Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 109
Filtrar
1.
Proc (Bayl Univ Med Cent) ; 37(6): 903-907, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39440081

RESUMO

Background: The primary aim of our study was to determine which patient characteristics were associated with opioid consumption following cesarean delivery. Methods: The Baylor Scott & White Research Institute institutional review board approved this study (024-178). Patients who underwent cesarean delivery at Baylor Scott & White Medical Center - Temple with single injection or combined spinal epidural anesthesia in 2023 were eligible for inclusion. We examined the medical records of 300 patients, calculated the 24-hour opioid consumption for each, and compared the top third to the low group in a bivariate analysis and then performed a multivariate logistic regression. Results: One hundred thirty-one patients had no opioid consumption in the first 24 postoperative hours, and 100 patients had a morphine milligram consumption of 30 to 117.5 mg. A multivariate logistic regression determined that patients in the higher opioid consumption cohort were more likely to have received combined spinal epidural anesthesia (odds ratio 2.079; 95% confidence interval 1.149, 3.762; P = 0.02) and administration of intravenous dexmedetomidine in the intraoperative period (odds ratio 2.542; 95% confidence interval 1.038, 6.224; P = 0.04). Conclusion: Intraoperative administration of intravenous dexmedetomidine and combined spinal epidural anesthesia was associated with increased postoperative opioid consumption following cesarean delivery.

2.
Am Heart J ; 278: 83-92, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39216691

RESUMO

BACKGROUND: Despite improved survival, hospitalization is still common among patients with heart failure (HF). OBJECTIVE: This study aimed to examine temporal trends in infection-related hospitalization among HF patients and compare it to temporal trends in the risk of HF hospitalization and death. METHODS: Using Danish nationwide registers, we included all patients aged 18 to 100 years, with HF diagnosed between January 1, 1997 and December 31, 2017, resulting in a total population of 147.737 patients. The outcomes of interest were primarily infection-related hospitalization and HF hospitalization and secondarily all-cause mortality. The Aalen Johansen's estimator was used to estimate 5-year absolute risks for the primary outcomes. Additionally, cox analysis was used for adjusted analyses. RESULTS: The population had a median age of 74 [64, 82] years and 57.6 % were males. Patients with HF had a higher risk of infection over time 16.4 % (95% CI 16.0-16.8) in 1997 to 2001 vs 24.5% (95% CI 24.0-24.9) in 2012 to 2017. In contrast, they had a lower risk of HF hospitalization 26.5% (95% CI 26.1-27.0) in 1997 to 2001 vs 23.2% (95% CI 22.8-23.7) in 2012 to 2017. The risk of infection stratified by infection type showed similar trends for all infection types and marked the risk of pneumonia infection as the most significant in all subintervals. CONCLUSION: In the period from 1997 to 2017, we observed patients with HF had an increased risk of infection-related hospitalization, driven by pneumonia infections. In contrast, the risk of HF hospitalization decreased over time.

3.
Environ Sci Atmos ; 4(7): 740-753, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39006766

RESUMO

Isoprene affects new particle formation rates in environments and experiments also containing monoterpenes. For the most part, isoprene reduces particle formation rates, but the reason is debated. It is proposed that due to its fast reaction with OH, isoprene may compete with larger monoterpenes for oxidants. However, by forming a large amount of peroxy-radicals (RO2), isoprene may also interfere with the formation of the nucleating species compared to a purely monoterpene system. We explore the RO2 cross reactions between monoterpene and isoprene oxidation products using the radical Volatility Basis Set (radical-VBS), a simplified reaction mechanism, comparing with observations from the CLOUD experiment at CERN. We find that isoprene interferes with covalently bound C20 dimers formed in the pure monoterpene system and consequently reduces the yields of the lowest volatility (Ultra Low Volatility Organic Carbon, ULVOC) VBS products. This in turn reduces nucleation rates, while having less of an effect on subsequent growth rates.

