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1.
Nature ; 618(7967): 1065-1071, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37198476

RESUMEN

Eukaryotic cells can undergo different forms of programmed cell death, many of which culminate in plasma membrane rupture as the defining terminal event1-7. Plasma membrane rupture was long thought to be driven by osmotic pressure, but it has recently been shown to be in many cases an active process, mediated by the protein ninjurin-18 (NINJ1). Here we resolve the structure of NINJ1 and the mechanism by which it ruptures membranes. Super-resolution microscopy reveals that NINJ1 clusters into structurally diverse assemblies in the membranes of dying cells, in particular large, filamentous assemblies with branched morphology. A cryo-electron microscopy structure of NINJ1 filaments shows a tightly packed fence-like array of transmembrane α-helices. Filament directionality and stability is defined by two amphipathic α-helices that interlink adjacent filament subunits. The NINJ1 filament features a hydrophilic side and a hydrophobic side, and molecular dynamics simulations show that it can stably cap membrane edges. The function of the resulting supramolecular arrangement was validated by site-directed mutagenesis. Our data thus suggest that, during lytic cell death, the extracellular α-helices of NINJ1 insert into the plasma membrane to polymerize NINJ1 monomers into amphipathic filaments that rupture the plasma membrane. The membrane protein NINJ1 is therefore an interactive component of the eukaryotic cell membrane that functions as an in-built breaking point in response to activation of cell death.


Asunto(s)
Moléculas de Adhesión Celular Neuronal , Muerte Celular , Membrana Celular , Factores de Crecimiento Nervioso , Animales , Humanos , Ratones , Moléculas de Adhesión Celular Neuronal/química , Moléculas de Adhesión Celular Neuronal/genética , Moléculas de Adhesión Celular Neuronal/metabolismo , Moléculas de Adhesión Celular Neuronal/ultraestructura , Membrana Celular/metabolismo , Membrana Celular/patología , Membrana Celular/ultraestructura , Microscopía por Crioelectrón , Factores de Crecimiento Nervioso/química , Factores de Crecimiento Nervioso/genética , Factores de Crecimiento Nervioso/metabolismo , Factores de Crecimiento Nervioso/ultraestructura , Mutagénesis Sitio-Dirigida , Biopolímeros/química , Biopolímeros/genética , Biopolímeros/metabolismo
2.
EMBO J ; 43(7): 1164-1186, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38396301

RESUMEN

Ferroptosis is a regulated form of necrotic cell death caused by iron-dependent accumulation of oxidized phospholipids in cellular membranes, culminating in plasma membrane rupture (PMR) and cell lysis. PMR is also a hallmark of other types of programmed necrosis, such as pyroptosis and necroptosis, where it is initiated by dedicated pore-forming cell death-executing factors. However, whether ferroptosis-associated PMR is also actively executed by proteins or driven by osmotic pressure remains unknown. Here, we investigate a potential ferroptosis role of ninjurin-1 (NINJ1), a recently identified executor of pyroptosis-associated PMR. We report that NINJ1 oligomerizes during ferroptosis, and that Ninj1-deficiency protects macrophages and fibroblasts from ferroptosis-associated PMR. Mechanistically, we find that NINJ1 is dispensable for the initial steps of ferroptosis, such as lipid peroxidation, channel-mediated calcium influx, and cell swelling. In contrast, NINJ1 is required for early loss of plasma membrane integrity, which precedes complete PMR. Furthermore, NINJ1 mediates the release of cytosolic proteins and danger-associated molecular pattern (DAMP) molecules from ferroptotic cells, suggesting that targeting NINJ1 could be a therapeutic option to reduce ferroptosis-associated inflammation.


Asunto(s)
Alarminas , Ferroptosis , Humanos , Necrosis/metabolismo , Muerte Celular , Membrana Celular/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Moléculas de Adhesión Celular Neuronal/metabolismo
3.
J Strength Cond Res ; 38(5): 881-890, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38219228

