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1.
Clin Kidney J ; 17(1): sfad259, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38186867

RESUMEN

Background: Immunoglobulin A nephropathy (IgAN) is the most frequent recurrent disease in kidney transplant recipients and its recurrence contributes to reducing graft survival. Several variables at the time of recurrence have been associated with a higher risk of graft loss. The presence of clinical or subclinical inflammation has been associated with a higher risk of kidney graft loss, but it is not precisely known how it influences the outcome of patients with recurrent IgAN. Methods: We performed a multicentre retrospective study including kidney transplant recipients with biopsy-proven recurrence of IgAN in which Banff and Oxford classification scores were available. 'Tubulo-interstitial inflammation' (TII) was defined when 't' or 'i' were ≥2. The main endpoint was progression to chronic kidney disease (CKD) stage 5 or to death censored-graft loss (CKD5/DCGL). Results: A total of 119 kidney transplant recipients with IgAN recurrence were included and 23 of them showed TII. Median follow-up was 102.9 months and 39 (32.8%) patients reached CKD5/DCGL. TII related to a higher risk of CKD5/DCGL (3 years 18.0% vs 45.3%, log-rank 7.588, P = .006). After multivariate analysis, TII remained related to the risk of CKD5/DCGL (HR 2.344, 95% CI 1.119-4.910, P = .024) independently of other histologic and clinical variables. Conclusions: In kidney transplant recipients with IgAN recurrence, TII contributes to increasing the risk of CKD5/DCGL independently of previously well-known variables. We suggest adding TII along with the Oxford classification to the clinical variables to identify recurrent IgAN patients at increased risk of graft loss who might benefit from intensified immunosuppression or specific IgAN therapies.

2.
Int J Mol Sci ; 23(20)2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36292994

RESUMEN

In the diatom Phaeodactylum tricornutum, iron limitation promotes a decrease in the content of photosystem II, as determined by measurements of oxygen-evolving activity, thermoluminescence, chlorophyll fluorescence analyses and protein quantification methods. Thermoluminescence experiments also indicate that iron limitation induces subtle changes in the energetics of the recombination reaction between reduced QB and the S2/S3 states of the water-splitting machinery. However, electron transfer from QA to QB, involving non-heme iron, seems not to be significantly inhibited. Moreover, iron deficiency promotes a severe decrease in the content of the extrinsic PsbV/cytochrome c550 subunit of photosystem II, which appears in eukaryotic algae from the red photosynthetic lineage (including diatoms) but is absent in green algae and plants. The decline in the content of cytochrome c550 under iron-limiting conditions is accompanied by a decrease in the binding of this protein to photosystem II, and also of the extrinsic PsbO subunit. We propose that the lack of cytochrome c550, induced by iron deficiency, specifically affects the binding of other extrinsic subunits of photosystem II, as previously described in cyanobacterial PsbV mutants.


Asunto(s)
Diatomeas , Deficiencias de Hierro , Humanos , Complejo de Proteína del Fotosistema II/metabolismo , Diatomeas/metabolismo , Citocromos c/metabolismo , Clorofila/metabolismo , Oxígeno/metabolismo , Hierro/metabolismo , Agua/metabolismo
3.
Psychiatry Res ; 317: 114869, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36240634

RESUMEN

The aim of this work is to investigate the effectiveness of Deep Brain Stimulation (DBS) in patients with severe Obsessive Compulsive Disorder (OCD) who are resistant to pharmacological treatments, focusing on obsessive compulsive, depressive and anxiety symptoms as well as global function. A systematic review and meta-analysis including 25 studies (without language restrictions) from between 2003 and 2020 was performed. A total of 303 patients were evaluated twice (before and after DBS). After DBS treatment OCD patients with resistance to pharmacological treatments showed a significant improvement of obsessive-compulsive symptoms (25 studies; SMD=2.39; 95% CI, 1.91 to 2.87; P<0.0001), depression (9 studies; SMD= 1.19; 95%CI, 0.84 to 1.54; P<0.0001), anxiety (5 studies; SMD=1.00; 95%CI, 0.32 to 1.69; P=0.004) and functionality (7 studies; SMD=-3.51; 95%CI, -5.00 to -2.02; P=0.005) measured by the standardized scales: Yale Brown Obsessive Compulsive Scale (YBOCS), Hamilton Depression Rating Scale (HAM-D), Hamilton Anxiety Rating Scale (HAM-A) and Global Assessment of Function (GAF). Publication bias were discarded by using funnel plot. The main conclusions of this meta-analysis highlight the statistically significant effectiveness of DBS in patients with severe OCD who are resistant to conventional pharmacological treatments, underlying its role in global functioning apart from obsessive-compulsive symptoms.


