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1.
J Stroke Cerebrovasc Dis ; 33(6): 107720, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38614162

RESUMO

OBJECTIVES: Prognostication for cerebral venous thrombosis (CVT) remains difficult. We sought to validate the SI2NCAL2C score in an international cohort. MATERIALS AND METHODS: The SI2NCAL2C score was originally developed to predict poor outcome (modified Rankin Scale (mRS) 3-6) at 6 months, and mortality at 30 days and 1 year using data from the International CVT Consortium. The SI2NCAL2C score uses 9 variables: the absence of any female-sex-specific risk factors, intracerebral hemorrhage, central nervous system infection, focal neurological deficits, coma, age, lower level of hemoglobin, higher level of glucose, and cancer. The ACTION-CVT study was an international retrospective study that enrolled consecutive patients across 27 centers. The poor outcome score was validated using 90-day mRS due to lack of follow-up at the 6-month time-point in the ACTION-CVT cohort. Model performance was evaluated using the area under the receiver operating characteristic curve (AUC) and calibration plots. Missing data were imputed using the additive regression and predictive mean matching methods. Bootstrapping was performed with 1000 iterations. RESULTS: Mortality data were available for 950 patients and poor outcome data were available for 587 of 1,025 patients enrolled in ACTION-CVT. Compared to the International CVT Consortium, the ACTION-CVT cohort was older, less often female, and with milder clinical presentation. Mortality was 2.5% by 30 days and 6.0% by one year. At 90-days, 16.7% had a poor outcome. The SI2NCAL2C score had an AUC of 0.74 [95% CI 0.69-0.79] for 90-day poor outcome, 0.72 [0.60-0.82] for mortality by 30 days, and 0.82 [0.76-0.88] for mortality by one year. CONCLUSIONS: The SI2NCAL2C score had acceptable to good performance in an international external validation cohort. The SI2NCAL2C score warrants additional validation studies in diverse populations and clinical implementation studies.

2.
Stroke ; 55(5): 1218-1226, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38572636

RESUMO

BACKGROUND: Decompressive neurosurgery is recommended for patients with cerebral venous thrombosis (CVT) who have large parenchymal lesions and impending brain herniation. This recommendation is based on limited evidence. We report long-term outcomes of patients with CVT treated by decompressive neurosurgery in an international cohort. METHODS: DECOMPRESS2 (Decompressive Surgery for Patients With Cerebral Venous Thrombosis, Part 2) was a prospective, international cohort study. Consecutive patients with CVT treated by decompressive neurosurgery were evaluated at admission, discharge, 6 months, and 12 months. The primary outcome was death or severe disability (modified Rankin Scale scores, 5-6) at 12 months. The secondary outcomes included patient and caregiver opinions on the benefits of surgery. The association between baseline variables before surgery and the primary outcome was assessed by multivariable logistic regression. RESULTS: A total of 118 patients (80 women; median age, 38 years) were included from 15 centers in 10 countries from December 2011 to December 2019. Surgery (115 craniectomies and 37 hematoma evacuations) was performed within a median of 1 day after diagnosis. At last assessment before surgery, 68 (57.6%) patients were comatose, fixed dilated pupils were found unilaterally in 27 (22.9%) and bilaterally in 9 (7.6%). Twelve-month follow-up data were available for 113 (95.8%) patients. Forty-six (39%) patients were dead or severely disabled (modified Rankin Scale scores, 5-6), of whom 40 (33.9%) patients had died. Forty-two (35.6%) patients were independent (modified Rankin Scale scores, 0-2). Coma (odds ratio, 2.39 [95% CI, 1.03-5.56]) and fixed dilated pupil (odds ratio, 2.22 [95% CI, 0.90-4.92]) were predictors of death or severe disability. Of the survivors, 56 (78.9%) patients and 61 (87.1%) caregivers expressed a positive opinion on surgery. CONCLUSIONS: Two-thirds of patients with severe CVT were alive and more than one-third were independent 1 year after decompressive surgery. Among survivors, surgery was judged as worthwhile by 4 out of 5 patients and caregivers. These results support the recommendation to perform decompressive neurosurgery in patients with CVT with impending brain herniation.