RESUMEN

ABSTRACT: Ben Othman, A, Anvar, SH, Aragão-Santos, JC, Behm, DG, and Chaouachi, A. Relative cross-education training effects of male youth exceed male adults. J Strength Cond Res 38(5): 881-890, 2024-Cross-education has been studied extensively with adults, examining the training effects on contralateral homologous muscles. There is less information on the cross-education effects on contralateral heterologous muscles and scant information comparing these responses between adults and youth. The objective was to compare cross-education training effects in male youth and adults to contralateral homologous and heterologous muscles. Forty-two male children (10-13-years) and 42 adults (18-21-years) were tested before and following an 8-week unilateral, dominant or nondominant arm, chest press (CP) training program or control group (14 subjects each). Unilateral testing assessed dominant and nondominant limb strength with leg press and CP 1 repetition maximum (1RM), knee extensors, elbow extensors (EE), elbow flexors, and handgrip maximum voluntary isometric contraction (MVIC) strength and shot put distance and countermovement jump height. Upper-body tests demonstrated large magnitude increases, with children overall exceeding adults ( p = 0.05- p < 0.0001, η2 : 0.51, 10.4 ± 11.1%). The dominant trained limb showed significantly higher training adaptations than the nondominant limb for the adults with CP 1RM ( p = 0.03, η2 : 0.26, 6.7 ± 11.5%) and EE ( p = 0.008, η2 : 0.27, 8.8 ± 10.3%) MVIC force. Unilateral CP training induced significantly greater training adaptations with the ipsilateral vs. contralateral limb ( p = 0.008, η2 : 0.93, 27.8 ± 12.7%). In conclusion, children demonstrated greater training adaptations than adults, upper-body strength increased with no significant lower-body improvements, and ipsilateral training effects were greater than contralateral training in adults.


Asunto(s)
Fuerza Muscular , Músculo Esquelético , Entrenamiento de Fuerza , Humanos , Masculino , Adolescente , Adulto Joven , Fuerza Muscular/fisiología , Niño , Entrenamiento de Fuerza/métodos , Músculo Esquelético/fisiología , Contracción Isométrica/fisiología , Fuerza de la Mano/fisiología
4.
Parasitol Res ; 122(2): 395-411, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36534238

RESUMEN

Wild rodent species are naturally infected by Schistosoma mansoni; however, the genetic characterization of the parasite, its parasitological features, and its role in human schistosomiasis are poorly understood. In this study, we isolated and characterized Schistosoma from naturally infected Holochilus sciureus, called HS strain, collected from a schistosomiasis endemic region in Maranhão State, Brazil. To isolate the parasite, miracidia obtained from the livers of H. sciureus were used to infect Biomphalaria glabrata of sympatric (called SB) and allopatric (called BH) strains, and the produced cercariae were subcutaneously inoculated into hamsters and/or BALB/c mice. Parasitological kinetics in experimentally infected hosts were evaluated, and the tRNACys-12S (referred to as 16S herein) and cox 1 regions of mtDNA from isolated worms were amplified and sequenced. Only miracidia obtained from infected mice, but not from hamsters, were capable of infecting B. glabrata, allowing maintenance of the isolated parasite. Cox1 and 16S mtDNA sequences showed 100% similarity with S. mansoni, and phylogenetic analysis showed that the HS strain of S. mansoni forms an assemblage with isolates from America and Kenya, confirming the conspecificity. Experimental infection of B. glabrata SB with S. mansoni HS resulted in two peaks of cercariae shedding at 45 and 70 days post-infection (dpi) and caused higher mortality than in B. glabrata BH. The worm recovery rate in mice was approximately 13%, and the peak of egg elimination occurred at the 10th week post-infection. Therefore, S. mansoni obtained from H. sciureus was successfully isolated, genetically characterized, and maintained in mice, allowing further study of this schistosome strain.


Asunto(s)
Biomphalaria , Esquistosomiasis mansoni , Trematodos , Animales , Humanos , Ratones , Schistosoma mansoni/genética , Esquistosomiasis mansoni/parasitología , Arvicolinae , Roedores/parasitología , Brasil , Filogenia , Biomphalaria/parasitología , Sigmodontinae , Cercarias
5.
J Sports Sci Med ; 22(2): 180-188, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37293416

RESUMEN

Over the last decade, acute increases in range of motion (ROM) in response to foam rolling (FR) have been frequently reported. Compared to stretching, FR-induced ROM increases were not typically accompanied by a performance (e.g., force, power, endurance) deficit. Consequently, the inclusion of FR in warm-up routines was frequently recommended, especially since literature pointed out non-local ROM increases after FR. However, to attribute ROM increases to FR it must be ensured that such adaptations do not occur as a result of simple warm-up effects, as significant increases in ROM can also be assumed as a result of active warm-up routines. To answer this research question, 20 participants were recruited using a cross-over design. They performed 4x45 seconds hamstrings rolling under two conditions; FR, and sham rolling (SR) using a roller board to imitate the foam rolling movement without the pressure of the foam rolling. They were also tested in a control condition. Effects on ROM were tested under passive, active dynamic as well as ballistic conditions. Moreover, to examine non-local effects the knee to wall test (KtW) was used. Results showed that both interventions provided significant, moderate to large magnitude increases in passive hamstrings ROM and KtW respectively, compared to the control condition (p = 0.007-0.041, d = 0.62-0.77 and p = 0.002-0.006, d = 0.79-0.88, respectively). However, the ROM increases were not significantly different between the FR and the SR condition (p = 0.801, d = 0.156 and p = 0.933, d = 0.09, respectively). No significant changes could be obtained under the active dynamic (p = 0.65) while there was a significant decrease in the ballistic testing condition with a time effect (p < 0.001). Thus, it can be assumed that potential acute increases in ROM cannot be exclusively attributed to FR. It is therefore speculated that warm up effects could be responsible independent of FR or imitating the rolling movement, which indicates there is no additive effect of FR or SR to the dynamic or ballistic range of motion.


