Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 746
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Cell ; 163(1): 68-83, 2015 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-26365491

RESUMEN

cis-regulatory changes play a central role in morphological divergence, yet the regulatory principles underlying emergence of human traits remain poorly understood. Here, we use epigenomic profiling from human and chimpanzee cranial neural crest cells to systematically and quantitatively annotate divergence of craniofacial cis-regulatory landscapes. Epigenomic divergence is often attributable to genetic variation within TF motifs at orthologous enhancers, with a novel motif being most predictive of activity biases. We explore properties of this cis-regulatory change, revealing the role of particular retroelements, uncovering broad clusters of species-biased enhancers near genes associated with human facial variation, and demonstrating that cis-regulatory divergence is linked to quantitative expression differences of crucial neural crest regulators. Our work provides a wealth of candidates for future evolutionary studies and demonstrates the value of "cellular anthropology," a strategy of using in-vitro-derived embryonic cell types to elucidate both fundamental and evolving mechanisms underlying morphological variation in higher primates.


Asunto(s)
Epigenómica/métodos , Evolución Molecular , Mejoramiento Genético , Cresta Neural/citología , Pan troglodytes/genética , Animales , Embrión de Mamíferos/metabolismo , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Ratones , Ratones Transgénicos , Cresta Neural/metabolismo , Especificidad de la Especie
2.
Nature ; 609(7926): 265-268, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36071186

RESUMEN

Blazars are active galactic nuclei (AGN) with relativistic jets whose non-thermal radiation is extremely variable on various timescales1-3. This variability seems mostly random, although some quasi-periodic oscillations (QPOs), implying systematic processes, have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare4 in AGN and their nature is highly debated, explained by emitting plasma moving helically inside the jet5, plasma instabilities6,7 or orbital motion in an accretion disc7,8. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae (BL Lac) during a dramatic outburst in 2020 (ref. 9). BL Lac, the prototype of a subclass of blazars10, is powered by a 1.7 × 108 MSun (ref. 11) black hole in an elliptical galaxy (distance = 313 megaparsecs (ref. 12)). Our observations show QPOs of optical flux and linear polarization, and γ-ray flux, with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities6 near a recollimation shock about 5 parsecs (pc) from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array (VLBA) image.

3.
Artículo en Inglés | MEDLINE | ID: mdl-39154658

RESUMEN

BACKGROUND: The bead-based epitope assay has been used to identify epitope-specific (es) antibodies and successfully used to diagnose clinical allergy to milk, egg, and peanut. OBJECTIVE: We sought to identify es-IgE, es-IgG4, and es-IgG1 of wheat proteins and determine the optimal peptides to differentiate wheat-allergic from wheat-tolerant using the bead-based epitope assay. METHODS: Children and adolescents who underwent an oral food challenge to confirm their wheat allergy status were enrolled. Seventy-nine peptides from α-/ß-gliadin, γ-gliadin, ω-5-gliadin, and high- and low-molecular-weight glutenin were commercially synthesized and coupled to LumAvidin beads (Luminex Corporation, Austin, Tex). Machine learning methods were used to identify diagnostic epitopes, and performance was evaluated using the DeLong test. RESULTS: The analysis included 122 children (83 wheat-allergic and 39 wheat-tolerant; 57.4% male). Machine learning coupled with simulations identified wheat es-IgE, but not es-IgG4 or es-IgG1, to be the most informative for diagnosing wheat allergy. Higher es-IgE binding intensity correlated with the severity of allergy phenotypes, with wheat anaphylaxis exhibiting the highest es-IgE binding intensity. In contrast, wheat-dependent exercise-induced anaphylaxis showed lower es-IgG1 binding intensity than did all the other groups. A set of 4 informative epitopes from ω-5-gliadin and γ-gliadin were the best predictors of wheat allergy, with an area under the curve of 0.908 (sensitivity, 83.4%; specificity, 88.4%), higher than the performance exhibited by wheat-specific IgE (area under the curve = 0.646; P < .001). The predictive ability of our model was confirmed in an external cohort of 71 patients (29 allergic, 42 nonallergic), with an area under the curve of 0.908 (sensitivity, 75.9%; specificity, 90.5%). CONCLUSIONS: The wheat bead-based epitope assay demonstrated greater diagnostic accuracy compared with existing specific IgE tests for wheat allergy.