3.
Eur Stroke J ; : 23969873241241885, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38572798

RESUMO

INTRODUCTION: Previous reports and meta-analyses derived from small case series reported a mortality rate of up to 40% in patients with coronavirus disease 2019 associated cerebral venous thrombosis (COVID-CVT). We assessed the clinical characteristics and outcomes in an international cohort of patients with COVID-CVT. PATIENTS AND METHODS: This was a registry study of consecutive COVID-CVT patients diagnosed between March 2020 and March 2023. Data collected by the International Cerebral Venous Thrombosis Consortium from patients with CVT diagnosed between 2017 and 2018 served as a comparison. Outcome analyses were adjusted for age and sex. RESULTS: We included 70 patients with COVID-CVT from 23 hospitals in 15 countries and 206 controls from 14 hospitals in 13 countries. The proportion of women was smaller in the COVID-CVT group (50% vs 68%, p < 0.01). A higher proportion of COVID-CVT patients presented with altered mental state (44% vs 25%, p < 0.01), the median thrombus load was higher in COVID-CVT patients (3 [IQR 2-4] vs 2 [1-3], p < 0.01) and the length of hospital stay was longer compared to controls (11 days [IQR 7-20] vs 8 [4-15], p = 0.02). In-hospital mortality did not differ (5/67 [7%, 95% CI 3-16] vs 7/206 [3%, 2-7], aOR 2.6 [95% CI 0.7-9]), nor did the frequency of functional independence after 6 months (modified Rankin Scale 0-2; 45/58 [78%, 95% CI 65-86] vs 161/185 [87%, 81-91], aOR 0.5 [95% CI 0.2-1.02]). CONCLUSION: In contrast to previous studies, the in-hospital mortality rate and functional outcomes during follow-up did not differ between COVID-CVT patients and the pre-COVID-19 controls.

4.
Eur J Neurol ; : e16311, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38646961

RESUMO

BACKGROUND AND PURPOSE: Coma is an independent predictor of poor clinical outcomes in cerebral venous thrombosis (CVT). We aimed to describe the association of age, sex, and radiological characteristics of adult coma patients with CVT. METHODS: We used data from the international, multicentre prospective observational BEAST (Biorepository to Establish the Aetiology of Sinovenous Thrombosis) study. Only positively associated variables with coma with <10% missing data in univariate analysis were considered for the multivariate logistic regression model. RESULTS: Of the 596 adult patients with CVT (75.7% women), 53 (8.9%) patients suffered coma. Despite being a female-predominant disease, the prevalence of coma was higher among men than women (13.1% vs. 7.5%, p = 0.04). Transverse sinus thrombosis was least likely to be associated with coma (23.9% vs. 73.3%, p < 0.001). The prevalence of superior sagittal sinus thrombosis was higher among men than women in the coma sample (73.6% vs. 37.5%, p = 0.01). Men were significantly older than women, with a median (interquartile range) age of 51 (38.5-60) versus 40 (33-47) years in the coma (p = 0.04) and 44.5 (34-58) versus 37 (29-48) years in the non-coma sample (p < 0.001), respectively. Furthermore, an age- and superior sagittal sinus-adjusted multivariate logistic regression model found male sex (odds ratio = 1.8, 95% confidence interval [CI] = 1.0-3.4, p = 0.04) to be an independent predictor of coma in CVT, with an area under the receiver operating characteristic curve of 0.61 (95% CI = 0.52-0.68, p = 0.01). CONCLUSIONS: Although CVT is a female-predominant disease, men were older and nearly twice as likely to suffer from coma than women.

5.
Antonie Van Leeuwenhoek ; 117(1): 47, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427176

RESUMO

Desulfofundulus kuznetsovii is a thermophilic, spore-forming sulphate-reducing bacterium in the family Peptococcaceae. In this study, we describe a newly isolated strain of D. kuznetsovii, strain TPOSR, and compare its metabolism to the type strain D. kuznetsovii 17T. Both strains grow on a large variety of alcohols, such as methanol, ethanol and propane-diols, coupled to the reduction of sulphate. Strain 17T metabolizes methanol via two routes, one involving a cobalt-dependent methyl transferase and the other using a cobalt-independent alcohol dehydrogenase. However, strain TPOSR, which shares 97% average nucleotide identity with D. kuznetsovii strain 17T, lacks several genes from the methyl transferase operon found in strain 17T. The gene encoding the catalytically active methyl transferase subunit B is missing, indicating that strain TPOSR utilizes the alcohol dehydrogenase pathway exclusively. Both strains grew with methanol during cobalt starvation, but growth was impaired. Strain 17T was more sensitive to cobalt deficiency, due to the repression of its methyl transferase system. Our findings shed light on the metabolic diversity of D. kuznetsovii and their metabolic differences of encoding one or two routes for the conversion of methanol.


