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1.
PLoS Genet ; 19(3): e1010636, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36857386

RESUMEN

Plants can regenerate new organs from damaged or detached tissues. In the process of de novo root regeneration (DNRR), adventitious roots are frequently formed from the wound site on a detached leaf. Salicylic acid (SA) is a key phytohormone regulating plant defenses and stress responses. The role of SA and its acting mechanisms during de novo organogenesis is still unclear. Here, we found that endogenous SA inhibited the adventitious root formation after cutting. Free SA rapidly accumulated at the wound site, which was accompanied by an activation of SA response. SA receptors NPR3 and NPR4, but not NPR1, were required for DNRR. Wounding-elevated SA compromised the expression of AUX1, and subsequent transport of auxin to the wound site. A mutation in AUX1 abolished the enhanced DNRR in low SA mutants. Our work elucidates a role of SA in regulating DNRR and suggests a potential link between biotic stress and tissue regeneration.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ácido Salicílico/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Reguladores del Crecimiento de las Plantas/metabolismo , Hojas de la Planta/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas
2.
J Infect Dis ; 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39328079

RESUMEN

Multisystem Inflammatory Syndrome in Children (MIS-C) is a rare, potentially fatal complication of SARS-CoV-2 infection. Genetic defects in inflammation-related pathways have been linked to MIS-C, but additional research is needed, especially in diverse ethnic groups. The present study aimed to identify genetic variants underlying MIS-C in Brazilian patients. Whole-exome sequencing was performed, focusing on genes involved in the host immune response to SARS-CoV-2. Functional assays assessed the impact of selected variants on NF-κB signaling. Nine rare, potentially deleterious variants were found in eight of 21 patients, located in IL17RC, IFNA10, or NLRP12 genes. Unlike the wild-type NLRP12 protein, which inhibits NF-κB activation in HEK 293T cells, the mutant NLRP12 proteins have significantly reduced inhibitory properties. In conclusion, our results indicate that rare autosomal variants in immune-related genes may underlie MIS-C, highlighting the potential role of NLRP12 in its predisposition. These findings provide new insights for the appropriate management of MIS-C.

3.
Pediatr Res ; 96(2): 319-324, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38287106

RESUMEN

BACKGROUND: Pediatric Post-COVID-Condition (PPCC) clinics treat children despite limited scientific substantiation. By exploring real-life management of children diagnosed with PPCC, the International Post-COVID-Condition in Children Collaboration (IP4C) aimed to provide guidance for future PPCC care. METHODS: We performed a cross-sectional international, multicenter study on used PPCC definitions; the organization of PPCC care programs and patients characteristics. We compared aggregated data from PPCC cohorts and identified priorities to improve PPCC care. RESULTS: Ten PPCC care programs and six COVID-19 follow-up research cohorts participated. Aggregated data from 584 PPCC patients was analyzed. The most common symptoms included fatigue (71%), headache (55%), concentration difficulties (53%), and brain fog (48%). Severe limitations in daily life were reported in 31% of patients. Most PPCC care programs organized in-person visits with multidisciplinary teams. Diagnostic testing for respiratory and cardiac morbidity was most frequently performed and seldom abnormal. Treatment was often limited to physical therapy and psychological support. CONCLUSIONS: We found substantial heterogeneity in both the diagnostics and management of PPCC, possibly explained by scarce scientific evidence and lack of standardized care. We present a list of components which future guidelines should address, and outline priorities concerning PPCC care pathways, research and international collaboration. IMPACT: Pediatric Post-COVID Condition (PPCC) Care programs have been initiated in many countries. Children with PPCC in different countries are affected by similar symptoms, limiting many to participate in daily life. There is substantial heterogeneity in diagnostic testing. Access to specific diagnostic tests is required to identify some long-term COVID-19 sequelae. Treatments provided were limited to physical therapy and psychological support. This study emphasizes the need for evidence-based diagnostics and treatment of PPCC. The International Post-COVID Collaboration for Children (IP4C) provides guidance for guideline development and introduces a framework of priorities for PPCC care and research, to improve PPCC outcomes.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , COVID-19/terapia , Niño , Estudios Transversales , Femenino , Adolescente , Masculino , Preescolar , SARS-CoV-2 , Síndrome Post Agudo de COVID-19 , Lactante
4.
J Nat Prod ; 87(3): 480-490, 2024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38408354

