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2.
Front Pharmacol ; 15: 1338333, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38482058

RESUMEN

Diabetes remains an important disease worldwide with about 500 million patients globally. In tropical Africa, Morus mesozygia is traditionally used in the treatment of diabetes. Biological and phytochemical investigation of the root bark extracts of the plant led to the isolation of a new prenylated arylbenzofuran named 7-(3-hydroxy-3-methylbutyl)moracin M (1) and two congeners, moracins P (2) and M (3). When compared to acarbose (IC50 = 486 µM), all the isolated compounds are better inhibitors of α-glucosidase with in vitro IC50 values of 16.9, 16.6, and 40.9 µM, respectively. However, they were not active against α-amylase. The compounds also demonstrated moderate inhibition of dipeptidyl peptidase-4 (DPP4). Based on in silico docking studies, all isolates (1, 2, and 3) exhibit binding affinities of -8.7, -9.5, and -8.5 kcal/mol, respectively against α-glucosidase enzyme (PDB: 3AJ7). They are stabilized within the α-glucosidase active site through hydrogen bonds, pi interactions, and hydrophobic interactions. This study provides scientific support for the traditional use of Morus mesozygia in the treatment of diabetes as well as adding to the repository of α-glucosidase inhibitory agents.

3.
Sci Rep ; 14(1): 3128, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38326378

RESUMEN

Continuous monitoring of volcanic gas emissions is crucial for understanding volcanic activity and potential eruptions. However, emissions of volcanic gases underwater are infrequently studied or quantified. This study explores the potential of Distributed Acoustic Sensing (DAS) technology to monitor underwater volcanic degassing. DAS converts fiber-optic cables into high-resolution vibration recording arrays, providing measurements at unprecedented spatio-temporal resolution. We conducted an experiment at Laacher See volcano in Germany, immersing a fiber-optic cable in the lake and interrogating it with a DAS system. We detected and analyzed numerous acoustic signals that we associated with bubble emissions in different lake areas. Three types of text-book bubbles exhibiting characteristic waveforms are all found from our detections, indicating different nucleation processes and bubble sizes. Using clustering algorithms, we classified bubble events into four distinct clusters based on their temporal and spectral characteristics. The temporal distribution of the events provided insights into the evolution of gas seepage patterns. This technology has the potential to revolutionize underwater degassing monitoring and provide valuable information for studying volcanic processes and estimating gas emissions. Furthermore, DAS can be applied to other applications, such as monitoring underwater carbon capture and storage operations or methane leaks associated with climate change.

4.
Angew Chem Int Ed Engl ; 63(15): e202318362, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38294139

RESUMEN

We present the multiple post-modification of organic macrocycles and cages, introducing functional groups into two- and three-dimensional supramolecular scaffolds bearing fluorine substituents, which opens up new possibilities in multi-step supramolecular chemistry employing the vast chemical space of readily available isocyanates. The mechanism and scope of the reaction that proceeds after isocyanate addition to the benzylamine motif via an azadefluorination cyclisation (ADFC) were investigated using DFT calculations, and a series of aromatic isocyanates with different electronic properties were tested. The compounds show excellent chemical stability and were fully characterised. They can be used for subsequent cross-coupling reactions, and ADFC can be used directly to generate cross-linked membranes from macrocycles or cages when using ditopic isocyanates. Single-crystal X-ray (SC-XRD) analysis shows the proof of the formation of the desired supramolecular entity together with the connectivity predicted by calculations and from 19F NMR shifts, allowing the late-stage functionalisation of self-assembled macrocycles and cages by ADFC.

