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1.
J Inorg Biochem ; 251: 112433, 2024 02.
Article in English | MEDLINE | ID: mdl-38043136

ABSTRACT

The p53 protein plays a major role in cancer prevention, and over 50% of cancer diagnoses can be attributed to p53 malfunction. p53 incorporates a structural Zn site that is required for proper protein folding and function, and in many cases point mutations can result in loss of the Zn2+ ion, destabilization of the tertiary structure, and eventual amyloid aggregation. Herein, we report a series of compounds designed to act as small molecule stabilizers of mutant p53, and feature Zn-binding fragments to chaperone Zn2+ to the metal depleted site and restore wild-type (WT) function. Many Zn metallochaperones (ZMCs) have been shown to generate intracellular reactive oxygen species (ROS), likely by chelating redox-active metals such as Fe2+/3+ and Cu+/2+ and undergoing associated Fenton chemistry. High levels of ROS can result in off-target effects and general toxicity, and thus, careful tuning of ligand Zn2+ affinity, in comparison to the affinity for other endogenous metals, is important for selective mutant p53 targeting. In this work we show that by using carboxylate donors in place of pyridine we can change the relative Zn2+/Cu2+ binding ability in a series of ligands, and we investigate the impact of donor group changes on metallochaperone activity and overall cytotoxicity in two mutant p53 cancer cell lines (NUGC3 and SKGT2).


Subject(s)
Metallochaperones , Tumor Suppressor Protein p53 , Zinc , Humans , Cell Line, Tumor , Chelating Agents , Metallochaperones/chemistry , Reactive Oxygen Species/metabolism , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Zinc/metabolism , Protein Binding
2.
Exp Biol Med (Maywood) ; 248(23): 2381-2392, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38143435

ABSTRACT

Disturbance of sleep homeostasis encompasses health issues, including metabolic disorders like obesity, diabetes, and augmented stress vulnerability. Sleep and stress interact bidirectionally to influence the central nervous system and metabolism. Murine models demonstrate that decreased sleep time is associated with an increased systemic stress response, characterized by endocrinal imbalance, including the elevated activity of hypothalamic-pituitary-adrenal axis, augmented insulin, and reduced adiponectin, affecting peripheral organs physiology, mainly the white adipose tissue (WAT). Within peripheral organs, a local stress response can also be activated by promoting the formation of corticosterone. This local amplifying glucocorticoid signaling is favored through the activation of the enzyme 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1). In WAT, 11ß-HSD1 activity is upregulated by the sympathetic nervous system, suggesting a link between sleep loss, augmented stress response, and a potential WAT metabolic disturbance. To gain more understanding about this relationship, metabolic and stress responses of WAT-sympathectomized rats were analyzed to identify the contribution of the autonomic nervous system to stress response-related metabolic disorders during chronic sleep restriction. Male Wistar rats under sleep restriction were allowed just 6 h of daily sleep over eight weeks. Results showed that rats under sleep restriction presented higher serum corticosterone, increased adipose tissue 11ß-HSD1 activity, weight loss, decreased visceral fat, augmented adiponectin, lower leptin levels, glucose tolerance impairment, and mildly decreased daily body temperature. In contrast, sympathectomized rats under sleep restriction exhibited decreased stress response (lower serum corticosterone and 11ß-HSD1 activity). In addition, they maintained weight loss, explained by a reduced visceral fat pad, leptin, and adiponectin, improved glucose management, and persisting decline in body temperature. These results suggest autonomic nervous system is partially responsible for the WAT-exacerbated stress response and its metabolic and physiological disturbances.