RESUMEN

Scorpion venoms are a rich source of bioactive peptides, most of which are neurotoxic, with 30 to 70 amino acid residues in their sequences. There are a scarcity of reports in the literature concerning the short linear peptides found in scorpion venoms. This type of peptide toxin may be selectively extracted from the venom using 50% (v/v) acetonitrile. The use of LC-MS and MS/MS enabled the detection of 12 bioactive short linear peptides, of which six were identified as cryptides. These peptides were shown to be multifunctional, causing hemolysis, mast cell degranulation and lysis, edema, pain, and anxiety, increasing the complexity of the envenomation mechanism. Apparently, the natural functions of these peptide toxins are to induce inflammation and discomfort in the victims of scorpion stings.


Asunto(s)
Animales Ponzoñosos , Venenos de Escorpión , Escorpiones , Animales , Escorpiones/química , Brasil , Espectrometría de Masas en Tándem , Péptidos/metabolismo , Venenos de Escorpión/química
5.
Eur J Appl Physiol ; 124(9): 2749-2762, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38653795

RESUMEN

PURPOSE: Resistance training (RT) induces muscle growth at varying rates across RT phases, and evidence suggests that the muscle-molecular responses to training bouts become refined or attenuated in the trained state. This study examined how proteolysis-related biomarkers and extracellular matrix (ECM) remodeling factors respond to a bout of RT in the untrained (UT) and trained (T) state. METHODS: Participants (19 women and 19 men) underwent 10 weeks of RT. Biopsies of vastus lateralis were collected before and after (24 h) the first (UT) and last (T) sessions. Vastus lateralis cross-sectional area (CSA) was assessed before and after the experimental period. RESULTS: There were increases in muscle and type II fiber CSAs. In both the UT and T states, calpain activity was upregulated and calpain-1/-2 protein expression was downregulated from Pre to 24 h. Calpain-2 was higher in the T state. Proteasome activity and 20S proteasome protein expression were upregulated from Pre to 24 h in both the UT and T. However, proteasome activity levels were lower in the T state. The expression of poly-ubiquitinated proteins was unchanged. MMP activity was downregulated, and MMP-9 protein expression was elevated from Pre to 24 h in UT and T. Although MMP-14 protein expression was acutely unchanged, this marker was lower in T state. TIMP-1 protein levels were reduced Pre to 24 h in UT and T, while TIMP-2 protein levels were unchanged. CONCLUSION: Our results are the first to show that RT does not attenuate the acute-induced response of proteolysis and ECM remodeling-related biomarkers.


Asunto(s)
Biomarcadores , Matriz Extracelular , Proteolisis , Entrenamiento de Fuerza , Humanos , Masculino , Femenino , Entrenamiento de Fuerza/métodos , Matriz Extracelular/metabolismo , Biomarcadores/metabolismo , Adulto , Calpaína/metabolismo , Músculo Esquelético/metabolismo , Adulto Joven , Complejo de la Endopetidasa Proteasomal/metabolismo
6.
Int J Sports Med ; 45(7): 504-510, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38286426

RESUMEN

The aim of this study was to compare the effects of progressive overload in resistance training on muscle strength and cross-sectional area (CSA) by specifically comparing the impact of increasing load (LOADprog) versus an increase in repetitions (REPSprog). We used a within-subject experimental design in which 39 previously untrained young persons (20 men and 19 women) had their legs randomized to LOADprog and REPSprog. Outcomes were assessed before and after 10 weeks of training. Muscle strength was assessed using the one repetition maximum (1RM) test on the leg extension exercise, and the CSA of the vastus lateralis was assessed by ultrasonography. Both protocols increased 1RM values from pre (LOADprog: 52.90±16.32 kg; REPSprog: 51.67±15.84 kg) to post (LOADprog: 69.05±18.55 kg, REPSprog: 66.82±17.95 kg), with no difference between them (P+>+0.05). Similarly, both protocols also increased in CSA values from pre (LOADprog: 21.34±4.71 cm²; REPSprog: 21.08±4.62 cm²) to post (LOADprog: 23.53±5.41 cm², REPSprog: 23.39±5.19 cm²), with no difference between them (P+>+0.05). In conclusion, our findings indicate that the progression of overload through load or repetitions can be used to promote gains in strength and muscle hypertrophy in young men and women in the early stages of training.


