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1.
COPD ; 19(1): 309-314, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35829649

RESUMEN

Patients with chronic obstructive pulmonary disease (COPD) may have a limited level of physical activity in daily life (PADL) and health-related quality of life (HRQOL). The interrelationships of these variables should be measure by cluster analysis to characterize this population and enable rehabilitation programs to target each patient profile identified. This study investigates different phenotypes in COPD according to PADL and HRQOL. A cross-sectional study with cluster analysis was done, in which 76 people with COPD were submitted to measurements to characterize the sample on first day, followed by used of physical activity monitor, which was worn for 7 days. After 7 days, the six-minute walk test (6MWT) and HRQOL questionnaires were applied (St. George's Respiratory Questionnaire). The main results: three phenotypes were identified (A, B and C), with phenotype A who exhibited an inactive physical activity level and HRQOL scores above the value deemed satisfactory, phenotype B those with active physical activity level and poor HRQOL scores, and phenotype C subjects with inactive physical activity level and HRQOL scores but the value is close to cutoff point. To conclude, three phenotypes were found, with one indicating disproportionality between PADL and HRQOL.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica , Análisis por Conglomerados , Estudios Transversales , Ejercicio Físico , Humanos , Calidad de Vida , Encuestas y Cuestionarios
2.
J Org Chem ; 85(11): 7333-7341, 2020 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-32397710

RESUMEN

Light-activated sensors are of great interest for biological applications but are limited by the depth of penetration of light. We have been interested in transducing light activation to a magnetic signal that can be detected through noninvasive imaging by magnetic resonance imaging (MRI). We have previously developed agents incorporating spiropyran derivatives as the sensing moiety and characterized features that influence photoswitching; however, we found the MRI response to be unpredictable. In this work, we delve deeper into the potential mechanisms for the observed MRI responses in an effort to better understand the structural effects on controlling magnetic properties. A series of light-activatable MRI contrast agents were synthesized and characterized to assess the effect of spiropyran positioning on contrast agent functions and properties. These compounds are based on the same spiropyran skeleton, also named 1',3',3'-trimethyl-6-nitrospiro[chromene-2,2-indoline], which is linked with an MRI contrast agent, gadolinium-1,4,7,10-tetraazacyclododecane-1,4,7-triacetate (DO3A). We investigated the photo-to-magnetic conversion properties of these novel compounds by adjusting linker lengths over a range from three to seven methylene groups. The primary results indicated that the contrast agent with a five-carbon linker (25) showed the highest light-sensing ability after irradiation with visible light. The results will aid in the design of future spiropyran-based MRI sensors.


Asunto(s)
Medios de Contraste , Gadolinio , Imagen por Resonancia Magnética
3.
Phys Chem Chem Phys ; 21(30): 16515-16525, 2019 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-31298238

RESUMEN

Isoniazid (INH) is converted into isonicotinyl radical through its interaction with the catalase-peroxidase (katG) enzyme present in the cells of Mycobacterium tuberculosis (M. tb.), the bacteria that causes the tuberculosis disease. This process is important because resistance of M. tb. cells to INH treatment has been associated with the failure of completion of this process. However, this process is poorly understood and there are a variety of conflicting theories about the details of the mechanism of this process. One theory suggests that INH binds to katG and transfers a single electron to the heme while the heme is in its two electron oxidized state, compound I [Fe(iv)Por˙+] (CpdI). In this study, DFT calculations at the UB3LYP/6-31g(d)-LANL2DZ level of theory are used to study the M. tb. katG CpdI molecule. Different models of the M. tb. CpdI molecule were prepared and the calculations revealed the impact of Trp321 on the electronic properties of the heme. Without Trp321 the heme assumed a triradical state with single electrons on the πxy and πyz orbitals of Fe and another on the a2u orbital of the porphyrin ring that can either be coupled with the first two, to assume a quartet state, or decoupled to form a doublet state. With Trp321, however, a transfer of an electron from the πTrp orbital to a2u porphyrin orbital leads to loss of radical character of the porphyrin and leaves the Trp321 group with a radical character. INH was observed to have strong interaction with CpdI and the absence of Trp321 significantly decreased the binding energy by 2 kcal mol-1 explaining the importance of Trp321 in the binding of INH. The results in this study show the importance of Trp321 in the binding of INH and its effect on its electronic properties, which is consistent with previous experimental findings that mutation of Trp321 results in an increase in drug resistance.


