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1.
Mod Pathol ; 37(5): 100465, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38460675

RESUMEN

Primary cutaneous follicle center lymphoma (PCFCL) has an excellent prognosis using local treatment, whereas nodal follicular lymphoma (nFL), occasionally presenting with cutaneous spread, often requires systemic therapy. Distinction of the 2 diseases based on histopathology alone might be challenging. Copy number alterations (CNAs) have scarcely been explored on a genome-wide scale in PCFCL; however, they might serve as potential biomarkers during differential diagnosis and risk stratification. Low-coverage whole-genome sequencing is a robust, high-throughput method for genome-wide copy number profiling. In this study, we analyzed 28 PCFCL samples from 20 patients and compared the copy number profiles with a cohort of diagnostic samples of 64 nFL patients. Although the copy number profile of PCFCL was similar to that of nFL, PCFCL lacked amplifications of 18q, with the frequency peaking at 18q21.33 in nFL cases involving the BCL2 locus (PCFCL: 5.0% vs nFL: 31.3%, P = .018, Fisher exact test). Development of distant cutaneous spread was significantly associated with higher genomic instability including the proportion of genome altered (0.02 vs 0.13, P = .033) and number of CNAs (2 vs 9 P = .017), as well as the enrichment of 2p22.2-p15 amplification involving REL and XPO1 (6.3% vs 60.0%, P = .005), 3q23-q24 amplification (0.0% vs 50.0%, P = .004), 6q16.1-q23.3 deletion (6.3% vs 50.0%, P = .018), and 9p21.3 deletion covering CDKN2A and CDKN2B loci (0.0% vs 40.0%, P = .014, all Fisher exact test) in PCFCL. Analysis of sequential tumor samples in 2 cases harboring an unfavorable clinical course pointed to the acquisition of 2p amplification in the earliest common progenitor underlining its pivotal role in malignant transformation. By performing genome-wide copy number profiling on the largest patient cohort to date, we identified distinctive CNA alterations conceivably facilitating the differential diagnosis of PCFCL and secondary cutaneous involvement of nFL and potentially aiding the risk stratification of patients with PCFCL in the future.


Asunto(s)
Variaciones en el Número de Copia de ADN , Linfoma Folicular , Neoplasias Cutáneas , Secuenciación Completa del Genoma , Humanos , Linfoma Folicular/genética , Linfoma Folicular/patología , Linfoma Folicular/diagnóstico , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/diagnóstico , Femenino , Masculino , Persona de Mediana Edad , Anciano , Diagnóstico Diferencial , Pronóstico , Adulto , Anciano de 80 o más Años , Biomarcadores de Tumor/genética
2.
Chemistry ; : e202401918, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38865343

RESUMEN

A series of a novel CAAC ligands featuring a spiro-fluorene group have been synthesized and complexed with ruthenium alkylidenes, yielding the corresponding Hoveyda-type derivatives as a new family of olefin metathesis catalysts. The novel complexes have been characterized by XRD, HRMS and NMR measurements. The synthetized complexes were tested in catalysis and showed good activity in olefin metathesis, as demonstrated on diethyl diallylmalonate and allyl acetate substrates. The unique backbone in the ligand system with the large, yet inflexible condensed system renders interesting properties to the catalyst, exemplified by the good catalytic performance and improved Z­selectivity. In addition, the complex can also serve as a hydrogenation catalyst in a consecutive (one-pot) reaction. The latter reaction can convert allyl acetate to butane­1,4­diol, a valuable chemical intermediate for biodegradable polybutylene succinate (PBS).

3.
Int J Mol Sci ; 25(1)2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38203849

RESUMEN

Highly sulfated malto-oligomers, similar to heparin and heparan-sulfate, have good antiviral, antimetastatic, anti-inflammatory and cell growth inhibitory effects. Due to their broad biological activities and simple structure, sulfated malto-oligomer derivatives have a great therapeutic potential, therefore, the development of efficient synthesis methods for their production is of utmost importance. In this work, preparation of α-(1→4)-linked oligoglucosides containing a sulfonatomethyl moiety at position C-6 of each glucose unit was studied by different approaches. Malto-oligomeric sulfonic acid derivatives up to dodecasaccharides were prepared by polymerization using different protecting groups, and the composition of the product mixtures was analyzed by MALDI-MS methods and size-exclusion chromatography. Synthesis of lower oligomers was also accomplished by stepwise and block synthetic methods, and then the oligosaccharide products were persulfated. The antiviral, anti-inflammatory and cell growth inhibitory activity of the fully sulfated malto-oligosaccharide sulfonic acids were determined by in vitro tests. Four tested di- and trisaccharide sulfonic acids effectively inhibited the activation of the TNF-α-mediated inflammatory pathway without showing cytotoxicity.


Asunto(s)
Oligosacáridos , Sulfatos , Polimerizacion , Oligosacáridos/farmacología , Ácidos Sulfónicos , Antiinflamatorios/farmacología , Antivirales/farmacología
4.
Anal Chem ; 95(28): 10504-10511, 2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37344969

RESUMEN

Gel permeation chromatography (GPC) is a generally applied method for the mass analysis of various polymers and copolymers, but it inherently fails to provide additional important information such as the composition of copolymers. However, we will show that GPC measurements using different solvents can yield not just the correct molecular weight but the composition of the copolymer. Accordingly, artificial neural networks (ANNs) have been developed to process the data of GPC measurements and determine the molecular weight and the chemical composition of the copolymers. The target values of the ANNs were obtained by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and nuclear magnetic resonance (NMR) spectroscopy. Our GPC-ANN method is demonstrated by the analysis of various poloxamers, i.e., poly(ethylene oxide) (PEO)-poly(propylene oxide) (PPO) block copolymers. Two ANNs were constructed. The first one (ANN_1) works in a wider mass range (from 900 to 12,500 dalton), while the second one (ANN_2) produces more output values. ANN_2 can thus predict seven characteristic copolymer parameters, namely, two average molecular weights, the average weight fraction of the EO unit, and four average numbers of the repeat units. The correlation between the experimentally obtained outputs and the predicted ones is high (r > 0.98). The accuracy of the ANNs is very convincing, and both ANNs predict the number-average molecular weight (Mn) with an accuracy below 5%. Furthermore, this work is the first step for creating an open database and applications extending the use of the GPC-ANN method for the analysis of copolymers.

5.
Ann Emerg Med ; 81(4): 468-481, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36117011

RESUMEN

STUDY OBJECTIVE: Many emergency departments (EDs) have identified the importance of HIV prevention and have implemented steps to screen and offer preexposure prophylaxis (PrEP). The objective of this study was to systematically review existing literature that identifies PrEP eligibility in the ED and summarize outcomes along the PrEP cascade of care (awareness, interest, linkage to treatment, initiation, and retention) for patients in ED. METHODS: Four databases captured all PrEP-related studies in EDs from January 1, 2013 to January 27, 2022. Data were extracted on study characteristics and outcomes, and study quality was assessed using a modified quality assessment tool by the Effective Public Health Practice Project. RESULTS: Of the 218 articles, 16 were subjected to full-text review, and 7 met inclusion criteria. Although most studies identified patients who were PrEP eligible using criteria adapted from the 2017 Centers for Disease Control and Prevention PrEP guidelines, the number and time frame for each criterion varied. Six studies reported outcomes on the PrEP cascade of care, showing a relatively high prevalence of awareness and interest but a very low prevalence of linkage and uptake. No studies documented retention in PrEP treatment. CONCLUSION: Although up to a third of patients in ED assessed in the current study were PrEP eligible, less than half of PrEP-eligible participants had prior knowledge of PrEP, and very few who expressed interest in the ED were ultimately linked to PrEP treatment or initiated PrEP. Future research is necessary to identify strategies to increase PrEP education, interest, and linkage to care from the ED.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Profilaxis Pre-Exposición , Humanos , Infecciones por VIH/prevención & control , Fármacos Anti-VIH/uso terapéutico , Servicio de Urgencia en Hospital
6.
Int J Mol Sci ; 24(4)2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36834648

RESUMEN

The main protease (Mpro) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) plays a crucial role in its life cycle. The Mpro-mediated limited proteolysis of the viral polyproteins is necessary for the replication of the virus, and cleavage of the host proteins of the infected cells may also contribute to viral pathogenesis, such as evading the immune responses or triggering cell toxicity. Therefore, the identification of host substrates of the viral protease is of special interest. To identify cleavage sites in cellular substrates of SARS-CoV-2 Mpro, we determined changes in the HEK293T cellular proteome upon expression of the Mpro using two-dimensional gel electrophoresis. The candidate cellular substrates of Mpro were identified by mass spectrometry, and then potential cleavage sites were predicted in silico using NetCorona 1.0 and 3CLP web servers. The existence of the predicted cleavage sites was investigated by in vitro cleavage reactions using recombinant protein substrates containing the candidate target sequences, followed by the determination of cleavage positions using mass spectrometry. Unknown and previously described SARS-CoV-2 Mpro cleavage sites and cellular substrates were also identified. Identification of target sequences is important to understand the specificity of the enzyme, as well as aiding the improvement and development of computational methods for cleavage site prediction.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Células HEK293 , Cisteína Endopeptidasas/metabolismo , Electroforesis , Inhibidores de Proteasas/química , Simulación del Acoplamiento Molecular
7.
Int J Mol Sci ; 24(6)2023 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-36982875

RESUMEN

The oral, highly selective Bcl2 inhibitor venetoclax has substantially improved the therapeutic landscape of chronic lymphocytic leukemia (CLL). Despite the remarkable response rates in patients with relapsed/refractory (R/R) disease, acquired resistance is the leading cause of treatment failure, with somatic BCL2 mutations being the predominant genetic drivers underpinning venetoclax resistance. To assess the correlation between disease progression and the most common BCL2 mutations G101V and D103Y, sensitive (10-4) screening for the most common BCL2 mutations G101V and D103Y was performed in 67 R/R CLL patients during venetoclax single-agent or venetoclax-rituximab combination therapy. With a median follow-up time of 23 months, BCL2 G101V and D103Y were detected in 10.4% (7/67) and 11.9% (8/67) of the cases, respectively, with four patients harboring both resistance mutations. Ten out of eleven patients carrying BCL2 G101V and/or D103Y experienced relapse during the follow-up period, representing 43.5% of the cases (10/23) showing clinical signs of disease progression. All BCL2 G101V or D103Y variants were detected in patients receiving venetoclax as a continuous single-agent treatment while these mutations were not observed during or after fixed-duration venetoclax therapy. Targeted ultra-deep sequencing of BCL2 uncovered three additional variants in four patient samples obtained at relapse, suggesting convergent evolution and implying a cooperating role of BCL2 mutations in driving venetoclax resistance. This cohort is the largest R/R CLL patient population reported to date in which BCL2 resistance mutations were investigated. Our study demonstrates the feasibility and clinical value of sensitive screening for BCL2 resistance mutations in R/R CLL.


Asunto(s)
Antineoplásicos , Leucemia Linfocítica Crónica de Células B , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/genética , Resistencia a Antineoplásicos/genética , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Recurrencia , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Mutación , Proteínas Proto-Oncogénicas c-bcl-2/genética , Progresión de la Enfermedad
8.
Molecules ; 28(9)2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37175198

RESUMEN

Catalytic conversion of ethanol to 1-butanol was studied over MgO-Al2O3 mixed oxide-based catalysts. Relationships between acid-base and catalytic properties and the effect of active metal on the hydrogen transfer reaction steps were investigated. The acid-base properties were studied by temperature-programmed desorption of CO2 and NH3 and by the FT-IR spectroscopic examination of adsorbed pyridine. Dispersion of the metal promoter (Pd, Pt, Ru, Ni) was determined by CO pulse chemisorption. The ethanol coupling reaction was studied using a flow-through microreactor system, He or H2 carrier gas, WHSV = 1 gEtOH·gcat.-1·h-1, at 21 bar, and 200-350 °C. Formation and transformation of surface species under catalytic conditions were studied by DRIFT spectroscopy. The highest butanol selectivity and yield was observed when the MgO-Al2O3 catalyst contained a relatively high amount of strong-base and medium-strong Lewis acid sites. The presence of metal improved the activity both in He and H2; however, the butanol selectivity significantly decreased at temperatures ≥ 300 °C due to acceleration of undesired side reactions. DRIFT spectroscopic results showed that the active metal promoted H-transfer from H2 over the narrow temperature range of 200-250 °C, where the equilibrium allowed significant concentrations of both dehydrogenated and hydrogenated products.

9.
Air Med J ; 42(5): 380-383, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37716813

RESUMEN

Leptospirosis is an infectious illness encountered mostly in tropical climates and has been of particular concern in Haiti after natural disasters. Heavy rainfalls and natural disasters in combination with scarce resources to control and identify clusters of infections make certain populations and countries vulnerable. In some cases, patients who contract this disease may need air medical transport to hospitals that have a higher level of care. In this case report, a trio of cases is highlighted from an outbreak that required air transport to transfer patients to a facility with the availability of an intensive care unit. The goal of highlighting these cases is to increase the awareness of physicians and air transport providers to the manifestation and treatment of this disease and to provide pearls to stabilize patients during transport.


Asunto(s)
Ambulancias Aéreas , Leptospirosis , Humanos , Brotes de Enfermedades , Haití/epidemiología , Leptospirosis/diagnóstico , Leptospirosis/epidemiología , Leptospirosis/terapia
10.
Int J Mol Sci ; 23(13)2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35806254

RESUMEN

Fluorescent probes that exhibit solvatochromic or excited-state proton-transfer (ESPT) properties are essential tools for the study of complex biological or chemical systems. Herein, the synthesis and characterization of a novel fluorophore that reveals both features, 5-isocyanonaphthalene-1-ol (ICOL), are reported. Various solvatochromic methods, such as Lippert−Mataga and Bilot−Kawski, together with time-dependent density functional theory (TD-DFT) and time-resolved emission spectroscopy (TRES), were applied to gain insights into its excited-state behavior. To make comparisons, the octyloxy derivative of ICOL, 5-isocyano-1-(octyloxy)naphthalene (ICON), was also prepared. We found that internal charge transfer (ICT) takes place between the isocyano and −OH groups of ICOL, and we determined the values of the dipole moments for the ground and excited states of both ICOL and ICON. Furthermore, in the emission spectra of ICOL, a second band at higher wavelengths (green emission) in solvents of higher polarities (dual emission), in addition to the band present at lower wavelengths (blue emission), were observed. The extent of this dual emission increases in the order of 2-propanol < methanol < N,N-dimethylformamide (DMF) < dimethyl sulfoxide (DMSO). The presence of the dual fluorescence of ICOL in these solvents can be ascribed to ESPT. For ICOL, we also determined ground- and excited-state pKa values of 8.4 ± 0.3 and 0.9 ± 0.7, respectively, which indicates a considerable increase in acidity upon excitation. The TRES experiments showed that the excited-state lifetimes of the ICOL and ICON spanned from 10.1 ns to 5.0 ns and from 5.7 ns to 3.8 ns, respectively. In addition, we demonstrated that ICOL can be used as an effective indicator of not only the critical micelle concentration (cmc) of ionic (sodium lauryl sulfate (SLS)) and nonionic surfactants (Tween 80), but also other micellar parameters, such as partition coefficients, as well as to map the microenvironments in the cavities of biomacromolecules (e.g., BSA). It is also pointed out that fluorescence quenching by pyridine can effectively be utilized for the determination of the fractions of ICOL molecules that reside at the water−micelle interface and in the interior spaces of micelles.


Asunto(s)
Micelas , Protones , Colorantes Fluorescentes , Metanol , Solventes/química , Espectrometría de Fluorescencia
11.
Int J Mol Sci ; 23(21)2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-36361862

RESUMEN

Duchenne muscular dystrophy (DMD) is the most common inherited muscle dystrophy. Patients are characterized by muscle weakness, gross motor delay, and elevated serum creatinine kinase (CK) levels. The disease is caused by mutations in the DMD gene located on the X chromosome. Due to the X-linked recessive inheritance pattern, DMD most commonly affects males, who are generally diagnosed between the age of 3-5 years. Here we present an ultra-rare manifestation of DMD in a female patient. Cytogenetic examination showed that she has a t(X;10)(p21.1;p12.1) translocation, which turned out to affect the DMD gene with one of the breakpoints located in exon 54 (detected by genome sequencing). The X-inactivation test revealed skewed X-inactivation (ratio 99:1). Muscle histology and dystrophin immunohistochemistry showed severe dystrophic changes and highly reduced dystrophin expression, respectively. These results, in accordance with the clinical picture and a highly elevated serum CK, led to the diagnosis of DMD. In conclusion, although in very rare cases, DMD can manifest in female patients as well. In this case, a balanced X-autosome reciprocal translocation disrupts the DMD gene and skewed X-inactivation leads to the manifestation of the DMD phenotype.


Asunto(s)
Distrofina , Distrofia Muscular de Duchenne , Masculino , Femenino , Humanos , Distrofina/genética , Distrofia Muscular de Duchenne/diagnóstico , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/patología , Inactivación del Cromosoma X , Cromosoma X , Mutación
12.
Br J Haematol ; 194(2): 355-364, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34019713

RESUMEN

The Bruton's tyrosine kinase (BTK) inhibitor ibrutinib has revolutionised the therapeutic landscape of chronic lymphocytic leukaemia (CLL). Acquired mutations emerging at position C481 in the BTK tyrosine kinase domain are the predominant genetic alterations associated with secondary ibrutinib resistance. To assess the correlation between disease progression, and the emergence and temporal dynamics of the most common resistance mutation BTKC481S , sensitive (10-4 ) time-resolved screening was performed in 83 relapsed/refractory CLL patients during single-agent ibrutinib treatment. With a median follow-up time of 40 months, BTKC481S was detected in 48·2% (40/83) of the patients, with 80·0% (32/40) of them showing disease progression during the examined period. In these 32 cases, representing 72·7% (32/44) of all patients experiencing relapse, emergence of the BTKC481S mutation preceded the symptoms of clinical relapse with a median of nine months. Subsequent Bcl-2 inhibition therapy applied in 28/32 patients harbouring BTKC481S and progressing on ibrutinib conferred clinical and molecular remission across the patients. Our study demonstrates the clinical value of sensitive BTKC481S monitoring with the largest longitudinally analysed real-world patient cohort reported to date and validates the feasibility of an early prediction of relapse in the majority of ibrutinib-treated relapsed/refractory CLL patients experiencing disease progression.


Asunto(s)
Adenina/análogos & derivados , Agammaglobulinemia Tirosina Quinasa/genética , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Piperidinas/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico , Adenina/uso terapéutico , Adulto , Agammaglobulinemia Tirosina Quinasa/antagonistas & inhibidores , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Leucemia Linfocítica Crónica de Células B/diagnóstico , Leucemia Linfocítica Crónica de Células B/genética , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/genética , Mutación Puntual/efectos de los fármacos
13.
Int J Mol Sci ; 22(2)2021 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-33467107

RESUMEN

Flavonoids represent an important class of secondary metabolites because of their potential health benefits and functions in plants. We propose a novel method for the comprehensive flavonoid filtering and screening based on direct infusion mass spectrometry (DIMS) analysis. The recently invented data mining procedure, the multi-step mass-remainder analysis (M-MARA) technique is applied for the effective mass spectral filtering of the peak rich spectra of natural herb extracts. In addition, our flavonoid-filtering algorithm facilitates the determination of the elemental composition. M-MARA flavonoid-filtering uses simple mathematical and logical operations and thus, it can easily be implemented in a regular spreadsheet software. A huge benefit of our method is the high speed and the low demand for computing power and memory that enables the real time application even for tandem mass spectrometric analysis. Our novel method was applied for the electrospray ionization (ESI) DIMS spectra of various herb extract, and the filtered mass spectral data were subjected to chemometrics analysis using principal component analysis (PCA).


Asunto(s)
Flavonoides/química , Metabolómica/métodos , Extractos Vegetales/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Flavonoides/análisis , Metabolómica/normas , Análisis de Componente Principal , Espectrometría de Masas en Tándem/normas
14.
Int J Mol Sci ; 22(21)2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34769008

RESUMEN

Basic leucine zipper (bZIP) transcription factors play a crucial role in the environmental stress response of eukaryotes. In this work, we studied the effect of gene manipulations, including both deletions and overexpressions, of two selected bZIP transcription factors, NapA and RsmA, in the oxidative stress response and sterigmatocystin production of Aspergillus nidulans. We found that NapA was important in the oxidative stress response by negatively regulating intracellular reactive species production and positively regulating catalase activities, whereas RsmA slightly negatively regulated catalase activities. Concerning sterigmatocystin production, the highest concentration was measured in the ΔrsmAΔnapA double deletion mutant, but elevated sterigmatocystin production was also found in the OErsmA OEnapA strain. Our results indicate that NapA influences sterigmatocystin production via regulating reactive species level whereas RsmA modulates toxin production independently of the redox regulation of the cells.


Asunto(s)
Aspergillus nidulans/genética , Aspergillus nidulans/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Proteínas Fúngicas/genética , Especies Reactivas de Oxígeno/metabolismo , Esterigmatocistina/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica/genética , Oxidación-Reducción , Estrés Oxidativo/genética , Estrés Fisiológico/genética
15.
Int J Mol Sci ; 22(4)2021 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-33562082

RESUMEN

The use of peptide-drug conjugates has generated wide interest as targeted antitumor therapeutics. The anthracycline antibiotic, daunomycin, is a widely used anticancer agent and it is often conjugated to different tumor homing peptides. However, comprehensive analytical characterization of these conjugates via tandem mass spectrometry (MS/MS) is challenging due to the lability of the O-glycosidic bond and the appearance of MS/MS fragment ions with little structural information. Therefore, we aimed to investigate the optimal fragmentation conditions that suppress the prevalent dissociation of the anthracycline drug and provide good sequence coverage. In this study, we comprehensively compared the performance of common fragmentation techniques, such as higher energy collisional dissociation (HCD), electron transfer dissociation (ETD), electron-transfer higher energy collisional dissociation (EThcD) and matrix-assisted laser desorption/ionization-tandem time-of-flight (MALDI-TOF/TOF) activation methods for the structural identification of synthetic daunomycin-peptide conjugates by high-resolution tandem mass spectrometry. Our results showed that peptide backbone fragmentation was inhibited by applying electron-based dissociation methods to conjugates, most possibly due to the "electron predator" effect of the daunomycin. We found that efficient HCD fragmentation was largely influenced by several factors, such as amino acid sequences, charge states and HCD energy. High energy HCD and MALDI-TOF/TOF combined with collision induced dissociation (CID) mode are the methods of choice to unambiguously assign the sequence, localize different conjugation sites and differentiate conjugate isomers.


Asunto(s)
Daunorrubicina/análogos & derivados , Daunorrubicina/metabolismo , Péptidos/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Espectrometría de Masas en Tándem/métodos , Secuencia de Aminoácidos , Daunorrubicina/química , Transporte de Electrón , Péptidos/química , Conformación Proteica
16.
Int J Mol Sci ; 21(24)2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33333742

RESUMEN

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease-19 (COVID-19) being associated with severe pneumonia. Like with other viruses, the interaction of SARS-CoV-2 with host cell proteins is necessary for successful replication, and cleavage of cellular targets by the viral protease also may contribute to the pathogenesis, but knowledge about the human proteins that are processed by the main protease (3CLpro) of SARS-CoV-2 is still limited. We tested the prediction potentials of two different in silico methods for the identification of SARS-CoV-2 3CLpro cleavage sites in human proteins. Short stretches of homologous host-pathogen protein sequences (SSHHPS) that are present in SARS-CoV-2 polyprotein and human proteins were identified using BLAST analysis, and the NetCorona 1.0 webserver was used to successfully predict cleavage sites, although this method was primarily developed for SARS-CoV. Human C-terminal-binding protein 1 (CTBP1) was found to be cleaved in vitro by SARS-CoV-2 3CLpro, the existence of the cleavage site was proved experimentally by using a His6-MBP-mEYFP recombinant substrate containing the predicted target sequence. Our results highlight both potentials and limitations of the tested algorithms. The identification of candidate host substrates of 3CLpro may help better develop an understanding of the molecular mechanisms behind the replication and pathogenesis of SARS-CoV-2.


Asunto(s)
COVID-19/virología , Proteasas 3C de Coronavirus/metabolismo , SARS-CoV-2/enzimología , Oxidorreductasas de Alcohol/metabolismo , Secuencia de Aminoácidos , Proteasas 3C de Coronavirus/química , Proteasas 3C de Coronavirus/genética , Proteínas de Unión al ADN/metabolismo , Interacciones Huésped-Patógeno , Humanos , SARS-CoV-2/genética , Especificidad por Sustrato
17.
Int J Mol Sci ; 21(4)2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-32075293

RESUMEN

In this article, the capability of encoding information using a homologous series of monodisperse monomethoxypolyethylene glycols (mPEG), with a number of ethylene oxide units ranging from nEO = 5 to 8, and monodisperse linear aliphatic isocyanates containing a number of CH2 units from 3 to 7, is demonstrated. The "click" reaction of the two corresponding homologous series yielded 20 different isocyanate end-capped polyethylene glycol derivatives (mPEG-OCONHR) whose sodiated adduct ion's nominal m/z values spanned from 360 to 548, providing an average ca. 8 m/z unit for the storage of one-bit information. These mPEG-OCONHR oligomers were then used to encode information in binary sequences using a 384-well MALDI sample plate and employing the common dried-droplet sample preparation method capable of encoding 20 bit, i.e., 2.5 byte information in one spot, was employed. The information stored in the spots was read by MALDI-TOF MS using the m/z value of the corresponding mPEG-OCONHR oligomers. The capability of the method to store data was demonstrated by writing and reading a text file, visualizing a small picture and capturing a short audio file written in Musical Instrument Digital Interface (MIDI) sequence. Due to the very large similarities in the chemical structures of the encoding oligomers and their "easy to be ionized" property, as well as their very similar ionization efficiencies, the MALDI-TOF MS signal intensities from each compound was so strong and unambiguous that complete decoding could be performed in each case. In addition, the set of the proposed encoding oligomers can be further extended to attain higher bit "densities".


Asunto(s)
Química Clic , Almacenamiento y Recuperación de la Información , Isocianatos/química , Polietilenglicoles/química , Etanol/química , Humanos , Iones/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
18.
Int J Mol Sci ; 21(2)2020 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-31968535

RESUMEN

Photodynamic therapy is a non-invasive method where light activates a photosensitizer bound to cancer cells, generating reactive oxygen species and resulting in cell death. This study assessed the oncolytic potential of photodynamic therapy, comparing European Medicines Agency and United States Food and Drug Administration-approved 5-aminolevulinic acid (5-ALA) to a metalloporphyrin, Pd(T4), against a highly invasive uveal melanoma cell line (C918) in two- and three-dimensional models in vitro. Epithelial monolayer studies displayed strong oncolytic effects (>70%) when utilizing Pd(T4) at a fraction of the concentration, and reduced pre-illumination time compared to 5-ALA post-405 nm irradiance. When analyzed at sub-optimal concentrations, application of Pd(T4) and 5-ALA with 405 nm displayed cumulative effects. Lethality from Pd(T4)-photodynamic therapy was maintained within a three-dimensional model, including the more resilient vasculogenic mimicry-forming cells, though at lower rates. At high concentrations, modality of cell death exhibited necrosis partially dependent on reactive oxygen species. However, sub-optimal concentrations of photosensitizer exhibited an apoptotic protein expression profile characterized by increased Bax/Bcl-2 ratio and endoplasmic stress-related proteins, along with downregulation of apoptotic inhibitors CIAP-1 and -2. Together, our results indicate Pd(T4) as a strong photosensitizer alone and in combination with 5-ALA against C918 cells.


Asunto(s)
Ácido Aminolevulínico/farmacología , Antineoplásicos/farmacología , Melanoma/tratamiento farmacológico , Metaloporfirinas/farmacología , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Neoplasias de la Úvea/tratamiento farmacológico , Ácido Aminolevulínico/química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Luz , Metaloporfirinas/química , Necrosis/tratamiento farmacológico , Fármacos Fotosensibilizantes/química , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteína X Asociada a bcl-2/metabolismo
19.
Yale J Biol Med ; 93(2): 291-305, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32607090

RESUMEN

Essential oils (EOs) have risen in popularity over the past decade. These oils function in society as holistic integrative modalities to traditional medicinal treatments, where many Americans substitute EOs in place of other prescribed medications. EOs are found in a multitude of products including food flavoring, soaps, lotions, shampoos, hair styling products, cologne, laundry detergents, and even insect repellents. EOs are complex substances comprised of hundreds of components that can vary greatly in their composition depending upon the extraction process by the producer or the origin of the plant. Thus, making it difficult to determine which pathways in the body are affected. Here, we review the published research that shows the health benefits of EOs as well as some of their adverse effects. In doing so, we show that EOs, as well as some of their individual components, possess antimicrobial, antiviral, antibiotic, anti-inflammatory, and antioxidant properties as well as purported psychogenic effects such as relieving stress, treating depression, and aiding with insomnia. Not only do we show the health benefits of using EOs, but we also indicate risks associated with their use such as their endocrine disrupting properties leading to the induction of premature breast growth in young adolescents. Taken together, there are many positive and potentially negative risks to human health associated with EOs, which make it important to bring awareness to all their known effects on the human body.


Asunto(s)
Aromaterapia/métodos , Aceites Volátiles , Humanos , Medicina Tradicional/métodos , Aceites Volátiles/efectos adversos , Aceites Volátiles/farmacología , Medición de Riesgo
20.
Anal Chem ; 91(10): 6479-6486, 2019 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-30912635

RESUMEN

Data processing and visualization methods have an important role in the mass spectrometric study of crude oils and other natural samples. The recently invented data mining procedure, Mass-Remainder Analysis (MARA), was further developed for use in petroleomics. MARA is based on the calculation of the remainder after dividing by the exact mass of a base unit, in petroleomics by the mass of the CH2 group. The two key steps in the MARA algorithm are the separation of the monoisotopic peaks from the other isotopic peaks and the subsequent intensity correction. The effectiveness of our MARA method was demonstrated on the analysis of lubricating mineral oil and crude oil samples by ultra-high-resolution Fourier transform ion cyclotron resonance mass spectrometry experiments. MARA is able to handle a huge portion of the overlapped peaks even in a moderate resolution mass spectrum. With use of MARA, effective chemical composition assignment and visual representation were achieved for complex mass spectra recorded by a time-of-flight analyzer with a limited resolution of 40 000 at m/ z 400. In the absence of an ultra-high-resolution mass analyzer, MARA can provide a closer look on the mass spectral peaks, like a digital zoom in a simple camera.


Asunto(s)
Petróleo/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos
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