Asunto(s)
Fuerza Muscular , Entrenamiento de Fuerza , Ultrasonografía , Humanos , Entrenamiento de Fuerza/métodos , Fuerza Muscular/fisiología , Masculino , Femenino , Adulto Joven , Músculo Cuádriceps/fisiología , Músculo Cuádriceps/diagnóstico por imagen , Músculo Cuádriceps/anatomía & histología , Músculo Esquelético/fisiología , Músculo Esquelético/diagnóstico por imagen , Adulto
7.
Ann Allergy Asthma Immunol ; 130(2): 225-232, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36191849

RESUMEN

BACKGROUND: Lupin is a protein-rich legume with a growing presence in the food market worldwide. With increased consumption, lupin allergy (LA) reports are also rising. Uncertainties exist on the cross-reactivity between peanut and lupin, the allergenic potential of different lupin species, and sensitization patterns among different populations. OBJECTIVE: To evaluate the molecular basis of LA and to determine lupin allergens from 3 different species that may be involved in peanut allergy (PA) cross-reactivity. METHODS: A total of 43 subjects with PA, those with LA, or controls without food allergy were evaluated with skin prick tests (SPTs) and specific IgEs (sIgEs). Lupin-sensitized subjects were offered a lupin oral food challenge (OFC). Immunoblots and enzyme-linked immunosorbent assays were performed on sera from lupin-sensitized subjects. RESULTS: In this study, 44% of the PA subjects were confirmed to have LA by OFC. Anaphylaxis was the most frequent manifestation after lupin consumption, with a minimal eliciting dosage of 1 g lupin flour. There was no difference in lupin sIgE or SPT wheal size between lupin-sensitized and confirmed LA subjects or in the severity of symptoms among confirmed LA subjects. Sera from lupin-sensitized subjects uniformly reacted to all 3 different lupin species. Immunoblotting and enzyme-linked immunosorbent assays revealed immunoglobulin E binding to α- and γ-conglutin in all analyzed sera, whereas α- and ß-conglutin recognition was variable. CONCLUSION: Our findings reveal a high prevalence of LA among PA subjects, emphasizing lupin must be labeled as an allergen in foods. Owing to high variability in lupin-sIgE and lupin-SPT results, LA diagnosis may require OFC. In our population, γ-conglutin is the major allergen of lupin.


Asunto(s)
Hipersensibilidad a los Alimentos , Lupinus , Hipersensibilidad al Cacahuete , Humanos , Hipersensibilidad al Cacahuete/diagnóstico , Hipersensibilidad al Cacahuete/epidemiología , Alérgenos , Prevalencia , Inmunoglobulina E , Lupinus/efectos adversos , Arachis , Pruebas Cutáneas/métodos
8.
J Nat Prod ; 85(9): 2127-2134, 2022 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-36044031

RESUMEN

Cyclotides are mini-proteins with potent bioactivities and outstanding potential for agricultural and pharmaceutical applications. More than 450 different plant cyclotides have been isolated from six angiosperm families. In Brazil, studies involving this class of natural products are still scarce, despite its rich floristic diversity. Herein were investigated the cyclotides from Anchietea pyrifolia roots, a South American medicinal plant from the family Violaceae. Fourteen putative cyclotides were annotated by LC-MS. Among these, three new bracelet cyclotides, anpy A-C, and the known cycloviolacins O4 (cyO4) and O17 (cyO17) were sequenced through a combination of chemical and enzymatic reactions followed by MALDI-MS/MS analysis. Their cytotoxic activity was evaluated by a cytotoxicity assay against three human cancer cell lines (colorectal carcinoma cells: HCT 116 and HCT 116 TP53-/- and breast adenocarcinoma, MCF 7). For all assays, the IC50 values of isolated compounds ranged between 0.8 and 7.3 µM. CyO17 was the most potent cyclotide for the colorectal cancer cell lines (IC50, 0.8 and 1.2 µM). Furthermore, the hemolytic activity of anpy A and B, cyO4, and cyO17 was assessed, and the cycloviolacins were the least hemolytic (HD50 > 156 µM). This work sheds light on the cytotoxic effects of the anpy cyclotides against cancer cells. Moreover, this study expands the number of cyclotides obtained to date from Brazilian plant biodiversity and adds one more genus containing these molecules to the list of the Violaceae family.


