuntos
Chlorella vulgaris , Roxitromicina , Poluentes Químicos da Água , Antibacterianos/metabolismo , Chlorella vulgaris/metabolismo , Bioacumulação , Poluentes Químicos da Água/análise , Biodegradação Ambiental , Norfloxacino , Roxitromicina/metabolismo
10.
Ulster Med J ; 92(3): 157-166, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38292502

RESUMO

The effects of 'stress' within the healthcare professions are wide-reaching, not least of all within the field of simulation-based healthcare education. Whilst this popular method of experiential learning offers a 'safe space' for participants to develop their skillset, it also has a more surreptitious action; namely, the incubation of simulation-related stress. Currently, research concerning the complex relationship between stress, learning, and performance is ambiguous, leaving fertile ground for simulationists to debate what level of stress is appropriate for an optimised educational experience. In this narrative review, we examine the human response to stress and outline the various methods that have been used by researchers to measure stress in a quantifiable and standardised way. We then provide a brief overview of simulation-based healthcare education before describing why stress responses have been of interest to healthcare educationalists for some time. Finally, we outline how simulation education environments might provide an ideal environment for studying the human response to stress generally, with ramifications extending beyond the field of medical education.


Assuntos
Educação Médica , Aprendizagem , Humanos , Aprendizagem Baseada em Problemas , Educação Médica/métodos , Atenção à Saúde , Pessoal de Saúde/educação
11.
Environ Pollut ; 344: 123307, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38190877

RESUMO

Soot is a prevalent aerosol found both indoors and outdoors that has several sources, such as natural (e.g., wildfires), civilian (e.g., cooking), or military (e.g., burn pit operation). Additionally, within the sources, factors that influence the physicochemical properties of the soot include combustion temperature, oxygen availability, and fuel type. Being able to reproduce soot in the laboratory and systematically assess its toxicity is important in the pursuit of elucidating pathologies associated with its exposure. Of the organs of interest, we targeted the eye given the scant attention received. Yet, air pollution constituents such as soot have been linked to diseases such as age-related macular degeneration and proliferative vitreoretinopathy. We developed a bench-scale system to synthesize different types of soot, that is, soot with a systematically varied physical attributes or chemical composition. We used common analytical techniques to probe such properties, and used statistical analyses to correlate them with toxicity in vitro using ARPE-19 cells. Within the range of flame conditions studied, we find that soot toxicity increases with increasing oxygen concentration in fuel-rich premixed flames, and weakly increases with decreasing flame temperature. Additionally, soot particles produced in premixed flames are generally smaller in size, exhibit a lesser fractal structure, and are considerably more toxic to ARPE-19 cells than soot particles produced in non-premixed flames.


Assuntos
Oxigênio , Fuligem , Fuligem/análise , Oxigênio/análise , Temperatura
12.
Infect Dis Ther ; 13(1): 57-78, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38103161

RESUMO

INTRODUCTION: ReCOV is a recombinant protein vaccine that aims to induce cross-neutralization against SARS-CoV-2 variants. The phase I and phase II studies were conducted in New Zealand and the Philippines, respectively, for ReCOV primary series. METHODS: Both studies were randomized, double-blind, placebo-controlled designed among COVID-19 vaccine-naïve healthy adults who received two doses of study vaccination with a 21-day interval. In phase I, 100 younger (15-55 years) and older (56-80 years) subjects were 4:1 randomized to receive ReCOV (20 µg or 40 µg) or placebo. In the phase II study, 347 subjects (≥ 18 years) were 2:1 randomized to receive 40 µg ReCOV or placebo. Subjects that received ReCOV were followed up for 6 months after the second dosing. The safety outcomes included solicited and unsolicited AEs, SAEs, and AESIs. The immunogenicity outcomes were live-virus neutralizing antibody (NAb) against prototype, while pseudovirus NAbs against several SARS-CoV-2 variants were included in phase II as well. RESULTS: No related SAE, AESI, or AE leading to early discontinuation were reported. The AE incidences were higher in ReCOV groups than placebo group in phase I while they were similar between study groups in phase II. The majority of solicited AEs were mild or moderate with median duration of 1.0-4.0 days. The common (≥ 10%) solicited AEs in phase I were injection site reactions, headache, pyrexia, fatigue, and myalgia, and common reported (≥ 5%) ones in phase II included injection site pain, headache, and pyrexia. Robust neutralizing activities against the prototype were observed in ReCOV groups, peaking at 14 days post the second dosing: in phase I, the GMTs for 20 µg and 40 µg ReCOV groups were 1643.2 IU/mL (95% CI 1188.5, 2271.9) and 1289.2 IU/mL (95% CI 868.3, 1914.1) in younger adults, and 1122.3 IU/mL (95% CI 722.6, 1743.1) and 680.3 IU/mL (95% CI 440.2, 1051.4) in older adults, respectively, while in the ReCOV group of phase II, the GMTs for subjects with seronegative and seropositive status at baseline were 3741.0 IU/mL (95% CI 3113.4, 4495.0) and 6138.3 IU/mL (95% CI 5255.1, 7169.9), respectively. In phase II, substantial levels of pseudovirus NAbs against SARS-CoV-2 variants were demonstrated; the peak GMTs for prototype, Omicron BA.2, and BA.4/5 were 8857, 4441, and 2644, and 15,667.3, 7334.3, and 4478.8 among seronegative and seropositive subjects, respectively. The neutralization persisted till 6 months post the second dosing, with only 2.5- to 5.2-fold declines for Omicron variants. CONCLUSIONS: Two doses of 20 µg and 40 µg ReCOV are safe and immunogenic against SARS-CoV-2 prototype. The cross-neutralizing activities against Omicron variants support ReCOV advance to late-stage clinical trials. TRIAL REGISTRATION: Phase I study, clinicaltrials.gov NCT04818801; phase II study, clinicaltrials.gov NCT05084989.

