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1.
bioRxiv ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38529507

RESUMO

Fibrous dysplasia (FD) is a mosaic skeletal disorder caused by somatic activating variants in GNAS, encoding for Gαs, which leads to excessive cAMP signaling in bone marrow stromal cells (BMSCs). Despite advancements in our understanding of FD pathophysiology, the effect of Gαs activation in the BMSC transcriptome remains unclear, as well as how this translates into their local influence in the lesional microenvironment. In this study, we analyzed changes induced by Gαs activation in BMSC transcriptome and performed a comprehensive analysis of their production of cytokines and other secreted factors. We performed RNAseq of cultured BMSCs from patients with FD and healthy volunteers, and from an inducible mouse model of FD, and combined their transcriptomic profiles to build a robust FD BMSC genetic signature. Pathways related to Gαs activation, cytokine signaling, and extracellular matrix deposition were identified. In addition, a comprehensive profile of their secreted cytokines and other factors was performed to identify modulation of several key factors we hypothesized to be involved in FD pathogenesis. We also screened circulating cytokines in a collection of plasma samples from patients with FD, finding positive correlations of several cytokines to their disease burden score, as well as to one another and bone turnover markers. Overall, these data support a pro-inflammatory, pro-osteoclastic behavior of BMSCs bearing hyperactive Gαs variants, and point to several cytokines and other secreted factors as possible therapeutic targets and/or circulating biomarkers for FD.

2.
Ann Rheum Dis ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38527764

RESUMO

OBJECTIVES: Inflammatory cytokines that signal through the Janus kinases-signal transducer and activator of transcription (JAK-STAT) pathway, especially interferons (IFNs), are implicated in Sjögren's disease (SjD). Although inhibition of JAKs is effective in other autoimmune diseases, a systematic investigation of IFN-JAK-STAT signalling and the effect of JAK inhibitor (JAKi) therapy in SjD-affected human tissues has not been fully investigated. METHODS: Human minor salivary glands (MSGs) and peripheral blood mononuclear cells (PBMCs) were investigated using bulk or single-cell (sc) RNA sequencing (RNAseq), immunofluorescence (IF) microscopy and flow cytometry. Ex vivo culture assays on PBMCs and primary salivary gland epithelial cell (pSGEC) lines were performed to model changes in target tissues before and after JAKi. RESULTS: RNAseq and IF showed activated JAK-STAT pathway in SjD MSGs. Elevated IFN-stimulated gene (ISGs) expression associated with clinical variables (eg, focus scores, anti-SSA positivity). scRNAseq of MSGs exhibited cell type-specific upregulation of JAK-STAT and ISGs; PBMCs showed similar trends, including markedly upregulated ISGs in monocytes. Ex vivo studies showed elevated basal pSTAT levels in SjD MSGs and PBMCs that were corrected with JAKi. SjD-derived pSGECs exhibited higher basal ISG expressions and exaggerated responses to IFN-ß, which were normalised by JAKi without cytotoxicity. CONCLUSIONS: SjD patients' tissues exhibit increased expression of ISGs and activation of the JAK-STAT pathway in a cell type-dependent manner. JAKi normalises this aberrant signalling at the tissue level and in PBMCs, suggesting a putative viable therapy for SjD, targeting both glandular and extraglandular symptoms. Predicated on these data, a phase Ib/IIa randomised controlled trial to treat SjD with tofacitinib was initiated.

3.
BJA Open ; 10: 100277, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38545565

RESUMO

Oxygen is the most used drug in anaesthesia. Despite such widespread use, optimal perioperative oxygen administration remains highly controversial because of concerns about the competing harms of both hyperoxia and hypoxia. Notwithstanding a Cochrane review concluding that routinely administering a fractional inspired oxygen concentration (FiO2) >0.6 intraoperatively might increase postoperative morbidity and mortality, the World Health Organization (WHO) currently recommends all anaesthetised patients receive 0.8 FiO2 during and immediately after surgery to reduce surgical site infections. Results from the largest trial available at the time of these two reviews (suggesting long-term survival may be worse with high FiO2, particularly in patients with malignant disease) were considered 'biologically implausible' by the WHO's Guideline Development Group. In addition, the integrity of some perioperative oxygen studies has been challenged. Resolving these controversies is of fundamental importance to all perioperative clinicians. This narrative review is based on the inaugural BJA William Mapleson lecture delivered by the senior author (AC) at the 2023 annual meeting of the Royal College of Anaesthetists in Birmingham. We present the current evidence for perioperative oxygen administration and contrast this with how oxygen therapy is targeted in other specialties (e.g. intensive care medicine). We will explore whether anaesthetists follow the WHO recommendations and consider how oxygen administration affects the stress response to surgery. We reason that novel clinical trial designs in combination with targeted experimental medicine studies will be required to improve our understanding of how best to optimise individualised perioperative oxygenation-a cornerstone of anaesthesia.

