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1.
Foods ; 12(10)2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37238791

RESUMEN

Research on food loss and waste (FLW) is quite limited in emerging countries, such as Romania, as the phenomenon, its consequences, and implications are not yet properly understood by both policy makers and consumers. Therefore, the aim of this paper is to conduct representative research in Romania to identify the main clusters of consumers depending on their food waste behaviour. By means of cluster analysis, we highlight the main consumer typologies in Romania, regarding their food waste behaviour. The main findings reveal the presence of three distinct segments of consumer typologies based on their food waste behaviour, including low-income young wasters, conscious middle-age wasters, and well-educated mature non-wasters. This study highlights the need for targeted interventions that consider the unique characteristics and behaviours of each segment to effectively reduce FLW at the household level. Overall, this paper provides important insights for academia and for policymakers in the field of FLW management. The food loss and waste behaviour has significant economic, social, and environmental impacts, and reducing it requires a common effort from all stakeholders. Reducing food waste presents challenges, but also presents an opportunity to improve economic, social, and environmental outcomes.

2.
Clujul Med ; 89(1): 169-75, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27004041

RESUMEN

Pannus-related prosthetic valve dysfunction, a complication of mechanical prosthetic valve replacement, is rare, with a slowly progressive evolution, but it can be acute, severe, requiring surgical reintervention. We present the case of a patient with a mechanical single disc aortic prosthesis, with moderate prosthesis-patient mismatch, minor pannus found on previous ultrasound examinations, who presented to our service with angina pain with a duration of 1 hour, subsequently interpreted as non-ST segment elevation myocardial infarction (NSTEMI) syndrome. Coronarography showed normal epicardial coronary arteries, an ample movement of the prosthetic disc, without evidence of coronary thromboembolism, and Gated Single-Photon Emission Computerized Tomography (SPECT) with Technetium (Tc)-99m detected no perfusion defects. Transthoracic echocardiography (TTE) evidenced a dysfunctional prosthesis due to a subvalvular mass; transesophageal echocardiography (TOE) showed the interference of this mass, with a pannus appearance, with the closure of the prosthetic disc. Under conditions of repeated angina episodes, under anticoagulant treatment, surgery was performed, with the intraoperative confirmation of pannus and its removal. Postoperative evolution was favorable. This case reflects the diagnostic and therapeutic management problems of pannus-related prosthetic valve dysfunction.

3.
In Vivo ; 27(6): 695-700, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24292570

RESUMEN

The goal of the present study was to obtain pilot data on the effects of protracted low-dose/low-dose-rate (LDR) γ-rays on the skin, both with and without acute gamma or proton irradiation (IR). Six groups of C57BL/6 mice were examined: a) 0 Gy control, b) LDR, c) Gamma, d) LDR+Gamma, e) Proton, and f) LDR+Proton. LDR radiation was delivered to a total dose of 0.01 Gy (0.03 cGy/h), whereas the Gamma and Proton groups received 2 Gy (0.9 Gy/min and 1.0 Gy/min, respectively). Assays were performed 56 days after exposure. Skin samples from all irradiated groups had activated caspase-3, indicative of apoptosis. The significant (p<0.05) increases in immunoreactivity in the Gamma and Proton groups were not present when LDR pre-exposure was included. However, the terminal deoxynucleotidyl transferase dUTP nick-end labeling assay for DNA fragmentation and histological examination of hematoxylin and eosin-stained sections revealed no significant differences among groups, regardless of radiation regimen. The data demonstrate that caspase-3 activation initially triggered by both forms of acute radiation was greatly elevated in the skin nearly two months after whole-body exposure. In addition, LDR γ-ray priming ameliorated this response.


Asunto(s)
Rayos gamma , Protones , Traumatismos Experimentales por Radiación/enzimología , Piel/efectos de la radiación , Animales , Apoptosis , Caspasa 3/metabolismo , Fragmentación del ADN , Relación Dosis-Respuesta en la Radiación , Femenino , Ratones , Ratones Endogámicos C57BL , Tolerancia a Radiación/efectos de la radiación , Piel/enzimología , Piel/patología , Irradiación Corporal Total
5.
Radiat Res ; 180(4): 340-50, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24033191