Assuntos
Álcool Desidrogenase , Metanol , Peptococcaceae , Álcool Desidrogenase/genética , Álcool Desidrogenase/metabolismo , Metanol/metabolismo , Oxirredução , Transferases/metabolismo , Sulfatos/metabolismo , Cobalto , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo
6.
Int J Stroke ; : 17474930241242266, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38494462

RESUMO

BACKGROUND: Due to the rarity of cerebral venous thrombosis (CVT), performing high-quality scientific research in this field is challenging. Providing answers to unresolved research questions will improve prevention, diagnosis, and treatment, and ultimately translate to a better outcome of patients with CVT. We present an international research agenda, in which the most important research questions in the field of CVT are prioritized. AIMS: This research agenda has three distinct goals: (1) to provide inspiration and focus to research on CVT for the coming years, (2) to reinforce international collaboration, and (3) to facilitate the acquisition of research funding. SUMMARY OF REVIEW: This international research agenda is the result of a research summit organized by the International Cerebral Venous Thrombosis Consortium in Amsterdam, the Netherlands, in June 2023. The summit brought together 45 participants from 15 countries including clinical researchers from various disciplines, patients who previously suffered from CVT, and delegates from industry and non-profit funding organizations. The research agenda is categorized into six pre-specified themes: (1) epidemiology and clinical features, (2) life after CVT, (3) neuroimaging and diagnosis, (4) pathophysiology, (5) medical treatment, and (6) endovascular treatment. For each theme, we present two to four research questions, followed by a brief substantiation per question. The research questions were prioritized by the participants of the summit through consensus discussion. CONCLUSIONS: This international research agenda provides an overview of the most burning research questions on CVT. Answering these questions will advance our understanding and management of CVT, which will ultimately lead to improved outcomes for CVT patients worldwide.

7.
Int J Gynecol Cancer ; 34(3): 363-378, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438175

RESUMO

In recent years the role of diagnostic imaging by pelvic ultrasound in the diagnosis and staging of gynecological cancers has been growing exponentially. Evidence from recent prospective multicenter studies has demonstrated high accuracy for pre-operative locoregional ultrasound staging in gynecological cancers. Therefore, in many leading gynecologic oncology units, ultrasound is implemented next to pelvic MRI as the first-line imaging modality for gynecological cancer. The work herein is a consensus statement on the role of pre-operative imaging by ultrasound and other imaging modalities in gynecological cancer, following European Society guidelines.


Assuntos
Neoplasias dos Genitais Femininos , Ginecologia , Feminino , Humanos , Neoplasias dos Genitais Femininos/diagnóstico por imagem , Ultrassonografia , Consenso , Pelve
8.
Stroke ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38511323
9.
Environ Microbiol ; 26(2): e16565, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38356112

RESUMO

Acid mine drainage (AMD) waters are a severe environmental threat, due to their high metal content and low pH (pH <3). Current technologies treating AMD utilize neutrophilic sulfate-reducing microorganisms (SRMs), but acidophilic SRM could offer advantages. As AMDs are low in organics these processes require electron donor addition, which is often incompletely oxidized into organic acids (e.g., acetic acid). At low pH, acetic acid is undissociated and toxic to microorganisms. We investigated the stress response of the acetotrophic Acididesulfobacillus acetoxydans to acetic acid. A. acetoxydans was cultivated in bioreactors at pH 5.0 (optimum). For stress experiments, triplicate reactors were spiked until 7.5 mM of acetic acid and compared with (non-spiked) triplicate reactors for physiological, transcriptomic, and membrane lipid changes. After acetic acid spiking, the optical density initially dropped, followed by an adaptation phase during which growth resumed at a lower growth rate. Transcriptome analysis revealed a downregulation of genes involved in glutamate and aspartate synthesis following spiking. Membrane lipid analysis revealed a decrease in iso and anteiso fatty acid relative abundance; and an increase of acetyl-CoA as a fatty acid precursor. These adaptations allow A. acetoxydans to detoxify acetic acid, creating milder conditions for other microorganisms in AMD environments.