Asunto(s)
Estimulación Encefálica Profunda , Trastorno Obsesivo Compulsivo , Humanos , Estimulación Encefálica Profunda/métodos , Trastorno Obsesivo Compulsivo/diagnóstico , Ansiedad , Resultado del Tratamiento
4.
Int J Immunopathol Pharmacol ; 36: 3946320221115310, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35981966

RESUMEN

In the diagnostic of systemic sclerosis (SSc), both anti-centromere (ACA) and anti-topoisomerase I (ATA) antibodies are considered mutually exclusive, though their coexistence has been also reported in some patients. Notably, nintedanib has been approved for the treatment of interstitial lung disease associated to SSc. Herein, we present the clinical case of a 41-year-old woman with SSc who shows an immunological seroconversion (from ACA positivity to a coexistence of ACA and ATA antibodies) together with changes in her clinical phenotype. Besides, the patient responds positively to the treatment of her lung involvement with a combination of immunomodulators and antifibrotic agents.


Asunto(s)
Autoanticuerpos , Esclerodermia Sistémica , Femenino , Humanos , Indoles/uso terapéutico , Rituximab/uso terapéutico , Esclerodermia Sistémica/complicaciones , Esclerodermia Sistémica/tratamiento farmacológico
5.
Materials (Basel) ; 14(24)2021 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-34947256

RESUMEN

This paper presents a comparison of six index properties collected during durability inspections of five Mexican seaports. Typical durability indicators such as compressive strength, saturated electrical resistivity, ultrasonic pulse velocity, percent total void content, capillary porosity, and chloride concentration profiles were analyzed to obtain empirical correlations with the non-steady-state chloride diffusion coefficient. These indices were compared to determine correlation coefficients that are the most important for obtaining better corrosion initiation forecasting. Two models of corrosion initiation time (ti) were used: Fick's second law of diffusion and the reported UNE-83994-2 (Spanish Association for Standardization, UNE) in which electrical resistivity was used to calculate concrete service life. The data from both models were cleaned using correlated variables, and the initial variables were compared with ti. The main result achieved was the verification of the feasibility of using correlations of variables to clean unnecessary data in order to calculate ti. Additionally, electrical resistivity was identified as one of the main durability indexes for in-service concrete structures exposed to marine environments. This is important because electrical resistivity is a non-destructive and reliable test that can be measured both in the laboratory and in the field very easily.

7.
Physiol Plant ; 171(2): 277-290, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33247466

RESUMEN

We have investigated if the heterologous expression of a functional green alga plastocyanin in the diatom Phaeodactylum tricornutum can improve photosynthetic activity and cell growth. Previous in vitro assays showed that a single-mutant of the plastocyanin from the green algae Chlamydomonas reinhardtii is effective in reducing P. tricornutum photosystem I. In this study, in vivo assays with P. tricornutum strains expressing this plastocyanin indicate that even the relatively low intracellular concentrations of holo-plastocyanin detected (≈4 µM) are enough to promote an increased growth (up to 60%) under iron-deficient conditions as compared with the WT strain, measured as higher cell densities, content in pigments and active photosystem I, global photosynthetic rates per cell, and even cell volume. In addition, the presence of plastocyanin as an additional photosynthetic electron carrier seems to decrease the over-reduction of the plastoquinone pool. Consequently, it promotes an improvement in the maximum quantum yield of both photosystem II and I, together with a decrease in the acceptor side photoinhibition of photosystem II-also associated to a reduced oxidative stress-a decrease in the peroxidation of membrane lipids in the choroplast, and a lower degree of limitation on the donor side of photosystem I. Thus the heterologous plastocyanin appears to act as a functional electron carrier, alternative to the native cytochrome c6 , under iron-limiting conditions.