4.
J Allergy Clin Immunol ; 154(3): 690-697.e4, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38821318

RESUMEN

BACKGROUND: Reaction threshold and severity in food allergy are difficult to predict, and noninvasive predictors are lacking. OBJECTIVE: We sought to determine the relationships between pre-challenge levels of peanut (PN)-specific antibodies in saliva and reaction threshold, severity, and organ-specific symptoms during PN allergic reactions. METHODS: We measured PN-specific antibody levels in saliva collected from 127 children with suspected PN allergy before double-blind, placebo-controlled PN challenges in which reaction threshold, severity, and symptoms were rigorously characterized. Low threshold (LT) PN allergy was defined as reaction to <300 mg of PN protein cumulatively consumed. A consensus severity grading system was used to grade severity. We analyzed associations between antibody levels and reaction threshold, severity, and organ-specific symptoms. RESULTS: Among the 127 children, those with high pre-challenge saliva PN IgE had higher odds of LT PN allergy (odds ratio [OR] 3.9, 95% CI 1.6-9.5), while those with high saliva PN IgA:PN IgE ratio or PN IgG4:PN IgE ratio had lower odds of LT PN allergy (OR 0.3, 95% CI 0.1-0.8; OR 0.4, 95% CI 0.2-0.9). Children with high pre-challenge saliva PN IgG4 had lower odds of severe PN reactions (OR 0.4, 95% CI 0.2-0.9). Children with high saliva PN IgE had higher odds of respiratory symptoms (OR 8.0, 95% CI 2.2-26.8). Saliva PN IgE modestly correlated with serum PN IgE levels (Pearson r = 0.31, P = .0004). High and low saliva PN IgE levels further distinguished reaction threshold and severity in participants stratified by serum PN IgE, suggesting endotypes. CONCLUSIONS: Saliva PN antibodies could aid in noninvasive risk stratification of PN allergy threshold, severity, and organ-specific symptoms.


Asunto(s)
Inmunoglobulina E , Hipersensibilidad al Cacahuete , Saliva , Índice de Severidad de la Enfermedad , Humanos , Hipersensibilidad al Cacahuete/inmunología , Saliva/inmunología , Femenino , Masculino , Inmunoglobulina E/inmunología , Inmunoglobulina E/sangre , Niño , Preescolar , Alérgenos/inmunología , Arachis/inmunología , Inmunoglobulina A/inmunología , Método Doble Ciego , Inmunoglobulina G/inmunología , Inmunoglobulina G/sangre , Adolescente
5.
J Allergy Clin Immunol ; 153(6): 1721-1728, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38272374

RESUMEN

BACKGROUND: Reaction thresholds in peanut allergy are highly variable. Elucidating causal relationships between molecular and cellular processes associated with variable thresholds could point to therapeutic pathways for raising thresholds. OBJECTIVE: The aim of this study was to characterize molecular and cellular systemic processes associated with reaction threshold in peanut allergy and causal relationships between them. METHODS: A total of 105 children aged 4 to 14 years with suspected peanut allergy underwent double-blind, placebo-controlled food challenge to peanut. The cumulative peanut protein quantity eliciting allergic symptoms was considered the reaction threshold for each child. Peripheral blood samples collected at 0, 2, and 4 hours after challenge start were used for RNA sequencing, whole blood staining, and cytometry. Statistical and network analyses were performed to identify associations and causal mediation between the molecular and cellular profiles and peanut reaction threshold. RESULTS: Within the cohort (N = 105), 81 children (77%) experienced allergic reactions after ingesting varying quantities of peanut, ranging from 43 to 9043 mg of cumulative peanut protein. Peripheral blood expression of transcripts (eg, IGF1R [false discovery rate (FDR) = 5.4e-5] and PADI4 [FDR = 5.4e-5]) and neutrophil abundance (FDR = 9.5e-4) were associated with peanut threshold. Coexpression network analyses revealed that the threshold-associated transcripts were enriched in modules for FcγR-mediated phagocytosis (FDR = 3.2e-3) and Toll-like receptor (FDR = 1.4e-3) signaling. Bayesian network, key driver, and causal mediation analyses identified key drivers (AP5B1, KLHL21, VASP, TPD52L2, and IGF2R) within these modules that are involved in bidirectional causal mediation relationships with neutrophil abundance. CONCLUSION: Key driver transcripts in FcγR-mediated phagocytosis and Toll-like receptor signaling interact bidirectionally with neutrophils in peripheral blood and are associated with reaction threshold in peanut allergy.