RESUMEN

A recent report shows that more than 30% of the astronauts returning from Space Shuttle missions or the International Space Station (ISS) were diagnosed with eye problems that can cause reduced visual acuity. We investigate here whether spaceflight environment-associated retinal damage might be related to oxidative stress-induced mitochondrial apoptosis. Female C57BL/6 mice were flown in the space shuttle Atlantis (STS-135), and within 3-5 h of landing, the spaceflight and ground-control mice, similarly housed in animal enclosure modules (AEMs) were euthanized and their eyes were removed for analysis. Changes in expression of genes involved in oxidative stress, mitochondrial and endothelial cell biology were examined. Apoptosis in the retina was analyzed by caspase-3 immunocytochemical analysis and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay. Levels of 4-hydroxynonenal (4-HNE) protein, an oxidative specific marker for lipid peroxidation were also measured. Evaluation of spaceflight mice and AEM ground-control mice showed that expression of several genes playing central roles in regulating the mitochondria-associated apoptotic pathway were significantly altered in mouse ocular tissue after spaceflight compared to AEM ground-control mice. In addition, the mRNA levels of several genes, which are responsible for regulating the production of reactive oxygen species were also significantly up-regulated in spaceflight samples compared to AEM ground-control mice. Further more, the level of HNE protein was significantly elevated in the retina after spaceflight compared to controls. Our results also revealed that spaceflight conditions induced significant apoptosis in the retina especially inner nuclear layer (INL) and ganglion cell layer (GCL) compared to AEM ground controls. The data provided the first evidence that spaceflight conditions induce oxidative damage that results in mitochondrial apoptosis in the retina. This data suggest that astronauts may be at increased risk for late retinal degeneration.


Asunto(s)
Ambiente , Ojo/citología , Ojo/efectos de la radiación , Mitocondrias/metabolismo , Mitocondrias/efectos de la radiación , Estrés Oxidativo/efectos de la radiación , Vuelo Espacial , Animales , Células Endoteliales/citología , Células Endoteliales/metabolismo , Células Endoteliales/efectos de la radiación , Ojo/metabolismo , Femenino , Ratones , Ratones Endogámicos C57BL , Oxidación-Reducción/efectos de la radiación , Transcriptoma/efectos de la radiación
6.
PLoS One ; 8(9): e75097, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24069384

RESUMEN

Our previous results with flight (FLT) mice showed abnormalities in thymuses and spleens that have potential to compromise immune defense mechanisms. In this study, the organs were further evaluated in C57BL/6 mice after Space Shuttle Atlantis returned from a 13-day mission. Thymuses and spleens were harvested from FLT mice and ground controls housed in similar animal enclosure modules (AEM). Organ and body mass, DNA fragmentation and expression of genes related to T cells and cancer were determined. Although significance was not obtained for thymus mass, DNA fragmentation was greater in the FLT group (P<0.01). Spleen mass alone and relative to body mass was significantly decreased in FLT mice (P<0.05). In FLT thymuses, 6/84 T cell-related genes were affected versus the AEM control group (P<0.05; up: IL10, Il18bp, Il18r1, Spp1; down: Ccl7, IL6); 15/84 cancer-related genes had altered expression (P<0.05; up: Casp8, FGFR2, Figf, Hgf, IGF1, Itga4, Ncam1, Pdgfa, Pik3r1, Serpinb2, Sykb; down: Cdc25a, E2F1, Mmp9, Myc). In the spleen, 8/84 cancer-related genes were affected in FLT mice compared to AEM controls (P<0.05; up: Cdkn2a; down: Birc5, Casp8, Ctnnb1, Map2k1, Mdm2, NFkB1, Pdgfa). Pathway analysis (apoptosis signaling and checkpoint regulation) was used to map relationships among the cancer-related genes. The results showed that a relatively short mission in space had a significant impact on both organs. The findings also indicate that immune system aberrations due to stressors associated with space travel should be included when estimating risk for pathologies such as cancer and infection and in designing appropriate countermeasures. Although this was the historic last flight of NASA's Space Shuttle Program, exploration of space will undoubtedly continue.


Asunto(s)
Vuelo Espacial , Bazo/fisiología , Timo/fisiología , Animales , Fragmentación del ADN , Conducta Alimentaria , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Ratones , Modelos Biológicos , Proteínas Oncogénicas/genética , Proteínas Oncogénicas/metabolismo , Tamaño de los Órganos , Transducción de Señal , Bazo/anatomía & histología , Timo/anatomía & histología , Ingravidez
7.
Int J Radiat Biol ; 86(2): 145-63, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20148700