13.
Atherosclerosis ; 375: 67-74, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37253281

RESUMO

BACKGROUND AND AIMS: The VOL4002 study assessed the efficacy and safety of volanesorsen in 22 adults with genetically confirmed familial chylomicronaemia syndrome (FCS) treated in the UK Early Access to Medicines Scheme (EAMS), with ("prior exposure") or without ("treatment naive") previous treatment in the APPROACH and/or APPROACH-OLE volanesorsen phase 3 studies. METHODS: Data collection focused on triglyceride (TG) levels, platelet counts and pancreatitis events. Pancreatitis incidence during volanesorsen treatment was compared against the 5-year period preceding volanesorsen exposure. Volanesorsen 285 mg was self-administered subcutaneously once every 2 weeks. RESULTS: Individual patient volanesorsen exposure ranged from 6 to 51 months (total cumulative exposure, 589 months). Among treatment-naive patients (n = 12), volanesorsen treatment resulted in an averaged median 52% reduction (-10.6 mmol/L) from baseline (26.4 mmol/L) in TG levels at 3 months, which were maintained through time points over 15 months of treatment (47%-55% reductions). Similarly, prior-exposure patients (n = 10) experienced a 51% reduction (-17.8 mmol/L) from pre-treatment baseline (28.0 mmol/L), with reductions of 10%-38% over 21 months of treatment. A comparison of pancreatitis event rates found a 74% reduction from the 5-year period before (one event/2.8 years) and during (one event/11.0 years) volanesorsen treatment. Platelet declines were consistent with observations in phase 3 clinical trials. No patient recorded a platelet count <50 × 109/L. CONCLUSIONS: This longitudinal study supports the efficacy of volanesorsen in patients with FCS for lowering TG levels over treatment periods up to 51 months with no apparent safety signals related to increased duration of exposure.


Assuntos
Hiperlipoproteinemia Tipo I , Hipertrigliceridemia , Pancreatite , Adulto , Humanos , Triglicerídeos , Estudos Longitudinais , Hiperlipoproteinemia Tipo I/diagnóstico , Hiperlipoproteinemia Tipo I/tratamento farmacológico , Hiperlipoproteinemia Tipo I/epidemiologia , Pancreatite/tratamento farmacológico , Reino Unido/epidemiologia , Hipertrigliceridemia/tratamento farmacológico
14.
Metabolites ; 13(5)2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37233662

RESUMO

We have reviewed the genetic basis of chylomicronaemia, the difference between monogenic and polygenic hypertriglyceridaemia, its effects on pancreatic, cardiovascular, and microvascular complications, and current and potential future pharmacotherapies. Severe hypertriglyceridaemia (TG > 10 mmol/L or 1000 mg/dL) is rare with a prevalence of <1%. It has a complex genetic basis. In some individuals, the inheritance of a single rare variant with a large effect size leads to severe hypertriglyceridaemia and fasting chylomicronaemia of monogenic origin, termed as familial chylomicronaemia syndrome (FCS). Alternatively, the accumulation of multiple low-effect variants causes polygenic hypertriglyceridaemia, which increases the tendency to develop fasting chylomicronaemia in presence of acquired factors, termed as multifactorial chylomicronaemia syndrome (MCS). FCS is an autosomal recessive disease characterized by a pathogenic variant of the lipoprotein lipase (LPL) gene or one of its regulators. The risk of pancreatic complications and associated morbidity and mortality are higher in FCS than in MCS. FCS has a more favourable cardiometabolic profile and a low prevalence of atherosclerotic cardiovascular disease (ASCVD) compared to MCS. The cornerstone of the management of severe hypertriglyceridaemia is a very-low-fat diet. FCS does not respond to traditional lipid-lowering therapies. Several novel pharmacotherapeutic agents are in various phases of development. Data on the correlation between genotype and phenotype in FCS are scarce. Further research to investigate the impact of individual gene variants on the natural history of the disease, and its link with ASCVD, microvascular disease, and acute or recurrent pancreatitis, is warranted. Volanesorsen reduces triglyceride concentration and frequency of pancreatitis effectively in patients with FCS and MCS. Several other therapeutic agents are in development. Understanding the natural history of FCS and MCS is necessary to rationalise healthcare resources and decide when to deploy these high-cost low-volume therapeutic agents.