Asunto(s)
Músculos Isquiosurales , Ejercicio de Calentamiento , Humanos , Músculos Isquiosurales/fisiología , Rango del Movimiento Articular/fisiología , Estudios Cruzados , Movimiento
6.
EMBO J ; 37(6)2018 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-29459437

RESUMEN

Pathogenic and commensal Gram-negative bacteria produce and release outer membrane vesicles (OMVs), which present several surface antigens and play an important role for bacterial pathogenesis. OMVs also modulate the host immune system, which makes them attractive as vaccine candidates. At the cellular level, OMVs are internalized by macrophages and deliver lipopolysaccharide (LPS) into the host cytosol, thus activating the caspase-11 non-canonical inflammasome. Here, we show that OMV-induced inflammasome activation requires TLR4-TRIF signaling, the production of type I interferons, and the action of guanylate-binding proteins (GBPs), both in macrophages and in vivo Mechanistically, we find that isoprenylated GBPs associate with the surface of OMVs or with transfected LPS, indicating that the key factor that determines GBP recruitment to the Gram-negative bacterial outer membranes is LPS itself. Our findings provide new insights into the mechanism by which GBPs target foreign surfaces and reveal a novel function for GBPs in controlling the intracellular detection of LPS derived from extracellular bacteria in the form of OMVs, thus extending their function as a hub between cell-autonomous immunity and innate immunity.


Asunto(s)
Bacterias/inmunología , Membrana Celular/inmunología , Proteínas de Unión al GTP/inmunología , Inflamasomas/inmunología , Lipopolisacáridos/inmunología , Animales , Proteínas de Unión al GTP/genética , Ratones Endogámicos C57BL , Ratones Noqueados
7.
Int J Sports Med ; 43(8): 715-720, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35088394

RESUMEN

Vegetarian diets have become popular among athletes and active individuals and can have advantages for physical performance, but the results are still conflicting regarding muscle strength and power. The aim of this study was to evaluate the diet and physical performance of vegetarians through tests of dynamic, isometric, and relative strength; muscle power; and aerobic capacity. In this cross-sectional study, 32 vegetarians and 26 omnivores, who were physically active, were evaluated for the Healthy Eating Index and performance tested back squat, handgrip strength, isometric deadlift strength, jump with countermovement, and maximum aerobic speed (MAS). Improved diet quality (63.24±14.40 vs. 54±16.80, p<0.05), greater relative strength (1.03±0.23 vs. 0.91±0.12, p<0.05), and greater jump height (43.77±9.91 vs. 38.45±8.92, p<0.05) were found among vegetarians. No difference was seen in MAS (13.5±2 vs. 11±3, p>0.05) or isometric strength of upper limbs (77±29 vs. 70±50, p>0.05) and lower limbs (89±41 vs. 97±50, p>0.05). Thus, we conclude that vegetarians and omnivores show similar performance in strength and aerobic capacity, but in our sample, vegetarians show higher levels of relative strength and power.


Asunto(s)
Fuerza de la Mano , Vegetarianos , Estudios Transversales , Dieta/métodos , Dieta Vegetariana/métodos , Humanos , Extremidad Inferior
8.
Int J Phytoremediation ; 24(5): 474-482, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34353182

RESUMEN

Biochar can enhance the phytoremediation of copper-contaminated soils by improving soil quality and increasing plant growth. However, the impact of biochar varies with the biomass feedstock and soil condition. Our study investigated the effect of biochar from orange bagasse-OBB and coconut husk-CHB and two copper concentrations (0.17 mg kg-1-CLS soil; 100 mg kg-1- CTS soil) on plant growth, copper uptake, and physiological response of Brassica juncea. The low- and high-Cu soils were also tested without biochar. We evaluated plant biomass, plant Cu, N and P, chlorophyll content, and chlorophyll's transient fluorescence. Plant growth was meager without biochar, indicating that the high Cu concentration was not the only limiting factor. Biochar (OBB and CHB) increased shoot mass by 300-574% and root mass by 50-2900%, and improved chlorophyll content and photosynthetic activity by 6-16%. Both biochars were efficient in the low-Cu soil as they increased plant biomass, shoot copper concentration, and translocation factor. In the high-Cu soil, both biochars increased plant biomass and copper uptake and reduced shoot copper concentration and translocation factor. The CHB and OBB removed 342% and 783% more Cu from the contaminated soil than the Control; therefore, the OBB was proven to be the best choice for phytoremediation.Novelty statement Our study showed that the orange bagasse biochar can be successfully applied for the phytoremediation of copper-contaminated soils using Brassica juncea. The orange bagasse biochar was effective regardless of the copper level in the soil, removing twice as much copper as the coconut biochar; therefore, it can speed up the process and reduce the time needed to clean up the site. HighlightsBiochar significantly improved the plant's physiological responseBiochar increased plant growth and copper uptake in the contaminated soilTranslocation factor was increased in the clean soil and reduced in the contaminated soilBiochar from orange bagasse is more effective than coconut husk for phytoremediation.