4.
Stem Cell Res Ther ; 15(1): 144, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38764077

RESUMO

BACKGROUND: The aim of this study was to evaluate potential synergistic effects of a single, local application of human umbilical cord MSC-derived sEVs in combination with a low dose of recombinant human rhBMP-2 to promote the regeneration of a metaphyseal femoral defect in an osteoporotic rat model. METHODS: 6 weeks after induction of osteoporosis by bilateral ventral ovariectomy and administration of a special diet, a total of 64 rats underwent a distal femoral metaphyseal osteotomy using a manual Gigli wire saw. Defects were stabilized with an adapted Y-shaped mini-locking plate and were subsequently treated with alginate only, or alginate loaded with hUC-MSC-sEVs (2 × 109), rhBMP-2 (1.5 µg), or a combination of sEVs and rhBMP-2 (n = 16 for each group). 6 weeks post-surgery, femora were evaluated by µCT, descriptive histology, and biomechanical testing. RESULTS: Native radiographs and µCT analysis confirmed superior bony union with callus formation after treatment with hUC-MSC-sEVs in combination with a low dose of rhBMP-2. This finding was further substantiated by histology, showing robust defect consolidation 6 weeks after treatment. Torsion testing of the explanted femora revealed increased stiffness after application of both, rhBMP-2 alone, or in combination with sEVs, whereas torque was only significantly increased after treatment with rhBMP-2 together with sEVs. CONCLUSION: The present study demonstrates that the co-application of hUC-MSC-sEVs can improve the efficacy of rhBMP-2 to promote the regeneration of osteoporotic bone defects.


Assuntos
Proteína Morfogenética Óssea 2 , Vesículas Extracelulares , Fêmur , Osteoporose , Proteínas Recombinantes , Cordão Umbilical , Animais , Proteína Morfogenética Óssea 2/farmacologia , Proteína Morfogenética Óssea 2/genética , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/genética , Osteoporose/patologia , Ratos , Feminino , Humanos , Fêmur/patologia , Fêmur/efeitos dos fármacos , Fêmur/diagnóstico por imagem , Cordão Umbilical/citologia , Vesículas Extracelulares/metabolismo , Regeneração Óssea/efeitos dos fármacos , Ratos Sprague-Dawley , Fator de Crescimento Transformador beta/farmacologia , Modelos Animais de Doenças , Microtomografia por Raio-X , Células-Tronco Mesenquimais/metabolismo
5.
Environ Sci Atmos ; 4(5): 531-546, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38764888

RESUMO

Iodine oxoacids are recognised for their significant contribution to the formation of new particles in marine and polar atmospheres. Nevertheless, to incorporate the iodine oxoacid nucleation mechanism into global simulations, it is essential to comprehend how this mechanism varies under various atmospheric conditions. In this study, we combined measurements from the CLOUD (Cosmic Leaving OUtdoor Droplets) chamber at CERN and simulations with a kinetic model to investigate the impact of temperature, ionisation, and humidity on iodine oxoacid nucleation. Our findings reveal that ion-induced particle formation rates remain largely unaffected by changes in temperature. However, neutral particle formation rates experience a significant increase when the temperature drops from +10 °C to -10 °C. Running the kinetic model with varying ionisation rates demonstrates that the particle formation rate only increases with a higher ionisation rate when the iodic acid concentration exceeds 1.5 × 107 cm-3, a concentration rarely reached in pristine marine atmospheres. Consequently, our simulations suggest that, despite higher ionisation rates, the charged cluster nucleation pathway of iodic acid is unlikely to be enhanced in the upper troposphere by higher ionisation rates. Instead, the neutral nucleation channel is likely to be the dominant channel in that region. Notably, the iodine oxoacid nucleation mechanism remains unaffected by changes in relative humidity from 2% to 80%. However, under unrealistically dry conditions (below 0.008% RH at +10 °C), iodine oxides (I2O4 and I2O5) significantly enhance formation rates. Therefore, we conclude that iodine oxoacid nucleation is the dominant nucleation mechanism for iodine nucleation in the marine and polar boundary layer atmosphere.

