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1.
BMC Infect Dis ; 24(1): 637, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926682

RESUMO

INTRODUCTION: Chronic lung disease is a major cause of morbidity in African children with HIV infection; however, the microbial determinants of HIV-associated chronic lung disease (HCLD) remain poorly understood. We conducted a case-control study to investigate the prevalence and densities of respiratory microbes among pneumococcal conjugate vaccine (PCV)-naive children with (HCLD +) and without HCLD (HCLD-) established on antiretroviral treatment (ART). METHODS: Nasopharyngeal swabs collected from HCLD + (defined as forced-expiratory-volume/second < -1.0 without reversibility postbronchodilation) and age-, site-, and duration-of-ART-matched HCLD- participants aged between 6-19 years enrolled in Zimbabwe and Malawi (BREATHE trial-NCT02426112) were tested for 94 pneumococcal serotypes together with twelve bacteria, including Streptococcus pneumoniae (SP), Staphylococcus aureus (SA), Haemophilus influenzae (HI), Moraxella catarrhalis (MC), and eight viruses, including human rhinovirus (HRV), respiratory syncytial virus A or B, and human metapneumovirus, using nanofluidic qPCR (Standard BioTools formerly known as Fluidigm). Fisher's exact test and logistic regression analysis were used for between-group comparisons and risk factors associated with common respiratory microbes, respectively. RESULTS: A total of 345 participants (287 HCLD + , 58 HCLD-; median age, 15.5 years [IQR = 12.8-18], females, 52%) were included in the final analysis. The prevalence of SP (40%[116/287] vs. 21%[12/58], p = 0.005) and HRV (7%[21/287] vs. 0%[0/58], p = 0.032) were higher in HCLD + participants compared to HCLD- participants. Of the participants positive for SP (116 HCLD + & 12 HCLD-), 66% [85/128] had non-PCV-13 serotypes detected. Overall, PCV-13 serotypes (4, 19A, 19F: 16% [7/43] each) and NVT 13 and 21 (9% [8/85] each) predominated. The densities of HI (2 × 104 genomic equivalents [GE/ml] vs. 3 × 102 GE/ml, p = 0.006) and MC (1 × 104 GE/ml vs. 1 × 103 GE/ml, p = 0.031) were higher in HCLD + compared to HCLD-. Bacterial codetection (≥ any 2 bacteria) was higher in the HCLD + group (36% [114/287] vs. (19% [11/58]), (p = 0.014), with SP and HI codetection (HCLD + : 30% [86/287] vs. HCLD-: 12% [7/58], p = 0.005) predominating. Viruses (predominantly HRV) were detected only in HCLD + participants. Lastly, participants with a history of previous tuberculosis treatment were more likely to carry SP (adjusted odds ratio (aOR): 1.9 [1.1 -3.2], p = 0.021) or HI (aOR: 2.0 [1.2 - 3.3], p = 0.011), while those who used ART for ≥ 2 years were less likely to carry HI (aOR: 0.3 [0.1 - 0.8], p = 0.005) and MC (aOR: 0.4 [0.1 - 0.9], p = 0.039). CONCLUSION: Children with HCLD + were more likely to be colonized by SP and HRV and had higher HI and MC bacterial loads in their nasopharynx. The role of SP, HI, and HRV in the pathogenesis of CLD, including how they influence the risk of acute exacerbations, should be studied further. TRIAL REGISTRATION: The BREATHE trial (ClinicalTrials.gov Identifier: NCT02426112 , registered date: 24 April 2015).


Assuntos
Infecções por HIV , Humanos , Estudos de Casos e Controles , Adolescente , Criança , Masculino , Feminino , Infecções por HIV/complicações , Infecções por HIV/microbiologia , Infecções por HIV/epidemiologia , Zimbábue/epidemiologia , Malaui/epidemiologia , Pneumopatias/microbiologia , Pneumopatias/virologia , Pneumopatias/epidemiologia , Adulto Jovem , Doença Crônica , Bactérias/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Vírus/isolamento & purificação , Vírus/classificação , Vírus/genética , Infecções Respiratórias/microbiologia , Infecções Respiratórias/virologia , Infecções Respiratórias/epidemiologia , Streptococcus pneumoniae/isolamento & purificação , Sistema Respiratório/microbiologia , Sistema Respiratório/virologia
2.
Eur J Heart Fail ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38887164