Assuntos
Ácido Acético , Sulfatos , Reatores Biológicos , Ácidos , Ácidos Graxos , Lipídeos de Membrana
10.
mSystems ; 9(3): e0096723, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38323850

RESUMO

The biological route of nitrate reduction has important implications for the bioavailability of nitrogen within ecosystems. Nitrate reduction via nitrite, either to ammonium (ammonification) or to nitrous oxide or dinitrogen (denitrification), determines whether nitrogen is retained within the system or lost as a gas. The acidophilic sulfate-reducing bacterium (aSRB) Acididesulfobacillus acetoxydans can perform dissimilatory nitrate reduction to ammonium (DNRA). While encoding a Nar-type nitrate reductase, A. acetoxydans lacks recognized nitrite reductase genes. In this study, A. acetoxydans was cultivated under conditions conducive to DNRA. During cultivations, we monitored the production of potential nitrogen intermediates (nitrate, nitrite, nitric oxide, hydroxylamine, and ammonium). Resting cell experiments were performed with nitrate, nitrite, and hydroxylamine to confirm their reduction to ammonium, and formed intermediates were tracked. To identify the enzymes involved in DNRA, comparative transcriptomics and proteomics were performed with A. acetoxydans growing under nitrate- and sulfate-reducing conditions. Nitrite is likely reduced to ammonia by the previously undescribed nitrite reductase activity of the NADH-linked sulfite reductase AsrABC, or by a putatively ferredoxin-dependent homolog of the nitrite reductase NirA (DEACI_1836), or both. We identified enzymes and intermediates not previously associated with DNRA and nitrosative stress in aSRB. This increases our knowledge about the metabolism of this type of bacteria and helps the interpretation of (meta)genome data from various ecosystems on their DNRA potential and the nitrogen cycle.IMPORTANCENitrogen is crucial to any ecosystem, and its bioavailability depends on microbial nitrogen-transforming reactions. Over the recent years, various new nitrogen-transforming reactions and pathways have been identified, expanding our view on the nitrogen cycle and metabolic versatility. In this study, we elucidate a novel mechanism employed by Acididesulfobacillus acetoxydans, an acidophilic sulfate-reducing bacterium, to reduce nitrate to ammonium. This finding underscores the diverse physiological nature of dissimilatory reduction to ammonium (DNRA). A. acetoxydans was isolated from acid mine drainage, an extremely acidic environment where nitrogen metabolism is poorly studied. Our findings will contribute to understanding DNRA potential and variations in extremely acidic environments.


Assuntos
Compostos de Amônio , Nitratos , Nitratos/metabolismo , Compostos de Amônio/metabolismo , Nitritos/metabolismo , Ecossistema , Desnitrificação , Bactérias/metabolismo , Hidroxilamina , Nitrito Redutases/metabolismo , Nitrogênio , Hidroxilaminas , Sulfatos
11.
Stroke ; 55(4): 908-918, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38335240