RESUMEN

PURPOSE: We examined the effects of manganese (III) meso-tetrakis (diethyl-2-5-imidazole) porphyrin, a metalloporphyrin antioxidant (MPA), on neural tissue radiation toxicity in vivo and on tumour cell radiosensitivity in vitro. MATERIALS AND METHODS: MPA was administered directly into the right lateral ventricle of young adult, male Sprague-Dawley rats (0 or 3.4 microg) 3 h before treatment with a single fraction, 100 Gy radiation dose delivered to the left brain hemisphere. The effects of treatment on radiation responses were assessed at different time points following irradiation. RESULTS: MPA treatment prior to brain irradiation protected against acute radiation-induced apoptosis and ameliorated delayed damage to the blood-brain barrier and radiation necrosis, but without producing a discernible increase in tissue superoxide disumtase (SOD) activity. In vitro, MPA pretreatment protected against radiation-induced apoptosis in primary neuronal cultures and increased clonogenic survival of irradiated rat glioma C6 cells, but had no discernible effect on radiation-induced DNA double-strand breaks. MPA, a low molecular weight SOD mimic, significantly increased mitochondrial SOD activity in C6 cells, but not total cellular SOD activity. MPA up-regulated C6 expression of heme-oxygenase 1 (HO-1), an endogenous radioprotectant, but had no effect on HO-1 levels in human astrocytoma U-251 cells, human prostatic carcinoma LNCaP cells, or primary rat brain microvascular endothelial cells in vitro, nor on brain tissue HO-1 expression levels in vivo. CONCLUSIONS: Metalloporphyrin antioxidants merit further exploration as adjunctive radioprotectants for cranial radiotherapy/radiosurgery applications, although the potential for tumour protection must be carefully considered.


Asunto(s)
Antioxidantes/farmacología , Encéfalo/efectos de los fármacos , Encéfalo/efectos de la radiación , Metaloporfirinas/farmacología , Traumatismos Experimentales por Radiación/prevención & control , Protectores contra Radiación/farmacología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/efectos de la radiación , Encéfalo/metabolismo , Encéfalo/patología , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/patología , Lesiones Encefálicas/prevención & control , Línea Celular Tumoral , Células Cultivadas , Roturas del ADN de Doble Cadena , Hemo Oxigenasa (Desciclizante)/metabolismo , Humanos , Masculino , Neuroglía/citología , Neuroglía/efectos de los fármacos , Neuroglía/efectos de la radiación , Neuronas/citología , Neuronas/efectos de los fármacos , Neuronas/efectos de la radiación , Traumatismos Experimentales por Radiación/metabolismo , Traumatismos Experimentales por Radiación/patología , Tolerancia a Radiación/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Superóxido Dismutasa/metabolismo
8.
J Immunol ; 176(9): 5438-45, 2006 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-16622011

RESUMEN

The onset of activation in Th cells is triggered by localized co-engagement of TCRs and the coreceptor CD4. A CD4 crystal suggested that CD4 may form dimers in some circumstances. In this study, we use live-cell fluorescence resonance energy transfer imaging to demonstrate that CD4 dimers are present at a basal level on the cell surface and accumulate at the synapse. Mechanistically, we reveal two conditions under which dimers are highly relevant. First, CD4 dimers are more proficient in mediating prolonged cell contacts with APCs in the presence or absence of Ag. This is consistent with a model whereby the dimer functions to increase T-APC avidity. Second, we show that dimer mutations result in an increased level of an inactive lckTyr(505) bound to the CD4 molecule relative to dimer-competent CD4. We also find a consistent defect in signaling onset in these cells. This supports a role for CD4 dimerization in maintaining active signaling machinery. We suggest that modulation of the dimer/monomer ratio may permit tuning of activation thresholds during initial engagement.


Asunto(s)
Antígenos CD4/inmunología , Antígenos CD4/metabolismo , Activación de Linfocitos/inmunología , Linfocitos T/inmunología , Linfocitos T/metabolismo , Animales , Células Presentadoras de Antígenos/inmunología , Células Presentadoras de Antígenos/metabolismo , Antígenos CD4/genética , Calcio/metabolismo , Línea Celular , Dimerización , Transferencia Resonante de Energía de Fluorescencia , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/metabolismo , Ratones , Mutación/genética , Fosforilación , Unión Proteica , Transducción de Señal
9.
Semin Immunol ; 17(1): 65-75, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15582489

RESUMEN

A tantalizing feature of the 'immunological synapse' is the segregation of transmembrane proteins into activating clusters and their underlying signalosomes. The mechanisms by which transmembrane proteins are initially recruited to and then stably segregated at the synapse remains an outstanding question in the field; and one likely to reveal key modes of signaling regulation. Ongoing real-time imaging approaches and a refocusing of efforts upon understanding the basic cell biology of T cells have all contributed to a developing model of T cell behavior; elementary TCR-derived signaling quickly feeds back into the basic cellular programs controlling cell shape, adhesiveness, motility, as well as some poorly understood aspects of membrane fluidity and segregation. It is increasingly clear that the mechanisms for control at this level are shared between T cells and other cell types and may not be revealed in differential genomic screening. To this end, imaging-based genetic screens are now coming online to aid in identifying the ubiquitous proteins that function at polarized signaling surfaces.