15.
Expert Opin Investig Drugs ; 32(5): 417-427, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37212315

RESUMO

BACKGROUND: This study assessed pharmacokinetic (PK) similarity, safety, and immunogenicity of AVT04, a candidate biosimilar, compared with reference product (RP) ustekinumab (EU-approved and US-licensed Stelara®). METHODS: Healthy subjects (N = 298) were randomized 1:1:1 to receive one 45 mg dose of AVT04, EU-RP, or US-RP. The primary PK parameters were Cmax and AUC0-inf. PK similarity was demonstrated if the 90% confidence intervals (CI) for the ratio of geometric means were all contained within the prespecified margins of 80% and 125%. Additional PK parameters, including AUC0-t, were also assessed. Safety and immunogenicity were also assessed until Day 92. RESULTS: After pre-specified protein content normalization, the 90% CI for the ratio of geometric means for primary PK parameters were all contained within the pre-specified bioequivalence margins of 80% and 125%, supporting demonstration of PK similarity between AVT04 and both EU- and US-RP. Secondary PK parameters supported the analysis. Safety and immunogenicity profiles were comparable across all three treatment arms, although the study was not powered to detect small differences in these parameters. CONCLUSION: Results supported a demonstration of PK similarity between candidate biosimilar AVT04, US-RP and EU-RP. Similar safety and immunogenicity were also shown.Clinical trial registration: www.clinicaltrials.gov identifier is NCT04744363.


Assuntos
Medicamentos Biossimilares , Ustekinumab , Adulto , Humanos , Medicamentos Biossimilares/farmacocinética , Equivalência Terapêutica , Adalimumab/farmacocinética , Área Sob a Curva , Método Duplo-Cego
16.
Anthropocene Rev ; 10(1): 146-176, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37255737

RESUMO

An annually laminated succession in Crawford Lake, Ontario, Canada is proposed for the Global boundary Stratotype Section and Point (GSSP) to define the Anthropocene as a series/epoch with a base dated at 1950 CE. Varve couplets of organic matter capped by calcite precipitated each summer in alkaline surface waters reflect environmental change at global to local scales. Spheroidal carbonaceous particles and nitrogen isotopes record an increase in fossil fuel combustion in the early 1950s, coinciding with early fallout from nuclear and thermonuclear testing - 239+240Pu and 14C:12C, the latter more than compensating for the effects of old carbon in this dolomitic basin. Rapid industrial expansion in the North American Great Lakes region led to enhanced leaching of terrigenous elements by acid precipitation during the Great Acceleration, and calcite precipitation was reduced, producing thin calcite laminae around the GSSP that is marked by a sharp decline in elm pollen (Dutch Elm disease). The lack of bioturbation in well-oxygenated bottom waters, supported by the absence of fossil pigments from obligately anaerobic purple sulfur bacteria, is attributed to elevated salinities and high alkalinity below the chemocline. This aerobic depositional environment, highly unusual in a meromictic lake, inhibits the mobilization of Pu, the proposed primary stratigraphic guide for the Anthropocene.

17.
Foot (Edinb) ; 56: 102001, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37027900

RESUMO

BACKGROUND: Intra-articular corticosteroid injections (ICSI) are commonly used in orthopedic practice. Due to concerns about their immunosuppressive effects, we conducted a prospective observational audit, to monitor for COVID-19 infection amongst a group of foot and ankle patients who received an ICSI during the pandemic. PATIENTS AND METHODS: Included were 68 patients (25 males - 43 females, mean age 59.1 years, SD 15.0, range 19 - 90 years) who received a fluoroscopy-guided ICSI within a two-month period during the pandemic. The American Society of Anaesthesiologists (ASA) grade was I in 35 % of patients, II in 58 % and III in 7 %. 16 % of patients had black, Asian or minority ethnic (BAME) background. The dose of methylprednisolone injected was 20 mg for 28 % of the patients, 40 mg for 29 % and 80 mg for 43 %. RESULTS: All patients were available for follow up at one and four weeks post-injection. None reported COVID-19 infection symptoms within this period. The only complication was a flare-up of joint pain. CONCLUSION: Our study showed that the risk of COVID-19 infection to patients receiving foot or ankle ICSI is low. The limitations of this work must be considered, but our findings support the judicious use of corticosteroid injections during the current crisis.