Asunto(s)
Diatomeas , Plastocianina , Diatomeas/genética , Diatomeas/metabolismo , Transporte de Electrón , Hierro/metabolismo , Fotosíntesis , Complejo de Proteína del Fotosistema I/metabolismo , Plastocianina/metabolismo
8.
Physiol Plant ; 171(2): 268-276, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33231323

RESUMEN

The afterglow (AG) photosynthetic luminescence is a long-lived chlorophyll fluorescence emitted from PSII after the illumination of photosynthetic materials by FR or white light and placed in darkness. The AG emission corresponds to the fraction of PSII centers in the S2/3 QB non-radiative state immediately after pre-illumination, in which the arrival of an electron transferred from stroma along cyclic/chlororespiratory pathway(s) produces the S2/3 QB - radiative state that emits luminescence. This emission can be optimally recorded by a linear temperature gradient as sharp thermoluminescence (TL) band peaking at about 45°C. The AG emission recorded by TL technique has been proposed as a simple non-invasive tool to investigate the chloroplast energetic state and some of its metabolism processes as cyclic transport of electrons around PSI, chlororespiration or photorespiration. On the other hand, this emission has demonstrated to be a useful probe to study the effect of various stress conditions in photosynthetic materials.


Asunto(s)
Luminiscencia , Complejo de Proteína del Fotosistema II , Clorofila , Transporte de Electrón , Luz , Fotosíntesis , Complejo de Proteína del Fotosistema II/metabolismo , Hojas de la Planta/metabolismo
9.
J Psychosom Res ; 124: 109780, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31443809

RESUMEN

OBJECTIVE: To compare quality of life (QoL), anxiety and depressive symptoms, alcohol consumption and other correlates between patients with psoriasis and controls; and to identify features of psoriasis associated with lower levels of QoL. METHOD: Case-control study including 70 subjects with moderate-severe psoriasis and 140 controls without psoriasis. All participants answered the Short Form Health Survey (SF-36), with physical and mental component scores of quality of life, and the Hospital Anxiety and Depression Scale (HADS). Among subjects with psoriasis, the Psoriasis Area and Severity Index (PASI) and the Dermatology Life Quality Index (DLQI) were used, respectively, to measure the severity of psoriasis and the impact of psoriasis on the specific quality of life. RESULTS: Compared to controls, patients with psoriasis showed higher HADS depression score and alcohol consumption, and lower QoL. Among subjects with psoriasis, multivariate analysis showed: 1) poorer physical QoL was associated with older age, articular lesions and anxious symptoms, whereas poorer mental QoL was associated with younger age, female sex, genital lesions and depressive symptoms; 2) the higher the severity of psoriasis, the lower the level of QoL and the higher the levels of anxious or depressive symptoms; and 3) female sex and articular or genital location of lesions are linked with higher HADS scores. CONCLUSION: Higher scores in anxiety and depression and lower QoL is common in psoriasis, especially among women and those with genital or articular lesions. Dermatologists should give special attention to this subgroup of persons with psoriasis in order to prevent future psychopathology.


Asunto(s)
Ansiedad/complicaciones , Depresión/complicaciones , Psoriasis/psicología , Calidad de Vida , Adulto , Anciano , Consumo de Bebidas Alcohólicas/psicología , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psoriasis/complicaciones , Índice de Severidad de la Enfermedad
10.
Physiol Plant ; 166(1): 240-250, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30628087

RESUMEN

The afterglow (AG) luminescence is a delayed chlorophyll fluorescence emitted by the photosystem II that seems to reflect the level of assimilatory potential (NADPH+ATP) in chloroplast. In this work, the thermoluminescence (TL) emissions corresponding to the AG band were investigated in plants of the WT and the Ljgln2-2 photorespiratory mutant from Lotus japonicus grown under either photorespiratory (air) or non-photorespiratory (high concentration of CO2 ) conditions. TL glow curves obtained after two flashes induced the strongest overall TL emissions, which could be decomposed in two components: B band (tmax = 27-29°C) and AG band (tmax = 44-45°C). Under photorespiratory conditions, WT plants showed a ratio of 1.17 between the intensity of the AG and B bands (IAG /IB ). This ratio increased considerably under non-photorespiratory conditions (2.12). In contrast, mutant Ljgln2-2 plants grown under both conditions showed a high IAG /IB ratio, similar to that of WT plants grown under non-photorespiratory conditions. In addition, high temperature thermoluminescence (HTL) emissions associated to lipid peroxidation were also recorded. WT and Ljgln2-2 mutant plants grown under photorespiratory conditions showed both a significant HTL band, which increased significantly under non-photorespiratory conditions. The results of this work indicate that changes in the amplitude of IAG /IB ratio could be used as an in vivo indicator of alteration in the level of photorespiratory metabolism in L. japonicus chloroplasts. Moreover, the HTL results suggest that photorespiration plays some role in the protection of the chloroplast against lipid peroxidation.