Asunto(s)
Hipersensibilidad al Cacahuete , Humanos , Hipersensibilidad al Cacahuete/inmunología , Niño , Preescolar , Masculino , Femenino , Adolescente , Transcriptoma , Arachis/inmunología , Alérgenos/inmunología , Método Doble Ciego , Citometría de Flujo
6.
Allergy ; 2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38796780

RESUMEN

BACKGROUND: Allergic rhinitis is a common inflammatory condition of the nasal mucosa that imposes a considerable health burden. Air pollution has been observed to increase the risk of developing allergic rhinitis. We addressed the hypotheses that early life exposure to air toxics is associated with developing allergic rhinitis, and that these effects are mediated by DNA methylation and gene expression in the nasal mucosa. METHODS: In a case-control cohort of 505 participants, we geocoded participants' early life exposure to air toxics using data from the US Environmental Protection Agency, assessed physician diagnosis of allergic rhinitis by questionnaire, and collected nasal brushings for whole-genome DNA methylation and transcriptome profiling. We then performed a series of analyses including differential expression, Mendelian randomization, and causal mediation analyses to characterize relationships between early life air toxics, nasal DNA methylation, nasal gene expression, and allergic rhinitis. RESULTS: Among the 505 participants, 275 had allergic rhinitis. The mean age of the participants was 16.4 years (standard deviation = 9.5 years). Early life exposure to air toxics such as acrylic acid, phosphine, antimony compounds, and benzyl chloride was associated with developing allergic rhinitis. These air toxics exerted their effects by altering the nasal DNA methylation and nasal gene expression levels of genes involved in respiratory ciliary function, mast cell activation, pro-inflammatory TGF-ß1 signaling, and the regulation of myeloid immune cell function. CONCLUSIONS: Our results expand the range of air pollutants implicated in allergic rhinitis and shed light on their underlying biological mechanisms in nasal mucosa.

7.
Langmuir ; 40(11): 5632-5638, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38449101

RESUMEN

The article presents a high-productivity laser-structuring method combined with a hydrophobic post-treatment to create zone-structured surfaces with a decreasing wetting angle on AISI 304 stainless steel surfaces. We have investigated the impact of laser processing modes and hydrophobic substances on wetting and hysteresis angles and successfully demonstrated autonomous droplet movement over this zone-structured surface. A critical condition for autonomous fluid flow is the need for the drop to touch the boundary between the two zones. This can be achieved by settling the droplet directly on the boundary of the two zones or by using droplets whose surface contact diameter is on the order of magnitude or higher than the zone size. The zone-structured surface showed reusability, maintaining its properties even after 30 droplet passages. The zone-structured surfaces with a decreasing wetting angle can be used for moving a droplet along a complex trajectory as well as for mixing various liquids.

8.
Eur J Haematol ; 2024 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-39400388

RESUMEN

In a randomized phase II trial (AMLSG 14-09, NCT00867672) of elderly, newly diagnosed AML patients, ATRA combined with decitabine (DEC) significantly improved the overall response rate (ORR) and survival also in patients with adverse-risk genetics, without adding toxicity. We performed a post hoc analysis to determine the predictive impact of TP53 status. Despite a nominally higher ORR, the clinically meaningful survival benefit when adding ATRA to DEC was diminished, but not completely negated, in TP53-mutated patients. Indeed, 2 out of 14 TP53-mutated patients (14%) randomized to a DEC + ATRA-containing regimen lived for > 36 months. Further studies of ATRA combined with hypomethylating agents appear warranted in non-M3 AML patients ineligible for HMA/venetoclax therapy. Trial Registration: ClinicalTrials.gov identifier: NCT00867672.