Assuntos
Tornozelo , COVID-19 , Masculino , Feminino , Humanos , Lactente , Pré-Escolar , Criança , Pandemias , COVID-19/epidemiologia , Articulação do Tornozelo , Corticosteroides/efeitos adversos , Injeções Intra-Articulares
18.
PeerJ ; 11: e14847, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36915660

RESUMO

Meromictic Crawford Lake, located in SW Ontario, Canada is characterized by varved sediments, making it suitable for high-resolution paleoecological studies. Freeze cores, the only coring method available that reliably preserves the fragile laminations representative of seasonal deposition in the lake, were used to document siliceous diatom and chrysophyte community structure at an annual resolution from 1930-1990CE. Stratigraphically constrained cluster analysis identified major assemblage changes that are believed to have been caused by local, regional and possibly global anthropogenic impacts. The assemblage changes within the siliceous algae are attributed to regional weather and increased industrial emissions and related effects of acid deposition on the lake's catchment associated with the Great Acceleration -the massive economic, industrial, and demographic expansion beginning in the mid-20th century. Observed increases in spheroidal carbonaceous particles (SCPs) in varved lake sediment dating to the early 1950s record rapidly expanding steel production without emission controls around 30 km upwind of the lake. The findings reported here reflect major changes in earth systems that the Anthropocene Working Group recommends for a proposed epoch to be termed the Anthropocene, providing support for the laminated sediments from Crawford Lake as a potential Global boundary Stratotype Section and Point (GSSP).


Assuntos
Efeitos Antropogênicos , Lagos , Ontário , Sedimentos Geológicos , Ecologia
19.
Mol Psychiatry ; 28(7): 3013-3022, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36792654

RESUMO

The promise of machine learning has fueled the hope for developing diagnostic tools for psychiatry. Initial studies showed high accuracy for the identification of major depressive disorder (MDD) with resting-state connectivity, but progress has been hampered by the absence of large datasets. Here we used regular machine learning and advanced deep learning algorithms to differentiate patients with MDD from healthy controls and identify neurophysiological signatures of depression in two of the largest resting-state datasets for MDD. We obtained resting-state functional magnetic resonance imaging data from the REST-meta-MDD (N = 2338) and PsyMRI (N = 1039) consortia. Classification of functional connectivity matrices was done using support vector machines (SVM) and graph convolutional neural networks (GCN), and performance was evaluated using 5-fold cross-validation. Features were visualized using GCN-Explainer, an ablation study and univariate t-testing. The results showed a mean classification accuracy of 61% for MDD versus controls. Mean accuracy for classifying (non-)medicated subgroups was 62%. Sex classification accuracy was substantially better across datasets (73-81%). Visualization of the results showed that classifications were driven by stronger thalamic connections in both datasets, while nearly all other connections were weaker with small univariate effect sizes. These results suggest that whole brain resting-state connectivity is a reliable though poor biomarker for MDD, presumably due to disease heterogeneity as further supported by the higher accuracy for sex classification using the same methods. Deep learning revealed thalamic hyperconnectivity as a prominent neurophysiological signature of depression in both multicenter studies, which may guide the development of biomarkers in future studies.


Assuntos
Transtorno Depressivo Maior , Humanos , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética , Vias Neurais , Encéfalo/patologia , Neuroimagem
20.
Clin Biochem ; 114: 11-17, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36642392

RESUMO

All humans deal with acute psychological stress periodically. Some individuals are affected by needle phobia in which a heightened sense of arousal is precipitated by venepuncture. Acute psychological stress invokes a range of physiological changes including activation of the sympathetic-adrenal-medullary and hypothalamic-pituitary-adrenal axes. In this review article, we first examine the human response to acute stress. We then provide an overview of how psychological stress in a subject is likely to be a source of pre-analytical variability for certain measurands, and the major biochemical markers that have been studied in research aiming to quantify stress. As such, we highlight how stress can be a hindrance to the accurate interpretation of certain laboratory results (particularly cortisol, prolactin, metanephrines and growth hormone), and point out the role that biochemical analysis might play in future studies looking at the effects of stress on human behaviour.


Assuntos
Sistema Hipotálamo-Hipofisário , Estresse Psicológico , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Sistema Hipófise-Suprarrenal/fisiologia , Hidrocortisona
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