Asunto(s)
Lotus/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Cloroplastos/metabolismo , Transporte de Electrón/fisiología , Luminiscencia , Temperatura
11.
Psychiatry Res ; 272: 182-189, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30583261

RESUMEN

Studies on disordered eating behaviors (DEB) in multicultural populations with multiple religious/cultural affiliations are needed in order to clarify the relationship between cultural background and DEB. Therefore, we compared the presence of DEB among Christian and Muslim adolescents who share their school environment, controlling for the effect of body mass index, demographic variables and lifestyle habits. A sample of 493 girls and boys (339 Christian, 138 Muslim) whose mean (±SD) age was 14.8 (±1.7) years completed self-reporting questionnaires and underwent measurements of anthropometric data. Religious/cultural affiliation was defined by self-identification. The dependent variable, DEB was assessed by means of the Eating Disorders Inventory (EDI-2). Muslim girls and boys score higher than Christians on EDI-2 total scores, especially on the perfectionism subscale. Bivariate and multivariate analyses were used to determine the characteristics associated with DEB, which were detected in 24% of participants (19% of Christians and in 35% of Muslims). Among girls, DEB were directly associated with overweight or obesity, the presence of frequent quarrels with parents, academic failure and spending more than 3 h a day watching screen images. Among boys, DEB were directly associated with overweight or obesity and Muslim background; and inversely associated with age and socioeconomic status.


Asunto(s)
Conducta del Adolescente/etnología , Cristianismo/psicología , Cultura , Trastornos de Alimentación y de la Ingestión de Alimentos/etnología , Islamismo/psicología , Adolescente , Conducta del Adolescente/psicología , Factores de Edad , Antropometría , Índice de Masa Corporal , Conducta Alimentaria/etnología , Conducta Alimentaria/psicología , Trastornos de Alimentación y de la Ingestión de Alimentos/psicología , Femenino , Humanos , Estilo de Vida , Masculino , Obesidad/etnología , Obesidad/psicología , Autoinforme , Factores Sexuales , Clase Social , España
12.
Curr Protein Pept Sci ; 20(4): 368-395, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30387391

RESUMEN

The plasma membrane forms a permeable barrier that separates the cytoplasm from the external environment, defining the physical and chemical limits in each cell in all organisms. The movement of molecules and ions into and out of cells is controlled by the plasma membrane as a critical process for cell stability and survival, maintaining essential differences between the composition of the extracellular fluid and the cytosol. In this process aquaporins (AQPs) figure as important actors, comprising highly conserved membrane proteins that carry water, glycerol and other hydrophilic molecules through biomembranes, including the cell wall and membranes of cytoplasmic organelles. While mammals have 15 types of AQPs described so far (displaying 18 paralogs), a single plant species can present more than 120 isoforms, providing transport of different types of solutes. Such aquaporins may be present in the whole plant or can be associated with different tissues or situations, including biotic and especially abiotic stresses, such as drought, salinity or tolerance to soils rich in heavy metals, for instance. The present review addresses several aspects of plant aquaporins, from their structure, classification, and function, to in silico methodologies for their analysis and identification in transcriptomes and genomes. Aspects of evolution and diversification of AQPs (with a focus on plants) are approached for the first time with the aid of the LCA (Last Common Ancestor) analysis. Finally, the main practical applications involving the use of AQPs are discussed, including patents and future perspectives involving this important protein family.


