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1.
Numer Algorithms ; 93(1): 103-130, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37038541

RESUMEN

In this work, we study resolvent splitting algorithms for solving composite monotone inclusion problems. The objective of these general problems is finding a zero in the sum of maximally monotone operators composed with linear operators. Our main contribution is establishing the first primal-dual splitting algorithm for composite monotone inclusions with minimal lifting. Specifically, the proposed scheme reduces the dimension of the product space where the underlying fixed point operator is defined, in comparison to other algorithms, without requiring additional evaluations of the resolvent operators. We prove the convergence of this new algorithm and analyze its performance in a problem arising in image deblurring and denoising. This work also contributes to the theory of resolvent splitting algorithms by extending the minimal lifting theorem recently proved by Malitsky and Tam to schemes with resolvent parameters.

2.
Mol Med ; 28(1): 39, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35365098

RESUMEN

BACKGROUND: Bladder cancer (BC) has the highest per-patient cost of all cancer types. Hence, we aim to develop a non-invasive, point-of-care tool for the diagnostic and molecular stratification of patients with BC based on combined microRNAs (miRNAs) and surface-enhanced Raman spectroscopy (SERS) profiling of urine. METHODS: Next-generation sequencing of the whole miRNome and SERS profiling were performed on urine samples collected from 15 patients with BC and 16 control subjects (CTRLs). A retrospective cohort (BC = 66 and CTRL = 50) and RT-qPCR were used to confirm the selected differently expressed miRNAs. Diagnostic accuracy was assessed using machine learning algorithms (logistic regression, naïve Bayes, and random forest), which were trained to discriminate between BC and CTRL, using as input either miRNAs, SERS, or both. The molecular stratification of BC based on miRNA and SERS profiling was performed to discriminate between high-grade and low-grade tumors and between luminal and basal types. RESULTS: Combining SERS data with three differentially expressed miRNAs (miR-34a-5p, miR-205-3p, miR-210-3p) yielded an Area Under the Curve (AUC) of 0.92 ± 0.06 in discriminating between BC and CTRL, an accuracy which was superior either to miRNAs (AUC = 0.84 ± 0.03) or SERS data (AUC = 0.84 ± 0.05) individually. When evaluating the classification accuracy for luminal and basal BC, the combination of miRNAs and SERS profiling averaged an AUC of 0.95 ± 0.03 across the three machine learning algorithms, again better than miRNA (AUC = 0.89 ± 0.04) or SERS (AUC = 0.92 ± 0.05) individually, although SERS alone performed better in terms of classification accuracy. CONCLUSION: miRNA profiling synergizes with SERS profiling for point-of-care diagnostic and molecular stratification of BC. By combining the two liquid biopsy methods, a clinically relevant tool that can aid BC patients is envisaged.


Asunto(s)
MicroARNs , Neoplasias de la Vejiga Urinaria , Teorema de Bayes , Biomarcadores de Tumor/genética , Humanos , Biopsia Líquida , MicroARNs/genética , Sistemas de Atención de Punto , Estudios Retrospectivos , Neoplasias de la Vejiga Urinaria/diagnóstico , Neoplasias de la Vejiga Urinaria/genética
3.
Nature ; 538(7625): 397-401, 2016 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-27706135

RESUMEN

Transient, multi-protein complexes are important facilitators of cellular functions. This includes the chaperome, an abundant protein family comprising chaperones, co-chaperones, adaptors, and folding enzymes-dynamic complexes of which regulate cellular homeostasis together with the protein degradation machinery. Numerous studies have addressed the role of chaperome members in isolation, yet little is known about their relationships regarding how they interact and function together in malignancy. As function is probably highly dependent on endogenous conditions found in native tumours, chaperomes have resisted investigation, mainly due to the limitations of methods needed to disrupt or engineer the cellular environment to facilitate analysis. Such limitations have led to a bottleneck in our understanding of chaperome-related disease biology and in the development of chaperome-targeted cancer treatment. Here we examined the chaperome complexes in a large set of tumour specimens. The methods used maintained the endogenous native state of tumours and we exploited this to investigate the molecular characteristics and composition of the chaperome in cancer, the molecular factors that drive chaperome networks to crosstalk in tumours, the distinguishing factors of the chaperome in tumours sensitive to pharmacologic inhibition, and the characteristics of tumours that may benefit from chaperome therapy. We find that under conditions of stress, such as malignant transformation fuelled by MYC, the chaperome becomes biochemically 'rewired' to form a network of stable, survival-facilitating, high-molecular-weight complexes. The chaperones heat shock protein 90 (HSP90) and heat shock cognate protein 70 (HSC70) are nucleating sites for these physically and functionally integrated complexes. The results indicate that these tightly integrated chaperome units, here termed the epichaperome, can function as a network to enhance cellular survival, irrespective of tissue of origin or genetic background. The epichaperome, present in over half of all cancers tested, has implications for diagnostics and also provides potential vulnerability as a target for drug intervention.


