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1.
Biol Rev Camb Philos Soc ; 99(3): 965-978, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38284299

RESUMO

Marine animal forests (MAFs) are benthic ecosystems characterised by biogenic three-dimensional structures formed by suspension feeders such as corals, gorgonians, sponges and bivalves. They comprise highly diversified communities among the most productive in the world's oceans. However, MAFs are in decline due to global and local stressors that threaten the survival and growth of their foundational species and associated biodiversity. Innovative and scalable interventions are needed to address the degradation of MAFs and increase their resilience under global change. Surprisingly, few studies have considered trophic interactions and heterotrophic feeding of MAF suspension feeders as an integral component of MAF conservation. Yet, trophic interactions are important for nutrient cycling, energy flow within the food web, biodiversity, carbon sequestration, and MAF stability. This comprehensive review describes trophic interactions at all levels of ecological organisation in tropical, temperate, and cold-water MAFs. It examines the strengths and weaknesses of available tools for estimating the heterotrophic capacities of the foundational species in MAFs. It then discusses the threats that climate change poses to heterotrophic processes. Finally, it presents strategies for improving trophic interactions and heterotrophy, which can help to maintain the health and resilience of MAFs.


Assuntos
Organismos Aquáticos , Mudança Climática , Animais , Organismos Aquáticos/fisiologia , Processos Heterotróficos , Ecossistema
2.
Biol Rev Camb Philos Soc ; 98(5): 1768-1795, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37236916

RESUMO

The deep sea is amongst the most food-limited habitats on Earth, as only a small fraction (<4%) of the surface primary production is exported below 200 m water depth. Here, cold-water coral (CWC) reefs form oases of life: their biodiversity compares with tropical coral reefs, their biomass and metabolic activity exceed other deep-sea ecosystems by far. We critically assess the paradox of thriving CWC reefs in the food-limited deep sea, by reviewing the literature and open-access data on CWC habitats. This review shows firstly that CWCs typically occur in areas where the food supply is not constantly low, but undergoes pronounced temporal variation. High currents, downwelling and/or vertically migrating zooplankton temporally boost the export of surface organic matter to the seabed, creating 'feast' conditions, interspersed with 'famine' periods during the non-productive season. Secondly, CWCs, particularly the most common reef-builder Desmophyllum pertusum (formerly known as Lophelia pertusa), are well adapted to these fluctuations in food availability. Laboratory and in situ measurements revealed their dietary flexibility, tissue reserves, and temporal variation in growth and energy allocation. Thirdly, the high structural and functional diversity of CWC reefs increases resource retention: acting as giant filters and sustaining complex food webs with diverse recycling pathways, the reefs optimise resource gains over losses. Anthropogenic pressures, including climate change and ocean acidification, threaten this fragile equilibrium through decreased resource supply, increased energy costs, and dissolution of the calcium-carbonate reef framework. Based on this review, we suggest additional criteria to judge the health of CWC reefs and their chance to persist in the future.


Assuntos
Antozoários , Recifes de Corais , Animais , Ecossistema , Concentração de Íons de Hidrogênio , Água do Mar , Água
3.
Sci Rep ; 13(1): 4336, 2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36928759

RESUMO

The aim of the study was to evaluate the impact of the newly developed Similar patient search (SPS) Web Service, which supports reading complex lung diseases in computed tomography (CT), on the diagnostic accuracy of residents. SPS is an image-based search engine for pre-diagnosed cases along with related clinical reference content ( https://eref.thieme.de ). The reference database was constructed using 13,658 annotated regions of interest (ROIs) from 621 patients, comprising 69 lung diseases. For validation, 50 CT scans were evaluated by five radiology residents without SPS, and three months later with SPS. The residents could give a maximum of three diagnoses per case. A maximum of 3 points was achieved if the correct diagnosis without any additional diagnoses was provided. The residents achieved an average score of 17.6 ± 5.0 points without SPS. By using SPS, the residents increased their score by 81.8% to 32.0 ± 9.5 points. The improvement of the score per case was highly significant (p = 0.0001). The residents required an average of 205.9 ± 350.6 s per case (21.9% increase) when SPS was used. However, in the second half of the cases, after the residents became more familiar with SPS, this increase dropped to 7%. Residents' average score in reading complex chest CT scans improved by 81.8% when the AI-driven SPS with integrated clinical reference content was used. The increase in time per case due to the use of the SPS was minimal.