Subject(s)
Corticosterone , Metabolic Diseases , Male , Mice , Rats , Animals , Corticosterone/metabolism , Leptin/metabolism , Intra-Abdominal Fat/metabolism , Adiponectin/metabolism , 11-beta-Hydroxysteroid Dehydrogenase Type 1/metabolism , Hypothalamo-Hypophyseal System/metabolism , Rats, Wistar , Pituitary-Adrenal System/metabolism , Adipose Tissue/metabolism , Weight Loss , Sleep , Metabolic Diseases/metabolism , Sympathectomy , Glucose/metabolism
3.
Endeavour ; 47(3): 100884, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37806077

ABSTRACT

In 1936 the Austrian geologist Paul Waitz published a seminal bibliographical, historical essay on Colima volcano, Mexico. His article exemplifies well the paths by which geology became what Lorraine Daston has termed sciences of the archive, that is, the manner in which scientific disciplines became concerned with archival work. Waitz's historical description of studies of Colima volcano built a genealogy of observations, ultimately constructing a history of the volcano itself. By bringing attention not only to Waitz's discourse but also to his treatment of visual objects, such as pictorial and photographic landscapes, my article points out how long-term aesthetics, such as the picturesque and the sublime, functioned as tropes which enabled a standardized perception, essential to visualize a clear history of scientific observations, from the landscape paintings of the nineteenth-century artist Johann Moritz Rugendas to Waitz's own photographs.


Subject(s)
Geology , Inventions , Archives , Mexico , Photography
4.
Interv Neuroradiol ; : 15910199231174576, 2023 May 15.
Article in English | MEDLINE | ID: mdl-37186768

ABSTRACT

INTRODUCTION: Intracranial aneurysms (IA) are a focal dilatation of the vessel wall, the rupture of these, causes subarachnoid hemorrhage. Until now, endovascular management is the ideal treatment, providing the interventionist a range of options among which the stent and coils embolization stands out because of its occlusion rate. This study presents the results of a retrospective cohort comparing the effectiveness, morbidity, and mortality of IA treatment with laser-cut stent-assisted coils versus braided stents. METHODOLOGY: Retrospective cohort of patients diagnosed with unruptured intracranial aneurysms treated with coil-assisted laser-cut stents or braided stents between January 2014 and December 2021. RESULTS: In total, 138 patients with 147 intracranial aneurysms were analyzed, 91 of them were treated with laser-cut stent and 56 with braided stents. The main antecedent was arterial hypertension (48.55%). In the immediate angiographic control, a Raymond Roy scale (RRO) I was obtained in 86.81% of the patients with laser-cut stents and 87.50% of the patients with braided stents. In the angiographic follow-up at 12 months, an RRO I occlusion rate of 85.19% was reported in both groups. Perioperative complications occur in 16 patients treated with laser-cut stents and 12 patients treated with braided stents. Three patients presented bleeding complications during the 12-month follow-up, of which two correspond to patients treated with braided stents and one with a laser-cut stent. CONCLUSION: Treatment of patients with intracranial aneurysms with laser-cut stents or braided stents and coils is just as safe and effective.

5.
Curr Opin Chem Biol ; 72: 102230, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36436275

ABSTRACT

The p53 protein plays a critical role in the prevention of genome mutations in the body, however, this protein is frequently mutated in cancer and almost all cancers exhibit malfunction along the p53 pathway. In addition to a loss of activity, mutant p53 protein is prone to unfolding and aggregation, eventually forming amyloid aggregates. There continues to be a considerable effort to develop strategies to restore normal p53 expression and activity and this review details recent advances in small-molecule stabilization of mutant p53 protein and the design of p53 aggregation inhibitors.


Subject(s)
Neoplasms , Tumor Suppressor Protein p53 , Humans , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Protein Aggregates , Neoplasms/metabolism , Mutation , Amyloid
6.
Front Neurosci ; 16: 907508, 2022.
Article in English | MEDLINE | ID: mdl-35937866