Asunto(s)
Chaperonas Moleculares/metabolismo , Complejos Multiproteicos/metabolismo , Neoplasias/metabolismo , Neoplasias/patología , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Descubrimiento de Drogas , Femenino , Genes myc/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Proteínas HSP90 de Choque Térmico/metabolismo , Humanos , Ratones , Chaperonas Moleculares/antagonistas & inhibidores , Complejos Multiproteicos/antagonistas & inhibidores , Complejos Multiproteicos/química , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Especificidad de Órganos
4.
Adv Exp Med Biol ; 1243: 87-99, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32297213

RESUMEN

The chaperome is a large family of proteins composed of chaperones, co-chaperones and a multitude of other factors. Elegant studies in yeast and other organisms have paved the road to how we currently understand the complex organization of this large family into protein networks. The goal of this chapter is to provide an overview of chaperome networks in cancer cells, with a focus on two cellular states defined by chaperome network organization. One state characterized by chaperome networks working in isolation and with little overlap, contains global chaperome networks resembling those of normal, non-transformed, cells. We propose that in this state, redundancy in chaperome networks results in a tumor type unamenable for single-agent chaperome therapy. The second state comprises chaperome networks interconnected in response to cellular stress, such as MYC hyperactivation. This is a state where no redundant pathways can be deployed, and is a state of vulnerability, amenable for chaperome therapy. We conclude by proposing a change in how we discover and implement chaperome inhibitor strategies, and suggest an approach to chaperome therapy where the properties of chaperome networks, rather than genetics or client proteins, are used in chaperome inhibitor implementation.


Asunto(s)
Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Chaperonas Moleculares/antagonistas & inhibidores , Chaperonas Moleculares/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Humanos , Neoplasias/patología
5.
Acta Endocrinol (Buchar) ; 16(2): 208-215, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33029238

RESUMEN

CONTEXT: Incidentally discovered solid adrenal tumors must be evaluated from two points of view: the risk of malignancy and the secretory feature. OBJECTIVE: Our aim was to evaluate the surgical technique option in relation with clinical and histopathologic features. DESIGN: We performed a retrospective study that included patients with adrenal gland tumors. SUBJECTS AND METHODS: All patients were operated between 2012 and 2019 by the same surgical team in a single center. RESULTS: The batch included 102 patients with adrenal tumors operated through open surgery (OS, n=41) and laparoscopic surgery (LS, n=61). Tumor localization was especially on the right adrenal gland (n=52, 50.98%). Primary origin of the adrenal gland tumors was in 82 cases (80.39%) and a metastatic origin in 16 cases. Average dimension for surgical resected tumors was 4.02 cm (0.9-12 cm) for the LS group as compared to 7.22 cm (1.3-19 cm) for OS group with a predominant type of surgery represented by adrenalectomy and a conversion rate of 2.94%. The hospital stay was 7.22 days (5-12 days) in the LS group versus 12.72 days (6-57 days) in OS group with significant differences (p<0.01). Also, the postoperative recovery was significantly different (6.5 days versus 2.62 days, p<0.01). CONCLUSION: Laparoscopic approach represents the gold standard in adrenal gland tumors less than five centimeters in size. Adrenalectomy is mostly performed by LS and adenoma is the most frequent histopathologic type, while pheochromocytoma is operated through OS. LS has a significantly reduced hospitalization and postoperative stay compared to OS.