9.
Inflammopharmacology ; 32(1): 149-228, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38212535

RESUMEN

Diabetes mellitus is a prevalent cause of mortality worldwide and can lead to several secondary issues, including DWs, which are caused by hyperglycemia, diabetic neuropathy, anemia, and ischemia. Roughly 15% of diabetic patient's experience complications related to DWs, with 25% at risk of lower limb amputations. A conventional management protocol is currently used for treating diabetic foot syndrome, which involves therapy using various substances, such as bFGF, pDGF, VEGF, EGF, IGF-I, TGF-ß, skin substitutes, cytokine stimulators, cytokine inhibitors, MMPs inhibitors, gene and stem cell therapies, ECM, and angiogenesis stimulators. The protocol also includes wound cleaning, laser therapy, antibiotics, skin substitutes, HOTC therapy, and removing dead tissue. It has been observed that treatment with numerous plants and their active constituents, including Globularia Arabica, Rhus coriaria L., Neolamarckia cadamba, Olea europaea, Salvia kronenburgii, Moringa oleifera, Syzygium aromaticum, Combretum molle, and Myrtus communis, has been found to promote wound healing, reduce inflammation, stimulate angiogenesis, and cytokines production, increase growth factors production, promote keratinocyte production, and encourage fibroblast proliferation. These therapies may also reduce the need for amputations. However, there is still limited information on how to prevent and manage DWs, and further research is needed to fully understand the role of alternative treatments in managing complications of DWs. The conventional management protocol for treating diabetic foot syndrome can be expensive and may cause adverse side effects. Alternative therapies, such as medicinal plants and green synthesis of nano-formulations, may provide efficient and affordable treatments for DWs.


Asunto(s)
Terapias Complementarias , Diabetes Mellitus , Pie Diabético , Humanos , Pie Diabético/tratamiento farmacológico , Cicatrización de Heridas , Citocinas/metabolismo , Inflamación
10.
Khirurgiia (Mosk) ; (7): 36-44, 2024.
Artículo en Ruso | MEDLINE | ID: mdl-39008696

RESUMEN

OBJECTIVE: To analyze archival data on emergency hospitalization of patients with Crohn's disease, indications for surgical treatment, structure of surgeries, localization of gastrointestinal lesions and relationship between diagnostic period and surgical treatment. MATERIAL AND METHODS: A retrospective analysis of medical records of patients with Crohn's disease in 3 large hospitals was performed over the past 6 years. We estimated cases of surgical treatment, localization of gastrointestinal lesions, clinical and laboratory parameters of patients, period between clinical manifestation and diagnosis, as well as outcomes of disease depending on duration of diagnostic searching. CONCLUSION: Duration of diagnostic searching in patients with Crohn's disease is a significant predictor of complications and surgical treatment.


Asunto(s)
Enfermedad de Crohn , Humanos , Enfermedad de Crohn/diagnóstico , Enfermedad de Crohn/cirugía , Femenino , Masculino , Adulto , Estudios Retrospectivos , Federación de Rusia/epidemiología , Persona de Mediana Edad , Factores de Tiempo , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/etiología , Resultado del Tratamiento
11.
Vestn Oftalmol ; 140(2): 102-111, 2024.
Artículo en Ruso | MEDLINE | ID: mdl-38742506

RESUMEN

Dry eye disease (DED) is pathogenetically based on inflammation of the ocular surface. A step-by-step approach to DED treatment involves early initiation of anti-inflammatory therapy, including instillation of cyclosporine A (CsA). However, recommendations for the use of topical CsA in clinical practice are limited. This article presents an expert consensus on practical recommendations for the management of patients with DED, including indications, time of initiation and duration of CsA therapy, comparison of CsA forms currently registered in the Russian Federation, as well as issues of patient education.


Asunto(s)
Ciclosporina , Emulsiones , Humanos , Administración Oftálmica , Ciclosporina/administración & dosificación , Síndromes de Ojo Seco/tratamiento farmacológico , Síndromes de Ojo Seco/etiología , Inmunosupresores/administración & dosificación , Soluciones Oftálmicas/administración & dosificación , Resultado del Tratamiento , Xeroftalmia/etiología , Xeroftalmia/tratamiento farmacológico , Xeroftalmia/diagnóstico
12.
Artículo en Ruso | MEDLINE | ID: mdl-38349689