Asunto(s)
Comunicación Celular/inmunología , Uniones Intercelulares/inmunología , Activación de Linfocitos/inmunología , Microdominios de Membrana/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Transducción de Señal/inmunología , Linfocitos T/inmunología , Citoesqueleto/inmunología , Humanos , Linfocitos T/metabolismo
10.
Anesthesiology ; 100(5): 1160-6, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15114213

RESUMEN

BACKGROUND: This study examined long-term outcome from severe forebrain ischemia in the rat, as a function of anesthetic given during the ischemic injury. METHODS: Rats were subjected to 10 min of near-complete forebrain ischemia while anesthetized with either 1.4% isoflurane or 70% nitrous oxide-fentanyl. Neurologic and histologic outcomes were measured at 5 days, 3 weeks, or 3 months after ischemia. RESULTS: At 5 days, isoflurane-anesthetized rats had less damage than did fentanyl-nitrous oxide-anesthetized rats (mean +/- SD, percent alive hippocampal CA1 neurons = 58+/-29 vs. 20+/-16, respectively; P = 0.011). This was accompanied by improved motor function in the isoflurane group (P = 0.002). At 3 weeks, there was no difference between groups for either outcome variable (percent alive CA1 neurons = 35+/-26 and 36+/-28 for isoflurane and fentanyl-nitrous oxide, respectively). Similarly, at 3 months, there was no difference between groups (percent alive CA1 neurons = 56+/-27 and 60+/-27 for isoflurane and fentanyl-nitrous oxide, respectively). Morris water maze performance at 3 months was similar between anesthetic groups and was also similar to sham performance. The percent alive CA1 neurons in the fentanyl-nitrous oxide group increased with duration of recovery (P = 0.004). There were no differences among isoflurane groups over time (5 days vs. 3 weeks, P = 0.26; 5 days vs. 3 months, P = 0.99; 3 week vs. 3 months, P = 0.32). CONCLUSIONS: This study found no change in the percent alive CA1 hippocampal neurons as a function of duration of recovery from severe forebrain ischemia in isoflurane anesthetized rats. In contrast, the percent alive CA1 neurons in fentanyl-nitrous oxide-anesthetized rats tripled over 3 months of recovery. The natural history of long-term responses to forebrain ischemia requires further study before conclusions can be drawn with respect to the permanence of isoflurane neuroprotection.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Fentanilo/uso terapéutico , Isoflurano/uso terapéutico , Óxido Nitroso/uso terapéutico , Prosencéfalo/efectos de los fármacos , Anestesia/métodos , Animales , Isquemia Encefálica/patología , Muerte Celular/efectos de los fármacos , Muerte Celular/fisiología , Fentanilo/farmacología , Isoflurano/farmacología , Masculino , Óxido Nitroso/farmacología , Prosencéfalo/patología , Prosencéfalo/fisiología , Ratas , Ratas Sprague-Dawley , Tiempo de Reacción/efectos de los fármacos , Tiempo de Reacción/fisiología , Tiempo
11.
J Immunol ; 169(11): 6261-8, 2002 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-12444132

RESUMEN

The CD4 molecule plays a key role in the development and activation of helper T cells. Dimerization and oligomerization is often a necessary step in the function of several cell surface receptors. Herein, we provide direct biochemical evidence confirming the presence of CD4 as dimers in transfected cells from hemopoetic and fibroblastic origin as well as in primary T cells. Such dimers are also observed with murine CD4 confirming selective pressure during evolution to maintain such a structure. Using a series of point mutations, we have precisely mapped the dimerization site at residues K318 and Q344 within the fourth extracellular domain of CD4. These residues are highly conserved and their mutation results in interference with dimer formation. More importantly, we demonstrate that dimer formation is essential for the coligand and coreceptor functions of CD4 in T cell activation. These data strongly suggest that CD4 dimerization is necessary for helper T cell function.


Asunto(s)
Antígenos CD4/química , Antígenos CD4/metabolismo , Linfocitos T CD4-Positivos/inmunología , Activación de Linfocitos , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Sitios de Unión/genética , Antígenos CD4/genética , Células COS , Línea Celular , ADN Complementario/genética , Dimerización , Humanos , Ratones , Modelos Moleculares , Datos de Secuencia Molecular , Mutación Puntual , Estructura Terciaria de Proteína , Receptores de Antígenos de Linfocitos T/metabolismo , Selección Genética , Linfocitos T Colaboradores-Inductores/inmunología , Transfección
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