6.
Nanotechnology ; 30(5): 055702, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30511667

RESUMEN

Using internal photoemission of electrons from few-monolayer thin MoS2 films into SiO2 we found that the MoS2 layer transfer processing perturbs electroneutrality of the interface, leading to an increase of the electron barrier height by ≈0.5-1 eV as compared to the case of the same films synthesized directly on SiO2. This effect is associated with the formation of an interface dipole, tentatively ascribed to interaction of H2O molecules with the SiO2 surface resulting in the incorporation of silanol (SiOH) groups. This violation of the interface electroneutrality may account for additional electron scattering in ultrathin transferred films and threshold voltage instabilities. Post-transfer annealing in H2S is shown to reduce the transfer-induced interface degradation.

7.
J Chem Phys ; 150(10): 104703, 2019 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-30876349

RESUMEN

Monolayer-thin WS2 with (0002) texture grows by chemical vapor deposition (CVD) from gas-phase precursors WF6 and H2S at a deposition temperature of 450 °C on 300 mm Si wafers covered with an amorphous Al2O3 starting surface. We investigate the growth and nucleation mechanism during the CVD process by analyzing the morphology of the WS2 crystals. The CVD process consists of two distinct growth regimes. During (i) the initial growth regime, a fast and self-limiting reaction of the CVD precursors with the Al2O3 starting surface forms predominantly monolayer-thin WS2 crystals and AlF3 crystals that completely cover the starting surface. During (ii) the steady-state growth regime, a much slower, anisotropic reaction on the bottom, first WS2 layer proceeds with the next WS2 layer growing preferentially in the lateral dimensions. We propose that the precursor adsorption reaction rate strongly diminishes when the precursors have no more access to the Al2O3 surface as soon as the WS2 layer completely covers the Al2O3 surface and that the WS2 crystal basal planes and AlF3 crystals have a low reactivity for WF6 adsorption at 450 °C. Nonetheless, a second layer of WS2 starts to form before the first WS2 layer completely covers the starting surface, albeit the surface coverage of the second layer is low (<20%, after 25 min of CVD reaction). During the steady-state growth regime, predominantly the WS2 crystals in the second monolayer continue to grow in lateral dimensions up to ∼40 nm. These crystals reach larger lateral dimensions compared to the crystals in the bottom, first layer due to low reactivity for WF6 adsorption on the WS2 basal plane compared to Al2O3. Presumably, they grow laterally by precursor species that adsorb on and diffuse across the WS2 surface, before being incorporated at the more reactive edges of the WS2 crystals in the second layer. Such a process proceeds slowly with only up to 40% surface coverage of the second WS2 layer after 150 min of CVD reaction. The CVD reaction is mediated by the starting surface: WF6 precursor preferentially adsorbs on Al2O3, whereas adsorption is not observed on SiO2. Nevertheless, WS2 grows on SiO2 in close proximity to Al2O3 in 90 nm pitch Al2O3/SiO2 line patterns. Hence, functionalization of the starting surface (e.g., SiO2 with Al2O3) can provide opportunities to grow monolayer-thin WS2 crystals at predetermined locations by selective, lateral growth with tunable crystal size, even at low deposition temperatures.

8.
Nature ; 472(7342): 205-8, 2011 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-21451521

RESUMEN

Ferromagnetic or antiferromagnetic spin ordering is governed by the exchange interaction, the strongest force in magnetism. Understanding spin dynamics in magnetic materials is an issue of crucial importance for progress in information processing and recording technology. Usually the dynamics are studied by observing the collective response of exchange-coupled spins, that is, spin resonances, after an external perturbation by a pulse of magnetic field, current or light. The periods of the corresponding resonances range from one nanosecond for ferromagnets down to one picosecond for antiferromagnets. However, virtually nothing is known about the behaviour of spins in a magnetic material after being excited on a timescale faster than that corresponding to the exchange interaction (10-100 fs), that is, in a non-adiabatic way. Here we use the element-specific technique X-ray magnetic circular dichroism to study spin reversal in GdFeCo that is optically excited on a timescale pertinent to the characteristic time of the exchange interaction between Gd and Fe spins. We unexpectedly find that the ultrafast spin reversal in this material, where spins are coupled antiferromagnetically, occurs by way of a transient ferromagnetic-like state. Following the optical excitation, the net magnetizations of the Gd and Fe sublattices rapidly collapse, switch their direction and rebuild their net magnetic moments at substantially different timescales; the net magnetic moment of the Gd sublattice is found to reverse within 1.5 picoseconds, which is substantially slower than the Fe reversal time of 300 femtoseconds. Consequently, a transient state characterized by a temporary parallel alignment of the net Gd and Fe moments emerges, despite their ground-state antiferromagnetic coupling. These surprising observations, supported by atomistic simulations, provide a concept for the possibility of manipulating magnetic order on the timescale of the exchange interaction.