4.
Cureus ; 16(2): e53469, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38435179

RESUMO

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an autosomal dominant genetic disorder of the small arteries that causes ischemic vascular events, subcortical dementia, behavioral changes, and migraine-like headaches. It is caused by a mutation in the NOTCH3 gene; this disease was first described in 1955 by van Bogaert. We present a 29-year-old woman who presented to the neurology department. She has no history of chronic degenerative diseases. She has been complaining of migraine-like headaches for the past six months. She has cognitive impairment with arithmetic and executive function deficits on neurological examination. Blood biometry and blood chemistry are within normal parameters in her laboratory studies. A viral panel and immunological profile were also performed and were not reactive. A lumbar puncture was performed, and the composition of the cerebrospinal fluid was within normal limits. An MRI was performed, which showed bilateral and symmetric white matter hyperintensities consistent with CADASIL syndrome. There is no specific treatment. Management of these patients is based on symptom control. Neurological sequelae have an important impact on the quality of life and mortality of these patients. For this reason, pharmacological preventive therapies have been sought with controversial evidence.

5.
Br J Anaesth ; 132(5): 945-956, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38368234

RESUMO

BACKGROUND: Pulse oximetry-derived oxygen saturation (SpO2) is an estimate of true arterial oxygen saturation (SaO2). The aim of this review was to evaluate available evidence determining the effect of skin tone on the ability of pulse oximeters to accurately estimate SaO2. METHODS: Published literature was screened to identify clinical and non-clinical studies enrolling adults and children when SpO2 was compared with a paired co-oximetry SaO2 value. We searched literature databases from their inception to March 20, 2023. Risk of bias (RoB) was assessed using the QUADAS-2 tool. Certainty of assessment was evaluated using the GRADE tool. RESULTS: Forty-four studies were selected reporting on at least 222 644 participants (6121 of whom were children) and 733 722 paired SpO2-SaO2 measurements. Methodologies included laboratory studies, prospective clinical, and retrospective clinical studies. A high RoB was detected in 64% of studies and there was considerable heterogeneity in study design, data analysis, and reporting metrics. Only 11 (25%) studies measured skin tone in 2353 (1.1%) participants; the remainder reported participant ethnicity: 68 930 (31.0%) participants were of non-White ethnicity or had non-light skin tones. The majority of studies reported overestimation of SaO2 by pulse oximetry in participants with darker skin tones or from ethnicities assumed to have darker skin tones. Several studies reported no inaccuracy related to skin tone. Meta-analysis of the data was not possible. CONCLUSIONS: Pulse oximetry can overestimate true SaO2 in people with darker skin tones. The clinical relevance of this bias remains unclear, but its magnitude is likely to be greater when SaO2 is lower. SYSTEMATIC REVIEW PROTOCOL: International Prospective Register of Systematic Reviews (PROSPERO): CRD42023390723.


Assuntos
Saturação de Oxigênio , Pigmentação da Pele , Adulto , Criança , Humanos , Estudos Retrospectivos , Revisões Sistemáticas como Assunto , Oximetria/métodos , Oxigênio , Hipóxia
6.
Cell Rep ; 43(2): 113762, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38341856

RESUMO

In the mammalian cortex, even simple sensory inputs or movements activate many neurons, with each neuron responding variably to repeated stimuli-a phenomenon known as trial-by-trial variability. Understanding the spatial patterns and dynamics of this variability is challenging. Using cellular 2-photon imaging, we study visual and auditory responses in the primary cortices of awake mice. We focus on how individual neurons' responses differed from the overall population. We find consistent spatial correlations in these differences that are unique to each trial and linearly scale with the cortical area observed, a characteristic of critical dynamics as confirmed in our neuronal simulations. Using chronic multi-electrode recordings, we observe similar scaling in the prefrontal and premotor cortex of non-human primates during self-initiated and visually cued motor tasks. These results suggest that trial-by-trial variability, rather than being random noise, reflects a critical, fluctuation-dominated state in the cortex, supporting the brain's efficiency in processing information.