Assuntos
Pneumopatias , Pilotos , Humanos , Doenças Raras , Leitura , Tomografia Computadorizada por Raios X/métodos , Pneumopatias/diagnóstico por imagem , Inteligência Artificial
4.
Clin Infect Dis ; 76(3): e240-e249, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35717657

RESUMO

BACKGROUND: The rapid emergence of the Omicron variant and its large number of mutations led to its classification as a variant of concern (VOC) by the World Health Organization. Subsequently, Omicron evolved into distinct sublineages (eg, BA.1 and BA.2), which currently represent the majority of global infections. Initial studies of the neutralizing response toward BA.1 in convalescent and vaccinated individuals showed a substantial reduction. METHODS: We assessed antibody (immunoglobulin G [IgG]) binding, ACE2 (angiotensin-converting enzyme 2) binding inhibition, and IgG binding dynamics for the Omicron BA.1 and BA.2 variants compared to a panel of VOCs/variants of interest, in a large cohort (N = 352) of convalescent, vaccinated, and infected and subsequently vaccinated individuals. RESULTS: While Omicron was capable of efficiently binding to ACE2, antibodies elicited by infection or immunization showed reduced binding capacities and ACE2 binding inhibition compared to wild type. Whereas BA.1 exhibited less IgG binding compared to BA.2, BA.2 showed reduced inhibition of ACE2 binding. Among vaccinated samples, antibody binding to Omicron only improved after administration of a third dose. CONCLUSIONS: Omicron BA.1 and BA.2 can still efficiently bind to ACE2, while vaccine/infection-derived antibodies can bind to Omicron. The extent of the mutations within both variants prevents a strong inhibitory binding response. As a result, both Omicron variants are able to evade control by preexisting antibodies.


Assuntos
Enzima de Conversão de Angiotensina 2 , Imunoglobulina G , Humanos , Imunização , Mutação , Complicações Pós-Operatórias , Anticorpos Antivirais , Anticorpos Neutralizantes
5.
Front Immunol ; 14: 1264179, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38164132

RESUMO

Signal-regulatory protein α (SIRPα) expressed by myeloid cells is of particular interest for therapeutic strategies targeting the interaction between SIRPα and the "don't eat me" ligand CD47 and as a marker to monitor macrophage infiltration into tumor lesions. To address both approaches, we developed a set of novel human SIRPα (hSIRPα)-specific nanobodies (Nbs). We identified high-affinity Nbs targeting the hSIRPα/hCD47 interface, thereby enhancing antibody-dependent cellular phagocytosis. For non-invasive in vivo imaging, we chose S36 Nb as a non-modulating binder. By quantitative positron emission tomography in novel hSIRPα/hCD47 knock-in mice, we demonstrated the applicability of 64Cu-hSIRPα-S36 Nb to visualize tumor infiltration of myeloid cells. We envision that the hSIRPα-Nbs presented in this study have potential as versatile theranostic probes, including novel myeloid-specific checkpoint inhibitors for combinatorial treatment approaches and for in vivo stratification and monitoring of individual responses during cancer immunotherapies.


Assuntos
Neoplasias , Anticorpos de Domínio Único , Humanos , Camundongos , Animais , Anticorpos de Domínio Único/uso terapêutico , Fagocitose , Células Mieloides/metabolismo , Macrófagos/metabolismo , Neoplasias/terapia , Neoplasias/tratamento farmacológico
6.
Diagnostics (Basel) ; 12(12)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36553055