RESUMO

BACKGROUND: Small, randomized trials of patients with cervical artery dissection showed conflicting results regarding optimal stroke prevention strategies. We aimed to compare outcomes in patients with cervical artery dissection treated with antiplatelets versus anticoagulation. METHODS: This is a multicenter observational retrospective international study (16 countries, 63 sites) that included patients with cervical artery dissection without major trauma. The exposure was antithrombotic treatment type (anticoagulation versus antiplatelets), and outcomes were subsequent ischemic stroke and major hemorrhage (intracranial or extracranial hemorrhage). We used adjusted Cox regression with inverse probability of treatment weighting to determine associations between anticoagulation and study outcomes within 30 and 180 days. The main analysis used an as-treated crossover approach and only included outcomes occurring with the above treatments. RESULTS: The study included 3636 patients (402 [11.1%] received exclusively anticoagulation and 2453 [67.5%] received exclusively antiplatelets). By day 180, there were 162 new ischemic strokes (4.4%) and 28 major hemorrhages (0.8%); 87.0% of ischemic strokes occurred by day 30. In adjusted Cox regression with inverse probability of treatment weighting, compared with antiplatelet therapy, anticoagulation was associated with a nonsignificantly lower risk of subsequent ischemic stroke by day 30 (adjusted hazard ratio [HR], 0.71 [95% CI, 0.45-1.12]; P=0.145) and by day 180 (adjusted HR, 0.80 [95% CI, 0.28-2.24]; P=0.670). Anticoagulation therapy was not associated with a higher risk of major hemorrhage by day 30 (adjusted HR, 1.39 [95% CI, 0.35-5.45]; P=0.637) but was by day 180 (adjusted HR, 5.56 [95% CI, 1.53-20.13]; P=0.009). In interaction analyses, patients with occlusive dissection had significantly lower ischemic stroke risk with anticoagulation (adjusted HR, 0.40 [95% CI, 0.18-0.88]; Pinteraction=0.009). CONCLUSIONS: Our study does not rule out the benefit of anticoagulation in reducing ischemic stroke risk, particularly in patients with occlusive dissection. If anticoagulation is chosen, it seems reasonable to switch to antiplatelet therapy before 180 days to lower the risk of major bleeding. Large prospective studies are needed to validate our findings.


Assuntos
Dissecção Aórtica , Fibrilação Atrial , Dissecação da Artéria Carótida Interna , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Inibidores da Agregação Plaquetária/uso terapêutico , Anticoagulantes/uso terapêutico , Fibrinolíticos/uso terapêutico , Estudos Retrospectivos , Dissecação da Artéria Carótida Interna/complicações , Dissecação da Artéria Carótida Interna/tratamento farmacológico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Hemorragia/induzido quimicamente , AVC Isquêmico/tratamento farmacológico , Artérias , Fibrilação Atrial/complicações , Resultado do Tratamento
13.
Antioxidants (Basel) ; 13(2)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38397790

RESUMO

The increasing world population means an increased demand for sustainable processes and products related to foods, particularly those with added health benefits. Plants can be an alternative source of nutritional and biofunctional ingredients. Cytisus plants are an underexploited bioresource, currently prevalent in the Mediterranean Basin and western Asia. This manuscript addresses the processing potential of Cytisus plants for the development of added-value products, including food formulations, food packaging, cosmetics, and therapeutic applications. Most research has reported that Cytisus spp. are a promising source of inexpensive bioactive polyphenol compounds. Cytisus flowers should be considered and exploited as raw materials for the development of new food ingredients (antioxidants, preservatives, additives, etc.), nutraceuticals, or even direct therapeutic agents (anticancer, antibacterial, etc.). In order to evaluate the socioeconomic effect of these underutilized plants, more research is needed to assess their valorization for therapeutic and dietary possibilities, as well as the economic impact.

14.
Water Res ; 252: 121240, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38330717

RESUMO

Glycans are crucial for the structure and function of anaerobic granular sludge in wastewater treatment. Yet, there is limited knowledge regarding the microorganisms and biosynthesis pathways responsible for glycan production. In this study, we analysed samples from anaerobic granular sludges treating papermill and brewery wastewater, examining glycans composition and using metagenome-assembled genomes (MAGs) to explore potential biochemical pathways associated with their production. Uronic acids were the predominant constituents of the glycans in extracellular polymeric substances (EPS) produced by the anaerobic granular sludges, comprising up to 60 % of the total polysaccharide content. MAGs affiliated with Anaerolineacae, Methanobacteriaceae and Methanosaetaceae represented the majority of the microbial community (30-50 % of total reads per MAG). Based on the analysis of MAGs, it appears that Anaerolinea sp. and members of the Methanobacteria class are involved in the production of exopolysaccharides within the analysed granular sludges. These findings shed light on the functional roles of microorganisms in glycan production in industrial anaerobic wastewater treatment systems.