Assuntos
Movimento , Neurônios , Camundongos , Animais , Neurônios/fisiologia , Vigília , Mamíferos
7.
Birth Defects Res ; 116(2): e2317, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38362599

RESUMO

BACKGROUND: The condition of monozygotic, monochorionic triplet fetuses with a pair of conjoined twins is extremely rare (close to one in a million births), presents challenges in its management, and with poor prognosis. CASE REPORT: We report a case of monochorionic diamniotic triplet pregnancy, ultrasound at 14 weeks shows a pair of conjoined thoracopagus fetuses, sharing heart, liver, and umbilical cord, in addition to omphalocele. The third fetus, without malformations, presents signs of early heart failure compatible with twin-to-twin transfusion syndrome. It was decided to carry out expectant management where at 18 weeks, intrauterine death of the three fetuses occurs. An abortion is performed by hysterotomy. CONCLUSIONS: The treatment in these cases is discussed, three management options have been proposed: expectant management, selective reduction of the conjoined fetuses, or termination of the pregnancy. A review of the literature found only 12 cases with this combination of pathologies, in which only 3 normal fetuses (25%) survived and none of the conjoined twins survived. To our knowledge, this case is the first of a monochorionic triplet pregnancy with conjoined fetuses complicated with early twin-to-twin transfusion.


Assuntos
Transfusão Feto-Fetal , Gravidez de Trigêmeos , Gêmeos Unidos , Feminino , Gravidez , Humanos , Transfusão Feto-Fetal/complicações , Morte Fetal/etiologia , Feto/anormalidades
8.
Behav Sci (Basel) ; 14(2)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38392463

RESUMO

Social network use has increased in recent years. Social networks are fast-changing and may cause negative effects such as dependence and addiction. Hence, it was decided to establish two research aims: (1) to identify the social network used by university students and their use levels according to their sex and (2) to analyse how age, body mass index, physical activity, emotional intelligence and social network type affect addiction to social networks according to young people's sex. A cross-sectional study was designed involving Spanish university students from Education Degrees. The mean age of the participants was 20.84 years (±2.90). Females made up 69.8% of the sample and males 30.2%. An online questionnaire was administered that included sociodemographic questions, IPAQ-SF and TMMS-24. This study found that all students use WhatsApp and more than 97% have YouTube and Instagram accounts. The linear regression model obtained was as follows: social network addiction = 3.355 + 0.336*emotional attention - 0.263*emotional clarity. There is a positive relationship between social network addiction and emotional attention (r = 0.25; p < 0.001) and negative relationships between social network addiction and emotional clarity (r = -0.16; p = 0.002) and between social network addiction and age (r = -0.17; p = 0.001). University students report lower levels of social network addiction and slightly higher levels of social network addiction among females. In addition, there are significant differences between the average social network addiction scores of university students in terms of their use of Telegram, TikTok and Twitch.

9.
Am J Ophthalmol ; 263: 231-239, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38387826

RESUMO

PURPOSE: To discuss the clinical trial results leading to the US Food and Drug Administration (FDA) approval of anti-complement therapies for geographic atrophy (GA), perspectives on functional data from the GA clinical trials, and how lessons from the FDA approval may guide future directions for basic and clinical research in AMD. DESIGN: Selected literature review with analysis and perspective METHODS: We performed a targeted review of publicly available data from the clinical trials of pegcetacoplan and avacincaptad for the treatment of GA, as well as scientific literature on the natural history of GA and the genetics and basic science of complement in AMD. RESULTS: The approval of pegcetacoplan and avacincaptad was based on an anatomic endpoint of a reduction in the rate of GA expansion over time. However, functional data from 2 phase 3 clinical trials for each drug demonstrated no visual benefit to patients in the treatment groups. Review of the genetics of AMD and the basic science of the role for complement in AMD provides only modest support for targeting complement as treatment for GA expansion, and alternative molecular targets for GA treatment are therefore discussed. Reasons for the disconnect between anatomic and functional outcomes in the clinical trials of anti-complement therapies are discussed, providing insight to guide the configuration of future clinical studies for GA. CONCLUSION: Although avacincaptad and pegcetacoplan are our first FDA-approved treatments for GA, results from the clinical trials failed to show any functional improvement after 1 and 2 years, respectively, calling into question whether the drugs represent a "clinically relevant outcome." To improve the chances of more impactful therapies in the future, we provide basic-science rationale for pursuing non-complement targets; emphasize the importance of ongoing clinical research that more closely pins anatomic features of GA to functional outcomes; and provide suggestions for clinical endpoints for future clinical trials on GA.