ABSTRACT

Epidemiological and experimental evidence recognize a relationship between sleep-wake cycles and adiposity levels, but the mechanisms that link both are not entirely understood. Adipose tissue secretes adiponectin and leptin hormones, mainly involved as indicators of adiposity levels and recently associated to sleep. To understand how two of the main adipose tissue hormones could influence sleep-wake regulation, we evaluated in male rats, the effect of direct administration of adiponectin or leptin in the ventrolateral preoptic nuclei (VLPO), a major area for sleep promotion. The presence of adiponectin (AdipoR1 and AdipoR2) and leptin receptors in VLPO were confirmed by immunohistochemistry. Adiponectin administration increased wakefulness during the rest phase, reduced delta power, and activated wake-promoting neurons, such as the locus coeruleus (LC), tuberomammillary nucleus (TMN) and hypocretin/orexin neurons (OX) within the lateral hypothalamus (LH) and perifornical area (PeF). Conversely, leptin promoted REM and NREM sleep, including increase of delta power during NREM sleep, and induced c-Fos expression in VLPO and melanin concentrating hormone expressing neurons (MCH). In addition, a reduction in wake-promoting neurons activity was found in the TMN, lateral hypothalamus (LH) and perifornical area (PeF), including in the OX neurons. Moreover, leptin administration reduced tyrosine hydroxylase (TH) immunoreactivity in the LC. Our data suggest that adiponectin and leptin act as hormonal mediators between the status of body energy and the regulation of the sleep-wake cycle.

7.
Sensors (Basel) ; 22(13)2022 Jun 30.
Article in English | MEDLINE | ID: mdl-35808467

ABSTRACT

The classification of surface myoelectric signals (sEMG) remains a great challenge when focused on its implementation in an electromechanical hand prosthesis, due to its nonlinear and stochastic nature, as well as the great difference between models applied offline and online. In this work, the selection of the set of the features that allowed us to obtain the best results for the classification of this type of signals is presented. In order to compare the results obtained, the Nina PRO DB2 and DB3 databases were used, which contain information on 50 different movements of 40 healthy subjects and 11 amputated subjects, respectively. The sEMG of each subject was acquired through 12 channels in a bipolar configuration. To carry out the classification, a convolutional neural network (CNN) was used and a comparison of four sets of features extracted in the time domain was made, three of which have shown good performance in previous works and one more that was used for the first time to train this type of network. Set one is composed of six features in the time domain (TD1), Set two has 10 features also in the time domain (TD2) including the autoregression model (AR), the third set has two features in the time domain derived from spectral moments (TD-PSD1), and finally, a set of five features also has information on the power spectrum of the signal obtained in the time domain (TD-PSD2). The selected features in each set were organized in four different ways for the formation of the training images. The results obtained show that the set of features TD-PSD2 obtained the best performance for all cases. With the set of features and the formation of images proposed, an increase in the accuracies of the models of 8.16% and 8.56% was obtained for the DB2 and DB3 databases, respectively, compared to the current state of the art that has used these databases.


Subject(s)
Amputees , Gestures , Algorithms , Electromyography/methods , Hand , Humans , Movement , Neural Networks, Computer
8.
Clin Drug Investig ; 42(6): 491-500, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35604530

ABSTRACT

BACKGROUND AND OBJECTIVES: Durvalumab and atezolizumab are approved as first-line therapy in extensive-stage small-cell lung cancer. Although cost-effectiveness analyses compared these immunotherapy drugs with standard chemotherapy-alone regimens, no head-to-head cost-effectiveness comparisons for these treatments exist. The aim of the present analysis is to determine the cost-effectiveness of durvalumab and atezolizumab as first-line therapy for extensive-stage small-cell lung cancer from the US payers' perspective. METHODS: This study is based on two placebo-controlled, phase 3 clinical trials: CASPIAN and IMpower133. A Markov model was developed to simulate the three health states: progression-free survival, progressed disease, and death in patients with extensive-stage small-cell lung cancer. Transition probabilities were estimated from the clinical trial survival curves and extended with life-time modelling. Health utilities and direct costs of adverse event treatment were included. Main outcome was the incremental cost-effectiveness ratio (ICER) using quality-adjusted life-years saved (QALYS). Sensitivity analysis was performed to assess the impact of variables on the ICER. RESULTS: Durvalumab group has a cost of $187,503 with an effectiveness of 1.08 while atezolizumab has a cost of $160,219 and an effectiveness of 0.932. Durvalumab is not cost-effective compared to atezolizumab with an ICER of $165,182 QALYS, which is over the willingness-to-pay threshold of $150,000. The model was most sensitive to durvalumab cost and the cost of treating durvalumab adverse effects. CONCLUSIONS: With the ICER of durvalumab treatment group being very close to $150,000, setting a higher willingness-to-pay threshold or decreasing the drug cost through contract pricing can increase the cost-effectiveness of durvalumab compared to atezolizumab.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Antibodies, Monoclonal , Antibodies, Monoclonal, Humanized , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Cost-Benefit Analysis , Humans , Lung Neoplasms/drug therapy , Quality-Adjusted Life Years , United States
9.
Chronobiol Int ; 39(3): 374-385, 2022 03.
Article in English | MEDLINE | ID: mdl-34906015