Assuntos
Metagenoma , Esgotos , Esgotos/química , Anaerobiose , Águas Residuárias , Polissacarídeos , Reatores Biológicos/microbiologia , Eliminação de Resíduos Líquidos
15.
Eur Stroke J ; : 23969873241234238, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38400569

RESUMO

INTRODUCTION: Mounting evidence suggests that glucagon-like-peptide-1 receptor-agonists (GLP-1 RAs) attenuate cardiovascular-risk in type-2 diabetes (T2DM). Tirzepatide is the first-in-class, dual glucose-dependent-insulinotropic-polypeptide GIP/GLP-1 RA approved for T2DM. PATIENTS AND METHODS: A systematic review and meta-analysis of randomized-controlled clinical trials (RCTs) was performed to estimate: (i) the incidence of major adverse cardiovascular events (MACE); and (ii) incidence of stroke, fatal, and nonfatal stroke in T2DM-patients treated with GLP-1 or GIP/GLP-1 RAs (vs placebo). RESULTS: Thirteen RCTs (9 and 4 on GLP-1 RAs and tirzepatide, respectively) comprising 65,878 T2DM patients were included. Compared to placebo, GLP-1RAs or GIP/GLP-1 RAs reduced MACE (OR: 0.87; 95% CI: 0.81-0.94; p < 0.01; I2 = 37%), all-cause mortality (OR: 0.88; 95% CI: 0.82-0.96; p < 0.01; I2 = 21%) and cardiovascular-mortality (OR: 0.88; 95% CI: 0.80-0.96; p < 0.01; I2 = 14%), without differences between GLP-1 versus GIP/GLP-1 RAs. Additionally, GLP-1 RAs reduced the odds of stroke (OR: 0.84; 95% CI: 0.76-0.93; p < 0.01; I2 = 0%) and nonfatal stroke (OR: 0.85; 95% CI: 0.76-0.94; p < 0.01; I2 = 0%), whereas no association between fatal stroke and GLP-1RAs was uncovered (OR: 0.80; 95% CI: 0.61-1.05; p = 0.105; I2 = 0%). In secondary analyses, GLP-1 RAs prevented ischemic stroke (OR: 0.74; 95% CI: 0.61-0.91; p < 0.01; I2 = 0%) and MACE-recurrence, but not hemorrhagic stroke (OR: 0.92; 95% CI: 0.51-1.66; p = 0.792; I2 = 0%). There was no association between GLP-1RAs or GIP/GLP-1 RAs and fatal or nonfatal myocardial infarction. DISCUSSION AND CONCLUSION: GLP-1 and GIP/GLP-1 RAs reduce cardiovascular-risk and mortality in T2DM. While there is solid evidence that GLP-1 RAs significantly attenuate the risk of ischemic stroke in T2DM, dedicated RCTs are needed to evaluate the efficacy of novel GIP/GLP-1 RAs for primary and secondary stroke prevention.

16.
Biotechnol Bioeng ; 121(4): 1325-1335, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38265153

RESUMO

Syngas fermentation has gained momentum over the last decades. The cost-efficient design of industrial-scale bioprocesses is highly dependent on quantitative microbial growth data. Kinetic and stoichiometric models for syngas-converting microbes exist, but accurate experimental validation of the derived parameters is lacking. Here, we describe a novel experimental approach for measuring substrate uptake kinetics of gas-fermenting microbes using the model microorganism Clostridium autoethanogenum. One-hour disturbances of a steady-state chemostat bioreactor with increased CO partial pressures (up to 1.2 bar) allowed for measurement of biomass-specific CO uptake- and CO2 production rates ( q CO ${q}_{{CO}}$ , q CO 2 ${q}_{{{CO}}_{2}}$ ) using off-gas analysis. At a pCO of 1.2 bar, a q CO ${q}_{{CO}}$ of -119 ± 1 mmol g-1 X h-1 was measured. This value is 1.8-3.5-fold higher than previously reported experimental and kinetic modeling results for syngas fermenters. Analysis of the catabolic flux distribution reveals a metabolic shift towards ethanol production at the expense of acetate at pCO ≥ $\ge $ 0.6 atm, likely to be mediated by acetate availability and cellular redox state. We characterized this metabolic shift as acetogenic overflow metabolism. These results provide key mechanistic understanding of the factors steering the product spectrum of CO fermentation in C. autoethanogenum and emphasize the importance of dedicated experimental validation of kinetic parameters.