10.
Clin Nucl Med ; 49(4): 342-343, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38389206

RESUMO

ABSTRACT: A 79-year-old man with a history of metastatic prostate cancer was initially treated with Eligard and switched to relugolix in 2021. The 2022 bone scan presented superscan and extensive osseous metastatic lesions; some had intense PSMA uptake on the initial PSMA PET scan without nodal or visceral metastatic lesions. We treated him with Pluvicto and relugolix. The intermediate PSMA scan demonstrated prominent bone marrow PSMA uptake. However, PSA decreased 58.5%. We hypothesized that the patient might have a bone flare. The final PSMA scan confirmed our hypothesis. Based on our knowledge, this is the first case of Pluvicto-induced bone flare.


Assuntos
Osso e Ossos , Pirimidinonas , Tomografia Computadorizada por Raios X , Masculino , Humanos , Idoso , Osso e Ossos/diagnóstico por imagem , Compostos de Fenilureia , Tomografia por Emissão de Pósitrons
11.
Ophthalmology ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38336282

RESUMO

PURPOSE: To identify factors for meeting prespecified criteria for switching from bevacizumab to aflibercept in eyes with center-involved diabetic macular edema (CI-DME) and moderate vision loss initially treated with bevacizumab in DRCR Retina Network protocol AC. DESIGN: Post hoc analysis of data from a randomized clinical trial. PARTICIPANTS: Two hundred seventy participants with one or both eyes harboring CI-DME with visual acuity (VA) letter score of 69 to 24 (Snellen equivalent, 20/50-20/320). METHODS: Eligible eyes were assigned to receive intravitreal aflibercept monotherapy (n = 158) or bevacizumab followed by aflibercept if prespecified criteria for switching were met between 12 weeks and 2 years (n = 154). MAIN OUTCOME MEASURES: Meeting switching criteria: (1) at any time, (2) at 12 weeks, and (3) after 12 weeks. Associations between meeting the criteria for switching and factors measured at baseline and 12 weeks were evaluated in univariable analyses. Stepwise procedures were used to select variables for multivariable models. RESULTS: In the group receiving bevacizumab first, older participants showed a higher risk of meeting the switching criteria at any time, with a hazard ratio (HR) for a 10-year increase in age of 1.32 (95% confidence interval [CI], 1.11-1.58). Male participants or eyes with worse baseline VA were more likely to switch at 12 weeks (for male vs. female: odds ratio [OR], 4.84 [95% CI, 1.32-17.81]; 5-letter lower baseline VA: OR, 1.30 [95% CI, 1.03-1.63]). Worse 12-week central subfield thickness (CST; 10-µm greater: HR, 1.06 [95% CI, 1.04-1.07]) was associated with increased risk of switching after 12 weeks. The mean ± standard deviation improvement in visual acuity after completing the switch to aflibercept was 3.7 ± 4.9 letters compared with the day of switching. CONCLUSIONS: The identified factors can be used to refine expectations regarding the likelihood that an eye will meet protocol criteria to switch to aflibercept when treatment is initiated with bevacizumab. Older patients are more likely to be switched. At 12 weeks, thicker CST was predictive of eyes most likely to be switched in the future. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

12.
Bone Res ; 12(1): 10, 2024 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378678

RESUMO

Fibrous dysplasia (FD) is a rare, disabling skeletal disease for which there are no established treatments. Growing evidence supports inhibiting the osteoclastogenic factor receptor activator of nuclear kappa-B ligand (RANKL) as a potential treatment strategy. In this study, we investigated the mechanisms underlying RANKL inhibition in FD tissue and its likely indirect effects on osteoprogenitors by evaluating human FD tissue pre- and post-treatment in a phase 2 clinical trial of denosumab (NCT03571191) and in murine in vivo and ex vivo preclinical models. Histological analysis of human and mouse tissue demonstrated increased osteogenic maturation, reduced cellularity, and reduced expression of the pathogenic Gαs variant in FD lesions after RANKL inhibition. RNA sequencing of human and mouse tissue supported these findings. The interaction between osteoclasts and mutant osteoprogenitors was further assessed in an ex vivo lesion model, which indicated that the proliferation of abnormal FD osteoprogenitors was dependent on osteoclasts. The results from this study demonstrated that, in addition to its expected antiosteoclastic effect, denosumab reduces FD lesion activity by decreasing FD cell proliferation and increasing osteogenic maturation, leading to increased bone formation within lesions. These findings highlight the unappreciated role of cellular crosstalk between osteoclasts and preosteoblasts/osteoblasts as a driver of FD pathology and demonstrate a novel mechanism of action of denosumab in the treatment of bone disease.TRIAL REGISTRATION: ClinicalTrials.gov NCT03571191.


Assuntos
Denosumab , Displasia Fibrosa Óssea , Animais , Humanos , Camundongos , Denosumab/farmacologia , Displasia Fibrosa Óssea/tratamento farmacológico , Ligantes , Osteoblastos/metabolismo , Osteogênese/genética
13.
BJA Open ; 9: 100255, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38298206

RESUMO

Background: Lower fitness is a predictor of adverse outcomes after radical cystectomy. Lockdown measures during the COVID-19 pandemic affected daily physical activity. We hypothesised that lockdown during the pandemic was associated with a reduction in preoperative aerobic fitness and an increase in postoperative complications in patients undergoing radical cystectomy. Methods: We reviewed routine preoperative cardiopulmonary exercise testing (CPET) data collected prior to the pandemic (September 2018 to March 2020) and after lockdown (March 2020 to July 2021) in patients undergoing radical cystectomy. Differences in CPET variables, Postoperative Morbidity Survey (POMS) data, and length of hospital stay were compared. Results: We identified 267 patients (85 pre-lockdown and 83 during lockdown) who underwent CPET and radical cystectomy. Patients undergoing radical cystectomy throughout lockdown had lower ventilatory anaerobic threshold (9.0 [7.9-10.9] vs 10.3 [9.1-12.3] ml kg-1 min-1; P=0.0002), peak oxygen uptake (15.5 [12.9-19.1] vs 17.5 [14.4-21.0] ml kg-1 min-1; P=0.015), and higher ventilatory equivalents for carbon dioxide (34.7 [31.4-38.5] vs 33.4 [30.5-36.5]; P=0.030) compared with pre-lockdown. Changes were more pronounced in males and those aged >65 yr. Patients undergoing radical cystectomy throughout lockdown had a higher proportion of day 5 POMS-defined morbidity (89% vs 75%, odds ratio [OR] 2.698, 95% confidence interval [CI] 1.143-6.653; P=0.019), specifically related to pulmonary complications (30% vs 13%, OR 2.900, 95% CI 1.368-6.194; P=0.007) and pain (27% vs 9%, OR 3.471, 95% CI 1.427-7.960; P=0.004), compared with pre-lockdown on univariate analysis. Conclusions: Lockdown measures in response to the COVID-19 pandemic were associated with a reduction in fitness and an increase in postoperative morbidity among patients undergoing radical cystectomy.

14.
Eur J Case Rep Intern Med ; 11(1): 004219, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38223286

RESUMO

Introduction: Hereditary haemorrhagic telangiectasia (HHT) is a rare multi-organ vascular disease. It is characterised by mucocutaneous telangiectasia, epistaxis, and arteriovenous malformations. Some 70% of patients with HHT are thought to have issues with gastrointestinal (GI) bleeding. Traditional management of GI bleeding in HHT includes monitoring for iron deficiency anaemia, iron replacement, antifibrinolytic therapy and control of identifiable bleeding sites with argon photocoagulation during gastrointestinal endoscopy. Blood transfusion may also be required. Case description: Our case describes a man in his 40s with confirmed HHT, with transfusion-dependent anaemia secondary to GI bleeding. He was commenced on fortnightly bevacizumab (5 mg/kg) for 12 weeks in an attempt to reduce his blood transfusion requirement and manage his anaemia. In the months prior to starting bevacizumab, our patient's transfusion requirement ranged from 3-5 units of packed red cells per month to maintain an Hb >8 g/dl. He had a marked improvement in his symptoms within the first month of treatment and did not require any further blood transfusion during the three months of treatment. He was given one further IV iron infusion in the final month of his 3-month bevacizumab treatment and did not experience any adverse side effects from bevacizumab. Discussion: HHT results from alterations to genes which encode proteins involved in blood vessel formation. This provides the rationale for using anti VEGF drugs such as bevacizumab. Current evidence for this treatment approach is limited. Conclusion: Bevacizumab can be an effective treatment option in patients with HHT refractory to traditional management. LEARNING POINTS: Gastrointestinal bleeding in hereditary haemorrhagic telangiectasia can be difficult to treat.Bevacizumab, an anti-vascular endothelial growth factor, can be used to treat refractory anaemia secondary to gastrointestinal bleeding in hereditary haemorrhagic telangiectasia.