Asunto(s)
Productos Biológicos , Ciclotidas , Proteínas de Plantas , Violaceae , Productos Biológicos/química , Productos Biológicos/aislamiento & purificación , Productos Biológicos/farmacología , Brasil , Línea Celular Tumoral , Ciclotidas/química , Ciclotidas/aislamiento & purificación , Ciclotidas/farmacología , Humanos , Proteínas de Plantas/química , Proteínas de Plantas/aislamiento & purificación , Proteínas de Plantas/farmacología , Espectrometría de Masas en Tándem , Violaceae/química
9.
Eur J Appl Physiol ; 120(10): 2223-2232, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32700098

RESUMEN

PURPOSE: We compared the effects of suspension training (ST) with traditional resistance training (TRT) on muscle mass, strength and functional performance in older adults. METHODS: Forty-two untrained older adults were randomized in TRT, ST (both performed 3 sets of whole body exercises to muscle failure) or control group (CON). Muscle thickness (MT) of biceps brachii (MTBB) and vastus lateralis (MTVL), maximal dynamic strength test (1RM) for biceps curl (1RMBC) and leg extension exercises (1RMLE), and functional performance tests (chair stand [CS], timed up and go [TUG] and maximal gait speed [MGS]) were performed before and after 12 weeks of training. RESULTS: MTBB increased significantly and similarly for all training groups (TRT 23.35%; ST 21.56%). MTVL increased significantly and similarly for all training groups (TRT 13.03%; ST 14.07%). 1RMBC increased significantly and similarly for all training groups (TRT 16.06%; ST 14.33%). 1RMLE increased significantly and similarly for all training groups (TRT 14.89%; ST 18.06%). MGS increased significantly and similarly for all groups (TRT 6.26%; ST 5.99%; CON 2.87%). CS decreased significantly and similarly for all training groups (TRT - 20.80%; ST - 15.73%). TUG decreased significantly and similarly for all training groups (TRT - 8.66%; ST - 9.16%). CONCLUSION: Suspension training (ST) promotes similar muscle mass, strength and functional performance improvements compared to TRT in older adults.


Asunto(s)
Fuerza Muscular , Músculo Esquelético/fisiología , Entrenamiento de Fuerza/métodos , Anciano , Femenino , Marcha , Humanos , Pierna/fisiología , Masculino , Persona de Mediana Edad , Contracción Muscular , Músculo Esquelético/crecimiento & desarrollo , Entrenamiento de Fuerza/efectos adversos
11.
Genome ; 61(12): 857-865, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30427722

RESUMEN

PLAC8 is a cysteine-rich protein described as a central mediator of tumor evolution in mammals; as such, it represents a promising candidate for diagnostic and therapeutic targeting. The human PLAC8 gene is also involved in contact hypersensitivity response and presents a role in psoriatic skin. In plants, PLAC8 motif-containing proteins are involved in the determination of organ size and growth, response to infection, Ca2+ influx, Cd resistance, and zinc detoxification. In general, PLAC8 motif-containing proteins present the conserved CCXXXXCPC or CLXXXXCPC region. However, there is no devised nomenclature for the PLAC8 motif-containing proteins. Here, through the analysis of 445 sequences, we show that PLAC8 motif-containing proteins constitute a unique gene family, and we propose a unified nomenclature. This is the first report indicating the existence of different groups of PLAC8 proteins, which we have called types I, II, and III. Type I genes are found in mammals, fungi, plants, and algae, and types II and III are exclusive to plants. Our study describes for the first time PLAC8 type III proteins. Whether these sequences maintain their known functional role or possess distinct functions of types I and II genes remains unclear.