9.
J Chem Phys ; 146(5): 052810, 2017 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-28178804

RESUMEN

Two-dimensional (2D) semiconducting transition metal dichalcogenides (TMDs) are of great interest for applications in nano-electronic devices. Their incorporation requires the deposition of nm-thin and continuous high-k dielectric layers on the 2D TMDs. Atomic layer deposition (ALD) of high-k dielectric layers is well established on Si surfaces: the importance of a high nucleation density for rapid layer closure is well known and the nucleation mechanisms have been thoroughly investigated. In contrast, the nucleation of ALD on 2D TMD surfaces is less well understood and a quantitative analysis of the deposition process is lacking. Therefore, in this work, we investigate the growth of Al2O3 (using Al(CH3)3/H2O ALD) on MoS2 whereby we attempt to provide a complete insight into the use of several complementary characterization techniques, including X-ray photo-electron spectroscopy, elastic recoil detection analysis, scanning electron microscopy, and time-of-flight secondary ion mass spectrometry. To reveal the inherent reactivity of MoS2, we exclude the impact of surface contamination from a transfer process by direct Al2O3 deposition on synthetic MoS2 layers obtained by a high temperature sulfurization process. It is shown that Al2O3 ALD on the MoS2 surface is strongly inhibited at temperatures between 125°C and 300°C, with no growth occurring on MoS2 crystal basal planes and selective nucleation only at line defects or grain boundaries at MoS2 top surface. During further deposition, the as-formed Al2O3 nano-ribbons grow in both vertical and lateral directions. Eventually, a continuous Al2O3 film is obtained by lateral growth over the MoS2 crystal basal plane, with the point of layer closure determined by the grain size at the MoS2 top surface and the lateral growth rate. The created Al2O3/MoS2 interface consists mainly of van der Waals interactions. The nucleation is improved by contributions of reversible adsorption on the MoS2 basal planes by using low deposition temperature in combination with short purge times. While this results in a more two-dimensional growth, additional H and C impurities are incorporated in the Al2O3 layers. To conclude, our growth study reveals that the inherent reactivity of the MoS2 basal plane for ALD is extremely low, and this confirms the need for functionalization methods of the TMD surface to enable ALD nucleation.

10.
Liver Int ; 35(12): 2514-21, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26121926

RESUMEN

BACKGROUND & AIMS: It is well known that inflammation increases liver stiffness (LS) in patients with chronic hepatitis C (HCV) and alcoholic liver disease (ALD) independent of fibrosis stage, but no inflammation-adapted cut-off values have been settled so far. An early identification of rapid fibrosers, however, is essential to decide whom to treat first with the novel but expensive antiviral drugs. METHODS: Liver stiffness, biopsy-proven fibrosis stages F0-F4 (METAVIR or Kleiner score) and routine laboratory parameters were studied in 2068 patients with HCV (n = 1391) and ALD (n = 677). RESULTS: Among the routine parameters for liver damage, AST correlated best with LS (HCV: r = 0.54, P < 0.0001 and ALD: r = 0.34, P < 0.0001). In the absence of elevated transaminases, cut-off values were almost identical between HCV and ALD for F1-2, F3 and F4 (HCV: 5.1, 9.0 and 11.9 kPa vs ALD: 4.9, 8.1 and 10.5 kPa). These cut-off values increased exponentially as a function of median AST level. The impact of AST on LS was higher in lobular-pronounced ALD as compared to portal tract-localized HCV. Most notably, Cohen's weighted Kappa displayed an improved agreement of the novel AST-dependent cut-off values with histological fibrosis stage both for HCV (0.68 vs 0.65) and ALD (0.80 vs 0.76). CONCLUSIONS: The novel AST-adapted cut-off values improve non-invasive fibrosis staging in HCV and ALD and may be also applied to other liver diseases. Especially in HCV, they could help to decide whom to treat first with the novel but expensive antiviral drugs.