ABSTRACT

Temporal coordination of organisms according to the daytime allows a better performance of physiological processes. However, modern lifestyle habits, such as food intake during the rest phase, promote internal desynchronization and compromise homeostasis and health. The hypothalamic suprachiasmatic nucleus (SCN) synchronizes body physiology and behavior with the environmental light-dark cycle by transmitting time information to several integrative hypothalamic nuclei, such as the paraventricular nucleus (PVN), dorsomedial hypothalamic nucleus (DMH) and median preoptic area (MnPO). The SCN receives metabolic information mainly via Neuropeptide Y (NPY) inputs from the intergeniculate nucleus of the thalamus (IGL). Nowadays, there is no evidence of the response of the PVN, DMH and MnPO when the animals are subjected to internal desynchronization by restricting food access to the rest phase of the day. To explore this issue, we compared the circadian activity of the SCN, PVN, DMH and MnPO. In addition, we analyzed the daily activity of the satiety centers of the brainstem, the nucleus of the tractus solitarius (NTS) and area postrema (AP), which send metabolic information to the SCN, directly or via the thalamic intergeniculate leaflet (IGL). For that, male Wistar rats were assigned to three meal protocols: fed during the rest phase (Day Fed); fed during the active phase (Night Fed); free access to food (ad libitum). After 21 d, the daily activity patterns of these nuclei were analyzed by c-Fos immunohistochemistry, as well as NPY immunohistochemistry, in the SCN. The results show that eating during the rest period produces a phase advance in the activity of the SCN, changes the daily activity pattern in the MnPO, NTS and AP and flattens the c-Fos rhythm in the PVN and DMH. Altogether, these results validate previous observations of circadian dysregulation that occurs within the central nervous system when meals are consumed during the rest phase, a behavior that is involved in the metabolic alterations described in the literature.


Subject(s)
Circadian Rhythm , Hypothalamus , Animals , Male , Rats , Circadian Rhythm/physiology , Hypothalamus/metabolism , Proto-Oncogene Proteins c-fos/metabolism , Rats, Wistar , Suprachiasmatic Nucleus/metabolism
10.
Polymers (Basel) ; 12(12)2020 Nov 27.
Article in English | MEDLINE | ID: mdl-33260898

ABSTRACT

In this work, we present a comparative study of benzoid poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) as electrode and as hole carrier transport layer (HTL) in the manufacture of organic photovoltaic devices using Fischer metal-carbene complexes. The performance of the different devices was evaluated for solar cell applications. Scanning electronic microscopy (SEM) and X-ray diffraction (XRD) were used to characterize the thin films that integrated the devices. A more ordered and crystallized active film microstructure is observed when using benzoid PEDOT:PSS as nucleation layer. The optical gap for both direct and indirect electronic transitions was evaluated from ultraviolet-visible spectroscopy data (UV-vis), as well as the absorption coefficient (α), and the values are in the range of 2.10-2.93 eV. Photovoltaic devices with conventional architecture, using two different chromium carbenes as active layers, were manufactured, and their electrical behavior was studied. The devices were irradiated with different wavelengths between the infrared and ultraviolet regions of the electromagnetic spectrum. Using the PEDOT:PSS film as hole carrier transport layer (HTL) decreases the slope on the ohmic and space charge limited current (SCLC) regions and eliminates the trap-charge limited current (T-CLC) mechanism. Furthermore, a saturation current of ~1.95 × 10-10 A and higher current values ~1.75 × 10-2 A at 4 V, ~4 orders in magnitude larger were observed. The PEDOT:PSS films as HTL in the devices reduced the injection barrier, thus showing a better performance than as anodes in this type of organic solar cells.