Asunto(s)
Acuaporinas , Proteínas de Plantas , Plantas/química , Acuaporinas/genética , Acuaporinas/metabolismo , Biotecnología , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
13.
Appl Energy ; 210: 518-528, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-31534297

RESUMEN

Pricing, incentives, and economic penalties (monetization) are common approaches to control and improve water usage and total direct greenhouse gas emissions (externalities) of energy and other industrial systems. We discuss that homogenous pricing for externalities provides limited flexibility for controlling and improving environmental impacts as different systems are affected differently by externalities. We use trade-off analysis and scalarization techniques to determine marginal prices for water and carbon by taking into account the actual physical and technical limits, stakeholders, and real-time conditions of the system at hand. We demonstrate that high water and emission prices might be needed to control and improve the current system of fixed price for externalities. In addition, a combined heat and power (CHP) system providing hot water and electricity to a real residential building complex is undertaken as case study to demonstrate and describe these concepts. For this CHP system, we found that carbon prices should be increased by a factor of 14 and water prices by a factor of 217 to achieve an optimal compromise between cost, water use, and emissions. Our results point towards the need to consider alternative pricing schemes such as resource bidding (as is done with electricity) that better capture technology trade-offs and push systems towards their efficiency limits.

14.
Actas Esp Psiquiatr ; 45(2): 71-78, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28353292

RESUMEN

Human immunodeficiency virus (HIV) infection can cause neuropsychiatric disorders such as cognitive impairment, behavioural difficulties or psychiatric symptoms –for instance, mania and psychosis. HIV patients with psychiatric comorbidities need an appropriate treatment which tackles the HIV infection as much as the particular mental symptoms. Here we present the case of a patient suffering from delusions, which turned out to be caused by encephalitis secondary to a previously unknown HIV infection. A review of psychosis in HIV-infected patients is also presented. This review is focused on the epidemiology, etiopathogenesis and clinical presentation of HIV-induced psychosis, as well as the recommended pharmacological treatment (antiretroviral therapy and antipsychotic medication) and the expected treatment response. We also present wide information concerning pharmacological interactions between antiretroviral and antipsychotic medications that we hope will help the clinician to better manage this complex condition.


Asunto(s)
Infecciones por VIH/complicaciones , Trastornos Psicóticos/tratamiento farmacológico , Trastornos Psicóticos/etiología , Femenino , Humanos , Persona de Mediana Edad
15.
Psychiatry Res ; 250: 264-269, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28183022

RESUMEN

Major Depressive Disorder (MDD) and Nicotine dependence (ND) often co-occur. However, little attention has been given to the temporal order between the two disorders. We compared the sociodemographic and clinical characteristics of individuals whose onset of ND preceded (ND-prior) or followed the onset of MDD (MDD-prior). Binary logistic regression models were computed to compare ND-prior (n=546) and MDD-prior (n=801) individuals from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC, n=43,093). We found that MDD-prior were more likely to have a history of suicide attempts and a family history of both depression and antisocial behavior, to have had psychiatric hospitalization, and to have an earlier age of onset of the first depressive episode; but a later age of onset for both daily smoking and ND. On average, MDD-prior individuals showed a significantly longer transition time from daily smoking to ND (15.6±0.6 vs. 6.9±0.4 years, P<0.001). In contrast, ND-prior subjects had a significantly greater proportion of withdrawal symptoms, and of lifetime alcohol use or alcohol use disorder. We conclude that the phenomenology and course of ND and MDD vary significantly, depending on which disorder had earlier onset.


Asunto(s)
Trastorno Depresivo Mayor/epidemiología , Trastorno Depresivo Mayor/psicología , Encuestas Epidemiológicas/tendencias , Tabaquismo/epidemiología , Tabaquismo/psicología , Adolescente , Adulto , Trastornos Relacionados con Alcohol/epidemiología , Comorbilidad , Trastorno Depresivo Mayor/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos de la Personalidad/diagnóstico , Trastornos de la Personalidad/epidemiología , Trastornos de la Personalidad/psicología , Fumar/psicología , Fumar/tendencias , Intento de Suicidio/psicología , Factores de Tiempo , Tabaquismo/diagnóstico , Estados Unidos/epidemiología , Adulto Joven
16.
Rev Psiquiatr Salud Ment ; 10(1): 45-58, 2017.
Artículo en Inglés, Español | MEDLINE | ID: mdl-27291831

RESUMEN

We systematically review factors associated with the presence of psychological distress or common mental disorders in migrant populations. Articles published between January 2000 and December 2014 were reviewed and 85 applying multivariate statistical analysis were selected. Common mental disorders were significantly associated with socio-demographic and psychological characteristics, as observed in large epidemiological studies on general populations. The probability of common mental disorders occurrence differs significantly among migrant groups according to their region of origin. Moreover, traumatic events prior to migration, forced, unplanned, poorly planned or illegal migration, low level of acculturation, living alone or separated from family in the host country, lack of social support, perceived discrimination, and the length of migrants' residence in the host country all increase the likelihood of CMD. In contrast, language proficiency, family reunification, and perceived social support reduce such probability. Factors related with the risk of psychiatric morbidity among migrants should be taken into account to design preventive strategies.