Asunto(s)
Aspartato Aminotransferasas/análisis , Hepatitis C Crónica , Inflamación , Cirrosis Hepática , Hepatopatías Alcohólicas , Hígado , Adulto , Biopsia/métodos , Progresión de la Enfermedad , Diagnóstico por Imagen de Elasticidad/métodos , Femenino , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/diagnóstico , Hepatitis C Crónica/fisiopatología , Humanos , Inflamación/patología , Inflamación/fisiopatología , Hígado/patología , Hígado/fisiopatología , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/etiología , Hepatopatías Alcohólicas/complicaciones , Hepatopatías Alcohólicas/diagnóstico , Hepatopatías Alcohólicas/fisiopatología , Masculino , Persona de Mediana Edad , Gravedad del Paciente , Pronóstico , Reproducibilidad de los Resultados
11.
Acta Cardiol ; 70(3): 323-31, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26226706

RESUMEN

Heart failure is a disease affecting millions of patients each year, and is responsible for burdening the world with high mortality rates. More concerns come from its numerous hospital readmissions (with an estimated number of 2.6 million per year which makes it one of the leading diseases responsible for national healthcare expenditures). Despite drastic improvement of therapies in recent years, heart failure remains a progressive disease. Thus, more attention has been given to finding potential biomarkers involved in the pathological mechanisms of this disease that would potentially lead to faster diagnosis and improved prognosis. One of the emerging biomarkers that has just recently come into the spotlight is galectin-3. It was associated in recent clinical trials with both the progression and severity of heart failure. Ventricular remodelling and myocardial fibrosis are essential for heart failure development and are linked to poor outcomes. An ever-growing body of evidence places galectin-3 as an important link between inflammation and fibrosis, which play a prominent role in cardiac remodelling.This review sums up the most relevant experimental and clinical studies about galectin-3 and its potential prognostic value in heart failure. The article also provides a better understanding of this molecule's involvement in heart failure pathology by modulating cardiac fibrosis. It also weighs whether the available data on galectin-3 are consistent enough to reduce readmissions and mortality while improving diagnosis and future therapies for heart failure, versus the possibility that it is simply"another brick in the wall?"


Asunto(s)
Biomarcadores/análisis , Galectina 3/análisis , Insuficiencia Cardíaca/diagnóstico , Remodelación Atrial/fisiología , Galectina 3/fisiología , Humanos , Fallo Renal Crónico/complicaciones , Factores de Riesgo , Volumen Sistólico
12.
Nat Mater ; 12(4): 293-8, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23503010

RESUMEN

Ultrafast laser techniques have revealed extraordinary spin dynamics in magnetic materials that equilibrium descriptions of magnetism cannot explain. Particularly important for future applications is understanding non-equilibrium spin dynamics following laser excitation on the nanoscale, yet the limited spatial resolution of optical laser techniques has impeded such nanoscale studies. Here we present ultrafast diffraction experiments with an X-ray laser that probes the nanoscale spin dynamics following optical laser excitation in the ferrimagnetic alloy GdFeCo, which exhibits macroscopic all-optical switching. Our study reveals that GdFeCo displays nanoscale chemical and magnetic inhomogeneities that affect the spin dynamics. In particular, we observe Gd spin reversal in Gd-rich nanoregions within the first picosecond driven by the non-local transfer of angular momentum from larger adjacent Fe-rich nanoregions. These results suggest that a magnetic material's microstructure can be engineered to control transient laser-excited spins, potentially allowing faster (~ 1 ps) spin reversal than in present technologies.

13.
Chirurgia (Bucur) ; 109(4): 480-5, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25149610

RESUMEN

OBJECTIVE: Surgery remains the best curative option for oesophageal cancer. This demanding intervention performed on a high risk patient is accompanied by high morbidity and mortality rates. The aim of this study was to analyse the preoperative risk assessment using different comorbidity models inpatients operated for esophageal cancer in a tertiary unit. METHODS: A retrospective study was conducted on aprospectively collected database. The performance of several prognostic scores (POSSUM, P-POSSUM, O-POSSUM, Charlson and age adjusted Charlson, ASA score) was assessed in terms of early postoperative outcomes. RESULTS: Out of 137 patients diagnosed with oesophageal cancer, esophagectomy was performed in 43 cases.Postoperative mortality (11.62%) was best predicted by POSSUM score (10.48; 95% CI 9.37 -11.66). The observed morbidity was 58.13%, higher than that expected by POSSUM (48.24%; 95%CI, 44.82-51.66) with a morbidity ratio O E of 1.2. The area under the ROC curve for the physiological score of POSSUM and age adjusted Charlson index showed a good discriminatory power. The best performance was obtained for POSSUM equation, who showed to have the highest area under the ROC curve (0.826; 95%CI, 0.67-0.92). CONCLUSIONS: A thoroughly assessment of comorbidities and the surgeon's clinical assessment remain the best tool for patient selection for surgery.