11.
Molecules ; 25(24)2020 Dec 09.
Article in English | MEDLINE | ID: mdl-33316924

ABSTRACT

The structure formed by cobalt phthalocyanine (CoPc) and cobalt octaethylporphyrin (CoOEP) with electron-acceptor tetracyano-π-quinodimethane (TCNQ), was studied by Density Functional Theory (DFT) methods. According to theoretical calculations, both cobalt systems can establish dispersion forces related to TCNQ and also in both cases the link between them is built by means of hydrogen bonds. Based on the results of these DFT calculations, we developed experimental work: the organic semiconductors were doped, and the thermal evaporation technique was used to prepare semiconductor thin films of such compounds. The structure of the films was studied by FTIR and Raman spectroscopy. The optical properties of the CoPc-TCNQ and CoOEP-TCNQ films were investigated by means of UV-Vis measurements. The results obtained were used to estimate the type of transitions and the optical bandgap. The results were compared to the previously calculated theoretical bandgap. The CoOEP-TCNQ film presented the smallest theoretical and experimental bandgap. Finally, the electrical properties of the organic semiconductors were evaluated from a PET (polyethylene terephthalate)/indium tin oxide (ITO)/cobalt macrocycle-TCNQ/silver (Ag) device we prepared. The CoOEP-TCNQ-based device showed an ohmic behavior. The device manufactured from CoPc-TCNQ also showed an ohmic behavior at low voltages, but significantly changed to SCLC (space-charge limited conductivity) at high voltage values.


Subject(s)
Indoles/chemistry , Nitriles/chemistry , Organometallic Compounds/chemistry , Porphyrins/chemistry , Semiconductors , Electric Conductivity , Electrochemistry , Models, Molecular , Molecular Structure , Optical Phenomena , Spectroscopy, Fourier Transform Infrared , Spectrum Analysis, Raman , Surface Properties
12.
PLoS One ; 14(11): e0225640, 2019.
Article in English | MEDLINE | ID: mdl-31774858

ABSTRACT

We recently provided highly suggestive preliminary evidence that the renal interstitium contracts reactively in vivo. We demonstrated that renal medullary direct interstitial volume expansion (rmDIVE = 100 µl bolus infusion of 0.9% saline (SS)/30 s) brought about a biphasic renal interstitial hydrostatic pressure (RIHP) response which was abolished when dibutyryl-cAMP was concomitant and interstitially infused. To assess more deeply the feasibility of the concept that the renal interstitium contracts in vivo, two experimental series (S1, S2) were performed in hydropenic rats subjected to acute left renal-denervation, hormonal clamping, and control of renal arterial pressure. In S1, RIHP and renal outer medullary blood flow (RoMBF) were continuously measured before and after a sudden micro-bolus (5µl) injection, into the renal medullary interstitium, of SS containing α-trinositol (α-TNS, anti-inflammatory drug) to either two doses 2 or 4 mM (SS + 2 α-TNS and SS + 4 α-TNS groups). No overall differences between groups in either ΔRIHP or %ΔRoMBF time courses were found; however, in the SS + 2 α-TNS group the data were less scattered and the ΔRIHP time course tended to peak faster and then persisted there, so that, this α-TNS dose was selected for S2. In S2, RIHP and RoMBF were similarly measured in rats randomly assigned to three groups: the CTR group (sham time-control), SS group (SS alone), and SS + α-TNS group. The micro-bolus injection of SS alone (SS group) was unable to increase ΔRIHP. The group with no micro-bolus injection (CTR group) experienced a decrease in ΔRIHP. The micro-bolus injection of SS + 2 α-TNS was accompanied by a differential increase in ΔRIHP (vs. CTR and SS groups). These responses were not associated with differential changes among groups in %ΔRoMBF or hemodilution parameters. These results provide additional evidence that the renal interstitium contracts in vivo.


Subject(s)
Kidney Medulla/physiology , Renal Circulation , Vasoconstriction/physiology , Animals , Hydrostatic Pressure , Kidney Medulla/drug effects , Male , Rats , Rats, Wistar , Sodium Chloride/administration & dosage , Vasoconstriction/drug effects
13.
Molecules ; 23(4)2018 Mar 24.
Article in English | MEDLINE | ID: mdl-29587345

ABSTRACT

A new series of Fischer carbenes have been synthetized and examined as hole-transporting or electron-transporting layers (HTLs or ETLs) in the fabrication of organic solar cells (OSCs). The synthesis of three Fischer aminocarbene complexes with the general formula [Cr(CO)5{C(NHCH2)Ar}] (Ar = 2-pyridyl (3a), 3-pyridyl (3b) and 4-pyridyl (3c)) is reported. The molecular structure of complex 3b has been confirmed by X-ray analysis. In order to study the possible applications of the three Fischer aminocarbenes in OSCs, thin films of these complexes were prepared using a vacuum deposition process. These organometallic films were chemically and morphologically characterized by IR spectroscopy, SEM, AFM and XRD. According to the IR and Tauc analysis, the vacuum deposition process generates thin films free of impurities with an activation energy of 4.0, 2.7 and 2.1 eV for 3a, 3b y 3c, respectively. The UV-vis spectra of the amorphous aminocarbene films show that they are practically transparent to the visible radiation of the electromagnetic spectrum. This is due to the fact that their absorption is located mainly in the ultraviolet range. Two OSCs with bulk-heterojunction configuration were manufactured in order to prove the use of the aminocarbenes as ETL o HTL. The aminocarbene [Cr(CO)5{C(NHCH2) 4-pyridyl}] (3c) proved to be suitable as ETL with a fill factor (FF) of 0.23 and a short circuit current density (JSC) of 1.037 mA/cm².


Subject(s)
Alkynes/chemistry , Dioxolanes/chemistry , Organometallic Compounds/chemical synthesis , Crystallography, X-Ray , Electron Transport , Molecular Structure , Organometallic Compounds/chemistry , Renewable Energy , Solar Energy
14.
Physiol Rep ; 5(12)2017 Jun.
Article in English | MEDLINE | ID: mdl-28646097

ABSTRACT

To learn more about controlling renal interstitial hydrostatic pressure (RIHP), we assessed its response to renal medullary direct interstitial volume expansion (rmDIVE = 100 µL bolus infusion/30 sec). Three experimental series (S) were performed in hydropenic, anesthetized, right-nephrectomized, acute left renal-denervated and renal perfusion pressure-controlled rats randomly assigned to groups in each S. S1: Rats without hormonal clamp were contrasted before and after rmDIVE induced via 0.9% saline solution bolus (SS group) or 2% albumin in SS bolus (2% ALB + SS group). Subcapsular ΔRIHP rose slowly, progressively and similarly in both groups by ~3 mmHg. S2: Rats under hormonal clamp were contrasted before and after sham rmDIVE (time CTR group) and real rmDIVE induced via either SS bolus (SS group) or SS bolus containing the subcutaneous tissue fibroblast relaxant dibutyryl-cAMP (SS + db-cAMP group). ΔRIHP showed time, group, and time*group interaction effects with a biphasic response (early: ~1 mmHg; late: ~4 mmHg) in the SS group that was absent in the SS + db-cAMP group. S3: Two groups of rats (SS and SS + db-cAMP) under hormonal clamp were contrasted as in S2, producing similar ΔRIHP results to those of S2 but showing a slow, progressive, and indistinct decrease in renal outer medullary blood flow in both groups. These results provide highly suggestive preliminary evidence that the renal interstitium is capable of contracting reactively in vivo in response to rmDIVE with SS and demonstrate that such a response is abolished when db-cAMP is interstitially and concomitantly infused.