RESUMEN

The article considers organizational issues of cervical cancer screening in the Russian Federation. In particular, experience of implementation of the Project "HPV testing within the framework of combined cervical cancer screening (HPV and cytologic screening) in the Republic of Bashkortostan is considered. The cervical cancer is a widespread disease that requires early diagnosis and timely medical care. The main aspects of organization of medical care of patients with gynecological diseases in relevant normative legal regulatory documents are described. The algorithm and scheme of routing patients with suspected cervical cancer and with this disease are presented. The study covered more than 60,000 women aged 30-39 years from 14 medical organizations of Ufa. Such methods as sociological, statistical, analytical, content-analysis and organizational experiment were applied. The study permitted to substantiate and to approve both the Project "HPV testing as part of combined screening for cervical cancer (HPV screening and cytologic screening) and the algorithm of combined screening of cervical cancer during preventive examinations of female adult population aged 30-39 years of the Republic of Bashkortostan. The scheme was developed for routing patients with suspected cervical cancer or diagnosed disease to medical organizations for timely medical care support. By implementing developed routing and screening scheme for patients at risk of developing cervical cancer, as well as those who already suffer this pathology, it is possible to improve quality of organization and delivery of medical care, to reduce morbidity, mortality and disability because of this pathology and to assure early diagnosis and prevention of cervical cancer.


Asunto(s)
Neoplasias de Cabeza y Cuello , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Adulto , Humanos , Femenino , Detección Precoz del Cáncer , Baskiria , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/epidemiología
13.
J Comput Chem ; 44(10): 1016-1030, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-36533526

RESUMEN

Efficacy and safety are among the most desirable characteristics of an ideal drug. The tremendous increase in computing power and the entry of artificial intelligence into the field of computational drug design are accelerating the process of identifying, developing, and optimizing potential drugs. Here, we present novel approach to design new molecules with desired properties. We combined various neural networks and linear regression algorithms to build models for cytotoxicity and anti-HIV activity based on Continual Molecular Interior analysis (CoMIn) and Cinderella's Shoe (CiS) derived molecular descriptors. After validating the reliability of the models, a genetic algorithm was coupled with the Des-Pot Grid algorithm to generate new molecules from a predefined pool of molecular fragments and predict their bioactivity and cytotoxicity. This combination led to the proposal of 16 hit molecules with high anti-HIV activity and low cytotoxicity. The anti-SARS-CoV-2 activity of the hits was predicted.


Asunto(s)
Inteligencia Artificial , COVID-19 , Humanos , Reproducibilidad de los Resultados , Relación Estructura-Actividad Cuantitativa , Algoritmos , Simulación del Acoplamiento Molecular
14.
Ann Allergy Asthma Immunol ; 131(6): 759-765.e3, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37659472

RESUMEN

BACKGROUND: Patients exquisitely sensitive to cashew/pistachio are at risk for allergic reactions to citrus seeds and pectin. OBJECTIVE: In this study, we sought to evaluate whether pectin is contaminated with citrus seeds, to identify a culprit antigen in citrus seeds, and to assess for cross-reactivity among allergens in citrus seeds, citrus pectin, and cashew or pistachio. METHODS: Proteins from orange seed coats, orange seed endosperms, lemon seeds, grapefruit seeds, citrus pectin, apple pectin, and grapefruit pectin were extracted. Protein concentrations in all extracts were determined and visualized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis technique. Immunoglobulin E-binding capacity was determined with Western blot analyses and tandem mass spectrometry for the identification of the culprit allergen in citrus seeds and pectin. RESULTS: In subjects with citrus seed, pectin, and cashew allergies, there was strong immunoglobulin E-reactivity to bands between 17 to 28 kDa and 28 to 38 kDa. The tandem mass spectrometry analysis of these bands indicated the presence of citrin as the culprit allergen. Citrin and Ana o 2 are both 11S globulins belonging to the cupin superfamily, and significant homology was found between these proteins. CONCLUSION: Citrus pectin may be contaminated with citrus seeds. Citrin, a newly identified allergen in citrus seeds, seems to be the culprit antigen in citrus seeds and contaminated citrus pectin. Citrin is highly homologous with Ana o 2 in cashew and Pis v 2 in pistachio, suggesting potential for cross-reactivity and providing an explanation for co-allergenicity of cashew or pistachio, citrus seeds, and citrus pectin.


Asunto(s)
Anacardium , Citrus , Hipersensibilidad a los Alimentos , Hipersensibilidad a la Nuez , Pistacia , Humanos , Alérgenos/química , Citrus/química , Inmunoglobulina E , Pectinas , Pistacia/química , Proteínas de Plantas , Semillas/química
15.
J Biochem Mol Toxicol ; 37(4): e23295, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36582145

RESUMEN

We report a series of hybrid oxoazetidine conjugated thiazoles as epidermal growth factor receptor (EGFR) inhibitors, which were synthesized and tested using a variety of in silico and in vitro studies. The compounds were found to be active against breast and hepatic cancer cell lines, with Compounds 7a, 7b, and 7e being the most potent ones. The derivatives were also evaluated for molecular docking and complementarity studies to explicate fundamental substituent groups essential for their bioactivity. Moreover, the structural activity relationship of the analogues was performed for future compound optimization. These studies advocated that the analogues have a high affinity towards EGFR with favorable anticancer potential. The study advised that the derivatives have potency against breast and hepatic cancer and can assist as an initial scaffold for further development of anti-EGFR compounds.


Asunto(s)
Antineoplásicos , Neoplasias Hepáticas , Humanos , Estructura Molecular , Simulación del Acoplamiento Molecular , Antineoplásicos/química , Tiazoles/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Relación Estructura-Actividad , Proliferación Celular , Inhibidores de Proteínas Quinasas/farmacología , Relación Dosis-Respuesta a Droga
16.
Nature ; 552(7685): 374-377, 2017 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-29211720

RESUMEN

Blazars are active galactic nuclei, which are powerful sources of radiation whose central engine is located in the core of the host galaxy. Blazar emission is dominated by non-thermal radiation from a jet that moves relativistically towards us, and therefore undergoes Doppler beaming. This beaming causes flux enhancement and contraction of the variability timescales, so that most blazars appear as luminous sources characterized by noticeable and fast changes in brightness at all frequencies. The mechanism that produces this unpredictable variability is under debate, but proposed mechanisms include injection, acceleration and cooling of particles, with possible intervention of shock waves or turbulence. Changes in the viewing angle of the observed emitting knots or jet regions have also been suggested as an explanation of flaring events and can also explain specific properties of blazar emission, such as intra-day variability, quasi-periodicity and the delay of radio flux variations relative to optical changes. Such a geometric interpretation, however, is not universally accepted because alternative explanations based on changes in physical conditions-such as the size and speed of the emitting zone, the magnetic field, the number of emitting particles and their energy distribution-can explain snapshots of the spectral behaviour of blazars in many cases. Here we report the results of optical-to-radio-wavelength monitoring of the blazar CTA 102 and show that the observed long-term trends of the flux and spectral variability are best explained by an inhomogeneous, curved jet that undergoes changes in orientation over time. We propose that magnetohydrodynamic instabilities or rotation of the twisted jet cause different jet regions to change their orientation and hence their relative Doppler factors. In particular, the extreme optical outburst of 2016-2017 (brightness increase of six magnitudes) occurred when the corresponding emitting region had a small viewing angle. The agreement between observations and theoretical predictions can be seen as further validation of the relativistic beaming theory.

17.
Chem Biodivers ; 20(4): e202300061, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36824028

RESUMEN

Metal complexes in cancer therapy have attracted much interest mainly because metals exhibit unique characteristics, such as redox activity, metal-ligand interaction, structure and bonding, Lewis acid properties etc. In 1965, Barnett Rosenberg serendipitously discovered the metal-based compound cisplatin, an outstanding breakthrough in the history of metal-based anticancer complexes and led to a new area of anticancer drug discovery. Many metal-based compounds have been studied for their potential anticancer properties. Some of these compounds have FDA approval for clinical use, while others are now undergoing clinical trials for cancer therapy and detection. In the present study, we have highlighted the primary mode of action of metallic complexes and all FDA-approved/under clinical trial drugs with reference to cancer treatment. This review also focuses on recent progress on metal-based complexes such as platinum, ruthenium, iron, etc. with potential anticancer activities.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Neoplasias , Rutenio , Humanos , Complejos de Coordinación/farmacología , Complejos de Coordinación/uso terapéutico , Complejos de Coordinación/química , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Antineoplásicos/química , Neoplasias/tratamiento farmacológico , Cisplatino , Rutenio/química
18.
Chem Biodivers ; 20(8): e202300719, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37312449