6.
J Am Heart Assoc ; 13(6): e032539, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38471834

RESUMO

BACKGROUND: The incidence and distribution of acute and chronic dialysis among patients with heart failure (HF), stratified by diabetes, remain uncertain. We hypothesized that with improved survival and rising comorbidities, the demand for dialysis would increase over time. METHODS AND RESULTS: Patients with incident HF, aged 18 to 100 years, between 2002 and 2016, were identified using Danish nationwide registers. Primary outcomes included acute and chronic dialysis initiation, HF-related hospitalization, and all-cause mortality. These outcomes were assessed in 2002 to 2006, 2007 to 2011, and 2012 to 2016, stratified by diabetes. We calculated incidence rates (IRs) per 1000 person-years and hazard ratios (HR) using multivariable Cox regression. Of 115 533 patients with HF, 2734 patients received acute dialysis and 1193 patients received chronic dialysis. The IR was 8.0 per 1000 and 3.5 per 1000 person-years for acute and chronic dialysis, respectively. Acute dialysis rates increased significantly among patients with diabetes over time, while no significant changes occurred in those without diabetes, chronic dialysis, HF-related hospitalization, or overall mortality. Diabetes was associated with significantly higher HRs of acute and chronic dialysis, respectively, compared with patients without diabetes (HR, 2.07 [95% CI, 1.80-2.39] and 2.93 [95% CI, 2.40-3.58] in 2002 to 2006; HR, 2.45 [95% CI, 2.14-2.80] and 2.86 [95% CI, 2.32-3.52] in 2007 to 2011; and 2.69 [95% CI, 2.33-3.10] and 3.30 [95% CI, 2.69-4.06] in 2012 to 2016). CONCLUSIONS: The IR of acute and chronic dialysis remained low compared with HF-related hospitalizations and mortality. Acute dialysis rates increased significantly over time, contrasting no significant trends in other outcomes. Diabetes exhibited over 2-fold increased rates of the outcomes. These findings emphasize the importance of continued monitoring and renal care in patients with HF, especially with diabetes, to optimize outcomes and prevent adverse events.


Assuntos
Diabetes Mellitus , Insuficiência Cardíaca , Humanos , Diálise Renal/efeitos adversos , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia , Insuficiência Cardíaca/etiologia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia , Hospitalização , Comorbidade
7.
Environ Sci Atmos ; 4(2): 265-274, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38371605

RESUMO

Aerosols formed and grown by gas-to-particle processes are a major contributor to smog and haze in megacities, despite the competition between growth and loss rates. Rapid growth rates from ammonium nitrate formation have the potential to sustain particle number in typical urban polluted conditions. This process requires supersaturation of gas-phase ammonia and nitric acid with respect to ammonium nitrate saturation ratios. Urban environments are inhomogeneous. In the troposphere, vertical mixing is fast, and aerosols may experience rapidly changing temperatures. In areas close to sources of pollution, gas-phase concentrations can also be highly variable. In this work we present results from nucleation experiments at -10 °C and 5 °C in the CLOUD chamber at CERN. We verify, using a kinetic model, how long supersaturation is likely to be sustained under urban conditions with temperature and concentration inhomogeneities, and the impact it may have on the particle size distribution. We show that rapid and strong temperature changes of 1 °C min-1 are needed to cause rapid growth of nanoparticles through ammonium nitrate formation. Furthermore, inhomogeneous emissions of ammonia in cities may also cause rapid growth of particles.

8.
Mol Genet Genomic Med ; 12(1): e2286, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37968878

RESUMO

BACKGROUND: Safe transfusion therapy requires accurate testing of blood donors and recipients to determine their ABO blood group compatibility. Genotyping does not always clarify serological blood typing discrepancies and conventional PCR methods are not suitable to identify ABO haplotypes. Therefore, an allele-specific long-range sequencing-based typing method was established. METHODS: Study samples (n = 100) and six patient samples were ABO phenotyped and screened for specific single nucleotide polymorphisms (SNP) in the ABO gene. Based on identified heterozygous SNPs in intron 1 (12897G>A), 2 (437C>T) or 4 (102C>A, 1511G>T) both ABO alleles were investigated separately using a high-fidelity long-range PCR system and Sanger sequencing. The alleles were correlated to the ABO phenotypes determined. RESULTS: Direct sequencing of allelic PCR products up to 6743 bases has been successful in discriminating common combinations of the ABO*A1.01, ABO*A2.01, ABO*B.01, ABO*O.01.01, ABO*O.01.02 and ABO*O.02.01 alleles. 10 out of 64 haplotypes were found to be not previously described. The uncommon ABO*AW.31.01 and the unusual O alleles ABO*O.05 and ABO*O.02.03 alleles were detected in patient samples, resolving the initial inconclusive serologic ABO typing results. CONCLUSION: This method is an effective tool for analyzing ABO haplotypes. Applicable for ABO molecular diagnostics and immunohematology research it may help to improve pre-transfusion blood type testing.