Asunto(s)
Planta de la Mostaza , Contaminantes del Suelo , Biodegradación Ambiental , Biomasa , Carbón Orgánico , Cobre , Suelo , Contaminantes del Suelo/análisis
9.
J Contemp Dent Pract ; 23(10): 979-983, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37073909

RESUMEN

AIM: This study aimed to evaluate the spatial location of the second mesiobuccal canal (MB2) of maxillary molars (MMs), using cone-beam computed tomography (CBCT), in a Brazilian subpopulation. MATERIALS AND METHODS: The CBCT examination of 250 patients performed on the Eagle 3D device was analyzed, totaling 787 MMs. Using the Radiant Dicom Viewer software, measurements were made of the distances, in millimeters (mm), between the first mesiobuccal canal (MB1), MB2, and palatal (P) canal inputs, from the axial sections. The Image J software evaluated the angle formed by the lines. The data obtained were analyzed statistically by Fisher's exact and Chi-square tests with a significance of 5%. RESULTS: The prevalence of MB2 canals observed was 76.44 and 41.73% in the first and second molars (1MMs and 2MMs), respectively (p < 0.05). The average of the distances and angles performed, for the location of the MB2 canals of the analyzed teeth, were MB1-P = 5.83 mm, MB1-MB2 = 2.31 mm, and MB2 for the intersection of the connecting distance from MB2-T = 0.90 mm. The average angle formed between the MB1-P and MB1-MB2 distances was 25.89° and 19.68° for the 1MMs and 2MMs, respectively. It was also observed that 91.4 and 75.4% of the maxillary 1MMs and 2MMs, respectively, presented the MB2 canals mesially located at the line connecting the MB1-P canals (p < 0.0001). CONCLUSION: The MB2 canals were located mesially to the MB1 canal with an average distance of 2 mm between the canals. CLINICAL SIGNIFICANCE: The anatomical knowledge of the spatial location of the MB2 canal in different ethnicities is important for the planning and execution of endodontic treatment.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Diente Molar , Humanos , Brasil , Diente Molar/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos , Cavidad Pulpar/diagnóstico por imagen , Maxilar/diagnóstico por imagen
10.
Arch Psychiatr Nurs ; 34(5): 405-411, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33032766

RESUMEN

INTRODUCTION: A better understanding of the meanings that adolescents associate with suicide, contributes to the development of psychotherapeutic intervention programs to be implemented by nurse specialists in mental health and psychiatric nursing. Therefore, adolescents need to characterize their adopted suicidal behaviors and identify the personal characteristics that contribute to this same behavior. METHODOLOGY: A descriptive, exploratory, and qualitative study was conducted with 33 adolescents with suicidal behavior, hospitalized in a child psychiatry unit. Data were collected through a structured interview, and data treatment used the content analysis technique. RESULTS: Suicidal behaviors are characterized according to causality, meaning, and intent. Causality is mostly related to psychological factors (sadness, desperation, mental suffering, internal pain, emptiness, and rejection). As to the meaning, suicidal behavior is understood as an escape but also as a personal choice, sometimes regarded as rational. In what concerns intent, the intent to die is the most frequently reported. The most-reported personal characteristics which contributed to the suicidal behavior are feelings of exclusion, rejection, and humiliation, and also introversion. CONCLUSIONS: The results point to the need to reflect on the perceptions of adolescents with suicidal behavior. The current intervention strategies should be adjusted especially through the identification of the signs associated with mental distress in adolescents and the training of gatekeepers, contributing to productive and congruent suicide prevention in this vulnerable group.


Asunto(s)
Conducta del Adolescente/psicología , Enfermería Psiquiátrica , Psicología , Prevención del Suicidio , Intento de Suicidio/psicología , Adolescente , Adolescente Hospitalizado/psicología , Femenino , Humanos , Masculino , Trastornos Mentales , Servicio de Psiquiatría en Hospital , Investigación Cualitativa
11.
Eur J Nucl Med Mol Imaging ; 46(5): 1081-1091, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30603987

RESUMEN

PURPOSE: The aims of this study were to develop a prostate-specific membrane antigen (PSMA) ligand for labelling with different radioisotopes of lead and to obtain an approximation of the dosimetry of a simulated 212Pb-based alpha therapy using its 203Pb imaging analogue. METHODS: Four novel Glu-urea-based ligands containing the chelators p-SCN-Bn-TCMC or DO3AM were synthesized. Affinity and PSMA-specific internalization were studied in C4-2 cells, and biodistribution in C4-2 tumour-bearing mice. The most promising compound, 203Pb-CA012, was transferred to clinical use. Two patients underwent planar scintigraphy scans at 0.4, 4, 18, 28 and 42 h after injection, together with urine and blood sampling. The time-activity curves of source organs were extrapolated from 203Pb to 212Pb and the calculated residence times of 212Pb were forwarded to its unstable daughter nuclides. QDOSE and OLINDA were used for dosimetry calculations. RESULTS: In vitro, all ligands showed low nanomolar binding affinities for PSMA. CA09 and CA012 additionally showed specific ligand-induced internalization of 27.4 ± 2.4 and 15.6 ± 2.1 %ID/106 cells, respectively. The 203Pb-labelled PSMA ligands were stable in serum for 72 h. In vivo, CA012 showed higher specific uptake in tumours than in other organs, and particularly showed rapid kidney clearance from 5.1 ± 2.5%ID/g at 1 h after injection to 0.9 ± 0.1%ID/g at 24 h. In patients, the estimated effective dose from 250-300 MBq of diagnostic 203Pb-CA012 was 6-7 mSv. Assuming instant decay of daughter nuclides, the equivalent doses projected from a therapeutic activity of 100 MBq of 212Pb-CA012 were 0.6 SvRBE5 to the red marrow, 4.3 SvRBE5 to the salivary glands, 4.9 SvRBE5 to the kidneys, 0.7 SvRBE5 to the liver and 0.2 SvRBE5 to other organs; representative tumour lesions averaged 13.2 SvRBE5 (where RBE5 is relative biological effectiveness factor 5). Compared to clinical experience with 213Bi-PSMA-617 and 225Ac-PSMA-617, the projected maximum tolerable dose was about 150 MBq per cycle. CONCLUSION: 212Pb-CA012 is a promising candidate for PSMA-targeted alpha therapy of prostate cancer. The dosimetry estimate for radiopharmaceuticals decaying with the release of unstable daughter nuclides has some inherent limitations, thus clinical translation should be done cautiously.


Asunto(s)
Partículas alfa/uso terapéutico , Antígenos de Superficie/metabolismo , Glutamato Carboxipeptidasa II/metabolismo , Radioisótopos de Plomo/uso terapéutico , Animales , Línea Celular Tumoral , Humanos , Marcaje Isotópico , Ligandos , Ratones , Radiometría
12.
Cell Microbiol ; 20(4)2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29250873

RESUMEN

Salmonella enterica induces membrane ruffling and genesis of macropinosomes during its interactions with epithelial cells. This is achieved through the type three secretion system-1, which first mediates bacterial attachment to host cells and then injects bacterial effector proteins to alter host behaviour. Next, Salmonella enters into the targeted cell within an early membrane-bound compartment that matures into a slow growing, replicative niche called the Salmonella Containing Vacuole (SCV). Alternatively, the pathogen disrupts the membrane of the early compartment and replicate at high rate in the cytosol. Here, we show that the in situ formed macropinosomes, which have been previously postulated to be relevant for the step of Salmonella entry, are key contributors for the formation of the mature intracellular niche of Salmonella. We first clarify the primary mode of type three secretion system-1 induced Salmonella entry into epithelial cells by combining classical fluorescent microscopy with cutting edge large volume electron microscopy. We observed that Salmonella, similarly to Shigella, enters epithelial cells inside tight vacuoles rather than in large macropinosomes. We next apply this technology to visualise rupturing Salmonella containing compartments, and we use extended time-lapse microscopy to establish early markers that define which Salmonella will eventually hyper replicate. We show that at later infection stages, SCVs harbouring replicating Salmonella have previously fused with the in situ formed macropinosomes. In contrast, such fusion events could not be observed for hyper-replicating Salmonella, suggesting that fusion of the Salmonella entry compartment with macropinosomes is the first committed step of SCV formation.


Asunto(s)
Células Epiteliales/microbiología , Células Epiteliales/ultraestructura , Infecciones por Salmonella/microbiología , Infecciones por Salmonella/patología , Salmonella enterica/fisiología , Citosol/metabolismo , Citosol/ultraestructura , Células HeLa , Interacciones Huésped-Patógeno , Humanos
13.
J Sex Med ; 16(7): 1018-1028, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31010779

RESUMEN

INTRODUCTION: 10% of the world's population suffers from chronic kidney disease. Kidney transplants provide an improvement in the quality of life of those patients. Sexual dysfunction is common after kidney transplantation, and its etiology is presumed to be multifactorial. It has a negative impact on sexual satisfaction and health-related quality-of-life. The integration of a new organ into the body can imply an adjustment of body image, which may eventually have a negative influence on intimacy and sexual behaviors. AIM: To evaluate male sexual function, sexual satisfaction, and body image satisfaction among a convenience sample of patients who have had a kidney transplant. METHODS: This is a cross-sectional study that included 460 patients, from a single healthcare center, who had undergone a kidney transplant procedure >4 weeks ago. A total of 112 respondents (mean = 55.5 years, SD = 11.4) answered the questionnaires properly. MAIN OUTCOME MEASURES: All recruited patients answered a self-reported sociodemographic questionnaire, in addition to the International Index of Erectile function, the New Scale of Sexual Satisfaction, the Brief Symptom Inventory, and the Body Image Scale. RESULTS: A correlation was found between sexual function and sexual satisfaction (r = 0.598, P < .001, n = 112), as well as between body image satisfaction and sexual function (r = -0.193, P = .042, n = 112). The length of time after a kidney transplant (≤ or >36 months) was not associated with a difference in sexual functioning or sexual satisfaction. CLINICAL IMPLICATIONS: This study showed the obvious implications of sexual function on sexual satisfaction, which should alert healthcare professionals to the importance of identifying and managing sexual dysfunction in patients with chronic kidney disease, to optimize their global and sexual health satisfaction. STRENGTH & LIMITATIONS: This study identified a high prevalence of sexual dysfunction among kidney transplant recipients. This should reinforce the need for the medical community to evaluate the quality-of-life domains of patients with chronic disease. There is still a lack of information concerning any longitudinal evaluation of kidney transplant patients' sexual function and the effects that this surgery has on sexuality. CONCLUSIONS: This study corroborated the severe effects that kidney transplant patients often report regarding their sexuality. Among the patients who participated in the study, sexual function proved to be relevant in relation to sexual satisfaction. Mota RL, Fonseca R, Santos JC, et al. Sexual Dysfunction and Satisfaction in Kidney Transplant Patients. J Sex Med 2019;16:1018-1028.


Asunto(s)
Trasplante de Riñón , Orgasmo , Conducta Sexual , Disfunciones Sexuales Fisiológicas/etiología , Adulto , Anciano , Imagen Corporal , Estudios Transversales , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Autoinforme , Salud Sexual , Sexualidad , Encuestas y Cuestionarios
14.
Cell Microbiol ; 18(3): 330-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26762760

RESUMEN

Invasive bacterial pathogens are engulfed upon host cell entry in a vacuolar environment called the bacteria-containing vacuole (BCV). BCVs directly contact with numerous host compartments, mainly vesicles of the endocytic pathway, such as endosomes or lysosomes. In addition, they also interact with the endoplasmic reticulum and endomembranes of the secretory pathway. These connections between the pathogen and the host occur either through heterotypic membrane fusions or through membrane contact sites. The precise regulation of BCV contacts with host compartments defines the constitution of the intracellular bacterial niche. It emerges that the associated pathways may control the stability of the BCV resulting either in vacuolar or cytoplasmically growing bacteria. Here, we will portray how the usage of novel proteomics and imaging technologies allows comparison of the communication of different host cell compartments with four relevant intracellular human pathogens, namely Salmonella enterica, Legionella pneumophila, Shigella flexneri and Francisella tularensis. The first two remain mainly within the BCV, and the latter two escape into the cytoplasm.


Asunto(s)
Interacciones Huésped-Patógeno/fisiología , Orgánulos/microbiología , Salmonella enterica/patogenicidad , Vacuolas/microbiología , Francisella tularensis/patogenicidad , Humanos , Legionella pneumophila/patogenicidad , Shigella flexneri/patogenicidad
15.
Cell Microbiol ; 17(12): 1699-720, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26084942

RESUMEN

Salmonella invades epithelial cells and survives within a membrane-bound compartment, the Salmonella-containing vacuole (SCV). We isolated and determined the host protein composition of the SCV at 30 min and 3 h of infection to identify and characterize novel regulators of intracellular bacterial localization and growth. Quantitation of the SCV protein content revealed 392 host proteins specifically enriched at SCVs, out of which 173 associated exclusively with early SCVs, 124 with maturing SCV and 95 proteins during both time-points. Vacuole interactions with endoplasmic reticulum-derived coat protein complex II vesicles modulate early steps of SCV maturation, promoting SCV rupture and bacterial hyper-replication within the host cytosol. On the other hand, SCV interactions with VAMP7-positive lysosome-like vesicles promote Salmonella-induced filament formation and bacterial growth within the late SCV. Our results reveal that the dynamic communication between the SCV and distinct host organelles affects both intracellular Salmonella localization and growth at successive steps of host cell invasion.


Asunto(s)
Vesículas Cubiertas por Proteínas de Revestimiento/metabolismo , Células Epiteliales/microbiología , Interacciones Huésped-Patógeno , Lisosomas/metabolismo , Proteínas R-SNARE/metabolismo , Salmonella typhimurium/fisiología , Vacuolas/microbiología , Células Epiteliales/fisiología , Células HeLa , Humanos , Salmonella typhimurium/crecimiento & desarrollo , Vacuolas/química
16.
Arch Psychiatr Nurs ; 30(4): 470-5, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27455920

RESUMEN

BACKGROUND: Mental health problems, particularly depression, are a major risk factor for suicide. Currently, there is no way to predict, with 100% accuracy, who will make a suicide attempt, but during a clinical interview, it is possible to assess the risk presented by each patient based on the investigation of risk and protective factors. The assessment of these factors helps health care professionals make decisions on the interventions to put into practice, thus contributing to reducing risk. The use of suicide risk assessment tools, properly validated for the population under consideration facilitate communication and information gathering, with clinical nurse specialists in mental health playing an important role. METHOD: Because of the shortage of suicide risk assessment tools properly validated for the Portuguese population, it was our aim to translate, adapt and validate the Nurses Global Assessment of Suicide Risk (NGASR) for the Portuguese population. In this study, a questionnaire was applied to a sample of 109 patients with depressive symptoms and risk factors for suicidal behaviors. RESULTS: The analysis of the results showed that most sample participants had a very high risk of suicide. The study of the psychometric properties of the NGASR showed moderate internal consistency and good content and criterion validity. Content validity, obtained through a panel of experts, was consensual. The NGASR index had good criterion validity, showing strong correlation with the SIQ, BDI and DASS-21 (R=0.830, p<0.05). The principal components analysis showed 6 factors, and the 15 predictive variables explained 66.92% of the total variance. CONCLUSION: These results are similar to those obtained in studies conducted in other countries and, therefore, the application of the NGASR is believed to be reliable for the Portuguese population.


Asunto(s)
Escalas de Valoración Psiquiátrica Breve/normas , Enfermeras Clínicas , Psicometría/estadística & datos numéricos , Suicidio/psicología , Adulto , Escalas de Valoración Psiquiátrica Breve/estadística & datos numéricos , Depresión/psicología , Femenino , Humanos , Masculino , Portugal , Reproducibilidad de los Resultados , Factores de Riesgo , Encuestas y Cuestionarios , Traducción , Prevención del Suicidio
17.
Theor Biol Med Model ; 11 Suppl 1: S6, 2014 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-25077431

RESUMEN

BACKGROUND: Social media platforms encourage people to share diverse aspects of their daily life. Among these, shared health related information might be used to infer health status and incidence rates for specific conditions or symptoms. In this work, we present an infodemiology study that evaluates the use of Twitter messages and search engine query logs to estimate and predict the incidence rate of influenza like illness in Portugal. RESULTS: Based on a manually classified dataset of 2704 tweets from Portugal, we selected a set of 650 textual features to train a Naïve Bayes classifier to identify tweets mentioning flu or flu-like illness or symptoms. We obtained a precision of 0.78 and an F-measure of 0.83, based on cross validation over the complete annotated set. Furthermore, we trained a multiple linear regression model to estimate the health-monitoring data from the Influenzanet project, using as predictors the relative frequencies obtained from the tweet classification results and from query logs, and achieved a correlation ratio of 0.89 (p<0.001). These classification and regression models were also applied to estimate the flu incidence in the following flu season, achieving a correlation of 0.72. CONCLUSIONS: Previous studies addressing the estimation of disease incidence based on user-generated content have mostly focused on the english language. Our results further validate those studies and show that by changing the initial steps of data preprocessing and feature extraction and selection, the proposed approaches can be adapted to other languages. Additionally, we investigated whether the predictive model created can be applied to data from the subsequent flu season. In this case, although the prediction result was good, an initial phase to adapt the regression model could be necessary to achieve more robust results.


Asunto(s)
Gripe Humana/epidemiología , Internet , Motor de Búsqueda , Humanos , Modelos Lineales , Portugal/epidemiología , Curva ROC , Estadística como Asunto
18.
Acute Crit Care ; 39(2): 312-320, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38863362

RESUMEN

BACKGROUND: Sleep disorders are common among patients admitted to intensive care units (ICUs). This study aimed to assess the perceptions of sleep quality, anxiety, depression, and stress reported by ICU patients and the relationships between these perceptions and patient variables. METHODS: This cross-sectional study used consecutive non-probabilistic sampling to select participants. All patients admitted for more than 72 hours of ICU hospitalization at a Portuguese hospital between March and June 2020 were asked to complete the "Richard Campbell Sleep Questionnaire" and "Anxiety, depression, and Stress Assessment Questionnaire." The resulting data were analyzed using descriptive statistics, Pearson's correlation coefficient, Student t-tests for independent samples, and analysis of variance. The significance level for rejecting the null hypothesis was set to α ≤0.05. RESULTS: A total of 52 patients admitted to the ICU for at least 72 hours was recruited. The mean age of the participants was 64 years (standard deviation, 14.6); 32 (61.5%) of the participants were male. Approximately 19% had psychiatric disorders. The prevalence of self-reported poor sleep was higher in women (t[50]=2,147, P=0.037) and in participants with psychiatric problems, although this difference was not statistically significant (t[50]=-0.777, P=0.441). Those who reported having sleep disorders before hospitalization had a worse perception of their sleep. CONCLUSIONS: Sleep quality perception was worse in female ICU patients, those with psychiatric disorders, and those with sleep alterations before hospitalization. Implementing early interventions and designing nonpharmacological techniques to improve sleep quality of ICU patients is essential.

19.
PLOS Glob Public Health ; 4(7): e0003292, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38954687

RESUMEN

BACKGROUND: Suicide is a complex public health issue. Surveillance systems play a vital role in identifying trends and epidemiologic needs, informing public health strategies, and tailoring effective context-based suicide prevention interventions. AIM: To identify and summarise the characteristics of specific surveillance systems and general health behaviour that include data onsuicide and self-harm. METHOD: A scoping review following the JBI recommendations and PRISMA-ScR guidelines identified 29 relevant studies on suicide and self-harm surveillance systems. A systematic search was performed on Cinahl, Embase, Lilacs-Latin American and Caribbean Health Sciences Literature, PubMed-US National Library of Medicine, Scopus, and Google Scholar. The eligibility criteria include papers that use qualitative, quantitative or mixed methods with no restrictions on time or language. The following papers were excluded regarding euthanasia and assisted suicide, as well as papers that did not explicitly describe suicide, self-harm, and surveillance systems. Two researchers independently screened the materials for eligibility and extracted data from the included studies. Data analysis was conducted using content analysis. RESULTS: Twenty-nine references were included, and 30 surveillance systems were identified and classified into general health behaviour surveillance (n = 15) and specific systems for suicide and self-harm (n = 15). General health behaviour systems often operate at national data collection level, collecting non-fatal data in healthcare settings, mainly emergency departments. The specific systems exhibited greater variability in terms of context, involved actors, data collection level, data collection procedures, and case classification. Limitations found by the studies pointed mostly to case definitions and data quality. Co-production, intersectoral collaboration, clear case definition criteria and data standardisation are essential to improve surveillance systems for suicide and self-harm. CONCLUSIONS: This review identified the characteristics of surveillance systems for suicide and self-harm. Monitoring and evaluation are crucial for ongoing relevance and impact on prevention efforts.

20.
Sports Med ; 54(2): 289-302, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37924459

RESUMEN

BACKGROUND: Findings from original research, systematic reviews, and meta-analyses have demonstrated the effectiveness of resistance training (RT) on markers of performance and health. However, the literature is inconsistent with regards to the dosage effects (frequency, intensity, time, type) of RT to maximize training-induced improvements. This is most likely due to moderating factors such as age, sex, and training status. Moreover, individuals with limited time to exercise or who lack motivation to perform RT are interested in the least amount of RT to improve physical fitness. OBJECTIVES: The objective of this review was to investigate and identify lower than typically recommended RT dosages (i.e., shorter durations, lower volumes, and intensity activities) that can improve fitness components such as muscle strength and endurance for sedentary individuals or beginners not meeting the minimal recommendation of exercise. METHODS: Due to the broad research question involving different RT types, cohorts, and outcome measures (i.e., high heterogeneity), a narrative review was selected instead of a systematic meta-analysis approach. RESULTS: It seems that one weekly RT session is sufficient to induce strength gains in RT beginners with < 3 sets and loads below 50% of one-repetition maximum (1RM). With regards to the number of repetitions, the literature is controversial and some authors report that repetition to failure is key to achieve optimal adaptations, while other authors report similar adaptations with fewer repetitions. Additionally, higher intensity or heavier loads tend to provide superior results. With regards to the RT type, multi-joint exercises induce similar or even larger effects than single-joint exercises. CONCLUSION: The least amount of RT that can be performed to improve physical fitness for beginners for at least the first 12 weeks is one weekly session at intensities below 50% 1RM, with < 3 sets per multi-joint exercise.


Asunto(s)
Entrenamiento de Fuerza , Humanos , Entrenamiento de Fuerza/métodos , Aptitud Física , Fuerza Muscular/fisiología , Ejercicio Físico/fisiología , Factores de Tiempo , Músculo Esquelético/fisiología
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