Asunto(s)
Familia de Multigenes , Proteínas de Plantas/genética , Proteínas/genética , Terminología como Asunto , Animales , Apoptosis , Diferenciación Celular , Proliferación Celular , Humanos , Mamíferos/genética , Proteínas de Plantas/clasificación , Proteínas de Plantas/fisiología , Proteínas/clasificación , Proteínas/fisiología
12.
Biochim Biophys Acta ; 1840(1): 170-83, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24007897

RESUMEN

BACKGROUND: The peptide Paulistine was isolated from the venom of wasp Polybia paulista. This peptide exists under a natural equilibrium between the forms: oxidised - with an intra-molecular disulphide bridge; and reduced - in which the thiol groups of the cysteine residues do not form the disulphide bridge. The biological activities of both forms of the peptide are unknown up to now. METHODS: Both forms of Paulistine were synthesised and the thiol groups of the reduced form were protected with the acetamidemethyl group [Acm-Paulistine] to prevent re-oxidation. The structure/activity relationships of the two forms were investigated, taking into account the importance of the disulphide bridge. RESULTS: Paulistine has a more compact structure, while Acm-Paulistine has a more expanded conformation. Bioassays reported that Paulistine caused hyperalgesia by interacting with the receptors of lipid mediators involved in the cyclooxygenase type II pathway, while Acm-Paullistine also caused hyperalgesia, but mediated by receptors involved in the participation of prostanoids in the cyclooxygenase type II pathway. CONCLUSION: The acetamidemethylation of the thiol groups of cysteine residues caused small structural changes, which in turn may have affected some physicochemical properties of the Paulistine. Thus, the dissociation of the hyperalgesy from the edematogenic effect when the actions of Paulistine and Acm-Paulistine are compared to each other may be resulting from the influence of the introduction of Acm-group in the structure of Paulistine. GENERAL SIGNIFICANCE: The peptides Paulistine and Acm-Paulistine may be used as interesting tools to investigate the mechanisms of pain and inflammation in future studies.


Asunto(s)
Antibacterianos/farmacología , Quimiotaxis/efectos de los fármacos , Edema/tratamiento farmacológico , Hiperalgesia/tratamiento farmacológico , Mastocitos/efectos de los fármacos , Fragmentos de Péptidos/química , Venenos de Avispas/farmacología , Animales , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Células Cultivadas , Dicroismo Circular , Edema/metabolismo , Hemólisis/efectos de los fármacos , Hiperalgesia/metabolismo , Masculino , Mastocitos/citología , Mastocitos/metabolismo , Ratones , Modelos Moleculares , Simulación de Dinámica Molecular , Oxidación-Reducción , Fragmentos de Péptidos/farmacología , Ratas , Receptores de Leucotrienos/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Relación Estructura-Actividad , Avispas/química , Avispas/crecimiento & desarrollo
13.
Biochim Biophys Acta ; 1838(10): 2357-68, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24955498

RESUMEN

Polycationic peptides may present their C-termini in either amidated or acidic form; however, the effects of these conformations on the mechanisms of interaction with the membranes in general were not properly investigated up to now. Protonectarina-MP mastoparan with an either amidated or acidic C-terminus was utilized to study their interactions with anionic and zwitterionic vesicles, using measurements of dye leakage and a combination of H/D exchange and mass spectrometry to monitor peptide-membrane interactions. Mast cell degranulation, hemolysis and antibiosis assays were also performed using these peptides, and the results were correlated with the structural properties of the peptides. The C-terminal amidation promotes the stabilization of the secondary structure of the peptide, with a relatively high content of helical conformations, permitting a deeper interaction with the phospholipid constituents of animal and bacterial cell membranes. The results suggested that at low concentrations Protonectarina-MP interacts with the membranes in a way that both terminal regions remain positioned outside the external surface of the membrane, while the α-carbon backbone becomes partially embedded in the membrane core and changing constantly the conformation, and causing membrane destabilization. The amidation of the C-terminal residue appears to be responsible for the stabilization of the peptide conformation in a secondary structure that is richer in α-helix content than its acidic congener. The helical, amphipathic conformation, in turn, allows a deeper peptide-membrane interaction, favoring both biological activities that depend on peptide structure recognition by the GPCRs (such as exocytosis) and those activities dependent on membrane perturbation (such as hemolysis and antibiosis).