Assuntos
Sistema ABO de Grupos Sanguíneos , Humanos , Alelos , Haplótipos , Genótipo , Fenótipo , Sistema ABO de Grupos Sanguíneos/genética
9.
Sci Adv ; 9(36): eadi5297, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37682996

RESUMO

Biogenic vapors form new particles in the atmosphere, affecting global climate. The contributions of monoterpenes and isoprene to new particle formation (NPF) have been extensively studied. However, sesquiterpenes have received little attention despite a potentially important role due to their high molecular weight. Via chamber experiments performed under atmospheric conditions, we report biogenic NPF resulting from the oxidation of pure mixtures of ß-caryophyllene, α-pinene, and isoprene, which produces oxygenated compounds over a wide range of volatilities. We find that a class of vapors termed ultralow-volatility organic compounds (ULVOCs) are highly efficient nucleators and quantitatively determine NPF efficiency. When compared with a mixture of isoprene and monoterpene alone, adding only 2% sesquiterpene increases the ULVOC yield and doubles the formation rate. Thus, sesquiterpene emissions need to be included in assessments of global aerosol concentrations in pristine climates where biogenic NPF is expected to be a major source of cloud condensation nuclei.

10.
J Clin Periodontol ; 50(10): 1305-1314, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37464548

RESUMO

AIM: To investigate the association between previous periodontal treatment and recurrent events after first-time myocardial infarction (MI). MATERIALS AND METHODS: From the Danish nationwide registries, patients with first-time MI between 2000 and 2015 were divided into three groups according to oral health care within 1 year prior to first-time MI. A multiple logistic regression model provided adjusted odds ratios (ORs) with 95% confidence intervals (CIs) to assess the 3-year risk of major adverse cardiovascular events (MACE). RESULTS: A total of 103,949 patients were included. Patients with treated periodontitis (PD) prior to first-time MI had an adjusted 3-year risk of MACE similar to patients presumed periodontally healthy (OR 0.97 [95% CI 0.92-1.03]). Patients with no prior dental visits were significantly older, had more comorbidities and showed significantly increased adjusted 3-year risks of MACE (OR 1.47 [95% CI 1.42-1.52]), cardiovascular death (OR 1.71 [95% CI 1.64-1.78]) and heart failure (OR 1.13 [95% CI 1.07-1.20]) compared with patients presumed periodontally healthy. CONCLUSIONS: Patients with treated PD 1 year prior to first-time MI had a similar risk of recurrent cardiovascular events as patients presumed periodontally healthy. No dental visit prior to first-time MI was an independent risk factor for recurrent events.


Assuntos
Infarto do Miocárdio , Periodontite , Humanos , Estudos de Coortes , Infarto do Miocárdio/complicações , Infarto do Miocárdio/epidemiologia , Fatores de Risco , Periodontite/complicações , Periodontite/epidemiologia , Periodontite/terapia , Dinamarca/epidemiologia
11.
J Neurooncol ; 164(1): 97-105, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37477823

RESUMO

PURPOSE: Effective chemotherapeutical agents for the treatment of meningiomas are still lacking. Previous in-vitro analyses revealed efficacy of decitabine (DCT), a DNA methyltransferase (DNMT) inhibitor established in the treatment of leukemia, in a yet undefined subgroup of meningiomas. METHODS: Effects of DCT on proliferation and viability was analyzed in primary meningioma cells by immunofluorescence and MTT assays, and cases were classified as drug responders and non-responders. Molecular preconditions for efficacy were analyzed using immunofluorescence for Ki67, DNMT1, and five oncogenes (TRIM58, FAM84B, ELOVL2, MAL2, LMO3) previously found to be differentially methylated after DCT exposition, as well as by genome-wide DNA methylation analyses. RESULTS: Efficacy of DCT (10µM) was found in eight (62%) of 13 meningioma cell lines 48 h after drug exposition (p < .05). DCT significantly reduced DNMT1 expression in all but two cell lines, and median ΔDNMT1 reduction 48 h after drug exposition was lower in DCT-resistant (-11.1%) than in DCT-sensitive (-50.5%, p = .030) cells. Rates of cell lines responsive to DCT exposition distinctly decreased to 25% after 72 h. No significant correlation of the patients´ age, sex, histological subtype, location of the paternal tumor, expression of Ki67, DNMT1 or the analyzed oncogenes with treatment response was found (p > .05, each). DCT efficacy was further independent of the methylation class and global DNA methylation of the paternal tumor. CONCLUSION: Early effects of DCT in meningiomas are strongly related with DNMT1 expression, while clinical, histological, and molecular predictors for efficacy are sparse. Kinetics of drug efficacy might indicate necessity of repeated exposition and encourage further analyses.


Assuntos
Neoplasias Meníngeas , Meningioma , Humanos , Decitabina/farmacologia , Decitabina/uso terapêutico , Azacitidina/farmacologia , Azacitidina/uso terapêutico , Meningioma/tratamento farmacológico , Meningioma/genética , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Projetos Piloto , Antígeno Ki-67/metabolismo , Inibidores Enzimáticos/farmacologia , Neoplasias Meníngeas/tratamento farmacológico , Neoplasias Meníngeas/genética , Metilação de DNA , Linhagem Celular Tumoral , Proteínas Proteolipídicas Associadas a Linfócitos e Mielina/genética , Proteínas Proteolipídicas Associadas a Linfócitos e Mielina/metabolismo
12.
Nat Commun ; 14(1): 3347, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37291087

RESUMO

The interaction between nitrogen monoxide (NO) and organic peroxy radicals (RO2) greatly impacts the formation of highly oxygenated organic molecules (HOM), the key precursors of secondary organic aerosols. It has been thought that HOM production can be significantly suppressed by NO even at low concentrations. Here, we perform dedicated experiments focusing on HOM formation from monoterpenes at low NO concentrations (0 - 82 pptv). We demonstrate that such low NO can enhance HOM production by modulating the RO2 loss and favoring the formation of alkoxy radicals that can continue to autoxidize through isomerization. These insights suggest that HOM yields from typical boreal forest emissions can vary between 2.5%-6.5%, and HOM formation will not be completely inhibited even at high NO concentrations. Our findings challenge the notion that NO monotonically reduces HOM yields by extending the knowledge of RO2-NO interactions to the low-NO regime. This represents a major advance towards an accurate assessment of HOM budgets, especially in low-NO environments, which prevails in the pre-industrial atmosphere, pristine areas, and the upper boundary layer.


Assuntos
Atmosfera , Óxido Nítrico , Monoterpenos , Oxirredução , Aerossóis
13.
Bioengineering (Basel) ; 10(3)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36978729

RESUMO

The aim of this current study was to establish a metaphyseal femoral non-union model in osteoporotic rats by comparing a power tool versus a manual tool for fracture creation. Twelve adult female Sprague Dawley rats were ovariectomized (OVX) and received a special diet for 6 weeks. Biweekly pQCT measurements confirmed a significant reduction in the cancellous and total bone mineral density in OVX rats compared to control (CTRL) animals. After 6 weeks, OVX rats underwent surgery creating a distal metaphyseal osteotomy, either using a piezoelectric- (n = 6) or a manual Gigli wire (n = 6) saw. Fractures were stabilized with a Y-shaped mini-locking plate. Within each group, three rats received Alginate directly into the fracture gap. OVX animals gained more weight over 8 weeks compared to CTRL animals. pQCT analysis showed a significant difference in the volumetric cancellous bone mineral density between OVX and CTRL rats. A histological examination of the osteoporotic phenotype was completed. Radiographic evaluation and Masson-Goldner trichrome staining with the piezoelectric saw failed to demonstrate bony bridging or a callus formation. New bone formation and complete healing were seen after 6 weeks in the Gigli group. For the creation of a metaphyseal atrophic non-union in the osteoporotic bone, a piezoelectric saw should be used.

14.
Am J Sports Med ; 51(2): 331-342, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36645050

RESUMO

BACKGROUND: Despite significant advancements in surgical techniques to repair rotator cuff (RC) injuries, failure rates remain high and novel approaches to adequately overcome the natural biological limits of tendon and enthesis regeneration of the RC are required. Small extracellular vesicles (sEVs) derived from the secretome of human multipotent mesenchymal stromal cells (MSCs) have been demonstrated to modulate inflammation and reduce fibrotic adhesions, and therefore their local application could improve outcomes after RC repair. PURPOSE: In this pilot study, we evaluated the efficacy of clinical-grade human umbilical cord (hUC) MSC-derived sEVs (hUC-MSC-sEVs) loaded onto a type 1 collagen scaffold in an ovine model of acute infraspinatus tendon injury to improve RC healing. STUDY DESIGN: Controlled laboratory study. METHODS: sEVs were enriched from hUC-MSC culture media and were characterized by surface marker profiling. The immunomodulatory capacity was evaluated in vitro by T-cell proliferation assays, and particle count was determined by nanoparticle tracking analysis. Twelve skeletally mature sheep were subjected to partial infraspinatus tenotomy and enthesis debridement. The defects of 6 animals were treated with 2 × 1010 hUC-MSC-sEVs loaded onto a type 1 collagen sponge, whereas 6 animals received only a collagen sponge, serving as controls. Six weeks postoperatively, the healing of the infraspinatus tendon and the enthesis was evaluated by magnetic resonance imaging (MRI) and hard tissue histology. RESULTS: CD3/CD28-stimulated T-cell proliferation was significantly inhibited by hUC-MSC-sEVs (P = .015) that displayed the typical surface marker profile, including the presence of the MSC marker proteins CD44 and melanoma-associated chondroitin sulfate proteoglycan. The local application of hUC-MSC-sEVs did not result in any marked systemic adverse events. Histologically, significantly improved Watkins scores (P = .031) indicated improved tendon and tendon-to-bone insertion repair after sEV treatment and lower postcontrast signal of the tendon and adjacent structures on MRI suggested less residual inflammation at the defect area. Furthermore, the formation of osteophytes at the injury site was significantly attenuated (P = .037). CONCLUSION: A local, single-dose application of hUC-MSC-sEVs promoted tendon and enthesis healing in an ovine model of acute RC injury. CLINICAL RELEVANCE: Surgical repair of RC tears generally results in a clinical benefit for the patient; however, considerable rerupture rates have been reported. sEVs have potential as a cell-free biotherapeutic to improve healing outcomes after RC injury.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Lesões do Manguito Rotador , Animais , Ovinos , Humanos , Manguito Rotador/cirurgia , Projetos Piloto , Colágeno Tipo I/metabolismo , Lesões do Manguito Rotador/cirurgia , Células-Tronco Mesenquimais/metabolismo , Vesículas Extracelulares/patologia , Cordão Umbilical
15.
Cancers (Basel) ; 15(1)2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36612300

RESUMO

Background: The usefulness of 5-ALA-mediated fluorescence-guided resection (FGR) in meningiomas is controversial, and information on the molecular background of fluorescence is sparse. Methods: Specimens obtained during 44 FGRs of intracranial meningiomas were analyzed for the presence of tumor tissue and fluorescence. Protein/mRNA expression of key transmembrane transporters/enzymes involved in PpIX metabolism (ABCB6, ABCG2, FECH, CPOX) were investigated using immunohistochemistry/qPCR. Results: Intraoperative fluorescence was observed in 70 of 111 specimens (63%). No correlation was found between fluorescence and the WHO grade (p = 0.403). FGR enabled the identification of neoplastic tissue (sensitivity 84%, specificity 67%, positive and negative predictive value of 86% and 63%, respectively, AUC: 0.75, p < 0.001), and was improved in subgroup analyses excluding dura specimens (86%, 88%, 96%, 63% and 0.87, respectively; p < 0.001). No correlation was found between cortical fluorescence and tumor invasion (p = 0.351). Protein expression of ABCB6, ABCG2, FECH and CPOX was found in meningioma tissue and was correlated with fluorescence (p < 0.05, each), whereas this was not confirmed for mRNA expression. Aberrant expression was observed in the CNS. Conclusion: FGR enables the intraoperative identification of meningioma tissue with limitations concerning dura invasion and due to ectopic expression in the CNS. ABCB6, ABCG2, FECH and CPOX are expressed in meningioma tissue and are related to fluorescence.

16.
Nat Chem ; 15(1): 129-135, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36376388

RESUMO

Iodine is a reactive trace element in atmospheric chemistry that destroys ozone and nucleates particles. Iodine emissions have tripled since 1950 and are projected to keep increasing with rising O3 surface concentrations. Although iodic acid (HIO3) is widespread and forms particles more efficiently than sulfuric acid, its gas-phase formation mechanism remains unresolved. Here, in CLOUD atmospheric simulation chamber experiments that generate iodine radicals at atmospherically relevant rates, we show that iodooxy hypoiodite, IOIO, is efficiently converted into HIO3 via reactions (R1) IOIO + O3 → IOIO4 and (R2) IOIO4 + H2O → HIO3 + HOI + (1)O2. The laboratory-derived reaction rate coefficients are corroborated by theory and shown to explain field observations of daytime HIO3 in the remote lower free troposphere. The mechanism provides a missing link between iodine sources and particle formation. Because particulate iodate is readily reduced, recycling iodine back into the gas phase, our results suggest a catalytic role of iodine in aerosol formation.


Assuntos
Iodatos , Iodo , Aerossóis
17.
Environ Sci Atmos ; 2(3): 491-499, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35694134

RESUMO

Intense new particle formation events are regularly observed under highly polluted conditions, despite the high loss rates of nucleated clusters. Higher than expected cluster survival probability implies either ineffective scavenging by pre-existing particles or missing growth mechanisms. Here we present experiments performed in the CLOUD chamber at CERN showing particle formation from a mixture of anthropogenic vapours, under condensation sinks typical of haze conditions, up to 0.1 s-1. We find that new particle formation rates substantially decrease at higher concentrations of pre-existing particles, demonstrating experimentally for the first time that molecular clusters are efficiently scavenged by larger sized particles. Additionally, we demonstrate that in the presence of supersaturated gas-phase nitric acid (HNO3) and ammonia (NH3), freshly nucleated particles can grow extremely rapidly, maintaining a high particle number concentration, even in the presence of a high condensation sink. Such high growth rates may explain the high survival probability of freshly formed particles under haze conditions. We identify under what typical urban conditions HNO3 and NH3 can be expected to contribute to particle survival during haze.

18.
Neurosurg Rev ; 45(4): 2767-2775, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35445910

RESUMO

Treatment of meningiomas refractory to surgery and irradiation is challenging and effective chemotherapies are still lacking. Recently, in vitro analyses revealed decitabine (DCT, 5-aza-2'-deoxycytidine) to be effective in high-grade meningiomas and, moreover, to induce hypomethylation of distinct oncogenes only sparsely described in meningiomas in vivo yet.Expression of the corresponding onco- and tumor suppressor genes TRIM58, FAM84B, ELOVL2, MAL2, LMO3, and DIO3 were analyzed and scored by immunohistochemical staining and RT-PCR in samples of 111 meningioma patients. Correlations with clinical and histological variables and prognosis were analyzed in uni- and multivariate analyses.All analyzed oncogenes were highly expressed in meningiomas. Expression scores of TRIM58 tended to be higher in benign than in high-grade tumors 20 vs 16 (p = .002) and all 9 samples lacking TRIM58 expression displayed WHO grade II/III histology. In contrast, median expression scores for both FAM84B (6 vs 4, p ≤ .001) and ELOVL2 (9 vs 6, p < .001) were increased in high-grade as compared to benign meningiomas. DIO3 expression was distinctly higher in all analyzed samples as compared to the reference decitabine-resistant Ben-Men 1 cell line. Increased ELOVL2 expression (score ≥ 8) correlated with tumor relapse in both uni- (HR: 2.42, 95%CI 1.18-4.94; p = .015) and multivariate (HR: 2.09, 95%CI 1.01-4.44; p = .046) analyses.All oncogenes involved in DCT efficacy in vitro are also widely expressed in vivo, and expression is partially associated with histology and prognosis. These results strongly encourage further analyses of DCT efficiency in meningiomas in vitro and in situ.