RESUMO

AIMS: Paradoxical low-flow, low-gradient aortic stenosis (pLFLG AS) may represent a diagnostic challenge, and its pathophysiology is complex. While left ventricular (LV) systolic function is preserved, right ventricular dysfunction (RVD) and consecutive LV underfilling may contribute to low-flow and reduced stroke volume index, and to adverse outcomes following transcatheter aortic valve implantation (TAVI). The aim of this study was to evaluate the potential role of RVD in pLFLG AS, and to assess the impact of pre-procedural RVD on clinical outcomes after TAVI in patients with pLFLG AS. METHODS AND RESULTS: Out of 2739 native AS patients, who received TAVI at the University of Cologne Heart Center between March 2013 and June 2021, 114 patients displayed pLFLG AS and were included in this study. Right ventricular (RV) function was assessed by transthoracic echocardiography, and a fractional area change (FAC) ≤35% and/or a tricuspid annular plane systolic excursion (TAPSE) <18 mm determined RVD. In addition, the TAPSE/systolic pulmonary artery pressure ratio (TAPSE/sPAP) was monitored as a measure of RV-pulmonary arterial (PA) coupling. An impaired FAC and TAPSE was present in 21.9% and 45.6% of patients, respectively, identifying RVD in 50.0%. RVD (p = 0.016), reduced FAC (p = 0.049), reduced TAPSE (p = 0.035) and impaired RV-PA coupling (TAPSE/sPAP ratio <0.31 mm/mmHg; p = 0.009) were associated with significantly higher all-cause mortality compared to patients with normal RV function. After adjustment for sex, age, body mass index, EuroSCORE II, previous myocardial infarction and mitral regurgitation, independent predictors for all-cause mortality were FAC, sPAP, TAPSE/sPAP ratio, right atrial area, RV diameter and tricuspid regurgitation. CONCLUSIONS: Adverse RV remodelling, RVD and impaired RV-PA coupling provide an explanation for low-flow and reduced stroke volume index in a subset of patients with pLFLG AS, and are associated with excess mortality after TAVI.

3.
Blood ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38838300

RESUMO

Immune thrombotic thrombocytopenic purpura (iTTP) is a rare, life-threatening autoimmune disorder caused by ADAMTS13 deficiency. Caplacizumab, an anti-VWF nanobody, is approved for iTTP treatment, reducing the need for therapeutic plasma exchange (TPE) and improving platelet count recovery and survival. We conducted a retrospective study on 42 acute iTTP cases in Austria and Germany, treated with a modified regimen aimed at avoiding TPE if platelet count increased after the first caplacizumab dose. Baseline characteristics and patient outcomes were compared with a control group of 59 patients with iTTP, receiving frontline treatment with TPE, caplacizumab, and immunosuppression. The main outcome was the time to platelet count normalization. Secondary outcomes included clinical response, exacerbation, refractory iTTP, iTTP-related deaths, and the time to platelet count doubling. The median time to platelet count normalization was similar between the two cohorts (3 and 4 days; P = 0.31). There were no significant differences in clinical response, exacerbations, refractoriness, iTTP-related deaths, or time to platelet count doubling reflecting the short-term treatment response. Four patients did not respond to the first caplacizumab dose and TPE was subsequently initiated. Cytomegalovirus infection, HIV/hepatitis B co-infection, an ovarian teratoma with associated anti-platelet antibodies, and multiple platelet transfusion before the correct diagnosis may have impeded immediate treatment response in these patients. In conclusion, caplacizumab and immunosuppression alone, without TPE, rapidly controlled thrombotic microangiopathy and achieved a sustained clinical response in iTTP. Our study provides a basis for TPE-free iTTP management in experienced centers via shared decision-making between patients and treating physicians.