5.
Int J Mol Sci ; 24(21)2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37958488

RESUMEN

Aristotelia chilensis or "maqui" is a tree native to Chile used in the folk medicine of the Mapuche people as an anti-inflammatory agent for the treatment of digestive ailments, fever, and skin lesions. Maqui fruits are black berries which are considered a "superfruit" with notable potential health benefits, promoted to be an antioxidant, cardioprotective, and anti-inflammatory. Maqui leaves contain non-iridoid monoterpene indole alkaloids which have previously been shown to act on nicotinic acetylcholine receptors, potassium channels, and calcium channels. Here, we isolated a new alkaloid from maqui leaves, now called makomakinol, together with the known alkaloids aristoteline, hobartine, and 3-formylindole. Moreover, the polyphenols quercetine, ethyl caffeate, and the terpenes, dihydro-ß-ionone and terpin hydrate, were also obtained. In light of the reported analgesic and anti-nociceptive properties of A. chilensis, in particular a crude mixture of alkaloids containing aristoteline and hobartinol (PMID 21585384), we therefore evaluated the activity of aristoteline and hobartine on NaV1.8, a key NaV isoform involved in nociception, using automated whole-cell patch-clamp electrophysiology. Aristoteline and hobartine both inhibited Nav1.8 with an IC50 of 68 ± 3 µM and 54 ± 1 µM, respectively. Hobartine caused a hyperpolarizing shift of the voltage-dependence of the activation, whereas aristoteline did not change the voltage-dependence of the activation or inactivation. The inhibitory activity of these alkaloids on NaV channels may contribute to the reported analgesic properties of Aristotelia chilensis used by the Mapuche people.


Asunto(s)
Alcaloides , Elaeocarpaceae , Humanos , Alcaloides/farmacología , Alcaloides Indólicos , Extractos Vegetales/farmacología , Analgésicos/farmacología , Antiinflamatorios
6.
Chempluschem ; 88(12): e202300353, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37638597

RESUMEN

The utilisation of light to achieve precise manipulation and control over the structure and function of supramolecular assemblies has emerged as a highly promising approach in the development of complex, configurable, or multifunctional systems and nanoscopic machine-like entities. In this minireview, we highlight recent examples of self-assembled and covalently bound cages and macrocycles with a focus on the external and internal functionalisation of a structure with a photoswitchable unit or the embedment of a photoswitch into the framework of a structure. Functionalising the interior or exterior of a supramolecular cage or macrocycle with a photoresponsive group enables control over different properties, such as guest binding or assembly in the solid-state, while the overall shape of the assembly often undergoes no significant change. By directly integrating a photoswitchable unit into the framework of a supramolecular structure, the isomerisation can either induce a geometry change, the disassembly, or the disassembly and reassembly of the structure. Historical and recent examples covered in this review are based on azobenzene, diarylethene, stilbene photoswitches, or alkene motors that were incorporated into macrocycles and cages constructed by metal-organic, dynamic covalent, or covalent bonds.

7.
ERJ Open Res ; 9(4)2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37609599

RESUMEN

Introduction: Endoscopic lung volume reduction (ELVR) with one-way valves produces beneficial outcomes in patients with severe emphysema. Evidence on the efficacy remains unclear in patients with a very low forced expiratory volume in 1 s (FEV1) (≤20% predicted). We aim to compare clinical outcomes of ELVR, in relation to the FEV1 restriction. Methods: All data originated from the German Lung Emphysema Registry (Lungenemphysem Register), which is a prospective multicentric observational study for patients with severe emphysema after lung volume reduction. Two groups were formed at baseline: FEV1 ≤20% pred and FEV1 21-45% pred. Pulmonary function tests (FEV1, residual volume, partial pressure of carbon dioxide), training capacity (6-min walk distance (6MWD)), quality of life (modified Medical Research Council dyspnoea scale (mMRC), COPD Assessment Test (CAT), St George's Respiratory Questionnaire (SGRQ)) and adverse events were assessed and compared at baseline and after 3 and 6 months. Results: 33 patients with FEV1 ≤20% pred and 265 patients with FEV1 21-45% pred were analysed. After ELVR, an increase in FEV1 was observed in both groups (both p<0.001). The mMRC and CAT scores, and 6MWD improved in both groups (all p<0.05). The SGRQ score improved significantly in the FEV1 21-45% pred group, and by trend in the FEV1 ≤20% pred group. Pneumothorax was the most frequent complication within the first 90 days in both groups (FEV1 ≤20% pred: 7.7% versus FEV1 21-45% pred: 22.1%; p=0.624). No deaths occurred in the FEV1 ≤20% pred group up to 6 months. Conclusion: Our study highlights the potential efficacy of one-way valves, even in patients with very low FEV1, as these patients experienced significant improvements in FEV1, 6MWD and quality of life. No death was reported, suggesting a good safety profile, even in these high-risk patients.

8.
Diagnostics (Basel) ; 13(13)2023 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-37443525

RESUMEN

Notwithstanding some improvement in the earlier detection of patients with lung cancer, most of them still present with a late-stage disease at the time of diagnosis. Next to the most frequently utilized factors affecting the prognosis of lung cancer patients (stage, performance, and age), the recent application of biomarkers obtained by liquid profiling has gained more acceptance. In our study, we aimed to answer these questions: (i) Is the quantification of free-circulating methylated PTGER4 and SHOX2 plasma DNA a useful method for therapy monitoring, and is this also possible for patients treated with different therapy regimens? (ii) Is this approach possible when blood-drawing tubes, which allow for a delayed processing of blood samples, are utilized? Baseline values for mPTGER4 and mSHOX2 do not allow for clear discrimination between different response groups. In contrast, the combination of the methylation values for both genes shows a clear difference between responders vs. non-responders at the time of re-staging. Furthermore, blood drawing into tubes stabilizing the sample allows researchers more flexibility.

9.
J Nat Prod ; 86(6): 1520-1528, 2023 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-37253120

RESUMEN

Ficucaricone D (1) and its 4'-demethyl congener 2 are isoflavones isolated from fruits of Ficus carica that share a 5,7-dimethoxy-6-prenyl-substituted A-ring. Both natural products were, for the first time, obtained by chemical synthesis in six steps, starting from 2,4,6-trihydroxyacetophenone. Key steps are a microwave-promoted tandem sequence of Claisen- and Cope-rearrangements to install the 6-prenyl substituent and a Suzuki-Miyaura cross coupling for installing the B-ring. By using various boronic acids, non-natural analogues become conveniently available. All compounds were tested for cytotoxicity against drug-sensitive and drug-resistant human leukemia cell lines, but were found to be inactive. The compounds were also tested for antimicrobial activities against a panel of eight Gram-negative and two Gram-positive bacterial strains. Addition of the efflux pump inhibitor phenylalanine-arginine-ß-naphthylamide (PAßN) significantly improved the antibiotic activity in most cases, with MIC values as low as 2.5 µM and activity improvement factors as high as 128-fold.


Asunto(s)
Ficus , Isoflavonas , Humanos , Ficus/química , Isoflavonas/farmacología , Isoflavonas/química , Antibacterianos/farmacología , Línea Celular
10.
Chronic Obstr Pulm Dis ; 10(3): 211-223, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37140947

RESUMEN

Introduction: Patients with chronic obstructive pulmonary disease (COPD) have an increased risk of acquiring severe coronavirus disease 2019 (COVID-19), which is why self-isolation was recommended. However, long periods of social isolation, accompanied by limited access to health care systems, might influence the outcome of patients with severe COPD negatively. Methods: Data from COPD and pneumonia patients at Charité-Universitätsmedizin Berlin and the volume of endoscopic lung volume reduction (ELVR) surgeries from the German Lung Emphysema Registry (Lungenemphysem Register e.V.) were analyzed from pre-pandemic (2012 to 2019) to the pandemic period (2020 and 2021). In addition, 52 patients with COPD Global initiative for chronic Obstructive Lung Disease (GOLD) stage 4 status included in the lung emphysema registry received questionnaires during lockdowns from June 2020 to April 2021. Results: Admissions and ventilation therapies administered to COPD patients significantly decreased during the COVID-19 pandemic. Likewise, there was a reduction in ELVR treatments and follow-ups registered in German emphysema centers. Mortality was slightly higher among patients hospitalized with COPD during the pandemic. Increasing proportions of COPD patients with GOLD stage 3 and GOLD stage 4 status reported behavioral changes and subjective feelings of increasing COPD symptoms the longer the lockdown lasted. However, COPD symptom questionnaires revealed stable COPD symptoms over the pandemic time period. Summary: This study reveals reduced COPD admissions and elective treatment procedures of COPD patients during the pandemic, but a slight increase in mortality among patients hospitalized with COPD, irrespective of COVID-19. Correspondingly, patients with severe COPD reported subjective deterioration of their health status, probably caused by their very strict compliance with lockdown measures.

11.
Eur J Nucl Med Mol Imaging ; 50(7): 2140-2151, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36820890

RESUMEN

BACKGROUND: In patients with non-small cell lung cancer (NSCLC), accuracy of [18F]FDG-PET/CT for pretherapeutic lymph node (LN) staging is limited by false positive findings. Our aim was to evaluate machine learning with routinely obtainable variables to improve accuracy over standard visual image assessment. METHODS: Monocentric retrospective analysis of pretherapeutic [18F]FDG-PET/CT in 491 consecutive patients with NSCLC using an analog PET/CT scanner (training + test cohort, n = 385) or digital scanner (validation, n = 106). Forty clinical variables, tumor characteristics, and image variables (e.g., primary tumor and LN SUVmax and size) were collected. Different combinations of machine learning methods for feature selection and classification of N0/1 vs. N2/3 disease were compared. Ten-fold nested cross-validation was used to derive the mean area under the ROC curve of the ten test folds ("test AUC") and AUC in the validation cohort. Reference standard was the final N stage from interdisciplinary consensus (histological results for N2/3 LNs in 96%). RESULTS: N2/3 disease was present in 190 patients (39%; training + test, 37%; validation, 46%; p = 0.09). A gradient boosting classifier (GBM) with 10 features was selected as the final model based on test AUC of 0.91 (95% confidence interval, 0.87-0.94). Validation AUC was 0.94 (0.89-0.98). At a target sensitivity of approx. 90%, test/validation accuracy of the GBM was 0.78/0.87. This was significantly higher than the accuracy based on "mediastinal LN uptake > mediastinum" (0.7/0.75; each p < 0.05) or combined PET/CT criteria (PET positive and/or LN short axis diameter > 10 mm; 0.68/0.75; each p < 0.001). Harmonization of PET images between the two scanners affected SUVmax and visual assessment of the LNs but did not diminish the AUC of the GBM. CONCLUSIONS: A machine learning model based on routinely available variables from [18F]FDG-PET/CT improved accuracy in mediastinal LN staging compared to established visual assessment criteria. A web application implementing this model was made available.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/patología , Mediastino/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Fluorodesoxiglucosa F18 , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Metástasis Linfática/diagnóstico por imagen , Metástasis Linfática/patología , Estudios Retrospectivos , Ganglios Linfáticos/patología , Estadificación de Neoplasias
12.
Chemistry ; 29(18): e202300079, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-36715238

RESUMEN

We report the formation of metal-organic cage-crosslinked polymer hydrogels. To enable crosslinking of the cages and subsequent network formation, we used homodifunctionalized poly(ethylene glycol) (PEG) chains terminally substituted with bipyridines as ligands for the Pd6 L4 corners. The encapsulation of guest molecules into supramolecular self-assembled metal-organic cage-crosslinked hydrogels, as well as ultrasound-induced disassembly of the cages with release of their cargo, is presented in addition to their characterization by nuclear magnetic resonance (NMR) techniques, rheology, and comprehensive small-angle X-ray scattering (SAXS) experiments. The constrained geometries simulating external force (CoGEF) method and barriers using a force-modified potential energy surface (FMPES) suggest that the cage-opening mechanism starts with the dissociation of one pyridine ligand at around 0.5 nN. We show the efficient sonochemical activation of the hydrogels HG3 -6 , increasing the non-covalent guest-loading of completely unmodified drugs available for release by a factor of ten in comparison to non-crosslinked, star-shaped assemblies in solution.

13.
J Org Chem ; 88(3): 1649-1664, 2023 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-36633349

RESUMEN

Isoflavones were synthesized via Suzuki-Miyaura coupling of 3-iodochromones and para-methoxybenzene- and para-phenolboronic acid. In our hands, conditions commonly used for similar cross couplings turned out to be unsuccessful or difficult to reproduce, for example, due to the unplanned partial cleavage of MOM-protecting groups. Using Pd(dba)2 as a precatalyst and tricyclohexylphosphine as an activating ligand, reliable cross-coupling conditions were identified. In all cases, notably higher yields of isoflavones were obtained with para-phenolboronic acid than with para-methoxybenzene boronic acid. This observation and the commercial availability of para-phenolboronic acid suggest that for the synthesis of the important 3'-prenyl- or 3',5'-diprenylisoflavone substitution pattern a synthetic route that introduces the prenyl substituents after the Pd-catalyzed cross-coupling step, thereby avoiding laborious and protecting-group-intensive multistep syntheses of C-prenylated arene boronic acids, is advantageous.


Asunto(s)
Isoflavonas , Paladio , Catálisis , Ácidos Borónicos
14.
Int J Mol Sci ; 23(21)2022 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-36361785

RESUMEN

Fungal biotransformation is an attractive synthetic strategy to produce highly specific compounds with chemical functionality in regions of the carbon skeleton that are not easily activated by conventional organic chemistry methods. In this work, Cladosporium antarcticum isolated from sediments of Glacier Collins in Antarctica was used to obtain novel drimane sesquiterpenoids alcohols with activity against Candida yeast from drimendiol and epidrimendiol. These compounds were produced by the high-yield reduction of polygodial and isotadeonal with NaBH4 in methanol. Cladosporium antarcticum produced two major products from drimendiol, identified as 9α-hydroxydrimendiol (1, 41.4 mg, 19.4% yield) and 3ß-hydroxydrimendiol (2, 74.8 mg, 35% yield), whereas the biotransformation of epidrimendiol yielded only one product, 9ß-hydroxyepidrimendiol (3, 86.6 mg, 41.6% yield). The products were purified by column chromatography and their structure elucidated by NMR and MS. The antifungal activity of compounds 1-3 was analyzed against Candida albicans, C. krusei and C. parapsilosis, showing that compound 2 has a MIC lower than 15 µg/mL against the three-pathogenic yeast. In silico studies suggest that a possible mechanism of action for the novel compounds is the inhibition of the enzyme lanosterol 14α-demethylase, affecting the ergosterol synthesis.


Asunto(s)
Alcoholes , Sesquiterpenos , Alcoholes/metabolismo , Candida , Antifúngicos/química , Sesquiterpenos/química , Candida albicans , Biotransformación , Pruebas de Sensibilidad Microbiana
15.
Int J Mol Sci ; 23(19)2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-36233069

RESUMEN

Drimys winteri J.R. (Winteraceae) produce drimane sesquiterpenoids with activity against Candida yeast. In this work, drimenol, polygodial (1), isotadeonal (2), and a new drimane α,ß-unsaturated 1,4-dialdehyde, named winterdial (4), were purified from barks of D. winteri. The oxidation of drimenol produced the monoaldehyde drimenal (3). These four aldehyde sesquiterpenoids were evaluated against six Candida species isolated from candidemia patients in Chilean hospitals. Results showed that 1 displays fungistatic activity against all yeasts (3.75 to 15.0 µg/mL), but irritant effects on eyes and skin, whereas its non-pungent epimer 2 has fungistatic and fungicide activities at 1.9 and 15.0 µg/mL, respectively. On the other hand, compounds 3 and 4 were less active. Molecular dynamics simulations suggested that compounds 1-4 are capable of binding to the catalytic pocket of lanosterol 14-alpha demethylase with similar binding free energies, thus suggesting a potential mechanism of action through the inhibition of ergosterol synthesis. According to our findings, compound 2 appears as a valuable molecular scaffold to pursue the future development of more potent drugs against candidiasis with fewer side effects than polygodial. These outcomes are significant to broaden the alternatives to treat fungal infections with increasing prevalence worldwide using natural compounds as a primary source for active compounds.


Asunto(s)
Candidemia , Fungicidas Industriales , Sesquiterpenos , Aldehídos/farmacología , Candida , Chile , Ergosterol , Humanos , Irritantes , Lanosterol , Sesquiterpenos Policíclicos , Sesquiterpenos/química
16.
Angew Chem Int Ed Engl ; 61(48): e202212745, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36165240

RESUMEN

Visible light can be used to shift dynamic covalent imine assemblies out of equilibrium. We studied a fluorinated azobenzene building block that reliably undergoes geometric isomerism upon irradiation. The building block was used in combination with two different amines, ethylenediamine and R,R-1,2-diaminocyclohexane, to create a library of imine macrocycles. Whereas the simple amine can be used to access a polymeric state and a defined bowl-shaped macrocycle, the chiral amine gives access to a rich network of macrocycles that undergo both isomerisation as well as interconversion between different macrocyclic species, thereby allowing for control over the number of monomers involved in the cyclo-oligomerization; 1 H- and 19 F-DOSY NMR, MALDI-MS measurements, and UV/Vis spectroscopy were used to study the processes.

17.
Lung Cancer ; 170: 165-175, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35803041

RESUMEN

INTRODUCTION: Local ablative therapy (LAT) improves survival in oligometastatic lung cancer (OMD), but there is limited information on recurrence patterns, re-treatments and in particular the role of brain metastases during the course of disease. We therefore conducted a retrospective multicenter analysis to evaluate course of disease, sequence of therapies and predictors for long-term disease-control in the brain and survival endpoints. PATIENTS AND METHODS: Clinical data of patients with synchronous, single organ OMD with ≤4 metastases were collected from 5 certified German lung cancer centers. All patients underwent thorough initial staging including a 18FDG-PET/CT scan, brain imaging and mediastinal staging, if necessary, and received LAT to all sites of disease. RESULTS: In total, 164 patients were included (median age 62 years [range 41-84], non-squamous histology 80%, N0-1 64%, single metastasis 84%), 103 had brain (cohort A), 61 extracranial metastases (cohort B). With a median follow-up of 66 months, 115 patients (70%) experienced recurrent disease with a different distribution of sites: In cohort A vs. B, brain relapses occurred in 56% vs. 18% and new distant metastases in 5% vs. 40%. In total, LAT for every relapse was possible for 25% (29/115) of the patients. Patients with initial and secondary onset brain metastases experienced long-term disease-control in the brain and subsequently favorable survival with the application of repeated LAT (disease in the brain controlled vs. not-controlled, HR 0.21, p < 0.001). Comparable long-term overall survival was observed in patients with no or isolated brain relapses (5-years OS 74% and 92%) in contrast to patients with extracranial relapses (5-years OS 19.6%, p < 0.001). CONCLUSIONS: Repeated LAT for recurrent synchronous single organ OMD results in a long-term favorable outcome. Disease control in the brain appears crucial and likely determines survival.


Asunto(s)
Neoplasias Encefálicas , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/secundario , Carcinoma de Pulmón de Células no Pequeñas/patología , Humanos , Neoplasias Pulmonares/patología , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Tomografía Computarizada por Tomografía de Emisión de Positrones , Estudios Retrospectivos , Resultado del Tratamiento
18.
Respiration ; 101(9): 823-832, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35785772

RESUMEN

BACKGROUND: Robust clinical evidence on the efficacy and safety of endoscopic lung volume reduction (ELVR) with one-way valves in patients with severe lung emphysema with chronic hypercapnic respiratory failure is lacking. OBJECTIVE: The aim of this study was to compare patient characteristics, clinical outcome measures, and incidences of adverse events between patients with severe COPD undergoing ELVR with one-way valves and with either a partial pressure of carbon dioxide (pCO2) of ≤45 mm Hg or with pCO2 >45 mm Hg. METHODS: This was a multicentre prospective study of patients with severe lung disease who were evaluated based on lung function, exercise capacity (6-min walk test [6-MWT]), and quality-of-life tests. RESULTS: Patients with pCO2 ≤45 mm Hg (n = 157) and pCO2 >45 mm Hg (n = 40) showed similar baseline characteristics. Patients with pCO2 ≤45 mm Hg demonstrated a significant increase in forced expiratory volume in 1 s (p < 0.001), a significant decrease in residual volume (RV) (p < 0.001), and significant improvements in the quality of life and 6-MWT at the 3-month follow-up. Patients with pCO2 >45 mm Hg had significant improvements in RV only (p < 0.05). There was a significant decrease in pCO2 between baseline and follow-up in hypercapnic patients, relative to the decrease in patients with pCO2 ≤45 mm Hg (p = 0.008). Patients who were more hypercapnic at baseline showed a greater reduction in pCO2 after valve placement (r = -0.38, p < 0.001). Pneumothorax was the most common adverse event in both groups. CONCLUSIONS: ELVR with one-way valves seems clinically beneficial with a remarkably good safety profile for patients with chronic hypercapnic respiratory failure.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica , Enfisema Pulmonar , Insuficiencia Respiratoria , Volumen Espiratorio Forzado , Humanos , Hipercapnia/etiología , Neumonectomía , Estudios Prospectivos , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/cirugía , Enfisema Pulmonar/complicaciones , Enfisema Pulmonar/cirugía , Calidad de Vida , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/cirugía , Resultado del Tratamiento
19.
Nat Prod Res ; 37(14): 2466-2471, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35707900

RESUMEN

Furofuran lignanes show important biological activities for the treatment of infectious diseases, inflammatory and metabolic pathologies. They have been isolated from leaves and barks of many plants. In Chile the native conifer Araucaria araucana produces eudesmin, matairesinol, secoisolariciresinol and lariciresinol in stemwood, branchwood and knotwood. These compounds were previously isolated by laborious flash chromatography on silica gel. Here we report the easy isolation of eudesmin by soxhlet extraction from milled knots of Araucaria araucana with hexane, followed by cryo-crystallization at -20 °C. Upon bromination of the isolated eudesmin epimerization at one benzylic position occurs, giving epieudesmin and the corresponding mono and di-brominated derivatives. The structures were determined by 1D, 2D NMR and X-ray diffraction. The analysis of products against Candida yeast showed that eudesmin has a moderate activity against different strains of Candida from 62.5 to 500 µg/mL. This activity decreases for epieudesmin, while bromine derivatives are not active.


Asunto(s)
Araucaria araucana , Bromo , Candida , Halogenación
20.
Materials (Basel) ; 15(8)2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35454500

RESUMEN

A catalyst-free Schiff base reaction was applied to synthesize two imine-linked covalent organic frameworks (COFs). The condensation reaction of 1,3,5-tris-(4-aminophenyl)triazine (TAPT) with 4,4'-biphenyldicarboxaldehyde led to the structure of HHU-COF-1 (HHU = Heinrich-Heine University). The fluorinated analog HHU-COF-2 was obtained with 2,2',3,3',5,5',6,6'-octafluoro-4,4'-biphenyldicarboxaldehyde. Solid-state NMR, infrared spectroscopy, X-ray photoelectron spectroscopy, and elemental analysis confirmed the successful formation of the two network structures. The crystalline materials are characterized by high Brunauer-Emmett-Teller surface areas of 2352 m2/g for HHU-COF-1 and 1356 m2/g for HHU-COF-2. The products of a larger-scale synthesis were applied to prepare mixed-matrix membranes (MMMs) with the polymer Matrimid. CO2/CH4 permeation tests revealed a moderate increase in CO2 permeability at constant selectivity for HHU-COF-1 as a dispersed phase, whereas application of the fluorinated COF led to a CO2/CH4 selectivity increase from 42 for the pure Matrimid membrane to 51 for 8 wt% of HHU-COF-2 and a permeability increase from 6.8 to 13.0 Barrer for the 24 wt% MMM.

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