Asunto(s)
Emigrantes e Inmigrantes/psicología , Trastornos Mentales/etiología , Estrés Psicológico/etiología , Migrantes/psicología , Salud Global , Humanos , Factores de Riesgo
17.
Photosynth Res ; 133(1-3): 273-287, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28032235

RESUMEN

The photosynthetic cytochrome c 550 from the marine diatom Phaeodactylum tricornutum has been purified and characterized. Cytochrome c 550 is mostly obtained from the soluble cell extract in relatively large amounts. In addition, the protein appeared to be truncated in the last hydrophobic residues of the C-terminus, both in the soluble cytochrome c 550 and in the protein extracted from the membrane fraction, as deduced by mass spectrometry analysis and the comparison with the gene sequence. Interestingly, it has been described that the C-terminus of cytochrome c 550 forms a hydrophobic finger involved in the interaction with photosystem II in cyanobacteria. Cytochrome c 550 was almost absent in solubilized photosystem II complex samples, in contrast with the PsbO and Psb31 extrinsic subunits, thus suggesting a lower affinity of cytochrome c 550 for the photosystem II complex. Under iron-limiting conditions the amount of cytochrome c 550 decreases up to about 45% as compared to iron-replete cells, pointing to an iron-regulated synthesis. Oxidized cytochrome c 550 has been characterized using continuous wave EPR and pulse techniques, including HYSCORE, and the obtained results have been interpreted in terms of the electrostatic charge distribution in the surroundings of the heme centre.


Asunto(s)
Grupo Citocromo c/metabolismo , Diatomeas/metabolismo , Fotosíntesis , Secuencia de Aminoácidos , Grupo Citocromo c/química , Grupo Citocromo c/aislamiento & purificación , Espectroscopía de Resonancia por Spin del Electrón , Modelos Moleculares , Peso Molecular , Complejo de Proteína del Fotosistema II/metabolismo , Electricidad Estática
18.
Front Plant Sci ; 7: 1050, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27536301

RESUMEN

Iron limitation is the major factor controlling phytoplankton growth in vast regions of the contemporary oceans. In this study, a combination of thermoluminescence (TL), chlorophyll fluorescence, and P700 absorbance measurements have been used to elucidate the effects of iron deficiency in the photosynthetic electron transport of the marine diatom P. tricornutum. TL was used to determine the effects of iron deficiency on photosystem II (PSII) activity. Excitation of iron-replete P. tricornutum cells with single turn-over flashes induced the appearance of TL glow curves with two components with different peaks of temperature and contributions to the total signal intensity: the B band (23°C, 63%), and the AG band (40°C, 37%). Iron limitation did not significantly alter these bands, but induced a decrease of the total TL signal. Far red excitation did not increase the amount of the AG band in iron-limited cells, as observed for iron-replete cells. The effect of iron deficiency on the photosystem I (PSI) activity was also examined by measuring the changes in P700 redox state during illumination. The electron donation to PSI was substantially reduced in iron-deficient cells. This could be related with the important decline on cytochrome c 6 content observed in these cells. Iron deficiency also induced a marked increase in light sensitivity in P. tricornutum cells. A drastic increase in the level of peroxidation of chloroplast lipids was detected in iron-deficient cells even when grown under standard conditions at low light intensity. Illumination with a light intensity of 300 µE m(-2) s(-1) during different time periods caused a dramatic disappearance in TL signal in cells grown under low iron concentration, this treatment not affecting to the signal in iron-replete cells. The results of this work suggest that iron deficiency induces partial blocking of the electron transfer between PSII and PSI, due to a lower concentration of the electron donor cytochrome c 6. This decreased electron transfer may induce the over-reduction of the plastoquinone pool and consequently the appearance of acceptor side photoinhibition in PSII even at low light intensities. The functionality of chlororespiratory electron transfer pathway under iron restricted conditions is also discussed.