4.
Gut ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834297

RESUMO

OBJECTIVE: Highly malignant pancreatic ductal adenocarcinoma (PDAC) is characterised by an abundant immunosuppressive and fibrotic tumour microenvironment (TME). Future therapeutic attempts will therefore demand the targeting of tumours and stromal compartments in order to be effective. Here we investigate whether dual specificity and tyrosine phosphorylation-regulated kinase 1B (DYRK1B) fulfil these criteria and represent a promising anticancer target in PDAC. DESIGN: We used transplantation and autochthonous mouse models of PDAC with either genetic Dyrk1b loss or pharmacological DYRK1B inhibition, respectively. Mechanistic interactions between tumour cells and macrophages were studied in direct or indirect co-culture experiments. Histological analyses used tissue microarrays from patients with PDAC. Additional methodological approaches included bulk mRNA sequencing (transcriptomics) and proteomics (secretomics). RESULTS: We found that DYRK1B is mainly expressed by pancreatic epithelial cancer cells and modulates the influx and activity of TME-associated macrophages through effects on the cancer cells themselves as well as through the tumour secretome. Mechanistically, genetic ablation or pharmacological inhibition of DYRK1B strongly attracts tumoricidal macrophages and, in addition, downregulates the phagocytosis checkpoint and 'don't eat me' signal CD24 on cancer cells, resulting in enhanced tumour cell phagocytosis. Consequently, tumour cells lacking DYRK1B hardly expand in transplantation experiments, despite their rapid growth in culture. Furthermore, combining a small-molecule DYRK1B-directed therapy with mammalian target of rapamycin inhibition and conventional chemotherapy stalls the growth of established tumours and results in a significant extension of life span in a highly aggressive autochthonous model of PDAC. CONCLUSION: In light of DYRK inhibitors currently entering clinical phase testing, our data thus provide a novel and clinically translatable approach targeting both the cancer cell compartment and its microenvironment.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38934146

RESUMO

The aim of the presented prospective observational study was to evaluate the effect of fistula flow on peripheral wave morphology and pulse wave velocity by means of the oscillometric Vicorder®-device with the purpose of fistula surveillance. METHODS: Digitized and normalized curves of 53 haemodialysis patients at the fistula and non-fistula arm were analyzed. Slope parameters and the areas under the curve of characteristic sections of pulse waves as well as the power spectrum of the pulse waves and their first and second derivatives were computed. Furthermore, the amplitude of volumetric change (AMP) was assessed. Duplex-sonography served as a reference method. RESULTS: In the comprehensive set of novel pulse wave parameters significant inter-arm differences were demonstrated and a significant delay of the systolic maximum at the fistula arm in comparison to the non-fistula arm (204 ± 3.4 versus 162 ± 5.3 ms, p<0.001) was proven. Unexpectedly, pulse wave velocity apparently did not differ between both arms (7.85 versus 8.05 m/sec at the fistula/non-fistula side, p=0.942). The inter-arm differences of the slope parameters were more pronounced in forearm than in upper arm fistulas. Finally, we showed that the inter-arm difference of AMP correlated with volume-flow (r= 0.326 with p=0.017). CONCLUSION: Pulse waves as assessed by oscillometric pulse wave analysis have distinct features at fistula and non-fistula arms. This is due to enhanced arteriovenous flow, i.e. in both the brachial artery and the fistula vein. The analysis of those alterations has the potential to assess fistula function.

6.
Appl Radiat Isot ; 210: 111362, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38810353

RESUMO

The double-differential cross-sections, and neutron yields of the 9Be(4He,n)12C and 12C(d,n)13N reactions at various energies, have been calculated. The cross-sections for the consider nuclear reactions were obtained using PHITS code based on Monte Carlo method. The calculated data were validated against the available experimental data with varying agreement up to 30MeV. We have suggested the most suitable reaction, at certain energies, for better neutron yield and hence radiotherapy applications.

7.
Front Cardiovasc Med ; 11: 1333749, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38812747

RESUMO

Background: During the SARS-CoV-2 pandemic it was speculated that the virus might be associated with a persistent increase of cardiovascular risk. The present study compares pre- and post-pandemic hospital admission rates for hypertension and coronary artery disease. Methods: Systematic multicentric retrospective cohort analysis of 57.795 hospital admissions in an urban region in Germany during two different periods (pre-pandemic 01-06/2019 vs. post-pandemic era 01-06/2023). Information on hospital admissions for arterial hypertension, chronic coronary syndrome, unstable angina pectoris and acute myocardial infarction were extracted from the hospitals data systems. Additionally, six comorbidities and performed coronary interventions were monitored. Results: Compared to the pre-pandemic era, there was no increase in hospitalizations for arterial hypertension (516 vs. 483, -6.8%, p = 0.07) or myocardial infarction (487 vs. 349, -23.8%, p < 0.001), but the total number of patient admissions with chest pain as the presenting symptom increased (chronic coronary syndrome: 759 vs. 943, +24.2%, p < 0.001; unstable angina pectoris: 270 vs. 451, +67.0%, p < 0.001). At the same time, the number of performed coronary angiographies increased, but less patients underwent percutaneous interventions. Patients admitted with chest pain in the post-pandemic era were in general healthier with less comorbidities. Conclusion: The present multicenter cohort study found no evidence for an increase in hospitalizations for arterial hypertension or coronary artery disease after the end of the pandemic. However, further studies with larger sample sizes are needed to confirm our results.