Assuntos
Monóxido de Carbono , Gases , Monóxido de Carbono/metabolismo , Fermentação , Clostridium/metabolismo , Acetatos/metabolismo
17.
Appl Microbiol Biotechnol ; 108(1): 127, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38229305

RESUMO

For several decades, the formation of microbial self-aggregates, known as granules, has been extensively documented in the context of anaerobic digestion. However, current understanding of the underlying microbial-associated mechanisms responsible for this phenomenon remains limited. This study examined morphological and biochemical changes associated with cell aggregation in model co-cultures of the syntrophic propionate oxidizing bacterium Syntrophobacterium fumaroxidans and hydrogenotrophic methanogens, Methanospirillum hungatei or Methanobacterium formicicum. Formerly, we observed that when syntrophs grow for long periods with methanogens, cultures tend to form aggregates visible to the eye. In this study, we maintained syntrophic co-cultures of S. fumaroxidans with either M. hungatei or M. formicicum for a year in a fed-batch growth mode to stimulate aggregation. Millimeter-scale aggregates were observed in both co-cultures within the first 5 months of cultivation. In addition, we detected quorum sensing molecules, specifically N-acyl homoserine lactones, in co-culture supernatants preceding the formation of macro-aggregates (with diameter of more than 20 µm). Comparative transcriptomics revealed higher expression of genes related to signal transduction, polysaccharide secretion and metal transporters in the late-aggregation state co-cultures, compared to the initial ones. This is the first study to report in detail both biochemical and physiological changes associated with the aggregate formation in syntrophic methanogenic co-cultures. KEYPOINTS: • Syntrophic co-cultures formed mm-scale aggregates within 5 months of fed-batch cultivation. • N-acyl homoserine lactones were detected during the formation of aggregates. • Aggregated co-cultures exhibited upregulated expression of adhesins- and polysaccharide-associated genes.


Assuntos
Deltaproteobacteria , Euryarchaeota , Homosserina/metabolismo , Euryarchaeota/metabolismo , Polissacarídeos/metabolismo , Lactonas/metabolismo , Metano/metabolismo
18.
J Am Chem Soc ; 146(2): 1644-1656, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38174960

RESUMO

Photodynamic therapy (PDT), an emergent noninvasive cancer treatment, is largely dependent on the presence of efficient photosensitizers (PSs) and a sufficient oxygen supply. However, the therapeutic efficacy of PSs is greatly compromised by poor solubility, aggregation tendency, and oxygen depletion within solid tumors during PDT in hypoxic microenvironments. Despite the potential of PS-based metal-organic frameworks (MOFs), addressing hypoxia remains challenging. Boron dipyrromethene (BODIPY) chromophores, with excellent photostability, have exhibited great potential in PDT and bioimaging. However, their practical application suffers from limited chemical stability under harsh MOF synthesis conditions. Herein, we report the synthesis of the first example of a Zr-based MOF, namely, 69-L2, exclusively constructed from the BODIPY-derived ligands via a single-crystal to single-crystal post-synthetic exchange, where a direct solvothermal method is not applicable. To increase the PDT performance in hypoxia, we modify 69-L2 with fluorinated phosphate-functionalized methoxy poly(ethylene glycol). The resulting 69-L2@F is an oxygen carrier, enabling tumor oxygenation and simultaneously acting as a PS for reactive oxygen species (ROS) generation under LED irradiation. We demonstrate that 69-L2@F has an enhanced PDT effect in triple-negative breast cancer MDA-MB-231 cells under both normoxia and hypoxia. Following positive results, we evaluated the in vivo activity of 69-L2@F with a hydrogel, enabling local therapy in a triple-negative breast cancer mice model and achieving exceptional antitumor efficacy in only 2 days. We envision BODIPY-based Zr-MOFs to provide a solution for hypoxia relief and maximize efficacy during in vivo PDT, offering new insights into the design of promising MOF-based PSs for hypoxic tumors.