19.
Biochemistry ; 55(15): 2214-26, 2016 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-27026225

RESUMEN

The characteristic features of two types of short-term light adaptations of the photosynthetic apparatus of the cyanobacterium Synechocystis sp. PCC 6803, state transition and blue-green light-induced fluorescence quenching, were compared in wild-type and cytochrome b559 and PsbJ mutant cells with mutations on and near the QC site in photosystem II (PSII). All mutant cells grew photoautotrophically and assembled stable PSII. Thermoluminescence emission experiments showed a decrease in the stability of the S3QB(-)/S2QB(-) charge pairs in the A16FJ, S28Aß, and V32Fß mutant cells. When dark-adapted wild-type and mutant cells were illuminated by medium-intensity blue light, the increase in the PSII fluorescence yield (indicating a transition to state 1) was more prominent in mutant than wild-type cells. Strong blue-light conditions induced a quenching of fluorescence corresponding to nonphotochemical fluorescence quenching (NPQ). The extension of NPQ decreased significantly in the mutants, and the kinetics appeared to be affected. When similar measures were repeated on an orange carotenoid protein (OCP)-deficient background, little or no quenching was observed, which confirms that the decrease in fluorescence under strong blue light corresponded to the OCP-dependent NPQ. Immunoblot results showed that the attenuated effect of blue light-induced NPQ in mutant cells was not due to a lack of OCP. Photosynthetic growth and biomass production were greater for A16FJ, S28Aß, and V32Fß mutant cells than for wild-type cells under normal growth conditions. Our results suggest that mutations of cytochrome b559 and PsbJ on and near the QC site of PSII may modulate the short-term light response in cyanobacteria.


Asunto(s)
Proteínas Bacterianas/genética , Grupo Citocromo b/genética , Complejo de Proteína del Fotosistema II/genética , Synechocystis/crecimiento & desarrollo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Sitios de Unión/genética , Grupo Citocromo b/química , Grupo Citocromo b/metabolismo , Luz , Modelos Moleculares , Mutación , Organismos Modificados Genéticamente , Fotosíntesis/genética , Fotosíntesis/efectos de la radiación , Complejo de Proteína del Fotosistema II/química , Complejo de Proteína del Fotosistema II/metabolismo , Synechocystis/genética , Synechocystis/efectos de la radiación
20.
Actas Esp Psiquiatr ; 44(1): 20-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26905887

RESUMEN

BACKGROUND: Metabolic syndrome (MS) and cardiovascular risk factors (CRF) have been associated with patients with schizophrenia. The main objective is to assess the evolution of CRF and prevalence of MS for 12 months in a cohort of overweight patients diagnosed with schizophrenia schizophreniform disorder or schizoaffective disorder in which the recommendations for the assessment and control of metabolic and cardiovascular risk were applied. METHODS: The Control of Metabolic and Cardiovascular Risk in Patients with Schizophrenia and Overweight (CRESSOB) study is a 12-month, observational, prospective, open-label, multicentre, naturalistic study including 109 community mental health clinics of Spain. The study included a total of 403 patients, of whom we could collect all variables related to CRF and MS in 366 patients. Of these 366 patients, 286 completed the follow-up, (baseline, months 3, 6 and 12) where they underwent a complete physical examination and a blood test (glucose, cholesterol and triglycerides), they were asked about their health-related habits (smoking, diet and exercise) and they were given a series of recommendations to prevent cardiovascular risk and MS. RESULTS: A total of 403 patients were included, 63% men, mean age (mean; (SD)) 40.5 (10.5) years. After 12 months, the study showed statistically significant decrease in weight (p<0.0001), waist circumference (p<0.0001), BMI (p<0.0001), blood glucose (p=0.0034), total cholesterol (p<0.0001), HDL cholesterol (p=0.02), LDL cholesterol (p=0.0023) and triglycerides (p=0.0005). There was a significant reduction in the percentage of smokers (p=0.0057) and in the risk of heart disease at 10 years (p=0.0353). CONCLUSION: Overweight patients with schizophrenia who receive appropriate medical care, including CRF monitoring and control of health-related habits experience improvements with regard to most CRFs.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Consejo , Síndrome Metabólico/prevención & control , Obesidad/terapia , Sobrepeso/terapia , Esquizofrenia/terapia , Adulto , Femenino , Promoción de la Salud , Humanos , Masculino , Persona de Mediana Edad , Obesidad/fisiopatología , Sobrepeso/fisiopatología , Estudios Prospectivos , Factores de Riesgo , Esquizofrenia/fisiopatología , España
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