Subject(s)
Hydrostatic Pressure , Kidney Medulla/physiology , Animals , Bucladesine/pharmacology , Fibroblasts/drug effects , Kidney Medulla/cytology , Kidney Medulla/drug effects , Male , Rats , Rats, Wistar , Sodium Chloride/pharmacology
15.
Front Plant Sci ; 7: 1081, 2016.
Article in English | MEDLINE | ID: mdl-27507978

ABSTRACT

Root hairs are important for nutrient and water uptake and are also critically involved the interaction with soil inhabiting microbiota. Root hairs are tubular-shaped outgrowths that emerge from trichoblasts. This polarized elongation is maintained and regulated by a robust mechanism involving the endomembrane secretory and endocytic system. Members of the syntaxin family of SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) in plants (SYP), have been implicated in regulation of the fusion of vesicles with the target membranes in both exocytic and endocytic pathways. One member of this family, SYP123, is expressed specifically in the root hairs and accumulated in the growing tip region. This study shows evidence of the SYP123 role in polarized trafficking using knockout insertional mutant plants. We were able to observe defects in the deposition of cell wall proline rich protein PRP3 and cell wall polysaccharides. In a complementary strategy, similar results were obtained using a plant expressing a dominant negative soluble version of SYP123 (SP2 fragment) lacking the transmembrane domain. The evidence presented indicates that SYP123 is also regulating PRP3 protein distribution by recycling by endocytosis. We also present evidence that indicates that SYP123 is necessary for the response of roots to plant growth promoting rhizobacterium (PGPR) in order to trigger trigger induced systemic response (ISR). Plants with a defective SYP123 function were unable to mount a systemic acquired resistance in response to bacterial pathogen infection and ISR upon interaction with rhizobacteria. These results indicated that SYP123 was involved in the polarized localization of protein and polysaccharides in growing root hairs and that this activity also contributed to the establishment of effective plant defense responses. Root hairs represent very plastic structures were many biotic and abiotic factors can affect the number, anatomy and physiology of root hairs. Here, we presented evidence that indicates that interactions with soil PGPR could be closely regulated by signaling involving secretory and/or endocytic trafficking at the root hair tip as a quick way to response to changing environmental conditions.

16.
Molecules ; 20(12): 21037-49, 2015 Nov 25.
Article in English | MEDLINE | ID: mdl-26610466

ABSTRACT

Sandwich structures were fabricated by a vacuum deposition method using MPc (M = Cu, Zn), with a Tetrathiafulvalene (TTF) derivative, and Indium Tin Oxide (ITO) and aluminum electrodes. The structure and morphology of the deposited films were studied by IR spectroscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The absorption spectra of TTF derivative-MPc (M = Cu, Zn) thin films deposited at room temperature were recorded in the spectral range 200-1000 nm. The optical band gap of the thin films was determined from the (αhν)(1/2) vs. hν plot. The direct-current (DC) electrical properties of the glass/ITO/TTFderiv-MPc (M = Cu, Zn)/Al structures were also investigated. Changes in conductivity of the derivative-TTF-enriched Pc compounds suggest the formation of alternative paths for carrier conduction. At low voltages, forward current density obeys an ohmic I-V relationship; at higher voltages, conduction is mostly due to a space-charge-limited conduction (SCLC) mechanism.


Subject(s)
Copper/chemistry , Electricity , Heterocyclic Compounds/chemistry , Optical Devices , Zinc/chemistry
17.
Appl Opt ; 53(18): 4033-8, 2014 Jun 20.
Article in English | MEDLINE | ID: mdl-24979437

ABSTRACT

A phase mask represented as the superposition of the four Zernike polynomials associated with primary coma and the trefoil aberrations is presented. The restoration process of the intermediate image is performed by means of the use of the quasi-point source concept. Numerical results of the extended depth of field are presented and compared with other methods of wave front coding applied on a microscope.

18.
Inorg Chem ; 49(9): 4109-16, 2010 May 03.
Article in English | MEDLINE | ID: mdl-20380385

ABSTRACT

New lanthanide complexes with 4,5-bis(diphenyl)phosphoranyl-1,2,3-triazolate (L(-)), LnL(3).nH(2)O (1-8) and LnL(3)(phen).nH(2)O (9-16) (Ln = La, Ce, Nd, Sm, Eu, Gd, Tb, Er), have been prepared and spectroscopically characterized. The structures of LnL(3).nH(2)O (Ln = La, Ce, Nd, Sm and Gd) were determined by X-ray crystallography. The metal centers exhibit a distorted trigonal dodecahedron coordination environment with two symmetrically O,O-bidentate ligands and one unsymmetrically O,N- ligand attached to the metal; two oxygen atoms from neighboring dimethyl sulfoxide (DMSO) molecules complete the coordination sphere. This unsymmetrical ligand coordination behavior was also identified in solution through (31)P{(1)H} NMR studies. Photoluminescence spectroscopy experiments in CH(2)Cl(2) for both types of complexes containing Eu(III) (6, 14) and Tb(III) (7, 15) exhibit strong characteristic red and green emission bands for Eu(III) and Tb(III), respectively. Furthermore, NdL(3) (phen).5H (2)O (11) displays emission in the near-infrared spectral region ((4)F(3/2) --> (4)F(9/2) at 872 nm and (4)F(3/2) --> (4)F(11/2) at 1073 nm). The complexes containing 1,10-phenantroline exhibit higher quantum yields upon excitation at 267 nm, indicating that this auxiliary ligand promotes the luminescence of the complexes; however, luminescence lifetimes (tau) in this case are shorter than those of the LnL(3).nH(2)O series.


Subject(s)
Lanthanoid Series Elements/chemistry , Organometallic Compounds/chemical synthesis , Phenanthrolines/chemistry , Triazoles/chemistry , Crystallography, X-Ray , Ligands , Models, Molecular , Molecular Structure , Organometallic Compounds/chemistry
19.
Arch Clin Neuropsychol ; 22(8): 991-1001, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17900857

ABSTRACT

This study compared the performance of Hispanic American bilingual adults on Spanish and English language versions of a neuropsychological test battery. Language achievement test scores were used to divide 36 bilingual, neurologically intact, Hispanic Americans from south Texas into Spanish-dominant, balanced, and English-dominant bilingual groups. They were administered the eight subtests of the Bateria Neuropsicologica and the Matrix Reasoning subtest of the WAIS-III in Spanish and English. Half the participants were tested in Spanish first. Balanced bilinguals showed no significant differences in test scores between Spanish and English language administrations. Spanish and/or English dominant bilinguals showed significant effects of language of administration on tests with higher language compared to visual perceptual weighting (Woodcock-Munoz Language Survey-Revised, Letter Fluency, Story Memory, and Stroop Color and Word Test). Scores on tests with higher visual-perceptual weighting (Matrix Reasoning, Figure Memory, Wisconsin Card Sorting Test, and Spatial Span), were not significantly affected by language of administration, nor were scores on the Spanish/California Verbal Learning Test, and Digit Span. A problem was encountered in comparing false positive rates in each language, as Spanish norms fell below English norms, resulting in a much higher false positive rate in English across all bilingual groupings. Use of a comparison standard (picture vocabulary score) reduced false positive rates in both languages, but the higher false positive rate in English persisted.


Subject(s)
Cognition/physiology , Hispanic or Latino/psychology , Language , Multilingualism , Neuropsychological Tests/statistics & numerical data , Adult , Aged , Female , Humans , Language Development , Language Tests , Male , Memory , Middle Aged
20.
Rev. Fac. Cienc. Vet ; 35(1/4): 141-55, 1988. ilus
Article in Spanish | LILACS | ID: lil-98905

ABSTRACT

Una muestra de 90 pacientes destinados para la elaboración de jamones tipo Parma se evaluó para pesos, medidas y rendimientos en relación con el proveedor. El análisis estadiístico indicó variabilidad y deferencias significativas en las medidas de grasa en relación al proveedor. El peso del perfil retocado representó 70,36 por ciento del peso inicial, los tejidos blandos separados 23,96 por ciento y el hueso 1,65 por ciento, respectivamente. Las mermas constituyen el 1,82 por ciento del peso inicial. Entre los tejidos blandos separados, la carne representó el 10,75 por cieno, la grasa 11,28 por ciento y la piel 2,51 por ciento, respectivamente. El peso promedio de los perniles frescos y retocados fue: 10,273 ñ 1,217 kg y 7,229 ñ0,832 kg, respectivamente. La mejor ecuación de predicción obtenida (R* X 100 + 86,7), para predecir el peso del jamón retocado fue: 0,797 + 0,658 (peso inicial del pernil fresco) -0,11 (medida de la grasa II)


Subject(s)
Meat , Meat Products , Swine
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