Asunto(s)
Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Catalasa/química , Catalasa/metabolismo , Teoría Funcional de la Densidad , Isoniazida/metabolismo , Antituberculosos/metabolismo
4.
An Acad Bras Cienc ; 91(3): e20181104, 2019 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-31432905

RESUMEN

We recorded a second specimen of the poorly known insular blind snake Liotyphlops caissara. This new specimen expands the morphological variation of the number of dorsal scales in the genus Liotyphlops to 296 (vs. 304 in L. wilderi) and, considering the fact that the holotype of this species was destroyed, the present specimen represents the only available L. caissara individual in zoological collections. Also, this new record constitutes the first out of type locality and expands the distribution of the species in about 40 km to the northeastern. According to IUCN criteria (B1a, b [iii]), we suggest that L. caissara be included in the "Endangered" category, since it occurs in only two insular locations and exhibits an occurrence extension of <5,000 km² (about 355 km2).


Asunto(s)
Serpientes/clasificación , Distribución Animal , Animales , Brasil , Masculino , Serpientes/anatomía & histología
5.
Int J Cancer ; 138(7): 1670-9, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-26537841

RESUMEN

The colonic opportunist Streptococcus gallolyticus subspecies gallolyticus (SGG) is potentially associated with colorectal cancer (CRC). Large-scale seroepidemiological data for SGG antibodies and their possible association with CRC is currently missing. Associations between CRC and antibody responses to SGG were examined in 576 CRC cases and 576 controls matched by sex, age and province from a population-based multicase-control project (MCC-Spain). MCC-Spain was conducted between 2008 and 2013 in 12 Spanish provinces. Antibody responses to recombinant affinity-purified SGG pilus proteins Gallo1569, 2039, 2178 and 2179 were analysed by multiplex serology. Polyomavirus (PyV) JC VP1 and PyV 6 VP1 proteins served as disease-specificity controls. In the control population, antibody responses to pilus proteins were mostly weak. Antibody responses to individual pilus proteins Gallo2039 (OR: 1.58, 95% CI: 1.09-2.28), Gallo2178 (OR: 1.58, 95% CI: 1.09-2.30) and Gallo2179 (OR: 1.45, 95% CI: 1.00-2.11) were significantly associated with CRC risk. The association was stronger for positivity to two or more pilus proteins of Gallo1569, Gallo2178 and Gallo2179 (OR:1.93, 95% CI: 1.04-3.56) and for double-positivity to Gallo2178 and Gallo2179 (OR: 3.54, 95% CI: 1.49-8.44). The association between SGG infection and CRC risk was stronger among individuals younger than 65 years. For the first time we demonstrated a statistically significant association of exposure to SGG antigens and CRC in a large seroepidemiological study. These results should stimulate further studies on the role of SGG in CRC pathogenesis.


Asunto(s)
Neoplasias Colorrectales/microbiología , Infecciones Estreptocócicas/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/sangre , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Seroepidemiológicos , España/epidemiología , Streptococcus , Adulto Joven
6.
Bioorg Med Chem ; 23(10): 2328-43, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25882520

RESUMEN

Hepatocyte growth factor activator (HGFA), matriptase and hepsin are all S1 trypsin-like serine endopeptidases. HGFA is a plasma protease while hepsin and matriptase are type II transmembrane proteases (TTSPs). Upregulated expression and activity of all three proteases is associated with aberrant cancer cell signaling through c-MET and RON tyrosine kinase cell-signaling pathways in cancer. We modeled known benzamidine protease inhibitor scaffolds into the active sites of matriptase, hepsin and HGFA to design new non-peptide inhibitors of hepsin and HGFA. First, we used a docking model of the irreversible inhibitor, Nafamostat, bound to the active site of HGFA in order to explore structure activity relationships (SAR). Compounds were screened for inhibition of HGFA activity in a kinetic enzyme assay using a chromogenic substrate. Next, we designed matched pair compound libraries of 3-amidino and 4-amidino phenylalanine (benzamidine) arginine peptidomimetics based on the structure of matriptase inhibitor, CJ-672. Compounds were screened for inhibition of HGFA, matriptase, and hepsin enzyme activity using fluorogenic substrates. Using this strategy we have discovered the first reported non-peptide small molecule inhibitors of both HGFA and hepsin. These inhibitors have differential potency and selectivity towards all three proteases. A subset of piperazinyl ureas highlighted by 25a, have excellent potency and selectivity for hepsin over matriptase and HGFA.


Asunto(s)
Antineoplásicos/síntesis química , Benzamidinas/síntesis química , Proteínas de Neoplasias/antagonistas & inhibidores , Inhibidores de Proteasas/síntesis química , Serina Endopeptidasas/química , Amidinas/síntesis química , Antineoplásicos/farmacología , Arginina/química , Benzamidinas/farmacología , Dominio Catalítico , Diseño de Fármacos , Pruebas de Enzimas , Guanidinas/química , Ensayos Analíticos de Alto Rendimiento , Humanos , Cinética , Simulación del Acoplamiento Molecular , Proteínas de Neoplasias/química , Peptidomiméticos/química , Fenilalanina/análogos & derivados , Fenilalanina/síntesis química , Piperazinas/síntesis química , Inhibidores de Proteasas/farmacología , Proteínas Recombinantes/química , Relación Estructura-Actividad , Urea/análogos & derivados , Urea/química
7.
Cardiooncology ; 10(1): 1, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38167231

RESUMEN

BACKGROUND: CT- coronary calcium score, is one of the most studied and widely available modalities in cardiovascular medicine. Coronary artery calcium score (CACS) is an established predictor of coronary artery disease. The 'standard of care' diagnostic modality to measure CACS is ECG-gated Cardiac Multi-Detector Computed Tomography. There is convincing evidence of a strong association between CACS and major cardiovascular (CV) events in asymptomatic individuals. Cancer patients (C) may have a higher risk for CV disease than non-cancer patients (NC) related not only to cancer treatments but also to shared biological factors and pathways. Thus, identifying tools for early detection of CV disease in this population is of utmost importance. METHODS: A retrospective cohort analysis was performed with patients from Cleveland Clinic Florida and Ohio who had CACS from 2017 to 2021. Patients who had cancer diagnosis prior to CACS were matched to NC for age and sex. CV events after their index CACS events were compared between C and NC, and matched control and propensity analysis were conducted. RESULTS: Ten thousand seven hundred forty-two patients had CACS; 703 cancer patients had CACS and were eligible. Extensive CACS (> 400) were significantly higher in cancer, 94 (13.37%) vs non-cancer patients, 76 (10.83%), P = 0.011. Furthermore, after propensity matched analysis, CACS > 400 was 14.8% in C vs 9.6% in NC, P = < 0.05. CV events were similar in both cohorts (p = NS), despite less CV risk factors in cancer patients (P = < 0.05). For the combined moderate (101-400) & extensive (> 400) CACS, the prevalence of stroke and peripheral arterial disease, a marker of systemic atherosclerosis, was significantly higher in patients with cancer (P < 0.01). CONCLUSIONS: Despite having fewer CV risk factors in our study, similar CACS in cancer patients are suggestive of a higher prevalence of CV disease independent of traditional risk factors. High CACS and the overall prevalence of vascular events were more frequent in patients with cancer. Higher prevalence of peripheral arterial disease and cerebrovascular accident further suggests the increased atherosclerotic burden in C.

8.
ChemMedChem ; 19(8): e202300648, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38300970

RESUMEN

The DNA excision repair protein ERCC1 and the DNA damage sensor protein, XPA are highly overexpressed in patient samples of cisplatin-resistant solid tumors including lung, bladder, ovarian, and testicular cancer. The repair of cisplatin-DNA crosslinks is dependent upon nucleotide excision repair (NER) that is modulated by protein-protein binding interactions of ERCC1, the endonuclease, XPF, and XPA. Thus, inhibition of their function is a potential therapeutic strategy for the selective sensitization of tumors to DNA-damaging platinum-based cancer therapy. Here, we report on new small-molecule antagonists of the ERCC1/XPA protein-protein interaction (PPI) discovered using a high-throughput competitive fluorescence polarization binding assay. We discovered a unique structural class of thiopyridine-3-carbonitrile PPI antagonists that block a truncated XPA polypeptide from binding to ERCC1. Preliminary hit-to-lead studies from compound 1 reveal structure-activity relationships (SAR) and identify lead compound 27 o with an EC50 of 4.7 µM. Furthermore, chemical shift perturbation mapping by NMR confirms that 1 binds within the same site as the truncated XPA67-80 peptide. These novel ERCC1 antagonists are useful chemical biology tools for investigating DNA damage repair pathways and provide a good starting point for medicinal chemistry optimization as therapeutics for sensitizing tumors to DNA damaging agents and overcoming resistance to platinum-based chemotherapy.


Asunto(s)
Cisplatino , Neoplasias Testiculares , Humanos , Masculino , Cisplatino/farmacología , ADN/metabolismo , Daño del ADN , Reparación del ADN , Proteínas de Unión al ADN/química , Endonucleasas/metabolismo , Péptidos/metabolismo , Proteína de la Xerodermia Pigmentosa del Grupo A/química , Proteína de la Xerodermia Pigmentosa del Grupo A/genética , Proteína de la Xerodermia Pigmentosa del Grupo A/metabolismo , Femenino
9.
Environ Sci Pollut Res Int ; 31(25): 37298-37315, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38769263

RESUMEN

Five phyllosilicates (kaolinite, montmorillonite, saponite, sepiolite and palygorskite) have been selected as starting materials for the synthesis of zeolites. Among them, kaolinite and montmorillonite display the lowest Si/Al molar ratio leading to aluminosilicates with high crystallinity. Thus, the hydrothermal treatment under basic conditions forms 4A zeolite when kaolinite is used as starting material while 13X zeolite is obtained when montmorillonite is used as starting material. The microporosity and CO2-adsorption capacity of the prepared zeolites are directly related to its crystallinity. Thus, in order to improve it, raw phyllosilicates were subjected to a microwave-assisted treatment to remove undesired Mg or Fe-species, which have a negative effect in the assembling of the zeolites by hydrothermal basic conditions in a second step. The highest adsorption value was 3.85 mmol/g at 25 °C and 760 mm of Hg for Mont-A-B sample after the consecutive treatments.


Asunto(s)
Dióxido de Carbono , Zeolitas , Zeolitas/química , Adsorción , Dióxido de Carbono/química , Silicatos/química , Bentonita/química
10.
Bioorg Med Chem Lett ; 23(4): 1120-6, 2013 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-23298810

RESUMEN

Microsomal prostaglandin E(2) synthase-1 (mPGES-1) is a novel therapeutic target for the treatment of inflammation and pain. In the preceding letter, we detailed the discovery of clinical candidate PF-04693627, a potent mPGES-1 inhibitor possessing a novel benzoxazole structure. While PF-04693627 was undergoing further preclinical profiling, we sought to identify a back-up mPGES-1 inhibitor that differentiated itself from PF-04693627. The design, synthesis, mPGES-1 activity and in vivo PK of a novel set of substituted benzoxazoles are described herein. Also described is a conformation-based hypothesis for mPGES-1 activity based on the preferred conformation of the cyclohexane ring within this class of inhibitors.


Asunto(s)
Benzoxazoles/química , Benzoxazoles/farmacología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Oxidorreductasas Intramoleculares/antagonistas & inhibidores , Benzoxazoles/síntesis química , Diseño de Fármacos , Inhibidores Enzimáticos/síntesis química , Humanos , Oxidorreductasas Intramoleculares/química , Oxidorreductasas Intramoleculares/metabolismo , Modelos Moleculares , Conformación Molecular , Prostaglandina-E Sintasas , Relación Estructura-Actividad
11.
An Acad Bras Cienc ; 90(2): 1279-1284, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29898095
12.
J Telemed Telecare ; : 1357633X231188394, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37559399

RESUMEN

INTRODUCTION: Individuals with severe coronavirus disease 2019 (COVID-19) may present respiratory and motor complications, requiring rehabilitation programs (RP) for long periods. However, access to cardiopulmonary rehabilitation is poor. Cardiopulmonary telerehabilitation is an alternative for cardiopulmonary dysfunction, improving functional capacity, dyspnea, and quality of life. Moreover, few clinical trials verified the effectiveness of telerehabilitation using functional exercise for post-COVID symptoms. Thus, the present study aimed to verify the effects of cardiopulmonary telerehabilitation using functional and accessible exercises in individuals after COVID-19 hospital discharge. METHODS: This blinded, randomized, and controlled clinical trial and included 67 adult individuals after COVID-19 hospital discharge. Participants were randomized into the groups of telerehabilitation (TG; n = 33) and control (CG; n = 34). TG underwent an individualized exercise program (functional and accessible exercises) supervised by a physical therapist (videoconference), and CG received guidance on general care and self-monitoring of vital signs (videoconference). The primary outcome was performance and physiological responses on the 6-minute step test (6MST). Secondary outcomes were performance on the 2-minute stationary walk test (2MSWT), 30-second chair stand test (30CST), and quality of life using the 36-Item Short Form Health Survey (SF-36) questionnaire physical functioning concept (PF). RESULTS: Functional capacity (6MST) improved by 28 ± 17 steps in TG and 15 ± 26 in CG (p = 0.04). For secondary outcomes, performance on 2MSWT increased by 39 ± 6 steps in TG and 10 ± 6 in CG (p = 0.00); 30CST by 3 ± 1 repetitions in TG and 1.5 ± 0.5 in CG (p = 0.05); and PF (SF-36) by 17 ± 4 points in TG and 12 ± 4 in CG (p = 0.00). Also, peak oxygen uptake VO2peak (6MST) improved by 3.8 ± 1 mL min-1 kg-1 in TG and 4.1 ± 1 in CG (p = 0.6), and heart rate demand (6MST) by 11 ± 37% in TG and -4 ± 19% in CG (p = 0.04). CONCLUSIONS: Cardiopulmonary telerehabilitation using functional exercises improved the exercise and functional capacity assessed using 6MST, 30CST, and 2MSWT and the quality of life of individuals after COVID-19 hospital discharge.

13.
Z Naturforsch C J Biosci ; 66(5-6): 235-44, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21812340

RESUMEN

Cycloartenyl stearate (1a), lupenyl stearate (1b), sitosteryl stearate (1c), and 24-methylenecycloartanyl stearate (1d) (sample 1) from the air-dried leaves of Syzygium samarangense exhibited potent analgesic and anti-inflammatory activities at effective doses of 6.25 mg/kg body weight and 12.5 mg/kg body weight, respectively. Sample 1 also exhibited negligible toxicity on zebrafish embryonic tissues. There were incidences of mortality upon direct exposure of sample 1 to dechorionated embryos, but higher mortality and aberration were observed during intact chorion treatment.


Asunto(s)
Esteroles/farmacología , Syzygium/química , Triterpenos/farmacología , Pez Cebra/embriología , Analgésicos/farmacología , Animales , Antiinflamatorios/farmacología , Espectroscopía de Resonancia Magnética , Ratones , Ratones Endogámicos ICR , Esteroles/aislamiento & purificación , Triterpenos/aislamiento & purificación
14.
Iran J Basic Med Sci ; 24(6): 699-719, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34630947

RESUMEN

A perilous increase in the number of bacterial infections has led to developing throngs of antibiotics for increasing the quality and expectancy of life. Pseudomonas aeruginosa is becoming resistant to all known conventional antimicrobial agents thereby posing a deadly threat to the human population. Nowadays, targeting virulence traits of infectious agents is an alternative approach to antimicrobials that is gaining much popularity to fight antimicrobial resistance. Quorum sensing (QS) involves interspecies communication via a chemical signaling pathway. Under this mechanism, cells work in a concerted manner, communicate with each other with the help of signaling molecules called auto-inducers (AI). The virulence of these strains is driven by genes, whose expression is regulated by AI, which in turn acts as transcriptional activators. Moreover, the problem of antibiotic-resistance in case of infections caused by P. aeruginosa becomes more alarming among immune-compromised patients, where the infectious agents easily take over the cellular machinery of the host while hidden in the QS mediated biofilms. Inhibition of the QS circuit of P. aeruginosa by targeting various signaling pathways such as LasR, RhlR, Pqs, and QScR transcriptional proteins will help in blocking downstream signal transducers which could result in reducing the bacterial virulence. The anti-virulence agent does not pose an immediate selective pressure on growing bacterium and thus reduces the pathogenicity without harming the target species. Here, we review exclusively, the growing emergence of multi-drug resistant (MDR) P. aeruginosa and the critical literature survey of QS inhibitors with their potential application of blocking P. aeruginosa infections.

15.
Heliyon ; 7(9): e07952, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34541355

RESUMEN

The corrosion inhibition property of selected small organic compounds was investigated using electrochemical measurements, including potentiodynamic polarization (PDP), linear polarization resistance (LPR), electrochemical impedance spectroscopy (EIS), and density functional theory (DFT) calculations. The inhibition efficiency (IE %) of the inhibitor on mild steel (MS) in 1 M HCl was then determined. Results show that the presence of the inhibitors resulted in decreased corrosion current density (I corr) values and increased polarization resistance (R p). Furthermore, the use of higher concentrations of inhibitors led to an increased inhibition efficiency. Tafel slopes and shifts in the E corr values suggested that the inhibitors tested are mixed-type inhibitors that form a protective layer on the surface of the substrate. Of the organic compound inhibitors tested, the inhibitor 4-ethylpyridine (EP) exhibited the highest R p values and inhibition efficiency values from the PDP, LPR, and EIS analyses, respectively. DFT calculations showed negative adsorption energies and confirmed the chemisorption of the inhibitors allowing for the formation of a hydrophobic protective film against corrosion and correlations between the quantum chemical values and electrochemical data were demonstrated. The results show the influence of the presence of electronegative O, S, and N atoms, as well as the role of aromatic rings in the promotion of surface protection by preventing aggressive ionic species from binding onto MS.

16.
Dalton Trans ; 50(24): 8292-8296, 2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34013949

RESUMEN

The crystal structure of an unprecedented silver complex of O-acetylsinigrin has shown chelating bonds of the sulfated thiohydroximate and an η2-bond of the ethylene moiety with Ag(i). Mechanistic studies on the formation and decomposition of the complex by the 1H NMR measurements and theoretical calculations with the DFT method indicated relevance to the glucosinolate degradation in biological systems.


Asunto(s)
Complejos de Coordinación/química , Glucosinolatos/química , Plata/química , Materiales Biomiméticos/química , Quelantes/química , Glicósido Hidrolasas/química , Modelos Moleculares
17.
ACS Omega ; 6(16): 10776-10789, 2021 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-34056232

RESUMEN

The metal-binding capabilities of the spiropyran family of molecular switches have been explored for several purposes from sensing to optical circuits. Metal-selective sensing has been of great interest for applications ranging from environmental assays to industrial quality control, but sensitive metal detection for field-based assays has been elusive. In this work, we demonstrate colorimetric copper sensing at low micromolar levels. Dimethylamine-functionalized spiropyran (SP1) was synthesized and its metal-sensing properties were investigated using UV-vis spectrophotometry. The formation of a metal complex between SP1 and Cu2+ was associated with a color change that can be observed by the naked eye as low as ≈6 µM and the limit of detection was found to be 0.11 µM via UV-vis spectrometry. Colorimetric data showed linearity of response in a physiologically relevant range (0-20 µM Cu2+) with high selectivity for Cu2+ ions over biologically and environmentally relevant metals such as Na+, K+, Mn2+, Ca2+, Zn2+, Co2+, Mg2+, Ni2+, Fe3+, Cd2+, and Pb2+. Since the color change accompanying SP1-Cu2+ complex formation could be detected at low micromolar concentrations, SP1 could be viable for field testing of trace Cu2+ ions.

18.
Zootaxa ; 4952(2): zootaxa.4952.2.2, 2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33903366

RESUMEN

The genus Thamnodynastes is the most diverse within the tribe Tachymenini, with an extensive and complex taxonomic history. The brief descriptions and lack of robust diagnostic characters are the main sources for identification errors and for the difficulty to assess the diversity estimates of the genus. The Thamnodynastes pallidus group was briefly designated to encompass the most arboreal species of the genus, with thinner bodies and longer tails: T. pallidus, T. longicaudus, T. sertanejo, and a fourth undescribed species. After its designation, no other paper addressed this group and its morphological variation, especially for the hemipenis, is still undetermined. After the analysis of all species of Thamnodynastes we were able to corroborate the distinctiveness of the T. pallidus group and to accurately diagnose its fourth species from the western portion of the Amazonia lowlands. The new species is distinguishable from all congeners, except T. sertanejo, by the absence of ventral longitudinal stripes, 17/17/11 dorsal scale rows, and dorsal dark brown blotches on the anterior third of the body. The new species is distinguished from T. sertanejo by the higher number of subcaudals, lower number of ventrals, and smaller body and head sizes. We also provide additional diagnostic features for the Thamnodynastes pallidus group, including new data on hemipenial variation. Finally, we briefly discuss the defensive behavior and morphological characters associated with arboreality in members of the T. pallidus species group.


Asunto(s)
Serpientes , Animales , Brasil , Piel , Serpientes/clasificación , Cola (estructura animal) , Árboles
19.
Surg Clin North Am ; 100(6): 1201-1214, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33128889

RESUMEN

Minimally invasive endoscopic resection procedures continue to evolve, with submucosal tunneling endoscopic resection (STER) being a durable option for en bloc resection of submucosal tumors. Whether STER can be effectively used for larger (>3.5 cm) lesions remains to be seen. STER-ET is a novel approach for removal of extraluminal tumors, but data are currently limited to support its use.


Asunto(s)
Resección Endoscópica de la Mucosa/métodos , Tumores del Estroma Gastrointestinal/cirugía , Membrana Mucosa/cirugía , Tracto Gastrointestinal Superior/cirugía , Mucosa Esofágica/cirugía , Mucosa Gástrica/cirugía , Neoplasias Gastrointestinales/cirugía , Humanos
20.
J Genet ; 992020.
Artículo en Inglés | MEDLINE | ID: mdl-33622987

RESUMEN

In heterozygote state, we interogressed three chromosomal segments of Drosophila koepferae in D. buzzatii. The effect of each introgression was evaluated in the fertility of the segmental males, quantifying the amount of offspring produced. Through specific crosses method, we generated Drosophila segmental isolines carrying specific chromosomal introgression segments. The introgressions were monitored cytogenetically by the method of molecular markers of chromosomal asynapsis. The statistical analysis showed that none of the three segments evaluated, introgressed individually or in pairs, as well as cis or trans, do not produce sterility in the segmental males, as determined by the normal productions of offspring. Additional introgressions using other larger segments show that when the introgressions reach a minimum size of 31.15%, they produce sterility. It is concluded that the hybrid sterility genes present in the three segments evaluated did not act in strong epistasis, but show a pattern of gradual additive behaviour by requiring a minimum threshold size to produce sterility. Finally, we also isolated the smallest introgressing segment that has been reported for these species (2.19%), and for the first time we have managed to place it in homozygous state (data not shown), so we are now in the process of evaluating the ability to these segments in homozygous state.


Asunto(s)
Cromosomas/genética , Proteínas de Drosophila/genética , Drosophila/genética , Marcadores Genéticos , Infertilidad/genética , Recombinación Genética , Aislamiento Reproductivo , Animales , Mapeo Cromosómico , Drosophila/clasificación , Femenino , Heterocigoto , Hibridación Genética , Masculino
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