Asunto(s)
Neoplasias Esofágicas/cirugía , Esofagectomía , Cuidados Posoperatorios , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/mortalidad , Esofagectomía/métodos , Esofagectomía/mortalidad , Femenino , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios , Pronóstico , Curva ROC , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
14.
J Neurosci ; 32(2): 528-41, 2012 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-22238088

RESUMEN

Cone photoreceptors are the primary initiator of visual transduction in the human retina. Dysfunction or death of rod photoreceptors precedes cone loss in many retinal and macular degenerative diseases, suggesting a rod-dependent trophic support for cone survival. Rod differentiation and homeostasis are dependent on the basic motif leucine zipper transcription factor neural retina leucine zipper (NRL). The loss of Nrl (Nrl(-/-)) in mice results in a retina with predominantly S-opsin-containing cones that exhibit molecular and functional characteristics of wild-type cones. Here, we report that Nrl(-/-) retina undergoes a rapid but transient period of degeneration in early adulthood, with cone apoptosis, retinal detachment, alterations in retinal vessel structure, and activation and translocation of retinal microglia. However, cone degeneration stabilizes by 4 months of age, resulting in a thinner but intact outer nuclear layer with residual cones expressing S- and M-opsins and a preserved photopic electroretinogram. At this stage, microglia translocate back to the inner retina and reacquire a quiescent morphology. Gene profiling analysis during the period of transient degeneration reveals misregulation of genes related to stress response and inflammation, implying their involvement in cone death. The Nrl(-/-) mouse illustrates the long-term viability of cones in the absence of rods and retinal pigment epithelium defects in a rodless retina. We propose that Nrl(-/-) retina may serve as a model for elucidating mechanisms of cone homeostasis and degeneration that would be relevant to understanding diseases of the cone-dominant human macula.


Asunto(s)
Apoptosis/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Proteínas del Ojo/genética , Retina/anomalías , Retina/metabolismo , Células Fotorreceptoras Retinianas Conos/metabolismo , Degeneración Retiniana/fisiopatología , Animales , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/deficiencia , Modelos Animales de Enfermedad , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células Fotorreceptoras Retinianas Conos/patología , Degeneración Retiniana/genética , Degeneración Retiniana/patología , Desprendimiento de Retina/genética , Desprendimiento de Retina/patología , Desprendimiento de Retina/fisiopatología
15.
Dev Biol ; 362(2): 219-29, 2012 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-22173065

RESUMEN

Notch signaling is essential for proper lens development, however the specific requirements of individual Notch receptors have not been investigated. Here we report the lens phenotypes of Notch2 conditionally mutant mice, which exhibited severe microphthalmia, reduced pupillary openings, disrupted fiber cell morphology, eventual loss of the anterior epithelium, fiber cell dysgenesis, denucleation defects, and cataracts. Notch2 mutants also had persistent lens stalks as early as E11.5, and aberrant DNA synthesis in the fiber cell compartment by E14.5. Gene expression analyses showed that upon loss of Notch2, there were elevated levels of the cell cycle regulators Cdkn1a (p21Cip1), Ccnd2 (CyclinD2), and Trp63 (p63) that negatively regulates Wnt signaling, plus down-regulation of Cdh1 (E-Cadherin). Removal of Notch2 also resulted in an increased proportion of fiber cells, as was found in Rbpj and Jag1 conditional mutant lenses. However, Notch2 is not required for AEL proliferation, suggesting that a different receptor regulates this process. We found that Notch2 normally blocks lens progenitor cell death. Overall, we conclude that Notch2-mediated signaling regulates lens morphogenesis, apoptosis, cell cycle withdrawal, and secondary fiber cell differentiation.