16.
Cell Death Discov ; 10(1): 49, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38272891

RESUMO

Electrical pulse stimulation has been used to enhance the differentiation or proliferation of neuronal progenitor cells in tissue engineering and cancer treatment. Therefore, a comprehensive investigation of the effects caused by its parameters is crucial for improvements in those fields. We propose a study of pulse parameters, to allow the control of N2a cell line fate and behavior. We have focused on designing an experimental setup that allows for the knowledge and control over the environment and the stimulation signals applied. To map the effects of the stimulation on N2a cells, their morphology and the cellular and molecular reactions induced by the pulse stimulation have been analyzed. Immunofluorescence, rt-PCR and western blot analysis have been carried out for this purpose, as well as cell counting. Our results show that low-amplitude electrical pulse stimulation promotes proliferation of N2a cells, whilst amplitudes in the range 250 mV/mm-500 mV/mm induce differentiation. Amplitudes higher than 750 mV/mm produce cell damage at low frequencies. For high frequencies, large amplitudes are needed to cause cell death. An inverse relation has been found between cell density and pulse-induced neuronal differentiation. The best condition for neuronal differentiation was found to be 500 mV/mm at 100 Hz. These findings have been confirmed by up-regulation of the Neurod1 gene. Our preliminary study of the molecular effects of electrical pulse stimulation on N2a offers premonitory clues of the PI3K/Akt/GSK-3ß pathway implications on the neuronal differentiation process through ES. In general, we have successfully mapped the sensitivity of N2a cells to electrical pulse stimulation parameters.

17.
Sci Rep ; 14(1): 1940, 2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253666

RESUMO

The recently discovered deep-sea Capelinhos hydrothermal edifice, ~ 1.5 km of the main Lucky Strike (LS) vent field (northern Mid-Atlantic Ridge), contrasts with the other LS edifices in having poorly-altered end-member hydrothermal fluids with low pH and chlorine, and high metal concentrations. Capelinhos unique chemistry and location offer the opportunity to test the effects of local abiotic filters on faunal community structure while avoiding the often-correlated influence of dispersal limitation and depth. In this paper, we characterize for the first time the distribution patterns of the Capelinhos faunal communities, and analyze the benthic invertebrates (> 250 µm) inhabiting diffusive-flow areas and their trophic structures (δ13C, δ15N and δ34S). We hypothesized that faunal communities would differ from those of the nearest LS vent edifices, showing an impoverished species subset due to the potential toxicity of the chemical environment. Conversely, our results show that: (1) community distribution resembles that of other LS edifices, with assemblages visually dominated by shrimps (close to high-temperature focused-fluid areas) and mussels (at low-temperature diffuse flow areas); (2) most species from diffuse flow areas are well-known LS inhabitants, including the bed-forming and chemosymbiotic mussel Bathymodiolus azoricus and (3) communities are as diverse as those of the most diverse LS edifices. On the contrary, stable isotopes suggest different trophodynamics at Capelinhos. The high δ15N and, especially, δ13C and δ34S values suggest an important role of methane oxidation (i.e., methanotrophy), rather than the sulfide oxidation (i.e., thiotrophy) that predominates at most LS edifices. Our results indicate that Capelinhos shows unique environmental conditions, trophic structure and trophodynamics, yet similar fauna, compared to other LS edifices, which suggest a great environmental and trophic plasticity of the vent faunal communities at the LS.