8.
Science ; 384(6693): eadl2528, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38452047

RESUMO

Deep-learning methods have revolutionized protein structure prediction and design but are presently limited to protein-only systems. We describe RoseTTAFold All-Atom (RFAA), which combines a residue-based representation of amino acids and DNA bases with an atomic representation of all other groups to model assemblies that contain proteins, nucleic acids, small molecules, metals, and covalent modifications, given their sequences and chemical structures. By fine-tuning on denoising tasks, we developed RFdiffusion All-Atom (RFdiffusionAA), which builds protein structures around small molecules. Starting from random distributions of amino acid residues surrounding target small molecules, we designed and experimentally validated, through crystallography and binding measurements, proteins that bind the cardiac disease therapeutic digoxigenin, the enzymatic cofactor heme, and the light-harvesting molecule bilin.


Assuntos
Aprendizado Profundo , Engenharia de Proteínas , Proteínas , Aminoácidos/química , Cristalografia , DNA/química , Modelos Moleculares , Proteínas/química , Engenharia de Proteínas/métodos
9.
J Hypertens ; 42(5): 777-782, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38372359

RESUMO

BACKGROUND: Sleep apnea is associated with hypertension. Metaanalyses indicate that treatment of sleep apnea by continuous positive airway pressure (CPAP) reduces blood pressure (BP) by a mean of 3 mmHg. To date, predictors of BP response to CPAP remain incompletely understood. We hypothesized that the magnitude of CPAP-induced BP reduction depends on baseline apnea-hypopnea index (AHI) and the extent of daytime sleepiness. METHODS: We performed a retrospective study on the association of BP response to CPAP with polysomnographic readings, intensity of sleepiness (measured by Epworth Sleepiness Scale, ESS), and epidemiologic parameters in 2461 patients with obstructive sleep apnea. BP response was defined as the difference between office BP at polysomonography examinations before and after initiation of CPAP. RESULTS: Five hundred and fifty-five patients fulfilled all inclusion and exclusion criteria and were included in the analysis. Median monthly CPAP usage was 143.7 h (85.4-204.1 h). BP was significantly higher at baseline than at follow-up (129.9 ±â€Š15.5 vs. 128.3 ±â€Š15.2, P  = 0.021) resulting in mean reduction of BP of -1.5 ±â€Š19.2 mmHg. patients with a higher than median baseline AHI (median 21) showed a more pronounced reduction of BP than those with lower AHI (AHI ≥21: 130.5 ±â€Š15.3 vs. 128.6 ±â€Š14.6, P  = 0.06; AHI <21: 129.5 ±â€Š15.8 vs. 127.9 ±â€Š15.8, P  = 0.18). CPAP therapy led to a significant reduction in sleepiness (8.3 ±â€Š4.8 vs. 6.6 ±â€Š4.5, P  < 0.0001). Those subjects with higher than median sleepiness score (ESS ≥8), however, did not show a significant difference in BP response compared with those with a lower sleepiness score. Receiver-operating characteristic (ROC) curve analyses investigating the accuracy of AHI and ESS to predict a BP reduction at least 5 mmHg revealed an AUC of 0.51 and 0.52, respectively. CONCLUSION: The study confirms that CPAP therapy for sleep apnea has a mild BP lowering effect. Although this effect is slightly higher in patients with above-average AHI, neither AHI nor ESS can be used to define threshold values predicting a BP decrease at least 5 mmHg.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Apneia Obstrutiva do Sono , Humanos , Pressão Sanguínea/fisiologia , Estudos Retrospectivos , Sonolência , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/terapia
10.
Diabetol Metab Syndr ; 16(1): 34, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38303090