Asunto(s)
Degranulación de la Célula/efectos de los fármacos , Membrana Celular , Mastocitos/metabolismo , Membranas Artificiales , Péptidos , Venenos de Avispas , Animales , Membrana Celular/química , Membrana Celular/metabolismo , Femenino , Péptidos y Proteínas de Señalización Intercelular , Mastocitos/citología , Péptidos/química , Péptidos/farmacología , Estructura Secundaria de Proteína , Ratas , Ratas Wistar , Venenos de Avispas/química , Venenos de Avispas/farmacología
14.
Funct Integr Genomics ; 15(6): 639-49, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26277721

RESUMEN

Programmed cell death (PCD) is an ordered cell suicide that removes unwanted or damaged cells, playing a role in defense to environmental stresses and pathogen invasion. PCD is component of the life cycle of plants, occurring throughout development from embryogenesis to the death. Metacaspases are cysteine proteases present in plants, fungi, and protists. In certain plant-pathogen interactions, the PCD seems to be mediated by metacaspases. We adopted a comparative genomic approach to identify genes coding for the metacaspases in Viridiplantae. We observed that the metacaspase was divided into types I and II, based on their protein structure. The type I has a metacaspase domain at the C-terminus region, presenting or not a zinc finger motif in the N-terminus region and a prodomain rich in proline. Metacaspase type II does not feature the prodomain and the zinc finger, but has a linker between caspase-like catalytic domains of 20 kDa (p20) and 10 kDa (p10). A high conservation was observed in the zinc finger domain (type I proteins) and in p20 and p10 subunits (types I and II proteins). The phylogeny showed that the metacaspases are divided into three principal groups: type I with and without zinc finger domain and type II metacaspases. The algae and moss are presented as outgroup, suggesting that these three classes of metacaspases originated in the early stages of Viridiplantae, being the absence of the zinc finger domain the ancient condition. The study of metacaspase can clarify their assignment and involvement in plant PCD mechanisms.


Asunto(s)
Caspasas/metabolismo , Familia de Multigenes , Proteínas de Plantas/metabolismo , Plantas/enzimología , Estrés Fisiológico , Secuencia de Aminoácidos , Apoptosis , Secuencia de Bases , Caspasas/genética , Datos de Secuencia Molecular , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas/genética , Plantas/metabolismo
15.
Microbiol Res ; 281: 127606, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38277718

RESUMEN

The present study explores the potential of rhizobacteria isolated from Baccharis linearis and Solidago chilensis in metal(loid)-contaminated soil for producing N-acyl-homoserine lactones (AHLs)-type signal molecules and promoting plant growth. A total of 42 strains were isolated, four demonstrating the production of AHL-type signal molecules. Based on 16S rRNA gene sequencing analyses and MALDI-TOF analyses, these four isolates were identified as belonging to the Pseudomonas genus, specifically P. brassicacearum, P. frederickberguensis, P. koreensis, and P. orientalis. The four AHL-producing strains were evaluated for metal(loid)s tolerance, their plant growth promotion traits, AHL quantification, and their impact on in vitro Lactuca sativa plant growth. The study found that four strains exhibited high tolerance to metal(loid)s, particularly As, Cu, and Zn. Additionally, plant growth-promoting traits were detected in AHL-producing bacteria, such as siderophore production, ammonia production, ACC deaminase activity, and P solubilization. Notably, AHL production varied among strains isolated from B. linearis, where C7-HSL and C9-HSL signal molecules were detected, and S. chilensis, where only C7-HSL signal molecules were observed. In the presence of copper, the production of C7-HSL and C9-HSL significantly decreased in B. linearis isolates, while in S. chilensis isolates, C7-HSL production was inhibited. Further, when these strains were inoculated on lettuce seeds and in vitro plants, a significant increase in germination and plant growth was observed. Mainly, the inoculation of P. brassicacearum and P. frederickberguensis led to extensive root hair development, significantly increasing length and root dry weight. Our results demonstrate that rhizospheric strains produce AHL molecules and stimulate plant growth, primarily through root development. However, the presence of copper reduces the production of these molecules, potentially affecting the root development of non-metalloid tolerant plants such as S. chilensis, which would explain its low population in this hostile environment.


Asunto(s)
Acil-Butirolactonas , Percepción de Quorum , Percepción de Quorum/genética , Cobre , ARN Ribosómico 16S/genética , Plantas/genética , Suelo
16.
Artículo en Inglés | MEDLINE | ID: mdl-39303293

RESUMEN

This study investigated the impact of menstrual cycle (MC) phases and resistance training (RT) on muscle cross-sectional area (CSA) in two MCs utilizing a within-subject design. Twenty women with regular MCs had their legs randomly allocated to either the control (CON) or RT condition, which included 16 training sessions over two MCs. CSA, estradiol (E2), and progesterone (P4) were assessed during the menstruation (M), ovulation (O), and luteal (L) phases in the first (M1, O1, L1) and second (M2, O2, L2) MCs and at the beginning of the third MC (M3). P4 values were significantly higher during the luteal phase than during menstruation (P < 0.0001) and ovulation (P < 0.0001). No significant differences in E2 concentrations were observed between the MC phases (P = 0.08). For the RT condition, the CSA showed significant increases at O2, L2, and M3 compared to baseline (M1) (all P < 0.0001). No significant changes were observed for the CON condition during the two MCs (P > 0.05). However, RT condition showed a significant change in average CSA across two MCs. Additionally, individual analyses revealed that 19 participants showed variation in CSA above or below the minimum detectable difference during the two MCs. These findings suggest that changes in muscle CSA observed during two MCs may not be exclusively attributed to RT.

17.
Med Sci Sports Exerc ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38934511

RESUMEN

PURPOSE: Androgen receptor (AR) expression and signaling has been regarded as a mechanism for regulating muscle hypertrophy. However, little is known about the associations between acute and chronic changes in skeletal muscle total AR, cytoplasmic AR (cAR), nuclear AR (nAR) and AR DNA-binding (AR-DNA) induced by resistance training (RT) and hypertrophy outcomes in women and men. This study aimed to investigate the acute and chronic effects of RT on skeletal muscle total AR, cAR, nAR contents and AR-DNA in women and men. Additionally, we investigated whether these acute and chronic changes in these markers were associated with muscle hypertrophy in both sexes. METHODS: Nineteen women and 19 men underwent 10 weeks of RT. Muscle biopsies were performed at baseline, 24 h after the first RT session and 96-120 h after the last session. AR, cAR and nAR were analyzed using Western blotting, and AR-DNA using an ELISA-oligonucleotide assay. Fiber cross-sectional area (fCSA) was analyzed through immunohistochemistry and muscle cross-sectional area (mCSA) by ultrasound. RESULTS: At baseline, men demonstrated greater nAR than women. Baseline cAR was significantly associated with type II fCSA hypertrophy in men. Acutely, both sexes decreased AR and cAR, whereas men demonstrated greater decreases in nAR. After 10 weeks of RT, AR and nAR remained unchanged, men demonstrated greater cAR compared to women, and both sexes decreased AR-DNA activity. Acute and chronic changes in AR markers did not correlate with muscle hypertrophy (type I/II fCSA and mCSA) in women or men. CONCLUSIONS: Baseline cAR content may influence hypertrophy in men, while neither RT-induced acute nor chronic changes in AR, cAR, nAR, and AR-DNA are associated with muscle hypertrophy in women or men.

18.
J Appl Physiol (1985) ; 137(4): 910-918, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39143904

RESUMEN

The aim of this study was to investigate whether baseline values and acute and chronic changes in androgen receptors (AR) markers, including total AR, cytoplasmic (cAR), and nuclear (nAR) fractions, as well as DNA-binding activity (AR-DNA), are involved in muscle hypertrophy responsiveness by comparing young nonresponder and responder individuals. After 10 wk of resistance training (RT), participants were identified as nonresponders using two typical errors (TE) obtained through two muscle cross-sectional area (mCSA) ultrasound measurements (2 × TE; 4.94%), and the highest responders within our sample were numerically matched. Muscle biopsies were performed at baseline, 24 h after the first RT session (acute responses), and 96 h after the last session (chronic responses). AR, cAR, and nAR were analyzed using Western blotting, and AR-DNA was analyzed using an ELISA-oligonucleotide assay. Twelve participants were identified as nonresponders (ΔmCSA: -1.32%) and 12 as responders (ΔmCSA: 21.35%). There were no baseline differences between groups in mCSA, AR, cAR, nAR, or AR-DNA (P > 0.05). For acute responses, there was a significant difference between nonresponders (+19.5%) and responders (-14.4%) in AR-DNA [effect size (ES) = -1.39; 95% confidence interval (CI): -2.53 to -0.16; P = 0.015]. There were no acute between-group differences in any other AR markers (P > 0.05). No significant differences between groups were observed in chronic responses across any AR markers (P > 0.05). Nonresponders and responders presented similar baseline, acute, and chronic results for the majority of the AR markers. Thus, our findings do not support the influence of AR markers on muscle hypertrophy responsiveness to RT in untrained individuals.NEW & NOTEWORTHY We explored, for the first time, the influence of androgen receptor (AR) through the separation of cytoplasmic and nuclear cell fractions [i.e., cytoplasmic androgen receptor (cAR), nuclear androgen receptor (nAR), and androgen receptor DNA-binding activity (AR-DNA)] on muscle hypertrophy responsiveness to resistance training. The absence of muscle hypertrophy in naïve individuals does not seem to be explained by baseline values, and acute or chronic changes in AR markers.


Asunto(s)
Hipertrofia , Músculo Esquelético , Receptores Androgénicos , Entrenamiento de Fuerza , Humanos , Entrenamiento de Fuerza/métodos , Receptores Androgénicos/metabolismo , Masculino , Músculo Esquelético/metabolismo , Adulto Joven , Adulto , Biomarcadores/metabolismo , Femenino
19.
J Ultrasound ; 26(4): 871-877, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37603258

RESUMEN

OBJECTIVES: To assess whether there is an association between abnormal common femoral vein (CFV) Doppler waveform and intensive care unit (ICU) mortality in patients with sepsis. METHODS: Patients admitted to the ICU with sepsis were included. Pulsed-wave Doppler was performed by examining the CFV in the short axis without angle correction and in the long axis with angle correction. An abnormal CFV Doppler waveform was determined by a retrograde velocity peak (RVP) > 10 cm/s in the long axis or RVP > 50% of the antegrade velocity peak in the short axis. TAPSE < 17 mm was defined as right ventricular (RV) dysfunction. The primary outcome was ICU mortality. RESULTS: One hundred and ten patients were included. There was no association between abnormal CFV Doppler waveforms in the long (p = 0.709) and short axes (p = 0.171) and ICU mortality. TAPSE measurements were performed in 16 patients. RV dysfunction was identified in 8 (50.0%) patients. There was no association between the diagnosis of RV dysfunction based on TAPSE measurement and the identification of abnormal CFV Doppler waveforms in the long axis (p = 1.000) and in the short axis (p = 1.000). CONCLUSION: Abnormal CFV Doppler waveforms were not associated with ICU mortality in patients with sepsis. Furthermore, in the exploratory analysis, these alterations were not useful in identifying RV dysfunction in these patients.


Asunto(s)
Vena Femoral , Sepsis , Humanos , Pronóstico , Vena Femoral/diagnóstico por imagen , Estudios Prospectivos , Ultrasonografía Doppler , Sepsis/diagnóstico por imagen
20.
Microorganisms ; 11(8)2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37630439

RESUMEN

Zea mays var. amylacea and Zea mays var. indurata are maize ecotypes from Paraguay. Aspergillus section Flavi is the main spoilage fungus of maize under storage conditions. Due to its large intraspecific genetic variability, the accurate identification of this fungal taxonomic group is difficult. In the present study, potential mycotoxigenic strains of Aspergillus section Flavi isolated from Z. mays var. indurata and Z. mays var. amylacea that are marketed in the metropolitan region of Asunción were identified by a polyphasic approach. Based on morphological characters, 211 isolates were confirmed to belong to Aspergillus section Flavi. A subset of 92 strains was identified as Aspergillus flavus by mass spectrometry MALDI-TOF and the strains were classified by MALDI-TOF MS into chemotypes based on their aflatoxins and cyclopiazonic acid production. According to the partial sequencing of ITS and CaM genes, a representative subset of 38 A. flavus strains was confirmed. Overall, 75 A. flavus strains (86%) were characterized as producers of aflatoxins. The co-occurrence of at least two mycotoxins (AF/ZEA, FUM/ZEA, and AF/ZEA/FUM) was detected for five of the Z. mays samples (63%). Considering the high mycological bioburden and mycotoxin contamination, maize marketed in the metropolitan region of Asunción constitutes a potential risk to food safety and public health and requires control measures.

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