RESUMO

Superinfections with Aspergillus spp. in patients with Coronavirus disease 2019 (CAPA: COVID-19-associated pulmonary aspergillosis) are increasing. Dexamethasone has shown beneficial effects in critically ill COVID-19 patients. Whether dexamethasone increases the risk of CAPA has not been studied exclusively. Moreover, this retrospective study aimed to identify risk factors for a worse outcome in critically ill COVID-19 patients. Data from 231 critically ill COVID-19 patients with or without dexamethasone treatment from March 2020 and March 2021 were retrospectively analysed. Only 4/169 (6.5%) in the DEXA-group and 13/62 (7.7%) in the Non-DEXA group were diagnosed with probable CAPA (p = 0.749). Accordingly, dexamethasone was not identified as a risk factor for CAPA. Moreover, CAPA was not identified as an independent risk factor for death in multivariable analysis (p = 0.361). In contrast, elevated disease severity (as assessed by Sequential Organ Failure Assessment [SOFA]-score) and the need for organ support (kidney replacement therapy and extracorporeal membrane oxygenation [ECMO]) were significantly associated with a worse outcome. Therefore, COVID-19 treatment with dexamethasone did not increase the risk for CAPA. Moreover, adequately treated CAPA did not represent an independent risk factor for mortality. Accordingly, CAPA might reflect patients' severe disease state instead of directly influencing outcome.

7.
Oncol Res Treat ; 45(10): 598-607, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35764064

RESUMO

AIM: The present exploratory study investigated the diagnostic value of inflammatory markers in patients with breast cancer to predict anti-tumour treatment-related cardiac events. METHODS: Twenty-one patients with breast cancer were enrolled in this prospective observational study and followed over 6 months. Transthoracic echocardiography and measurement of cardiac (N-terminal prohormone of brain natriuretic peptide (NT-proBNP), troponin I (TnI)) and inflammatory biomarkers (vascular adhesion molecule 1 (VCAM-1), soluble suppression of tumorigenesis-2 (sST2), adiponectin) was performed at 3-month intervals (baseline, follow-up, final visit). Cardiac events were defined as decrease in left ventricular ejection fraction (LVEF, decrease by 10% or <50%) or increase in global longitudinal strain (GLS, increase by 15% or > -16%), as a more sensitive marker of LV function. RESULTS: Cardiac deterioration was observed in 9 out of 21 patients (event group). While LVEF did not differ significantly between the two groups (event vs. no event) at any visit, GLS was significantly higher during follow-up (follow-up: event -16 ± 3.3% vs. no event -18 ± 1.6%, p = 0.04; final visit: event -16 ± 2.1% vs. no event -19 ± 1.9%, p = 0.003). NT-proBNP was numerically higher in patients with a cardiac event during all visits, with NT-proBNP negatively correlated with LVEF and MAPSE (both r = -0.33, p = 0.02), whereas GLS (r = 0.40, p = 0.006), TnI (r = 0.44, p = 0.001), and VCAM-1 (r = 0.48, p = 0.003) showed a positive association with NT-proBNP. In comparison, higher VCAM-1 and sST2 concentrations were detected in the event group at both baseline and the final visit, with a significant difference for baseline (VCAM-1: p = 0.02; sST2: p = 0.03). Adiponectin was also lower in patients with a treatment-related event. Thresholds for VCAM-1 >762 ng/mL and sST2 >18.7 ng/mL, as detected by ROC analysis, correlated best with the primary endpoint. CONCLUSION: Cardiac events during anti-tumour treatment in patients with breast cancer are relatively common. Inflammatory markers such as VCAM-1 or sST2 were associated with an increased likelihood for occurrence of a treatment-related event, which may therefore hold the promise to better identify patients at high risk.


Assuntos
Neoplasias da Mama , Peptídeo Natriurético Encefálico , Adiponectina , Biomarcadores , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Proteína 1 Semelhante a Receptor de Interleucina-1 , Fragmentos de Peptídeos , Projetos Piloto , Prognóstico , Volume Sistólico , Troponina I , Molécula 1 de Adesão de Célula Vascular , Função Ventricular Esquerda
8.
Clin Nucl Med ; 47(11): e718-e721, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35714372

RESUMO

ABSTRACT: Ventilation/perfusion SPECT/CT has very high sensitivity with little false-positive findings for diagnosing pulmonary embolism (PE). However, bronchopulmonary tumors or structural changes of the lungs' vasculature infrequently mimic PE. Here, a 59-year-old man presented with acute dyspnea and acute renal failure 5 years after bilateral lung transplant. Pulmonary ventilation/perfusion SPECT/CT was performed demonstrating a lobar mismatch of the left upper lung lobe indicative for PE. Bronchoscopy revealed local hyperemia of this lobe, indicating prolonged venous blood return. Subsequent CT angiography confirmed postsurgical upper pulmonary vein obliteration as final diagnosis. In conclusion, pulmonary vein obliteration might cause false-positive ventilation/perfusion SPECT/CT.


Assuntos
Transplante de Pulmão , Embolia Pulmonar , Humanos , Pulmão/diagnóstico por imagem , Transplante de Pulmão/efeitos adversos , Masculino , Pessoa de Meia-Idade , Perfusão , Embolia Pulmonar/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Relação Ventilação-Perfusão
9.
Anal Chem ; 94(27): 9863-9871, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35749695

RESUMO

N-linked glycosylation is a ubiquitous posttranslational modification of proteins. While it plays an important role in the biological function of proteins, it often poses a major challenge for their analytical characterization. Currently available peptide N-glycanases (PNGases) are often inefficient at deglycosylating proteins due to sterically inaccessible N-glycosylation sites. This usually leads to poor sequence coverage in bottom-up analysis using liquid chromatography with tandem mass spectrometry and makes it impossible to obtain an intact mass signal in top-down MS analysis. In addition, most PNGases operate optimally only in the neutral to slightly acidic pH range and are severely compromised in the presence of reducing and denaturing substances, which limits their use for advanced bioanalysis based on hydrogen-deuterium exchange in combination with mass spectrometry (HDX-MS). Here, we present a novel peptide N-glycanase from Rudaea cellulosilytica (PNGase Rc) for which we demonstrate broad substrate specificity for N-glycan hydrolysis from multiply occupied and natively folded proteins. Our results show that PNGase Rc is functional even under challenging, HDX quenching conditions (pH 2.5, 0 °C) and in the presence of 0.4 M tris(2-carboxyethyl)phosphine, 4 M urea, and 1 M guanidinium chloride. Most importantly, we successfully applied the PNGase Rc in an HDX-MS workflow to determine the epitope of a nanobody targeting the extracellular domain of human signal-regulating protein alpha (SIRPα).


Assuntos
Medição da Troca de Deutério , Hidrogênio , Deutério , Medição da Troca de Deutério/métodos , Mapeamento de Epitopos , Humanos , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase/metabolismo , Espectrometria de Massas em Tandem
10.
Semin Nucl Med ; 52(6): 816-823, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35624033

RESUMO

Malignant pleural mesothelioma is a rare type of cancer, whose incidence, however, is increasing and will presumably continue to rise in the coming years. Key features of this disease comprise its mantle-shaped, pleura-associated, often multifocal growth, which cause diagnostic challenges. A growing number of mesotheliomas are being treated with novel immunotherapies for which no image derived general response criteria have been established. However, recent studies indicate that FDG-PET/CT could be superior for response assessment compared to CT-based criteria. This article aims at providing an overview of response assessment criteria dedicated to malignant pleural mesothelioma, such as mRECIST, iRECIST, and PERCIST. In addition, the potential future role of PET/CT in the management of malignant pleural mesothelioma will also be discussed.


Assuntos
Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurais , Humanos , Mesotelioma Maligno/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias Pleurais/diagnóstico por imagem , Neoplasias Pleurais/terapia , Fluordesoxiglucose F18 , Mesotelioma/diagnóstico por imagem , Mesotelioma/terapia , Tomografia por Emissão de Pósitrons
11.
PeerJ ; 9: e12609, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34966598

RESUMO

In the North Patagonian fjord region, the cold-water coral (CWC) Desmophyllum dianthus occurs in high densities, in spite of low pH and aragonite saturation. If and how these conditions affect the energy demand of the corals is so far unknown. In a laboratory experiment, we investigated the carbon and nitrogen (C, N) budget of D. dianthus from Comau Fjord under three feeding scenarios: (1) live fjord zooplankton (100-2,300 µm), (2) live fjord zooplankton plus krill (>7 mm), and (3) four-day food deprivation. In closed incubations, C and N budgets were derived from the difference between C and N uptake during feeding and subsequent C and N loss through respiration, ammonium excretion, release of particulate organic carbon and nitrogen (POC, PON). Additional feeding with krill significantly increased coral respiration (35%), excretion (131%), and POC release (67%) compared to feeding on zooplankton only. Nevertheless, the higher C and N losses were overcompensated by the threefold higher C and N uptake, indicating a high assimilation and growth efficiency for the krill plus zooplankton diet. In contrast, short food deprivation caused a substantial reduction in respiration (59%), excretion (54%), release of POC (73%) and PON (87%) compared to feeding on zooplankton, suggesting a high potential to acclimatize to food scarcity (e.g., in winter). Notwithstanding, unfed corals 'lost' 2% of their tissue-C and 1.2% of their tissue-N per day in terms of metabolism and released particulate organic matter (likely mucus). To balance the C (N) losses, each D. dianthus polyp has to consume around 700 (400) zooplankters per day. The capture of a single, large krill individual, however, provides enough C and N to compensate daily C and N losses and grow tissue reserves, suggesting that krill plays an important nutritional role for the fjord corals. Efficient krill and zooplankton capture, as well as dietary and metabolic flexibility, may enable D. dianthus to thrive under adverse environmental conditions in its fjord habitat; however, it is not known how combined anthropogenic warming, acidification and eutrophication jeopardize the energy balance of this important habitat-building species.

12.
ACS Appl Mater Interfaces ; 13(46): 55534-55549, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34762399

RESUMO

A full understanding of the relationship between surface properties, protein adsorption, and immune responses is lacking but is of great interest for the design of biomaterials with desired biological profiles. In this study, polyelectrolyte multilayer (PEM) coatings with gradient changes in surface wettability were developed to shed light on how this impacts protein adsorption and immune response in the context of material biocompatibility. The analysis of immune responses by peripheral blood mononuclear cells to PEM coatings revealed an increased expression of proinflammatory cytokines tumor necrosis factor (TNF)-α, macrophage inflammatory protein (MIP)-1ß, monocyte chemoattractant protein (MCP)-1, and interleukin (IL)-6 and the surface marker CD86 in response to the most hydrophobic coating, whereas the most hydrophilic coating resulted in a comparatively mild immune response. These findings were subsequently confirmed in a cohort of 24 donors. Cytokines were produced predominantly by monocytes with a peak after 24 h. Experiments conducted in the absence of serum indicated a contributing role of the adsorbed protein layer in the observed immune response. Mass spectrometry analysis revealed distinct protein adsorption patterns, with more inflammation-related proteins (e.g., apolipoprotein A-II) present on the most hydrophobic PEM surface, while the most abundant protein on the hydrophilic PEM (apolipoprotein A-I) was related to anti-inflammatory roles. The pathway analysis revealed alterations in the mitogen-activated protein kinase (MAPK)-signaling pathway between the most hydrophilic and the most hydrophobic coating. The results show that the acute proinflammatory response to the more hydrophobic PEM surface is associated with the adsorption of inflammation-related proteins. Thus, this study provides insights into the interplay between material wettability, protein adsorption, and inflammatory response and may act as a basis for the rational design of biomaterials.


Assuntos
Anti-Inflamatórios/química , Materiais Revestidos Biocompatíveis/química , Citocinas/imunologia , Inflamação/imunologia , Polieletrólitos/química , Adsorção , Anti-Inflamatórios/farmacologia , Células Cultivadas , Materiais Revestidos Biocompatíveis/farmacologia , Citocinas/análise , Citocinas/biossíntese , Ensaio de Imunoadsorção Enzimática , Humanos , Interações Hidrofóbicas e Hidrofílicas , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Tamanho da Partícula , Polieletrólitos/farmacologia , Propriedades de Superfície , Molhabilidade
13.
Eur J Public Health ; 31(6): 1170-1176, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34516614

RESUMO

BACKGROUND: Cardiooncology is a relatively new subspeciality, investigating the side effects of cytoreductive therapies on the cardiovascular (CV) system. Gender differences are well known in oncological and CV diseases, but are less elucidated in cardiooncological collectives. METHODS: Five hundred and fifty-one patients (278 male, 273 female) with diagnosed cancer who underwent regular cardiological surveillance were enrolled in the 'MAnnheim Registry for CardioOncology' and followed over a median of 41 (95% confidence interval: 40-43) months. RESULTS: Female patients were younger at the time of first cancer diagnosis [median 60 (range 50-70) vs. 66 (55-75), P = 0.0004], while the most common tumour was breast cancer (49.8%). Hyperlipidaemia was more often present in female patients (37% vs. 25%, P = 0.001). Male patients had a higher cancer susceptibility than female patients. They suffered more often from hypertension (51% vs. 67%, P = 0.0002) or diabetes (14% vs. 21%, P = 0.02) and revealed more often vitamin D deficiency [(U/l) median 26.0 (range 17-38) vs. 16 (9-25), P = 0.002] and anaemia [(g/dl) median 11.8 (range 10.4-12.9) vs. 11.7 (9.6-13.6), P = 0.51]. During follow-up, 140 patients died (male 77, female 63; P = 0.21). An increased mortality rate was observed in male patients (11.4% vs. 14%, P = 0.89), with even higher mortality rates of up to 18.9% vs. 7.7% (P = 0.02) considering tumours that can affect both sexes compared. CONCLUSIONS: Although female patients were younger at the time of first cancer diagnosis, male patients had both higher cancer susceptibility and an increased mortality risk. Concomitant CV diseases were more common in male patients.


Assuntos
Anemia , Neoplasias da Mama , Doenças Cardiovasculares , Doenças Cardiovasculares/epidemiologia , Feminino , Humanos , Masculino , Sistema de Registros , Fatores de Risco
14.
J Radiol Prot ; 41(3)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34406127

RESUMO

Cardiac and liver computed tomography (CT) perfusion has not been routinely implemented in the clinic and requires high radiation doses. The purpose of this study is to examine the radiation exposure and technical settings for cardiac and liver CT perfusion scans at different CT scanners. Two cardiac and three liver CT perfusion protocols were examined with the N1 LUNGMAN phantom at three multi-slice CT scanners: a single-source (I) and second- (II) and third-generation (III) dual-source CT scanners. Radiation doses were reported for the CT dose index (CTDIvol) and dose-length product (DLP) and a standardised DLP (DLP10cm) for cardiac and liver perfusion. The effective dose (ED10cm) for a standardised scan length of 10 cm was estimated using conversion factors based on the International Commission on Radiological Protection (ICRP) 110 phantoms and tissue-weighting factors from ICRP 103. The proposed total lifetime attributable risk of developing cancer was determined as a function of organ, age and sex for adults. Radiation exposure for CTDIvol, DLP/DLP10 cmand ED10 cmduring CT perfusion was distributed as follows: for cardiac perfusion (II) 144 mGy, 1036 mGy·cm/1440 mGy·cm and 39 mSv, and (III) 28 mGy, 295 mGy·cm/279 mGy·cm and 8 mSv; for liver perfusion (I) 225 mGy, 3360 mGy·cm/2249 mGy·cm and 54 mSv, (II) 94 mGy, 1451 mGy·cm/937 mGy·cm and 22 mSv, and (III) 74 mGy, 1096 mGy·cm/739 mGy·cm and 18 mSv. The third-generation dual-source CT scanner applied the lowest doses. Proposed total lifetime attributable risk increased with decreasing age. Even though CT perfusion is a high-dose examination, we observed that new-generation CT scanners could achieve lower doses. There is a strong impact of organ, age and sex on lifetime attributable risk. Further investigations of the feasibility of these perfusion scans are required for clinical implementation.


Assuntos
Fígado , Tomografia Computadorizada por Raios X , Fígado/diagnóstico por imagem , Perfusão , Imagens de Fantasmas , Doses de Radiação
15.
Bioconjug Chem ; 32(9): 1960-1965, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34406760

RESUMO

N-Hydroxysuccinimide esters of small molecules are widely used to modify biomolecules such as antibodies or proteins. Primary amine groups preferably react with the ester to form covalent amide bonds. Currently, protocols strongly recommend replacing the buffer reagent tris(hydroxymethyl)aminomethane, and it has even been proposed as a stop reagent. Here, we show that TRIS indeed does not interfere with biotinylation of biomolecules with NHS chemistry.


Assuntos
Succinimidas , Biotinilação , Trometamina
16.
Radiat Prot Dosimetry ; 193(3-4): 237-246, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-33893506

RESUMO

The aim of this phantom study is to examine radiation doses of dual- and single-energy computed tomography (DECT and SECT) in the chest and upper abdomen for three different multi-slice CT scanners. A total of 34 CT protocols were examined with the phantom N1 LUNGMAN. Four different CT examination types of different anatomic regions were performed both in single- and dual-energy technique: chest, aorta, pulmonary arteries for suspected pulmonary embolism and liver. Radiation doses were examined for the CT dose index CTDIvol and dose-length product (DLP). Radiation doses of DECT were significantly higher than doses for SECT. In terms of CTDIvol, radiation doses were 1.1-3.2 times higher, and in terms of DLP, these were 1.1-3.8 times higher for DECT compared with SECT. The third-generation dual-source CT applied the lowest dose in 7 of 15 different examination types of different anatomic regions.


Assuntos
Abdome , Tomografia Computadorizada por Raios X , Imagens de Fantasmas , Doses de Radiação , Tórax
17.
Antibodies (Basel) ; 10(1)2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33808657

RESUMO

Annexin-A1 (ANXA1) belongs to a class of highly homologous Ca2+-dependent phospholipid-binding proteins. Its structure consists of a core region composed of four homologous repeats arranged in a compact, hydrolysis-resistant structure and an N-terminal region with a Ca2+-dependent conformation. ANXA1 is involved in several processes, including cell proliferation, apoptosis, metastasis, and the inflammatory response. Therefore, the development of antibodies blocking selected regions on ANXA1 holds great potential for the development of novel therapeutics treating inflammatory and cancer diseases. Here, we report the interaction site between an ANXA1-specific antibody known to inhibit T cell activation without adverse cytotoxic effects and ANXA1 using amide hydrogen-deuterium exchange mass spectrometry (HDX-MS). For the epitope determination, we applied two bottom-up HDX-MS approaches with pepsin digestion in solution and immobilized on beads. Both strategies revealed the interaction region within domain III of ANXA1 in Ca2+-bound conformation. The antibody-binding region correlates with the hydrophobic binding pocket of the N-terminal domain formed in the absence of calcium. This study demonstrates that even cryptic and flexible binding regions can be studied by HDX-MS, allowing a fast and efficient determination of the binding sites of antibodies which will help to define a mode of action profile for their use in therapy.

18.
Math Med Biol ; 38(1): 1-27, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-32671383

RESUMO

In this paper, we study a single serotype transmission model of dengue to determine the optimal vaccination age for Dengvaxia. The transmission dynamics are modelled with an age-dependent force of infection. The force of infection for each serotype is derived from the serological profile of dengue in Brazil without serotype distinction and from serotype-specific reported cases. The risk due to an infection is measured by the probability of requiring hospitalization based on Brazilian Ministry of Health data. The optimal vaccination age is determined for any number and combination of the four distinct dengue virus serotypes DENv1-4. The lifetime expected risk is adapted to include antibody dependent enhancement (ADE) and permanent cross-immunity after two heterologous infections. The risk is assumed to be serostatus-dependent. The optimal vaccination age is computed for constant, serostatus-specific vaccine efficacies. Additionally, the vaccination age is restricted to conform to the licence of Dengvaxia in Brazil and the achievable and minimal lifetime expected risks are compared. The optimal vaccination age obtained for the risk of hospitalization varies significantly with the assumptions relating to ADE and cross-immunity. Risk-free primary infections lead to higher optimal vaccination ages, as do asymptomatic third and fourth infections. Sometimes vaccination is not recommended at all, e.g. for any endemic area with a single serotype if primary infections are risk-free. Restricting the vaccination age to Dengvaxia licensed ages mostly leads to only a slightly higher lifetime expected risk and the vaccine should be administered as close as possible to the optimal vaccination age.


Assuntos
Vacinas contra Dengue/administração & dosagem , Vírus da Dengue/classificação , Vírus da Dengue/imunologia , Dengue/prevenção & controle , Aedes/virologia , Fatores Etários , Animais , Anticorpos Antivirais/sangue , Brasil/epidemiologia , Dengue/epidemiologia , Dengue/transmissão , Doenças Endêmicas/prevenção & controle , Doenças Endêmicas/estatística & dados numéricos , Feminino , Humanos , Imunidade Materno-Adquirida , Masculino , Conceitos Matemáticos , Modelos Biológicos , Mosquitos Vetores/virologia , Fatores de Risco , Sorogrupo , Vacinação/estatística & dados numéricos
19.
Ther Adv Respir Dis ; 14: 1753466620932507, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32615853