Assuntos
Cloretos , Decápodes , Animais , Cloro , Temperatura Baixa , Meios de Contraste
18.
Mult Scler Relat Disord ; 83: 105452, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38277981

RESUMO

BACKGROUND: Relapse rates of 47 % have been reported in patients with neuromyelitis optica (NMOSD) using Azathioprine (AZA) and mycophenolate mofetil (MMF). Prediction of non-responders could help determine which patients are most likely to benefit from newer monoclonal antibody treatments from the outset. OBJECTIVES: To identify predictors of AZA and MMF treatment response in NMOSD. METHODS: Multicenter cohort study of NMOSD patients from Brazil and the United Kingdom, treated with AZA and MMF. An unsatisfactory response was defined as one severe or two non-severe attacks in a year. Cox regression was used to identify predictive factors of unsatisfactory response to AZA and MMF. RESULTS: 103 NMOSD patients, mean age 38 years, 83% female, and 65% of Black ethnic group were included. An unsatisfactory IS response was observed in 42% of patients over 2.5 years (IQR 1.0-8.8) years. A severe preceding attack was more common in non-responders (31.1% x 76.7%, p = <0.001). In multivariable analysis, severe attack (RR 3.13; 95 % CI 1.37-7.18, p = 0.007) or higher annualized relapse rate (RR 4.84; 95 % CI 2.01-11.65, p = < 0.001) predicted an unsatisfactory response. Interestingly, Black NMOSD patients had a lower risk of poor response (RR 0.39, 95 % CI 0.17-0.85, p = 0.019). CONCLUSION: Severe attack and a higher annualized relapse rate before AZA or MMF initiation were associated with an unsatisfactory IS response. In patients with these characteristics, treatment with higher-efficacy drugs should be considered from the outset.


Assuntos
Azatioprina , Neuromielite Óptica , Humanos , Feminino , Adulto , Masculino , Azatioprina/uso terapêutico , Ácido Micofenólico/uso terapêutico , Imunossupressores/uso terapêutico , Estudos de Coortes , Resultado do Tratamento , Recidiva
19.
Materials (Basel) ; 17(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38276472

RESUMO

The aim of this study was to investigate the load deflection characteristics of Gummetal® wires in comparison to nickel-titanium (NiTi) wires. Four different NiTi wires and one Gummetal® archwire were analyzed in two dimensions (0.014″ (0.36 mm) and 0.016″ × 0.022″ (0.41 mm × 0.56 mm)) and in two different orientations (edgewise and ribbonwise) using three-point bending tests at T = 37 °C. Force-displacement curves were recorded and analyzed. The Gummetal® 0.014″ wires exhibited higher forces compared to the NiTi wires at 2.0 mm deflection. At 1.0 mm deflection, the opposite pattern was observed. For the 0.016″ × 0.022″ Gummetal® wires, the forces were within the force interval of the NiTi wires at 2.0 mm deflection. At a deflection of 1.0 mm, no residual force was measurable for the Gummetal® wires. All the NiTi wires investigated showed hysteresis and a superelastic plateau. However, the Gummetal® did not form a plateau, but hysteresis was present. An easier plastic deformability compared to the NiTi wires was observed for all the tested geometries.

20.
Women Health ; 64(1): 23-31, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37996389

RESUMO

The study aimed to identify the prevalence of symptoms, changes in exercise levels, and exercise advice received during the menopausal transition in a large multi-country sample. Using total population sampling, 2.5 percent of female Strava app users (n = 970) from 7 countries completed an online survey between 14 February 2019 and 11 March 2019. The survey discussed menopause status (perimenopausal or postmenopausal), menopausal symptoms, changes to exercise behaviors, and advice received concerning exercise during menopause. Frequencies, chi-square statistics, and linear regressions were used to analyze data. The most commonly reported menopausal symptoms were sexual (18-83 percent) and cognitive/psychological (77-78 percent). 41 percent of women reported no change in exercise behavior since menopause began (46 percent increased and 11 percent decreased behaviors). The majority (88 percent) of women did not receive advice regarding exercise during menopause. Women who received advice were more likely to report an increase in their exercise than those not receiving advice (60 percent vs 46 percent; X2 (df 2, n = 927) = 7.1, p = .03). Exercise behaviors increased the longer it had been since the menopausal onset (X2 (df 8, n = 937) = 77.42, p < .001). The results suggested high menopausal symptom prevalence in active women and a general lack of exercise advice. More women reported higher symptom prevalence and an increase in exercise participation, the longer it had been since menopause onset. Future research should determine whether these increased exercise behaviors are being used as a coping mechanism.


Assuntos
Aplicativos Móveis , Feminino , Humanos , Menopausa/psicologia , Inquéritos e Questionários , Fogachos/epidemiologia
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