RESUMO

BACKGROUND: Depression is associated with an increased risk for type 2 diabetes mellitus. However, depression may take different courses, and it is not fully understood how these affect the development of diabetes. It is further to be determined whether sex modifies the association between depression and type 2 diabetes. METHODS: We analyzed data from the Gutenberg Health Study, a longitudinal and population-based cohort study (N = 15,010) in Germany. Depressive symptoms (measured by PHQ-9), history of depression, diabetes mellitus, and relevant covariates were assessed at baseline, and the outcomes of prediabetes and type 2 diabetes mellitus were evaluated 5 years later. Logistic regression was used to estimate odds ratios of incident prediabetes and type 2 diabetes mellitus, adjusting for potential confounders as identified in a Directed Acyclic Graph. RESULTS: In the confounder adjusted model, current depression (PHQ-9 ≥ 10 at baseline; OR = 1.79, 95% CI = 1.11 to 2.74, p = 0.011), and persistent depression had a statistically significant (OR = 2.44, 95% CI = 1.62 to 3.54, p = 0.005) effect on incident type 2 diabetes mellitus. A history of depression without current depression had no statistically significant effect on type 2 diabetes (OR = 1.00, 95% CI = 0.68 to 1.43, p = 0.999). The effect of depression on incident diabetes did not differ significantly between women (OR = 2.02; 95% CI = 1.32 to 3.09) and men (OR = 2.16; 95% CI = 1.41 to 3.31; p-value for interaction on the multiplicative scale p = 0.832 and on the additive scale p = 0.149). Depression did not have a significant effect on incident prediabetes. CONCLUSION: This study shows how the history and trajectory of depression shape the risk for diabetes. This raises interesting questions on the cumulative effects of depression trajectories on diabetes and body metabolism in general. Depression can negatively affect physical health, contributing to increased morbidity and mortality in people with mental disorders.

11.
Invest Ophthalmol Vis Sci ; 65(1): 12, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38175640

RESUMO

Purpose: To investigate the longitudinal change in intraocular pressure (IOP) over 5 years and its relationship with cardiovascular parameters in a population-based sample in Germany. Methods: The Gutenberg Health Study is a prospective, observational, single-center cohort study. The sample was equally stratified for sex, residence, and age decade. IOP was measured with noncontact tonometry at baseline and at 5-year follow-up. Cardiovascular parameters, including body mass index (BMI), systolic blood pressure, and diabetes status, were assessed. Participants without IOP measurement at one time point, who were taking IOP-lowering medications, or who had ophthalmic surgery during the 5-year follow-up interval were excluded, as well as those with glaucoma diagnosis. Univariable and multivariable linear regression analyses were conducted. Results: This analysis included 9633 participants (48.9% female). The mean IOP increased from 14.04 ± 2.78 mmHg at baseline to 14.77 ± 2.92 mmHg at 5-year follow-up (P < 0.001). In multivariable linear regression analyses, an increase in BMI was associated with an increase in IOP over time (P < 0.001), whereas a higher baseline BMI was associated with a lower IOP change (P < 0.001). Higher age and male sex were associated with higher IOP change (P < 0.001). A change in systolic blood pressure was associated with IOP change, whereas baseline systolic blood pressure and diabetes status were not associated. Conclusions: This population-based study found a relationship between IOP change over 5 years and BMI and systolic blood pressure change, respectively. These findings suggest the importance of monitoring cardiovascular risk factors in IOP management.


Assuntos
Diabetes Mellitus , Glaucoma , Pressão Intraocular , Feminino , Humanos , Masculino , Estudos de Coortes , Estudos Prospectivos
12.
BMC Zool ; 9(1): 1, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38163865

RESUMO

BACKGROUND: Phasmatodea are well known for their ability to disguise themselves by mimicking twigs, leaves, or bark, and are therefore commonly referred to as stick and leaf insects. In addition to this and other defensive strategies, many phasmatodean species use paired prothoracic repellent glands to release defensive chemicals when disturbed by predators or parasites. These glands are considered as an autapomorphic trait of the Phasmatodea. However, detailed knowledge of the gland anatomy and chemical compounds is scarce and only a few species were studied until now. We investigated the repellent glands for a global sampling of stick and leaf insects that represents all major phasmatodean lineages morphologically via µCT scans and analyzed the anatomical traits in a phylogenetic context. RESULTS: All twelve investigated species possess prothoracic repellent glands that we classify into four distinct gland types. 1: lobe-like glands, 2: sac-like glands without ejaculatory duct, 3: sac-like glands with ejaculatory duct and 4: tube-like glands. Lobe-like glands are exclusively present in Timema, sac-like glands without ejaculatory duct are only found in Orthomeria, whereas the other two types are distributed across all other taxa (= Neophasmatodea). The relative size differences of these glands vary significantly between species, with some glands not exceeding in length the anterior quarter of the prothorax, and other glands extending to the end of the metathorax. CONCLUSIONS: We could not detect any strong correlation between aposematic or cryptic coloration of the examined phasmatodeans and gland type or size. We hypothesize that a comparatively small gland was present in the last common ancestor of Phasmatodea and Euphasmatodea, and that the gland volume increased independently in subordinate lineages of the Occidophasmata and Oriophasmata. Alternatively, the stem species of Neophasmatodea already developed large glands that were reduced in size several times independently. In any case, our results indicate a convergent evolution of the gland types, which was probably closely linked to properties of the chemical components and different predator selection pressures. Our study is the first showing the great anatomical variability of repellent glands in stick and leaf insects.

13.
Otol Neurotol ; 45(3): e214-e220, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38238925

RESUMO

HYPOTHESIS: The insertion angle of the electrode array has an influence on the perception of different musical features. BACKGROUND: A deeper insertion of the electrodes is associated with a greater coverage of the cochlea with possible stimulus locations. This could lead to an improved or extended perception of pitches and pitch changes as well as to a better perception of contours in musical pieces. METHODS: A Montreal Battery of Evaluation of Amusia test battery was conducted with a collective of 19 cochlear implant (CI) users and 9 normal-hearing subjects. For the CI users, the insertion angles of the intracochlear electrode arrays were calculated using Otoplan software. RESULTS: Compared with normal-hearing users, CI users performed worse in the detection of melodic features of music. CI users performed better with temporal features than with melodic features. An influence of the insertion depth of the electrodes on the results of the Montreal Battery of Evaluation of Amusia could be proven neither for Cochlear nor for MED-EL CI users. CONCLUSION: Deeper insertion of electrode arrays may only better approximate the spatial-frequency map. Alone, it does not have an effect on better detection and identification of pitch and tonality and, consequently, better perception of musical attributes. Anatomy-based calculation of electrode locations and matching to characteristic frequencies will be sought in subsequent studies.


Assuntos
Implante Coclear , Implantes Cocleares , Música , Humanos , Percepção da Altura Sonora , Implante Coclear/métodos , Cóclea
14.
Stroke ; 55(4): 1015-1024, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38275117

RESUMO

BACKGROUND: The dynamics of blood clot (combination of Hb [hemoglobin], fibrin, and a higher concentration of aggregated red blood cells) formation within the hematoma of an intracerebral hemorrhage is not well understood. A quantitative neuroimaging method of localized coagulated blood volume/distribution within the hematoma might improve clinical decision-making. METHODS: The deoxyhemoglobin of aggregated red blood cells within extravasated blood exhibits a higher magnetic susceptibility due to unpaired heme iron electrons. We propose that coagulated blood, with higher aggregated red blood cell content, will exhibit (1) a higher positive susceptibility than noncoagulated blood and (2) increase in fibrin polymerization-restricted localized diffusion, which can be measured noninvasively using quantitative susceptibility mapping and diffusion tensor imaging. In this serial magnetic resonance imaging study, we enrolled 24 patients with acute intracerebral hemorrhage between October 2021 to May 2022 at a stroke center. Patients were 30 to 70 years of age and had a hematoma volume >15 cm3 and National Institutes of Health Stroke Scale score >1. The patients underwent imaging 3×: within 12 to 24 (T1), 36 to 48 (T2), and 60 to 72 (T3) hours of last seen well on a 3T magnetic resonance imaging system. Three-dimensional anatomic, multigradient echo and 2-dimensional diffusion tensor images were obtained. Hematoma and edema volumes were calculated, and the distribution of coagulation was measured by dynamic changes in the susceptibilities and fractional anisotropy within the hematoma. RESULTS: Using a coagulated blood phantom, we demonstrated a linear relationship between the percentage coagulation and susceptibility (R2=0.91) with a positive red blood cell stain of the clot. The quantitative susceptibility maps showed a significant increase in hematoma susceptibility (T1, 0.29±0.04 parts per millions; T2, 0.36±0.04 parts per millions; T3, 0.45±0.04 parts per millions; P<0.0001). A concomitant increase in fractional anisotropy was also observed with time (T1, 0.40±0.02; T2, 0.45±0.02; T3, 0.47±0.02; P<0.05). CONCLUSIONS: This quantitative neuroimaging study of coagulation within the hematoma has the potential to improve patient management, such as safe resumption of anticoagulants, the need for reversal agents, the administration of alteplase to resolve the clot, and the need for surgery.


Assuntos
Acidente Vascular Cerebral Hemorrágico , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral Hemorrágico/complicações , Imagem de Tensor de Difusão , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/complicações , Hemorragia Cerebral/complicações , Imageamento por Ressonância Magnética/métodos , Hematoma/complicações , Coagulação Sanguínea , Hemoglobinas , Fibrina
15.
Soft Matter ; 20(6): 1347-1360, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38252016

RESUMO

Despite the long history of investigations of polyelectrolyte multilayer formation on solid or liquid surfaces, important questions remain open concerning the construction of the first set of layers. These are generally deposited on a first anchoring layer of different chemistry, influencing their construction and properties. We propose here an in-depth investigation of the formation of NaPSS/PAH multilayers at the air/water interface in the absence of a chemically different anchoring layer, profiting from the surface activity of NaPSS. To analyse the mechanical properties of the different layers, we combine recently established analysis techniques of an inflating/deflating bubble exploiting simultaneous shape and pressure measurement: bubble shape elastometry, general stress decomposition and capillary meniscus dynanometry. We complement these measurements by interfacial shear rheology. The obtained results allow us to confirm, first of all, the strength of the aforementioned techniques to characterize complex interfaces with non-linear viscoelastic properties. Furthermore, their sensitivity allows us to show that the multilayer properties are highly sensitive to the temporal and mechanical conditions under which they are constructed and manipulated. We nevertheless identify a robust trend showing a clear transition from a liquid-like viscoelastic membrane to a solid-like viscoelastic membrane after the deposition of 5 layers. We interpret this as the number of layers required to create a fully connected multilayer, which is consistent with previous results obtained on solid or liquid interfaces.

16.
JAMA Pediatr ; 178(3): 304-306, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38227331

RESUMO

This case-control study investigates changes in microcirculation and endothelial function in the acute phase of multisystem inflammatory syndrome in children and 3 to 6 months after onset.


Assuntos
COVID-19 , Microcirculação , Síndrome de Resposta Inflamatória Sistêmica , Criança , Humanos , COVID-19/complicações
17.
Int J Gynaecol Obstet ; 164(1): 305-314, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37635683

RESUMO

OBJECTIVE: To evaluate blood-based biomarkers to detect endometriosis and/or adenomyosis across nine European centers (June 2014-April 2018). METHODS: This prospective, non-interventional study assessed the diagnostic accuracy of 54 blood-based biomarker immunoassays in samples from 919 women (aged 18-45 years) with suspicion of endometriosis and/or adenomyosis versus symptomatic controls. Endometriosis was stratified by revised American Society for Reproductive Medicine stage. Symptomatic controls were "pathologic symptomatic controls" or "pathology-free symptomatic controls". The main outcome measure was receiver operating characteristic-area under the curve (ROC-AUC) and Wilcoxon P values corrected for multiple testing (q values). RESULTS: CA-125 performed best in "all endometriosis cases" versus "all symptomatic controls" (AUC 0.645, 95% confidence interval [CI] 0.600-0.690, q < 0.001) and increased (P < 0.001) with disease stage. In "all endometriosis cases" versus "pathology-free symptomatic controls", S100-A12 performed best (AUC 0.692, 95% CI 0.614-0.769, q = 0.001) followed by CA-125 (AUC 0.649, 95% CI 0.569-0.729, q = 0.021). In "adenomyosis only cases" versus "symptomatic controls" or "pathology-free symptomatic controls", respectively, the top-performing biomarkers were sFRP-4 (AUC 0.615, 95% CI 0.551-0.678, q = 0.045) and S100-A12 (AUC 0.701, 95% CI 0.611-0.792, q = 0.004). CONCLUSION: This study concluded that no biomarkers tested could diagnose or rule out endometriosis/adenomyosis with high certainty.