RESUMEN

In hepatic cancer, precancerous nodules account for damage and inflammation in liver cells. Studies have proved that phyto-compounds based on biosynthetic metallic nanoparticles display superior action against hepatic tumors. This study targeted the synthesis of genistein-fortified zinc ferrite nanoparticles (GENP) trailed by anticancer activity assessment against diethylnitrosamine and N-acetyl-2-aminofluorene induced hepatic cancer. The process of nucleation was confirmed by UV/VIS spectrophotometry, X-ray beam diffraction, field-emission scanning electron microscopy, and FT-IR. An in vitro antioxidant assay illustrated that the leaves of Pterocarpus mildbraedii have strong tendency as a reductant and, in the nanoformulation synthesis, as a natural capping agent. A MTT assay confirmed that GENP have a strong selective cytotoxic potential against HepG2 cancer cells. In silico studies of genistein exemplified the binding tendency towards human matrix metalloproteinase comparative to the standard drug marimastat. An in vivo anticancer evaluation showed that GENP effectively inhibit the growth of hepatic cancer by interfering with hepatic and non-hepatic biochemical markers.


Asunto(s)
Neoplasias Hepáticas , Nanopartículas del Metal , Humanos , Zinc , Genisteína/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Neoplasias Hepáticas/tratamiento farmacológico , Nanopartículas del Metal/química , Extractos Vegetales/química , Difracción de Rayos X , Tecnología Química Verde , Antibacterianos/farmacología
19.
J Allergy Clin Immunol ; 150(5): 1232-1236, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35718139

RESUMEN

BACKGROUND: Genetic predisposition increases risk for asthma, and distinct nasal microbial compositions are associated with asthma. Host genetics might shape nasal microbiome composition. OBJECTIVE: We examined associations between host genetics and nasal microbiome composition. METHODS: Nasal samples were collected from 584 participants from the Mount Sinai Health System, New York. Seventy-seven follow-up samples were collected from a subset of 40 participants. 16S rRNA sequencing and RNA sequencing were performed on nasal samples. Beta diversity was calculated, variant calling on RNA sequencing data was performed, and genetic relatedness between individuals was determined. Using linear regression models, we tested for associations between genetic relatedness and nasal microbiome composition. RESULTS: The median age of the cohort was 14.6 (interquartile range 11.2-19.5) years, with participants representing diverse ancestries and 52.7% of the cohort being female. For participants who provided follow-up samples, the median time between samples was 5.1 (interquartile range 1.4-7.2) months. Nasal microbiome composition similarity as reflected by beta diversity was significantly higher within subjects over time versus between subjects (coefficient = 0.091, P = 2.84-7). There was no significant association between genetic relatedness and beta diversity (coefficient = -0.05, P = .29). Additional analyses exploring the relationship between beta diversity and genetic variance yielded similar results. CONCLUSION: Host genetics has little influence on nasal microbiome composition.


Asunto(s)
Asma , Microbiota , Humanos , Femenino , Niño , Adolescente , Adulto Joven , Adulto , Masculino , ARN Ribosómico 16S/genética , Microbiota/genética , Nariz , Estudios de Cohortes
20.
Int J Mol Sci ; 24(15)2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37569666

RESUMEN

In the present article, the possible mitigation of the toxic effect of imidacloprid low-concentration chronic exposure on Danio rerio by the probiotic strain Lactobacillus brevis 47f (1 × 108 CFU/g) was examined. It was found that even sublethal concentration (2500 µg/L) could lead to the death of some fish during the 60-day chronic experiment. However, the use of Lactobacillus brevis 47f partially reduced the toxic effects, resulting in an increased survival rate and a significant reduction of morphohistological lesions in the intestines and kidneys of Danio rerio. The kidneys were found to be the most susceptible organ to toxic exposure, showing significant disturbances. Calculation of the histopathological index, measurement of morphometric parameters, and analysis of principal components revealed the most significant parameters affected by the combined action of imidacloprid and Lactobacillus brevis 47f. This effect of imidacloprid and the probiotic strain had a multidirectional influence on various pro/anti-inflammatory cytokines (IL-1ß, TNF-α, IL-6, IL-8). Therefore, the results suggest the possibility of further studying the probiotic strain Lactobacillus brevis 47f as a strain that reduces the toxic effects of xenobiotics. Additionally, the study established the possibility of using imidacloprid as a model toxicant to assess the detoxification ability of probiotics on the kidney and gastrointestinal tract of fish.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA