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1.
Animals (Basel) ; 14(2)2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38254422

RESUMO

Cryopreservation is a widely used method of semen conservation in animal breeding programs. This process, however, can have a detrimental effect on sperm quality, especially in terms of its morphology. The resultant sperm disorders raise the risk of reduced sperm fertilizing ability, which poses a serious threat to the long-term efficacy of livestock reproduction and breeding. Understanding the genetic factors underlying these effects is critical for maintaining sperm quality during cryopreservation, and for animal fertility in general. In this regard, we performed a genome-wide association study to identify genomic regions associated with various cryopreservation sperm abnormalities in Holstein cattle, using single nucleotide polymorphism (SNP) markers via a high-density genotyping assay. Our analysis revealed a significant association of specific SNPs and candidate genes with absence of acrosomes, damaged cell necks and tails, as well as wrinkled acrosomes and decreased motility of cryopreserved sperm. As a result, we identified candidate genes such as POU6F2, LPCAT4, DPYD, SLC39A12 and CACNB2, as well as microRNAs (bta-mir-137 and bta-mir-2420) that may play a critical role in sperm morphology and disorders. These findings provide crucial information on the molecular mechanisms underlying acrosome integrity, motility, head abnormalities and damaged cell necks and tails of sperm after cryopreservation. Further studies with larger sample sizes, genome-wide coverage and functional validation are needed to explore causal variants in more detail, thereby elucidating the mechanisms mediating these effects. Overall, our results contribute to the understanding of genetic architecture in cryopreserved semen quality and disorders in bulls, laying the foundation for improved animal reproduction and breeding.

2.
J Matern Fetal Neonatal Med ; 36(2): 2290919, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38073078

RESUMO

BACKGROUND: Energy metabolism mediators, which include the adipokines (leptin, adiponectin, ghrelin) and insulin-like growth factor 1 [IGF-1], are hormone-like proteins, produced and expressed in the placenta and fetal membranes, with properties featuring metabolic adaptation and inflammatory processes. Due to the complexity of the metabolic adaptation of preterm neonates during the transition to extrauterine life, it becomes essential to recognize the factors that influence the alteration of the adipokines and IGF-1 levels in the early postpartum stage.This study assessed the significance of maternal-fetal-neonatal factors in predicting the levels of leptin, adiponectin, ghrelin, and IGF-1 in preterm infants born at 32 or fewer weeks of gestation, during the early stage of postnatal adaptation. METHODS: Energy metabolism mediator levels were measured in urine samples obtained from extremely (less than 28 weeks) and very (28-32 weeks) preterm infants, within 48 h after their birth, and before the initiation of enteral nutrition. The urine samples were analyzed using enzyme-linked immunosorbent assay (ELISA) kits. The collected data included all birth-related maternal and neonatal factors such as maternal age, race/ethnicity, hypertensive disorders of pregnancy, diabetes, gravidity, parity, type of pregnancy, mode of delivery, and antenatal use of corticosteroids, antibiotics, magnesium sulfate, Apgar scores at 1 and 5 min, gestational age, and birth weight. We investigated the correlation between the levels of the tested mediators, the significance of the differences in their average levels based on the dichotomized maternal and neonatal factors, and the effect of the selected factors, in multiple regression models. Data from the regression models constructed for leptin, adiponectin, ghrelin, and IGF-1 are presented as regression coefficient ß with Standard Error (SE) of ß, coefficient of determination (R2), and adjusted R2. Before including the factor in regression models, we tested for the multicollinearity effect. Two-sided P values <0.05 were considered statistically significant. RESULTS: Among the 70 studied infants, 47.1% were male, 40.6% were white, 28.6% were extremely preterm, and 18.6% were born with a weight <750 grams. Except for a mild interplay between the adiponectin and IGF-1 levels, there was no correlation between the levels of the other studied mediators. Up to 20% variation in the tested energy metabolism mediator levels was dependent on some of the birth-related maternal and neonatal characteristics. For instance, leptin levels were reduced in association with male gender (-0.493 [0.190], p < 0.02) and increased in infants born to primigravids (0.562 [0.215], p < 0.02). Adiponectin levels were increased in infants born to nulliparous as compared to multiparous women (0.400 [0.171], p < 0.03). Ghrelin levels were reduced in males (-0.057 [0.026], p < 0.04). IGF-1 levels were increased in the urine of extremely preterm neonates (0.357 [0.111], p < 0.01) and preterm infants born with an Apgar less than three at 1 min (0. 340 [p < 0.153], p < 0.04). CONCLUSIONS: Nearly one-fifth of the variation in the urinary levels of the adipokines (leptin, adiponectin, ghrelin) and IGF-1 during the early postnatal stage in infants born at 32 or fewer weeks of gestation was predicated on one or more of the maternal and neonatal factors such as the infant's sex, extreme preterm gestation, a low Apgar score at 1 min, or birth to nulliparous women or primigravida mothers. Further studies will be required to explain the role of energy metabolism mediators in the postnatal adaptation of preterm-born infants.


Assuntos
Recém-Nascido Prematuro , Leptina , Lactente , Recém-Nascido , Humanos , Masculino , Feminino , Gravidez , Grelina , Fator de Crescimento Insulin-Like I , Adiponectina , Idade Gestacional , Metabolismo Energético
3.
Gels ; 9(12)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38131940

RESUMO

OBJECTIVES: The use of non-adhesive gel-like embolic materials (NAGLEMs) in the endovascular treatment of hypervascularized formations in the head and neck is gaining in popularity because of a number of important characteristics involved. Their primary benefits are their capacity to penetrate diseased vasculature, effectively distribute, and, most importantly, remain controllable during the process. We reviewed the literature and evaluated the results of using NAGLEMs in comparison to other embolizing substances (namely, coils, glue, and particles) as alternative embolizing agents for patients receiving care at our clinic. The process comprised evaluating the safety, effectiveness, and technological elements of endovascular therapy used to treat two categories of hypervascular pathological abnormalities that were surgically corrected between 2015 and 2023. Arteriovenous malformations (AVMs) located in the head, neck, and paragangliomas with jugular/carotid body localization are combined by intense shunting blood flow and shared requirements for the embolic agent used in endovascular treatment (such as penetration, distribution, delayed polymerization, and controllability). An analysis of the literature was also conducted. Results showed 18 patients diagnosed with neck paragangliomas of the carotid body and jugular type. Five patients with arteriovenous malformation (AVM) of the face and neck were included, consisting of sixteen females and seven males with an average age of 55 ± 13 years. Endovascular procedures were performed using NAGLEMs (ONYX (Medtronic, Irvine, CA, USA), SQUID (Balt, Montmorency, France), and PHIL (Microvention, Tustin, CA, USA)) and dimethyl sulfoxide (DMSO)-compatible balloon catheters. All patients achieved complete or partial embolization of hypervascularized formations using one or more stages of endovascular treatment. Additionally, three AVMs of the face and two paragangliomas of the neck were surgically excised following embolization. In other instances, formations were not deemed necessary to be removed. The patients' condition upon discharge was assessed by the modified Rankin Scale (mRs) and rated between 0 and 2. CONCLUSION: Currently, NAGLEMs are predominantly used to treat hypervascularized formations in the neck and head due to their fundamental properties. These properties include a lack of adhesion and a delay in predictable polymerization (after 30-40 min). NAGLEMs also exhibit excellent distribution and penetration throughout the vascular bed of the formation. Adequate controllability of the process is largely achieved through the presence of embolism forms of different viscosity, as well as excellent X-ray visualization.

4.
Int J Mol Sci ; 24(24)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38139081

RESUMO

The cellulose-enriched tertiary cell walls present in many plant fibers have specific composition, architecture, machinery of formation, and function. To better understand the mechanisms underlying their mode of action and to reveal the peculiarities of fibers from different plant species, it is necessary to more deeply characterize the major components. Next to overwhelming cellulose, rhamnogalacturonan I (RG-I) is considered to be the key polymer of the tertiary cell wall; however, it has been isolated and biochemically characterized in very few plant species. Here, we add RG-I to the list from the phloem fibers of the Phaseolus vulgaris stem that was isolated and analyzed by nuclear magnetic resonance (NMR), dynamic light scattering, and immunolabeling, both within tissue and as an isolated polymer. Additionally, fibers with tertiary cell walls from nine species of dicotyledonous plants from the orders Malphigiales, Fabales, and Rosales were labeled with RG-I-related antibodies to check the presence of the polymer and compare the in situ presentation of its backbone and side chains. The obtained results confirm that RG-I is an obligatory polymer of the tertiary cell wall. However, there are differences in the structure of this polymer from various plant sources, and these peculiarities may be taxonomically related.


Assuntos
Galactanos , Pectinas , Galactanos/química , Pectinas/química , Plantas , Celulose , Parede Celular/química
5.
Toxics ; 11(12)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38133358

RESUMO

The possibility of plants growing on serpentine soils and the ability of serpentine minerals to accumulate significant amounts of metals was the basis for developing a method for using serpentine-containing materials to restore vegetation in areas with a high level of metal pollution. Serpentine-containing products obtained from phlogopite mining overburden (Kovdor, Murmansk region, Russia) with and without thermal activation were used in a field experiment on the remediation of industrially polluted peat soil. According to the geochemical mobility of the components, one of four fractions was allocated depending on the acidic (HCl) concentration of the solution used for the material treatment: readily mobile (0.001 mol/L), mobile (0.01 mol/L), potentially mobile (0.1 mol/L), and acid-soluble (1.0 mol/L). This study showed that the addition of serpentinites to peat soil changed the fraction composition. The most significant changes were noted for serpentinite components such as Ca and Mg: their concentrations increased 2-3 times even in the smallest portion of serpentine material. On the contrary, the contents of metals in the readily mobile fraction decreased 3-18, 3-23, 5-26, and 2-42 times for Cu, Ni, Fe, and Al, respectively. The main factor causing the decrease in metal mobility was the pH rise due to the release of Ca and Mg compounds into the soil solution. This study showed that the addition of serpentine-containing material at 25 vol.% to peat soil was sufficient to create a geochemical barrier with a stable-functioning vegetation cover. All serpentine-containing materials are recommended for the remediation of large industrially polluted areas.

6.
Plant J ; 116(5): 1462-1476, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37646760

RESUMO

Plant growth and morphogenesis are determined by the mechanical properties of its cell walls. Using atomic force microscopy, we have characterized the dynamics of cell wall elasticity in different tissues in developing roots of several plant species. The elongation growth zone of roots of all species studied was distinguished by a reduced modulus of elasticity of most cell walls compared to the meristem or late elongation zone. Within the individual developmental zones of roots, there were also significant differences in the elasticity of the cell walls of the different tissues, thus identifying the tissues that limit root growth in the different species. In cereals, this is mainly the inner cortex, whereas in dicotyledons this function is performed by the outer tissues-rhizodermis and cortex. These differences result in a different behaviour of the roots of these species during longitudinal dissection. Modelling of longitudinal root dissection using measured properties confirmed the difference shown. Thus, the morphogenesis of monocotyledonous and dicotyledonous roots relies on different tissues as growth limiting, which should be taken into account when analyzing the localization of associated molecular events. At the same time, no matrix polysaccharide was found whose immunolabelling in type I or type II cell walls would predict their mechanical properties. However, assessment of the degree of anisotropy of cortical microtubules showed a striking correlation with the elasticity of the corresponding cell walls in all species studied.


Assuntos
Magnoliopsida , Raízes de Plantas , Raízes de Plantas/metabolismo , Meristema , Zea mays/metabolismo , Elasticidade , Parede Celular/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-37462588

RESUMO

BACKGROUND: The risk for invasive bacterial infection (IBI) in young infants with fever increases the use of invasive and therapeutic interventions, such as lumbar puncture (LP) and antimicrobials which may be unnecessary. In the present study, we analyzed whether viral pathogen(s) detection using a respiratory pathogen panel (RPP) alters the use of LP and antibiotics in 29-90-day-old infants presenting with fever to a regional pediatric hospital. METHODS: We collected medical history, clinical presentation, diagnostic tests and results, treatment, disposition, and length of stay (LOS) for selected patients. Data were compared between RPP positive (+) and RPP negative (-) infants. Use of LP and antibiotics were controlled for using regression analysis. P values <0.05 were considered significant. RESULTS: Among 172 RPP-tested infants, 45.4% had a virus(es). LP and antibiotics were used in 14.2% and 19.5% of infants in RPP(+) and in 17.0% and 28.7% in RPP(-) groups (P=0.60, 0.16), respectively. Nearly half of the infants in both groups were admitted and had comparable LOS. Hospitalization and at least one abnormal laboratory result were associated with a 2-3 times higher chance of LP and antibiotic utilization, irrespective to age and temperature level. No studied infant had been diagnosed with IBI, and 14.5% of infants in the RPP(-) group had bacteriuria. CONCLUSIONS: Detection of viral pathogen(s) did not significantly reduce the use of LP or antimicrobials in young infants with unexplained fever.

8.
Children (Basel) ; 10(7)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37508771

RESUMO

This study demonstrates the trend of computed tomography (CT) usage for children with mild traumatic brain injury (mTBI) in the context of the initiation of the Safe CT Imaging Collaborative Initiative to promote the Pediatric Emergency Care Applied Research Network (PECARN) rules at the acute care hospitals in New Jersey. We used administrative databases of 10 children's and 59 general hospitals to compare CT rates before 2014-2015, during 2016, and after the initiation of the program (2017-2019). The CT usage rates at baseline and the end of surveillance in children's hospitals (19.2% and 14.2%) were lower than in general hospitals (36.7% and 21.0%), p < 0.0001. The absolute mean difference from baseline to the end of surveillance in children's hospitals was 5.1% compared to a high of 9.7% in general hospitals, medium-high with 13.2%, and 14.0% in a medium volume of pediatric patients (p < 0.001-0.0001). The time-series model demonstrates a positive trend of CT reduction in pediatric patients with mTBI within four years of the program's implementation (p < 0.03-0.001). The primary CT reduction was recorded during the year of program implementation. Regression analysis revealed the significant role of a baseline CT usage rate in predicting the level of CT reduction independent of the volume of pediatric patients and type of hospital.

9.
Molecules ; 28(5)2023 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-36903620

RESUMO

Luminescent, heterometallic terbium(III)-lutetium(III) terephthalate metal-organic frameworks (MOFs) were synthesized via direct reaction between aqueous solutions of disodium terephthalate and nitrates of corresponding lanthanides by using two methods: synthesis from diluted and concentrated solutions. For (TbxLu1-x)2bdc3·nH2O MOFs (bdc = 1,4-benzenedicarboxylate) containing more than 30 at. % of Tb3+, only one crystalline phase was formed: Ln2bdc3·4H2O. At lower Tb3+ concentrations, MOFs crystallized as the mixture of Ln2bdc3·4H2O and Ln2bdc3·10H2O (diluted solutions) or Ln2bdc3 (concentrated solutions). All synthesized samples that contained Tb3+ ions demonstrated bright green luminescence upon excitation into the 1ππ* excited state of terephthalate ions. The photoluminescence quantum yields (PLQY) of the compounds corresponding to the Ln2bdc3 crystalline phase were significantly larger than for Ln2bdc3·4H2O and Ln2bdc3·10H2O phases due to absence of quenching from water molecules possessing high-energy O-H vibrational modes. One of the synthesized materials, namely, (Tb0.1Lu0.9)2bdc3·1.4H2O, had one of the highest PLQY among Tb-based MOFs, 95%.

10.
Pediatr Neonatol ; 64(2): 160-167, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36224067

RESUMO

BACKGROUND: The role of prematurity and pulmonary inflammation in the pathogenesis of bronchopulmonary dysplasia (BPD) is very well-defined. However, there is limited knowledge about whether the level of prematurity and surfactant therapy alter the pulmonary cytokines and endothelial growth factor (VEGF). METHODS: This study analyzed the VEGF and cytokines, including interleukin (IL)-1ß, IL-6, IL-8, and IL-10, and tumor necrosis factor α (TNF-α) in the tracheal aspirate (TA) of preterm infants obtained before (within 2 h after birth) and 10-12 h after the administration of the first dose of surfactant. TA was collected from 40 infants of 35 or fewer weeks of gestation, including extremely (Group 1, n = 19), very (Group 2, n = 13), and moderate/late (Group 2, n = 8) preterm neonates. In addition to univariate analysis, controlled regression models estimated the association of perinatal factors with the tested parameters and their role in the development of BPD. RESULT: We recorded significantly lower post-partum levels of VEGF and higher IL-8, IL-1ß, and TNF-α in the TA of Group 1 infants than in Group 2 and 3. Compared to the infants in Group 2 and 3, the post-surfactant increases of pulmonary VEGF, IL-8, IL-10, and TNF-α were more significant in Group 1. All tested parameters in Group 1 and 2 infants, before and after surfactant administration, were comparable. BPD was recorded in nearly 60% of the extremely preterm survivors and was significantly predicted by increased IL-8 before, and elevated TNF-α level after surfactant administration. CONCLUSION: This study indicates the association of birth at extremely preterm gestation with reduction in pulmonary VEGF and exacerbation of pro-inflammatory cytokines followed by greater elevation post-surfactant administration levels of VEGF, IL-8, TNF-α, and IL-10 than in neonates born with gestational age of 28-35 weeks.


Assuntos
Displasia Broncopulmonar , Pneumonia , Surfactantes Pulmonares , Lactente , Gravidez , Feminino , Recém-Nascido , Humanos , Recém-Nascido Prematuro/metabolismo , Interleucina-10 , Mediadores da Inflamação/metabolismo , Fator de Necrose Tumoral alfa , Tensoativos , Interleucina-8 , Fator A de Crescimento do Endotélio Vascular , Citocinas , Surfactantes Pulmonares/uso terapêutico , Displasia Broncopulmonar/etiologia
11.
Diagnostics (Basel) ; 12(11)2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36428849

RESUMO

The levels of angiogenic factors were analyzed in eight patients who underwent the embolization of chronic subdural hematoma (CSDH) with non-adhesive liquid embolic agents. Four of these patients had previously undergone surgical treatment for hematoma removal and had recurrences of a similar volume, and four had an increase in hematoma volume due to rebleeding. The levels of vascular endothelial growth factor (VEGF), matrix metallopeptidase 9 (MMP 9), angiopoietin-2 (Ang2), transforming growth factor beta 1 (TGF-ß1) and platelet-derived growth factor BB (PDGF-BB) in the arterial and venous blood were analyzed. The most significant results were obtained from the peripheral venous blood samples. The levels of VEGF in the samples of all the patients were close to normal or slightly decreased. There was an increase in the MMP9 levels (the factor that contributes to the disintegration of the vessel wall components) in all the patients. The Ang2 and especially the PDGF TGF-ß1 (the factor that plays an important role in the growth of the vessel wall from the already existing blood vessel tissue) levels were distinctly low in most of the cases and slightly elevated only in a number of patients who had previously been operated on. The results obtained show that there is an imbalance in the angiogenesis factors in patients with rebleeding CSDH. At the same time, the factors determining the formation of the vessel wall were reduced, and the levels of factors contributing to the degradation of extracellular matrix components were significantly increased. Such factors could help us to anticipate the increased risk of hemorrhages. Highlights: The levels of VEGF, MMP 9, Ang2, TGF-ß1 and PDGF-BB in the arterial and venous blood were analyzed. The most significant results were obtained from the peripheral venous blood samples. The results obtained show that there is an imbalance in the angiogenesis factors in patients with rebleeding CSDH. Such a profile of factors could help us to anticipate the increased risk of hemorrhages.

12.
Plant Sci ; 323: 111399, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35905894

RESUMO

Intrusive growth is a type of growth in which a cell exceeds the growth rate of its neighbours and intrudes between them, reaching a much greater length. This process provides plant fibres with their exceptional length. Fibres are the most abundant cell type in the mechanical tissues of plants. At the same time, the plant fibres are of fundamental importance for the production of textiles, paper, biocomposites, etc. Here we describe a mutant of flax (reduced fibre 1, rdf) in which intrusive growth of fibres is impaired in both phloem and xylem. In addition to the intrinsic differences in fibre length, the mutant is characterized by a constitutive gravitropic response, mechanical aberrations at the macro- and nanolevels, disruption of the cambium and uneven transition of xylem cells to secondary cell wall formation. Gelatinous cell walls in both phloem and xylem of mutant plants have disturbed structure and reduced elasticity. The existence of this mutant-control pair offers both prospects for finding the molecular players involved in triggering intrusive growth, cell wall thickening and for understanding the principles of plant mechanical tissue functioning.


Assuntos
Linho , Floema , Parede Celular/metabolismo , Linho/genética , Linho/metabolismo , Floema/metabolismo , Têxteis , Xilema/genética
13.
J Vis Exp ; (183)2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35662236

RESUMO

The mechanical properties of the primary cell walls determine the direction and rate of plant cell growth and, therefore, the future size and shape of the plant. Many sophisticated techniques have been developed to measure these properties; however, atomic force microscopy (AFM) remains the most convenient for studying cell wall elasticity at the cellular level. One of the most important limitations of this technique has been that only superficial or isolated living cells can be studied. Here, the use of atomic force microscopy to investigate the mechanical properties of primary cell walls belonging to the internal tissues of a plant body is presented. This protocol describes measurements of the apparent Young's modulus of cell walls in roots, but the method can also be applied to other plant organs. The measurements are performed on vibratome-derived sections of plant material in a liquid cell, which allows (i) avoiding the use of plasmolyzing solutions or sample impregnation with wax or resin, (ii) making the experiments fast, and (iii) preventing dehydration of the sample. Both anticlinal and periclinal cell walls can be studied, depending on how the specimen was sectioned. Differences in the mechanical properties of different tissues can be investigated in a single section. The protocol describes the principles of study planning, issues with specimen preparation and measurements, as well as the method of selecting force-deformation curves to avoid the influence of topography on the obtained values of elastic modulus. The method is not limited by sample size but is sensitive to cell size (i.e., cells with a large lumen are difficult to examine).


Assuntos
Parede Celular , Células Vegetais , Módulo de Elasticidade , Elasticidade , Microscopia de Força Atômica/métodos
15.
J Pediatr Pharmacol Ther ; 27(4): 366-372, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35558351

RESUMO

OBJECTIVE: Despite lack of benefit, antibiotics are overused in management of asthma exacerbation in children. In this study, data from a single children's hospital were analyzed to identify factors and outcomes associated with antibiotic use in children hospitalized with asthma. METHODS: The study population was identified by using administrative data from 2012 to 2015, with subsequent verification of asthma. We analyzed factors associated with antibiotic use (demographic, seasonal, clinical) and outcome (length of stay [LOS]) with respect to: 1) disposition to pediatric floor (PF) or pediatric intensive care unit (PICU); and 2) evidence of coexisting bacterial infection and/or fever. Statistical analysis included univariate and controlled regression models. Data are presented as median and IQR for continuous variables and OR and regression coefficient (ß) with 95% CIs for regression analyses. RESULTS: Of 600 patients, 28.8% were admitted to PICU, 14.8% had verified bacterial infection, and 53.8% received antibiotic, mainly azithromycin. Nearly all PICU patients were treated with antibiotic, irrespective of coexisting bacterial infection or fever. Among PF patients, nearly 30% without bacterial infection or fever and 40% with fever alone received antimicrobials. Overall risk for antibiotic treatment was associated with older age, female sex, desaturation events, oxygen supplementation, and PICU admission. Additionally, antibiotic treatment was associated with 13- to 19-hour increased LOS for PF patients without bacterial infection and/or fever. CONCLUSIONS: Almost half of pediatric patients admitted with asthma exacerbation received antibiotic therapy with no clear indication, which was associated with prolonged LOS.

16.
Planta ; 255(5): 108, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35449484

RESUMO

MAIN CONCLUSION: In cells of growing rye roots, xyloglucans and homogalacturonans demonstrate developmental stage specificity, while different xylans have tissue specificity. Mannans, arabinans and galactans are also detected within the protoplast. Mannans form films on sections of fresh material. The primary cell walls of plants represent supramolecular exocellular structures that are mainly composed of polysaccharides. Cell wall properties and architecture differ between species and across tissues within a species. We revised the distribution of cell wall polysaccharides and their dynamics during elongation growth and histogenesis in rye roots using nonfixed material and the spectrum of antibodies. Rye is a member of the Poaceae family and thus has so-called type II primary cell walls, which are supposed to be low in pectins and xyloglucans and instead have arabinoxylans and mixed-linkage glucans. However, rye cell walls at the earliest stages of cell development were enriched with the epitopes of xyloglucans and homogalacturonans. Mixed-linkage glucan, which is often considered an elongation growth-specific polysaccharide in plants with type II cell walls, did not display such dynamics in rye roots. The cessation of elongation growth and even the emergence of root hairs were not accompanied by the disappearance of mixed-linkage glucans from cell walls. The diversity of xylan motifs recognized by different antibodies was minimal in the meristem zone of rye roots, but this diversity increased and showed tissue specificity during root growth. Antibodies specific for xyloglucans, galactans, arabinans and mannans bound the cell content. When rye root cells were cut, the epitopes of xyloglucans, galactans and arabinans remained within the cell content, while mannans developed net-like or film-like structures on the surface of sections.


Assuntos
Mananas , Secale , Parede Celular/metabolismo , Epitopos/metabolismo , Galactanos/análise , Glucanos/metabolismo , Mananas/metabolismo , Pectinas/metabolismo , Polissacarídeos/metabolismo , Secale/metabolismo , Xilanos/metabolismo
17.
Artigo em Inglês | MEDLINE | ID: mdl-35373938

RESUMO

BACKGROUND: Utilization of procalcitonin (PCT) is challenging for hospital pediatricians because of uncertainty in clinical interpretation. We used a PCT decision cut-off value (<0.15 ng/mL) to identify if PCT can differentiate bacterial infections from viral and other conditions in pediatric patients who presented for hospital-based care. METHODS: This retrospective study included PCT tested patients who presented to our children's hospital from 2017 to 2020. We analyzed relevant demographic, laboratory, treatment, and clinical data, including discharge diagnoses consolidated into bacterial infections, viral syndromes, and other conditions by the highest PCT defined as ≤0.15 ng/mL (Group A) or >0.15 ng/mL (Group B). We used regression models to identify factors associated with PCT above decision limits and the role of PCT levels in the duration of antibiotic therapy. RESULTS: Of 238 patients, 32.8% constituted Group A. Bacterial infections represent 25.6% of diagnoses for patients in Group A and 55% for Group B (P<0.001), however, the distribution of bacterial infection types, including bacteremia, was comparable. Number of PCT tests performed and C-reactive protein (CRP) ≥5 mg/L, but no other factors were significantly associated with PCT >0.15 ng/mL. PCT levels did not predict the length of antibiotic therapy, which depended on duration of hospitalization and increased CRP. CONCLUSIONS: PCT as a single measurement above or below a decision cut-off value of 0.15 ng/mL does not specify bacterial infections or predict the duration of antibiotic therapy in hospitalized pediatric patients.

18.
J Clin Med ; 10(19)2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34640453

RESUMO

OBJECTIVE: Endovascular embolization using non-adhesive agents (e.g., ethylene vinyl alcohol copolymer with suspended micronized tantalum dissolved in dimethyl sulfoxide; Squid, Balt Extrusion) is an established treatment of brain arteriovenous malformations, dural arteriovenous fistulas, and hypervascular neoplasms. Middle meningeal artery (MMA) embolization is a relatively new concept for treating chronic subdural hematomas (CSDH). This study aimed to evaluate the safety and effectiveness of the use of Squid in the endovascular treatment of CSDH. METHODS: Embolization was offered to patients with CSDH with minimal or moderate neurological deficits and patients who had previously undergone open surgery to evacuate their CSDH without a significant effect. Distal catheterization of the MMA was followed by embolization of the hematoma capsule with Squid 12 or Squid 18. Safety endpoints were ischemic or hemorrhagic stroke and any other adverse event of the endovascular procedure. Efficacy endpoints were the feasibility of the intended procedure and a ≥ 50% reduction of the maximum depth of the CSDH confirmed by follow-up computed tomography (CT) after >3 months. RESULTS: Between November 2019 and July 2021, 10 patients (3 female and 7 male, age range 42-89 years) were enrolled. Five patients had bilateral hematomas, and five patients had previously been operated on with no significant effect and recurrent hematoma formation. The attempted embolization was technically possible in all patients. No technical or clinical complication was encountered. During a post-procedural follow-up (median 90 days), 10 patients improved clinically. A complete resolution of the CSDH was observed in 10 patients. The clinical condition of all enrolled patients during the so-far last contact was rated mRS 0 or 1. CONCLUSION: A distal catheterization of the MMA for the endovascular embolization of CSDH with Squid allowed for the devascularization of the MMA and the dependent vessels of the hematoma capsule. This procedure resulted in a partial or complete resolution of the CSDH. Procedural complications were not encountered.

19.
Front Hum Neurosci ; 15: 686388, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34557079

RESUMO

This review aims at clarifying the concept of first language attrition by tracing its limits, identifying its phenomenological and contextual constraints, discussing controversies associated with its definition, and suggesting potential directions for future research. We start by reviewing different definitions of attrition as well as associated inconsistencies. We then discuss the underlying mechanisms of first language attrition and review available evidence supporting different background hypotheses. Finally, we attempt to provide the groundwork to build a unified theoretical framework allowing for generalizable results. To this end, we suggest the deployment of a rigorous neuroscientific approach, in search of neural markers of first language attrition in different linguistic domains, putting forward hypothetical experimental ways to identify attrition's neural traces and formulating predictions for each of the proposed experimental paradigms.

20.
Front Plant Sci ; 12: 660375, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33936149

RESUMO

In the fibers of many plant species after the formation of secondary cell walls, cellulose-enriched cell wall layers (often named G-layers or tertiary cell walls) are deposited which are important in many physiological situations. Flax (Linum usitatissimum L.) phloem fibers constitutively develop tertiary cell walls during normal plant growth. During the gravitropic response after plant inclination, the deposition of a cellulose-enriched cell wall layer is induced in xylem fibers on one side of the stem, providing a system similar to that of tension wood in angiosperm trees. Atomic force microscopy (AFM), immunochemistry, and transcriptomic analyses demonstrated that the G-layer induced in flax xylem fibers was similar to the constitutively formed tertiary cell wall of bast (phloem) fibers but different from the secondary cell wall. The tertiary cell walls, independent of tissue of origin and inducibility, were twice as stiff as the secondary cell walls. In the gravitropic response, the tertiary cell wall deposition rate in xylem was higher than that of the secondary cell wall. Rhamnogalacturonan I (RG-I) with galactan side chains was a prominent component in cellulose-rich layers of both phloem and xylem flax fibers. Transcriptomic events underlying G-layer deposition in phloem and xylem fibers had much in common. At the induction of tertiary cell wall deposition, several genes for rhamnosyltransferases of the GT106 family were activated in xylem samples. The same genes were expressed in the isolated phloem fibers depositing the tertiary cell wall. The comparison of transcriptomes in fibers with both inducible and constitutive tertiary cell wall deposition and xylem tissues that formed the secondary cell walls is an effective system that revealed important molecular players involved in the formation of cellulose-enriched cell walls.

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