Asunto(s)
Apoptosis/genética , Diferenciación Celular/genética , Regulación del Desarrollo de la Expresión Génica/fisiología , Cristalino/embriología , Morfogénesis/fisiología , Receptor Notch2/metabolismo , Transducción de Señal/fisiología , Animales , Ciclo Celular/fisiología , Cartilla de ADN/genética , Citometría de Flujo , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica/genética , Hibridación in Situ , Cristalino/metabolismo , Cristalino/ultraestructura , Ratones , Microscopía Electrónica de Transmisión , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena en Tiempo Real de la Polimerasa
16.
Eur J Immunol ; 42(4): 1016-29, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22531925

RESUMEN

Antigen affinity is commonly viewed as the driving force behind the selection for dominant clonotypes that can occur during the T-cell-dependent processes of class switch recombination (CSR) and immune maturation. To test this view, we analyzed the variable gene repertoires of natural monoclonal antibodies to the hapten 2-phenyloxazolone (phOx) as well as those generated after phOx protein carrier-induced thymus-dependent or Ficoll-induced thymus-independent antigen stimulation. In contrast to expectations, the extent of IgM heterogeneity proved similar and many IgM from these three populations exhibited similar or even greater affinities than the classic Ox1 clonotype that dominates only after CSR among primary and memory IgG. The population of clones that were selected during CSR exhibited a reduced VH/VL repertoire that was enriched for variable domains with shorter and more uniform CDR-H3 lengths and almost completely stripped of variable domains encoded by the large VH1 family. Thus, contrary to the current paradigm, T-cell-dependent clonal selection during CSR appeared to select for VH family and CDR-H3 loop content even when the affinity provided by alternative clones exhibited similar to increased affinity for antigen.


Asunto(s)
Anticuerpos Monoclonales de Origen Murino/inmunología , Cambio de Clase de Inmunoglobulina/inmunología , Receptores de Antígenos de Linfocitos B/inmunología , Linfocitos T/inmunología , Animales , Anticuerpos Monoclonales de Origen Murino/genética , Regiones Determinantes de Complementariedad/genética , Regiones Determinantes de Complementariedad/inmunología , Femenino , Haptenos/inmunología , Haptenos/farmacología , Cambio de Clase de Inmunoglobulina/efectos de los fármacos , Cambio de Clase de Inmunoglobulina/genética , Inmunoglobulina G/genética , Inmunoglobulina G/inmunología , Inmunoglobulina M/genética , Inmunoglobulina M/inmunología , Memoria Inmunológica/efectos de los fármacos , Memoria Inmunológica/genética , Memoria Inmunológica/inmunología , Ratones , Ratones Endogámicos BALB C , Receptores de Orexina , Oxazoles/inmunología , Oxazoles/farmacología , Receptores de Antígenos de Linfocitos B/genética , Receptores de Neuropéptido/genética , Receptores de Neuropéptido/inmunología
17.
J Nanosci Nanotechnol ; 13(7): 5203-8, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23901553

RESUMEN

The synthesis of IrQ(ppy)2-5Cl has the advantage of a dual phosphorescence (green and red) which comes from the two ligands, phenylpyridine and quinoline. Their spectroscopic properties evidences the absorption range between 350 nm to 700 nm which is composed from the singlet and triplet states, as a result of hybridizations between Ir and the two ligands, the first one being at 625 nm. The first low energy state comes from the quinoline ligand and is responsible for the red phosphorescence at 660 nm, as results from the Density Functional Theory (DFT) analysis. The hybridization between Ir 5d orbitals and pi ligand orbitals shows strong metallic character with phenylpyridine orbitals (66% and 43%) and weak metallic character with quinoline ligand (16.8%). This fact suggests weak phosphorescence intensity in the emission spectra. Population analysis of each metallic orbital shows a small charge delocalization on the quinoline ligand for the first molecular orbital and a strong delocalization on the phenylpyridine ligands. Solvation effects induce a tuning process for the phosphorescence by changing of the matrix of the organometallic compounds which can be adjusted by the strength of intermolecular dipole-dipole interactions, using a doped guest-host molecular organic thin film system.


Asunto(s)
Mediciones Luminiscentes/métodos , Modelos Químicos , Nanopartículas/química , Compuestos Orgánicos/química , Simulación por Computador , Transporte de Electrón , Electricidad Estática
18.
Balkan J Med Genet ; 16(1): 55-62, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24265585

RESUMEN

Torque teno viruses (TTVs) are recently discovered DNA viruses, with heterogeneous genomes, highly prevalent in populations worldwide. The species that infect humans are Torque teno virus (TTV), Torque teno midi virus (TTMDV) and Torque teno mini virus (TTMV). High-resolution melting analysis (HRMA) is a sensitive and effective method for genotyping and mutation scanning. Up to now, HRMA has not been utilized for detection of TTVs. The aim of this study was to asses if HRMA is suitable for detecting TTVs variants. DNA was extracted from the blood and saliva of 13 healthy subjects for method optimization. Additionally, saliva samples from 100 healthy individuals were collected for estimating the TTVs' prevalence. Viral DNA was amplified by heminested polymerase chain reaction (PCR). Second round amplicons were used for the HRMA. The samples were analyzed using two fluorescent dyes, SYBR (®) Green I and EvaGreen®. The prevalence values for TTV, TTMDV and TTMV were 71.0, 31.0 and 54.0%, respectively. The three major melting curve patterns corresponding to TTV, TTMDV and TTMV on HRMA can be easily distinguished regardless of kit used. Our results showed that HRMA is a rapid and efficient method of detecting human TTVs.

19.
Chirurgia (Bucur) ; 108(4): 468-72, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23958087

RESUMEN

BACKGROUND: The distribution of BRCA mutations varies significantly between populations. The spectrum of BRCA1 and BRCA2 mutations in breast cancers in the Romanian population is incompletely known. The aim of the present study is to investigate the presence of nine BRCA mutations in patients with breast cancer identified in a surgical clinic from Bucharest. METHODS: Unrelated women diagnosed with breast cancer from Coltea Hospital (n=114) and healthy controls (n = 150) were selected for this study. Seven mutations in BRCA1 (185delAG, 5382insC, 943ins10, E1250X, 1294del40, E1373X, R1443X) and two in BRCA2 (IVS16-2A4G and 6174delT) were tested using PCR based protocols. In addition, the presence of BRCA1 185delAG, BRCA1 5382insC, BRCA2 6174delT mutations were tested with a post amplification mutation detection system, based on the ELISA method. RESULTS: Two patients with sporadic breast cancer (2%) and one patient with family history of the disease (7.14%) have the BRCA1 5382insC mutation. No other mutation was detected in patient and control groups. The mutations were not present in the control lot. CONCLUSIONS: Our results indicate that BRCA1 5382insC is a common mutation in Romanian women with breast cancer (3 114).


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Genes BRCA1 , Genes BRCA2 , Mutación , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/epidemiología , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Femenino , Eliminación de Gen , Predisposición Genética a la Enfermedad , Genotipo , Hospitales Universitarios , Humanos , Pacientes Internos/estadística & datos numéricos , Persona de Mediana Edad , Mutagénesis Insercional , Mutación Puntual , Reacción en Cadena de la Polimerasa , Prevalencia , Rumanía/epidemiología
20.
Healthcare (Basel) ; 11(8)2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37108017

RESUMEN

Three years since the COVID-19 pandemic started, there is still little information about patients with chronic medical conditions, such as cardiovascular diseases (CVDs), who become infected with SARS-CoV-2. A retrospective analysis was performed to evaluate the impact of the COVID-19 pandemic on patients with cardiovascular comorbidities hospitalized with positive RT-PCR results for SARS-CoV-2 during the highest peaks of the first three pandemic waves: April 2020, October 2020, and November 2021. The primary outcome was in-hospital mortality; the secondary outcomes were length of hospitalization and required mechanical ventilation to assess the disease severity. Data were extracted from the hospital electronic database system: 680 eligible cases were identified out of 2919 patients. Mortality was the highest in wave 3 (31.9%) compared to the previous waves (13.6% and 25.8%). Hospitalization was also significantly longer in wave 3 (11.58 ± 5.34 vs. 8.94 ± 4.74 and 10.19 ± 5.06; p < 0.001), and so was the need for mechanical ventilation (21.7% vs. 8.2% and 9%; p < 0.001). Older age and male gender were confirmed as highly significant predictors of unfavorable outcomes. Ischemic heart disease worsened the odds of patients' survival irrespective of the three pandemic waves (Breslow-Day test, p = 0.387), with a marginally significant Mantel-Haenszel common estimate for risk: OR = 1.604, 95% (0.996; 2.586). The significantly worse outcomes in wave 3 could have been influenced by a combination of factors: the low percentage of vaccinations in Romanian population, the more virulent delta strain, and pandemic attrition in the care provided to these patients with chronic CVDs.

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