RESUMO

BACKGROUND: Bronchoscopic lung volume reduction (BLVR) via valve implantation can be achieved by targeting severely hyperinflated and emphysematously destructed lung areas in patients with chronic obstructive lung disease. Lack of collateral ventilation (CV) is important for good outcomes with BLVR. CV can be measured using the catheter-based Chartis system. The aim of this study was to evaluate the correlation between total exhaled volume drained from the target lobe measured by Chartis and clinical outcomes after BLVR in CV-negative patients. METHODS: From January 2016 to March 2019, 60 patients were included in this retrospective single-center analysis. Drained volume (TVol) measured by Chartis was recorded and compared with lung function and physical performance parameters. Outcome variables included the percentage change in lung function [forced expiratory volume in 1 s (FEV1), residual volume (RV), and inspiratory vital capacity (IVC)]. Secondary outcomes were the degree of target lobe volume reduction (TLVR), change in 6-min walk distance (6MWD), and change in chronic obstructive pulmonary disease (COPD) assessment test (CAT) score. RESULTS: Drained volume correlated significantly with post-BLVR change in FEV1 (r = 0.663), IVC (r = 0.611), RV (r = -0.368), and TLVR (r = 0.635) (all p < 0.05). In a priori-defined patient subgroups based on drained volume [<100 ml (n = 19), 100-400 ml (n = 33), and >400 ml (n = 8)]; mean changes in FEV1 were 2.6%, 17.4%, and 51.3%; in RV were -3.9%, -10.6%, and -23.8%; in IVC were -4.0%, 10.6%, and 62.4%; and in TLVR were 525 ml (39%), 1375 ml (73%) and 1760 ml (100%), respectively. There were no significant correlations between absolute and percentage changes in 6MWD and the CAT score. Lung volume reduction was diagnosed in 32 (53%) cases. CONCLUSION: Drained volume measured by the Chartis system correlated with functional improvement in CV-negative patients undergoing BLVR. The reviews of this paper are available via the supplemental material section.


Assuntos
Broncoscopia , Pulmão/cirurgia , Doença Pulmonar Obstrutiva Crônica/cirurgia , Enfisema Pulmonar/cirurgia , Idoso , Broncoscopia/efeitos adversos , Broncoscopia/instrumentação , Feminino , Volume Expiratório Forçado , Humanos , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Medidas de Volume Pulmonar , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Enfisema Pulmonar/diagnóstico , Enfisema Pulmonar/fisiopatologia , Recuperação de Função Fisiológica , Estudos Retrospectivos , Resultado do Tratamento , Capacidade Vital
20.
Sci Rep ; 10(1): 9942, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32555406

RESUMO

Cold-water coral (CWC) reefs are one of the most diverse and productive ecosystems in the deep sea. Especially in periods of seasonally-reduced phytodetritus food supply, their high productivity may depend on the recycling of resources produced on the reef, such as dissolved organic matter (DOM) and bacteria. Here, we demonstrate that abundant suspension feeders Geodia barretti (high-microbial-abundance sponge), Mycale lingua (low-microbial-abundance sponge) and Acesta excavata (bivalve) are able to utilize 13C-enriched (diatom-derived) DOM and bacteria for tissue growth and respiration. While DOM was an important potential resource for all taxa, utilization of bacteria was higher for the sponges as compared to the bivalve, indicating a particle-size differentiation among the investigated suspension feeders. Interestingly, all taxa released 13C-enriched particulate organic carbon, which in turn may feed the detritus pathway on the reef. Especially A. excavata produced abundant (pseudo-)fecal droppings. A second stable-isotope tracer experiment revealed that detritivorous ophiuroids utilized these droppings. The high resource flexibility of dominant reef suspension feeders, and the efficient recycling of their waste products by the detritivore community, may provide important pathways to maintain the high productivity on cold-water coral reefs, especially in periods of low external food supply.


Assuntos
Antozoários/crescimento & desenvolvimento , Bactérias/metabolismo , Radioisótopos de Carbono/metabolismo , Recifes de Corais , Ecossistema , Compostos Orgânicos/metabolismo , Água do Mar/microbiologia , Animais , Antozoários/metabolismo , Bactérias/classificação , Radioisótopos de Carbono/análise , Temperatura Baixa , Métodos de Alimentação , Água do Mar/química
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