Assuntos
Adenomiose , Endometriose , Feminino , Humanos , Endometriose/diagnóstico , Adenomiose/diagnóstico , Adenomiose/patologia , Estudos Prospectivos , Curva ROC , Biomarcadores
18.
Nat Chem ; 16(2): 210-217, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37945834

RESUMO

Microscopic sequences of synthetic polymers play crucial roles in the polymer properties, but are generally unknown and inaccessible to traditional measurements. Here we report real-time optical sequencing of single synthetic copolymer chains under living polymerization conditions. We achieve this by carrying out multi-colour imaging of polymer growth by single catalysts at single-monomer resolution using CREATS (coupled reaction approach toward super-resolution imaging). CREATS makes a reaction effectively fluorogenic, enabling single-molecule localization microscopy of chemical reactions at higher reactant concentrations. Our data demonstrate that the chain propagation kinetics of surface-grafted polymerization contains temporal fluctuations with a defined memory time (which can be attributed to neighbouring monomer interactions) and chain-length dependence (due to surface electrostatic effects). Furthermore, the microscopic sequences of individual copolymers reveal their tendency to form block copolymers, and, more importantly, quantify the size distribution of individual blocks for comparison with theoretically random copolymers. Such sequencing capability paves the way for single-chain-level structure-function correlation studies of synthetic polymers.

19.
Heart Rhythm ; 21(4): 362-369, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38040404

RESUMO

BACKGROUND: Atrial fibrillation (AF) is the most common heart arrhythmia and considered to be a progressive chronic disease associated with increased morbidity and mortality. Recent data suggest a link between inflammation, oxidative stress, and AF, although the underlying mechanisms are not fully understood. Because oxidized lipoproteins cause structural damage and electrophysiologic changes in cardiomyocytes, it is feasible that the transformation of atheroprotective high-density lipoprotein (HDL) into dysfunctional HDL contributes to the development of AF. OBJECTIVE: The purpose of this study was to determine whether a reduced antioxidant function of HDL is associated with the presence of AF. METHODS: In this multicenter cross-sectional cohort study, we assessed HDL function in sera of 1206 participants. Patients were divided into groups according to the presence of AF (n = 233) or no AF (n = 973). A validated cell-free biochemical assay was used to determine reduced HDL antioxidant function as assessed by increased normalized HDL lipid peroxide content (nHDLox). RESULTS: Participants with AF had a 9% higher mean relative nHDLox compared to persons without AF (P = .025). nHDLox was strongly associated with AF in all models of logistic regression, including the analysis adjusted for age, sex, and risk factors for AF (all P ≤.01). CONCLUSION: Reduced antioxidant HDL function is associated with the presence of AF, which supports growing evidence that impaired lipoprotein function is linked to electrophysiological changes in cardiomyocytes. nHDLox is one of several contributors to the initiation and perpetuation of AF.


Assuntos
Fibrilação Atrial , Lipoproteínas HDL , Humanos , Lipoproteínas HDL/metabolismo , Fibrilação Atrial/etiologia , Antioxidantes/metabolismo , Estudos Transversais , Estresse Oxidativo
20.
Photodiagnosis Photodyn Ther ; 45: 103906, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38042235

RESUMO

Tuberculosis (TB), a bacterial infection caused by Mycobacterium tuberculosis, is highly contagious and can lead to severe health complications if left untreated. This review article discusses the importance of early detection and treatment and its global incidence and epidemiology, emphasizing its impact on vulnerable populations and its role as a major cause of death worldwide. Furthermore, it highlights the challenges faced with diagnosing TB. To overcome these challenges, point-of-care devices have emerged as promising tools for rapid and accurate TB detection. These include devices such as nucleic acid amplification tests (NAATs), lateral flow assays (LFAs), and microfluidic-based assays, which offer advantages such as rapid results, portability, and the ability to detect drug-resistant strains. Optical-based devices, such as photonic micro-ring sensors, silicon platform-based sensors, plasmonic-based platforms, microfluidics, and smartphone imaging, are some of the highlighted optical-based devices with the potential to detect TB. These devices can detect TB in sputum samples with high sensitivity and specificity. Optical-based diagnostic devices have the potential to offer the advantages of detecting low concentrations of target molecules and being adaptable to detect multiple targets simultaneously. Using these devices in a clinical setting makes them suitable for their application in improving access to diagnostic testing that enables earlier detection and treatment of TB. Furthermore, these devices would improve TB's global health issue, which requires comprehensive research, prevention, and treatment efforts.


Assuntos
Dispositivos Ópticos , Fotoquimioterapia , Tuberculose , Humanos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes , Tuberculose/diagnóstico , Cabeça
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