Assuntos
Compostos de Boro , Estruturas Metalorgânicas , Neoplasias , Fotoquimioterapia , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Estruturas Metalorgânicas/química , Fotoquimioterapia/métodos , Zircônio/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Oxigênio , Neoplasias/terapia , Hipóxia , Linhagem Celular Tumoral , Microambiente Tumoral
19.
J Neurointerv Surg ; 16(3): 243-247, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-37185107

RESUMO

BACKGROUND: The periprocedural antithrombotic regimen might affect the risk-benefit profile of emergent carotid artery stenting (eCAS) in patients with acute ischemic stroke (AIS) due to tandem lesions, especially after intravenous thrombolysis. We conducted a systematic review and meta-analysis to evaluate the safety and efficacy of antithrombotics following eCAS. METHODS: We followed PRISMA guidelines and searched MEDLINE, Embase, and Scopus from January 1, 2004 to November 30, 2022 for studies evaluating eCAS in tandem occlusion. The primary endpoint was 90-day good functional outcome. Secondary outcomes were symptomatic intracerebral hemorrhage, in-stent thrombosis, delayed stent thrombosis, and successful recanalization. Meta-analysis of proportions and meta-analysis of odds ratios were implemented. RESULTS: 34 studies with 1658 patients were included. We found that the use of no antiplatelets (noAPT), single antiplatelet (SAPT), dual antiplatelets (DAPT), or glycoprotein IIb/IIIa inhibitors (GPI) yielded similar rates of good functional outcomes, with a marginal benefit of GPI over SAPT (OR 1.88, 95% CI 1.05 to 3.35, Pheterogeneity=0.31). Sensitivity analysis and meta-regression excluded a significant impact of intravenous thrombolysis and Alberta Stroke Program Early CT Score (ASPECTS). We observed no increase in symptomatic intracerebral hemorrhage (sICH) with DAPT or GPI compared with noAPT or SAPT. We also found similar rates of delayed stent thrombosis across groups, with acute in-stent thrombosis showing marginal, non-significant benefits from GPI and DAPT over SAPT and noAPT. CONCLUSIONS: In AIS due to tandem occlusion, the periprocedural antithrombotic regimen of eCAS seems to have a marginal effect on good functional outcome. Overall, high intensity antithrombotic therapy may provide a marginal benefit on good functional outcome and carotid stent patency without a significant increase in risk of sICH.


Assuntos
Doenças das Artérias Carótidas , Estenose das Carótidas , AVC Isquêmico , Acidente Vascular Cerebral , Trombose , Humanos , Fibrinolíticos/efeitos adversos , AVC Isquêmico/etiologia , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/tratamento farmacológico , Stents/efeitos adversos , Inibidores da Agregação Plaquetária , Trombectomia/efeitos adversos , Resultado do Tratamento , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/etiologia , Doenças das Artérias Carótidas/complicações , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/induzido quimicamente , Trombose/etiologia , Estudos Retrospectivos
20.
Int J Stroke ; 19(3): 253-270, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37853529

RESUMO

BACKGROUND: Disparities in the availability of reperfusion services for acute ischemic stroke are considerable globally and require urgent attention. Contemporary data on the availability of reperfusion services in different countries are used to provide the necessary evidence to prioritize where access to acute stroke treatment is needed. AIMS: To provide a snapshot of published literature on the provision of reperfusion services globally, including when facilitated by telemedicine or mobile stroke unit services. METHODS: We searched PubMed to identify original articles, published up to January 2023 for the most recent, representative, and relevant patient-level data for each country. Keywords included thrombolysis, endovascular thrombectomy and telemedicine. We also screened reference lists of review articles, citation history of articles, and the gray literature. The information is provided as a narrative summary. RESULTS: Of 11,222 potentially eligible articles retrieved, 148 were included for review following de-duplications and full-text review. Data were also obtained from national stroke clinical registry reports, Registry of Stroke Care Quality (RES-Q) and PRE-hospital Stroke Treatment Organization (PRESTO) repositories, and other national sources. Overall, we found evidence of the provision of intravenous thrombolysis services in 70 countries (63% high-income countries (HICs)) and endovascular thrombectomy services in 33 countries (68% HICs), corresponding to far less than half of the countries in the world. Recent data (from 2019 or later) were lacking for 35 of 67 countries with known year of data (52%). We found published data on 74 different stroke telemedicine programs (93% in HICs) and 14 active mobile stroke unit pre-hospital ambulance services (80% in HICs) around the world. CONCLUSION: Despite remarkable advancements in reperfusion therapies for stroke, it is evident from available patient-level data that their availability remains unevenly distributed globally. Contemporary published data on availability of reperfusion services remain scarce, even in HICs, thereby making it difficult to reliably ascertain current gaps in the provision of this vital acute stroke treatment around the world.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/terapia , Trombectomia , Ambulâncias , Reperfusão
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