Assuntos
Neoplasias Meníngeas , Meningioma , Decitabina/farmacologia , Decitabina/uso terapêutico , Humanos , Neoplasias Meníngeas/tratamento farmacológico , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/patologia , Meningioma/tratamento farmacológico , Meningioma/genética , Meningioma/patologia , Recidiva Local de Neoplasia , Oncogenes , Prognóstico
19.
EBioMedicine ; 75: 103778, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35007819

RESUMO

BACKGROUND: Treatment of degenerating tendons still presents a major challenge, since the aetiology of tendinopathies remains poorly understood. Besides mechanical overuse, further known predisposing factors include rheumatoid arthritis, diabetes, obesity or smoking all of which combine with a systemic inflammation. METHODS: To determine whether the systemic inflammation accompanying these conditions contributes to the onset of tendinopathy, we studied the effect of a systemic inflammation induced by an allergic episode on tendon properties. To this end, we induced an allergic response in mice by exposing them to a timothy grass pollen allergen and subsequently analysed both their flexor and Achilles tendons. Additionally, we analysed data from a health survey comprising data from more than 10.000 persons for an association between the occurrence of an allergy and tendinopathy. FINDINGS: Biomechanical testing and histological analysis revealed that tendons from allergic mice not only showed a significant reduction of both elastic modulus and tensile stress, but also alterations of the tendon matrix. Moreover, treatment of 3D tendon-like constructs with sera from allergic mice resulted in a matrix-remodelling expression profile and the expression of macrophage-associated markers and matrix metalloproteinase 2 (MMP2) was increased in allergic Achilles tendons. Data from the human health study revealed that persons suffering from an allergy have an increased propensity to develop a tendinopathy. INTERPRETATION: Our study demonstrates that the presence of a systemic inflammation accompanying an allergic condition negatively impacts on tendon structure and function. FUNDING: This study was financially supported by the Fund for the Advancement of Scientific Research at Paracelsus Medical University (PMU-FFF E-15/22/115-LEK), by the Land Salzburg, the Salzburger Landeskliniken (SALK, the Health Care Provider of the University Hospitals Landeskrankenhaus and Christian Doppler Klinik), the Paracelsus Medical University, Salzburg and by unrestricted grants from Bayer, AstraZeneca, Sanofi-Aventis, Boehringer-Ingelheim.


Assuntos
Tendão do Calcâneo , Hipersensibilidade , Tendinopatia , Tendão do Calcâneo/patologia , Animais , Humanos , Hipersensibilidade/complicações , Hipersensibilidade/patologia , Inflamação/patologia , Metaloproteinase 2 da Matriz , Camundongos , Tendinopatia/etiologia , Tendinopatia/patologia
20.
FASEB J ; 36(2): e22126, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35044682

RESUMO

Vascular endothelial growth factor (VEGF) signaling is crucial for a large variety of cellular processes, not only related to angiogenesis but also in nonvascular cell types. We have previously shown that controlling angiogenesis by reducing VEGF-A signaling positively affects tendon healing. We now hypothesize that VEGF signaling in non-endothelial cells may contribute to tendon pathologies. By immunohistochemistry we show that VEGFR1, VEGFR2, and VEGFR3 are expressed in murine and human tendon cells in vivo. In a rat Achilles tendon defect model we show that VEGFR1, VEGFR3, and VEGF-D expression are increased after injury. On cultured rat tendon cells we show that VEGF-D stimulates cell proliferation in a dose-dependent manner; the specific VEGFR3 inhibitor SAR131675 reduces cell proliferation and cell migration. Furthermore, activation of VEGFR2 and -3 in tendon-derived cells affects the expression of mRNAs encoding extracellular matrix and matrix remodeling proteins. Using explant model systems, we provide evidence, that VEGFR3 inhibition prevents biomechanical deterioration in rat tail tendon fascicles cultured without load and attenuates matrix damage if exposed to dynamic overload in a bioreactor system. Together, these results suggest a strong role of tendon cell VEGF signaling in mediation of degenerative processes. These findings give novel insight into tendon cell biology and may pave the way for novel treatment options for degenerative tendon diseases.


Assuntos
Tendão do Calcâneo/metabolismo , Transdução de Sinais/fisiologia , Fator D de Crescimento do Endotélio Vascular/metabolismo , Animais , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Matriz Extracelular/metabolismo , Feminino , Humanos , Masculino , Camundongos , Neovascularização Patológica/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos Lew , Ratos Sprague-Dawley , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA