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1.
Front Plant Sci ; 15: 1444693, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39290731

RESUMEN

Hevea brasiliensis is an important cash crop with the product named natural rubber (NR) for markets. Ethylene (ET) is the most effective yield stimulant in NR production but the molecular mechanism remains incomplete. Here, latex properties analysis, transcriptome analysis, and metabolic profiling were performed to investigate the mechanism of NR yield increase in four consecutive tappings after ET stimulation. The results revealed that sucrose and inorganic phosphate content correlated positively with dry-rubber yield and were induced upon ET stimulation. Stimulation with ET also led to significant changes in gene expression and metabolite content. Genes involved in phytohormone biosynthesis and general signal transduction as well as 51 transcription factors potentially involved in the ET response were also identified. Additionally, KEGG annotation of differentially accumulated metabolites suggested that metabolites involved in secondary metabolites, amino-acid biosynthesis, ABC transporters, and galactose metabolism were accumulated in response to ET. Integrative analysis of the data collected by transcriptomics and metabolomics identified those differentially expressed genes and differentially accumulated metabolites are mainly involved in amino-acid biosynthesis and carbohydrate metabolism. Correlation analysis of genes and metabolites showed a strong correlation between amino-acid biosynthesis during ET stimulation. These findings provide new insights into the molecular mechanism underlying the ET-induced increase in rubber yield and further our understanding of the regulatory mechanism of ethylene signaling in rubber biosynthesis.

2.
Polymers (Basel) ; 16(17)2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39274038

RESUMEN

For polyacrylate latex pressure-sensitive adhesives (PSAs), high peel strength is of crucial significance. It is not only a key factor for ensuring the long-lasting and effective adhesive force of polyacrylate latex PSAs but also can significantly expand their application scope in many vital fields, such as packaging, electronics, and medical high-performance composite materials. High peel strength can guarantee that the products maintain stable and reliable adhesive performance under complex and variable environmental conditions. However, at present, the peel strength capacity of polyacrylate latex PSAs is conspicuously insufficient, making it difficult to fully meet the urgent market demand for high peel strength, and severely restricting their application in many cutting-edge fields. Therefore, based on previous experimental studies, and deeply inspired by the adhesion mechanism of natural marine mussels, in this study, a traditional polyacrylate latex PSA was ingeniously graft-modified with 3,4-dihydroxybenzaldehyde (DHBA) through the method of monomer-starved seeded semi-continuous emulsion polymerization, successfully synthesizing novel high-peel-strength polyacrylate latex pressure-sensitive adhesives (HPSAs) with outstanding strong adhesion properties, and the influence of DHBA content on the properties of the HPSAs was comprehensively studied. The research results indicated that the properties of the modified HPSAs were comprehensively enhanced. Regarding the water resistance of the adhesive film, the minimum water absorption rate was 4.33%. In terms of the heat resistance of the adhesive tape, it could withstand heat at 90 °C for 1 h without leaving residue upon tape peeling. Notably, the adhesive properties were significantly improved, and when the DHBA content reached 4.0%, the loop tack and 180° peel strength of HPSA4 significantly increased to 5.75 N and 825.4 gf/25 mm, respectively, which were 2.5 times and 2 times those of the unmodified PSA, respectively. Such superior adhesive performance of HPSAs, on the one hand, should be attributed to the introduction of the bonding functional monomer DHBA with a rich polyphenol structure; on the other hand, the acetal structure formed by the grafting reaction of DHBA with the PSA effectively enhanced the spatial network and crosslink density of the HPSAs. In summary, in this study, the natural biological adhesion phenomenon was ingeniously utilized to increase the peel strength of pressure-sensitive adhesives, providing a highly forward-looking and feasible direct strategy for the development of environmentally friendly polyacrylate latex pressure-sensitive adhesives.

3.
J Infect Chemother ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39270847

RESUMEN

This case report explores the utility of monitoring automated rapid plasma reagin (RPR) test results in both serum and cerebrospinal fluid (CSF) samples from a patient undergoing treatment for neurosyphilis. Syphilis treatment is based on the rapid plasma reagin (RPR) and syphilis treponema antibody levels, and in the case of RPR-positive syphilis, a 1/4 reduction in the RPR value by the manual card test is considered curative. However, it should be noted that when RPR is followed by the manual card test, there may seem to be no reduction when the automated method shows a steady reduction. In the present case, initially under surveillance for an unrelated condition, was found to have symptoms; imaging and serological findings suggestive of syphilis infection including syphilitic aortitis and neurosyphilis. After two weeks of high-dose intravenous Penicillin G, the patient was treated with oral amoxicillin as an indicator of RPR titers in both the serum and cerebrospinal fluid (CSF) by automated latex agglutination. RPR in serum automated latex agglutination decreased to 1/4 at 14 weeks and treatment was terminated, with a subsequent downward trend. The RPR using the manual card test was 1/2 at 14 weeks. If only the manual card method was used, the patient might require a longer treatment. In conclusion, the automated latex agglutination method for monitoring the treatment response may be useful, especially in patients with high RPR titers.

4.
Food Chem ; 463(Pt 1): 140960, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39236383

RESUMEN

Highly selective herbicide quinclorac (Qui) is a type of quinoline carboxylic acid hormone herbicide, which has the characteristics of long half-life and difficulty for degradation, causing high risk to the environmental safety. In this study, anti-Qui 8A3 monoclonal antibody (mAb) with good specificity and high affinity (3.89 × 109 L/mol) was prepared, and two kinds of lateral flow immunochromatographic strips (LFICS) including nano-flower nanoparticles (AuNF) - and latex microsphere (LM)- based LFICS were established based on the antibody and signal amplification. The linear range of the AuNF- and LM- based LFICS were 5.31-345.48 ng/mL and 2.52-257.92 ng/mL, respectively. The limit of detection (LOD) of the AuNF- and LM- based LFICS were determined to be 5.31 ng/mL and 2.52 ng/mL, respectively. In summary, the developed LFICS using AuNF and LM as signal amplification reporters exhibited excellent sensitivity and provided the rapid on-site screening of Qui and other analytes in food safety field.

5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(4): 958-963, 2024 Jul 20.
Artículo en Chino | MEDLINE | ID: mdl-39170021

RESUMEN

Objective: To investigate the biological safety of commercially available natural rubber latex and synthetic polyurethane condoms. Methods: Natural rubber latex condom brands of A1 and A2 and polyurethane condom brands of B1 and B2 were purchased from large chain pharmacies in Chengdu, with three packages randomly selected for each brand. The study assessed the toxic effects of condom extracts on L-929 mouse fibroblasts according to GB/T standards. Gross observation and histopathological evaluation were conducted to assess the irritation reactions of condoms on the vagina and penis of rabbits (3 rabbits were used for each brand), as well as their sensitization effects on guinea pig skin. Additionally, the impact of continuous perfusion of condom extracts of the vaginas of SD rats for 30 days on their reproductive systems was evaluated, following GB/T standards (5 rats were used for each brand). Results: Extracts from natural rubber latex condom brands A1 and A2, at concentrations of 100% and 50%, exhibited significant cytotoxicity, with optical density (OD) values being significantly lower than those of the blank control group and the polyurethane condom brands B1 and B2 (P<0.01). There was no significant difference in cell morphology and OD values between the extracts of B1 and B2 and the blank control group (P>0.05). Vaginal congestion was found in 3 rabbits from A1 group and 1 rabbit from the A2 group, while no obvious congestion was noted in rabbits from the B1 and the B2 groups. Histopathological examination showed scattered inflammatory cell infiltration in the vaginal tissue of 3 rabbits from the A1 group and 2 rabbits from the A2 group, and slight congestion in the blood vessels of the lamina propria. No obvious pathological changes were observed in the vaginal tissue of polyurethane brand rabbits. Two rabbits from the A1 group and 1 rabbit from the A2 group showed transient and mild erythema on the penis during the experiment. Histopathological examination showed that 1 rabbit from A1 group had small foci of pericapillary lymphocytes in the dermis of the penis, while no significant pathological changes were observed in the penile tissue of A2, B1, and B2 groups. After 30 days of continuous vaginal perfusion with condom extract, 3 rats in A1 group and 2 rats in the A2 group had uterine congestion, with the degree of congestion being lower in the A2 group. No significant congestion or pathological changes were observed in the vaginal and penile tissues of rabbits, or in the uterine tissues of rats from the polyurethane groups. None of the 4 groups of guinea pigs showed significant skin allergic reactions to the condom extracts. Conclusion: Significant differences in biosafety exist among condoms of various materials and brands. To ensure product safety, it is crucial to strengthen quality control and regulatory oversight after condoms become commercially available.


Asunto(s)
Condones , Látex , Poliuretanos , Ratas Sprague-Dawley , Animales , Conejos , Femenino , Cobayas , Ratas , Masculino , Látex/química , Ratones , Vagina/patología , Fibroblastos/efectos de los fármacos , Ensayo de Materiales , Goma/efectos adversos
6.
Cureus ; 16(7): e65002, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39161495

RESUMEN

Latex-fruit syndrome is characterized by hypersensitivity reactions to certain plant-derived foods in individuals allergic to natural rubber latex (NRL), affecting approximately 30-50% of NRL-allergic patients. This condition arises due to the cross-reactivity of IgE antibodies. Over time, this syndrome has been associated with an increased number of plant sources, including avocado, banana, chestnut, kiwi, peach, tomato, potato, and bell pepper. We present a case of an art student who developed latex-fruit syndrome following prolonged exposure to NRL art supplies.

7.
Surg Open Sci ; 20: 194-202, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39140104

RESUMEN

Objectives: We developed a new simulator for hands-on teaching of vascular surgical skills, the Leipzig Latex Patch Model (LPM). This study aimed to quantify the effectiveness and acceptance of the LPM evaluated by students, as well as evaluation of the results by experienced vascular surgeons. Methods: A prospective, single-center, single-blinded, randomized study was conducted. Fifty 5th-year medical students were randomized into two groups, first performing a patch suture on the LPM (study group) or established synthetic tissue model (control), then on porcine aorta. The second suture was videotaped and scored by two surgeons using a modified Objective Structured Assessment of Technical Skill (OSATS) score. We measured the time required for suturing; the participants completed questionnaires. Results: Participants required significantly less time for the second suture than the first (median: LPM 30 min vs. control 28.5 min, p = 0.0026). There was no significant difference in suture time between the groups (median: 28 min vs. 30 min, p = 0.2958). There was an increase in confidence from 28 % of participants before to 58 % after the course (p < 0.0001). The cost of materials per participant was 1.05€ (LPM) vs. 8.68€ (control). The OSATS-scores of the LPM group did not differ significantly from those of the control (median: 20.5 points vs. 23.0 points, p = 0.2041). Conclusions: This pilot study demonstrated an increase in technical skills and confidence through simulator-based teaching. Our data suggests comparable results of the LPM compared to the conventional model, as assessed by the OSATS-score. This low-cost, low-threshold training model for vascular suturing skills should make hands-on training more accessible to students and surgical residents. Key message: We developed and validated a low-cost, low-threshold training model for vascular suturing skills. This should make hands-on training more accessible to medical students and surgical residents in the future.

8.
Polymers (Basel) ; 16(16)2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39204507

RESUMEN

Organic electrochemical transistors (OECTs) have attracted considerable interest in the context of wearable and implantable biosensors due to their remarkable signal amplification combined with seamless integration into biological systems. These properties underlie OECTs' potential utility across a range of bioelectronic applications. One of the main challenges to their practical applications is the mechanical limitation of PEDOT:PSS, the most typical conductive polymer used as a channel layer, when the OECTs are applied to implantable and stretchable bioelectronics. In this work, we address this critical issue by employing natural rubber latex (NRL) as an additive in PEDOT:PSS to improve flexibility and stretchability of the OECT channels. Although the inclusion of NRL leads to a decrease in transconductance, mainly due to a reduced carrier mobility from 0.3 to 0.1 cm2/V·s, the OECTs maintain satisfactory transconductance, exceeding 5 mS. Furthermore, it is demonstrated that the OECTs exhibit excellent mechanical stability while maintaining their performance even after 100 repetitive bending cycles. This work, therefore, suggests that the NRL/PEDOT:PSS composite film can be deployed for wearable/implantable applications, where high mechanical stability is needed. This finding opens up new avenues for practical use of OECTs in more robust and versatile wearable and implantable biosensors.

9.
Acta Crystallogr D Struct Biol ; 80(Pt 9): 675-685, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39207895

RESUMEN

Several proteins from plant pathogenesis-related family 10 (PR10) are highly abundant in the latex of opium poppy and have recently been shown to play diverse and important roles in the biosynthesis of benzylisoquinoline alkaloids (BIAs). The recent determination of the first crystal structures of PR10-10 showed how large conformational changes in a surface loop and adjacent ß-strand are coupled to the binding of BIA compounds to the central hydrophobic binding pocket. A more detailed analysis of these conformational changes is now reported to further clarify how ligand binding is coupled to the formation and cleavage of an intermolecular disulfide bond that is only sterically allowed when the BIA binding pocket is empty. To decouple ligand binding from disulfide-bond formation, each of the two highly conserved cysteine residues (Cys59 and Cys155) in PR10-10 was replaced with serine using site-directed mutagenesis. Crystal structures of the Cys59Ser mutant were determined in the presence of papaverine and in the absence of exogenous BIA compounds. A crystal structure of the Cys155Ser mutant was also determined in the absence of exogenous BIA compounds. All three of these crystal structures reveal conformations similar to that of wild-type PR10-10 with bound BIA compounds. In the absence of exogenous BIA compounds, the Cys59Ser and Cys155Ser mutants appear to bind an unidentified ligand or mixture of ligands that was presumably introduced during expression of the proteins in Escherichia coli. The analysis of conformational changes triggered by the binding of BIA compounds suggests a molecular mechanism coupling ligand binding to the disruption of an intermolecular disulfide bond. This mechanism may be involved in the regulation of biosynthetic reactions in plants and possibly other organisms.


Asunto(s)
Disulfuros , Látex , Papaver , Proteínas de Plantas , Papaver/metabolismo , Papaver/química , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Disulfuros/química , Disulfuros/metabolismo , Látex/química , Látex/metabolismo , Cristalografía por Rayos X , Ligandos , Conformación Proteica , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Sitios de Unión , Bencilisoquinolinas/metabolismo , Bencilisoquinolinas/química , Unión Proteica
10.
PeerJ ; 12: e17877, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39131614

RESUMEN

Background: Plants allocate resources to growth, defense, and stress resistance, and resource availability can affect the balance between these allocations. Allocation patterns are well-known to differ among species, but what controls possible intra-specific trade-offs and if variation in growth vs. defense potentially evolves in adaptation to resource availability. Methods: We measured growth and defense in a provenance trial of rubber trees (Hevea brasiliensis) with clones originating from the Amazon basin. To test hypotheses on the allocation to growth vs. defense, we relate biomass growth and latex production to wood and leaf traits, to climate and soil variables from the location of origin, and to the genetic relatedness of the Hevea clones. Results: Contrary to expectations, there was no trade-off between growth and defense, but latex yield and biomass growth were positively correlated, and both increased with tree size. The absence of a trade-off may be attributed to the high resource availability in a plantation, allowing trees to allocate resources to both growth and defense. Growth was weakly correlated with leaf traits, such as leaf mass per area, intrinsic water use efficiency, and leaf nitrogen content, but the relative investment in growth vs. defense was not associated with specific traits or environmental variables. Wood and leaf traits showed clinal correlations to the rainfall and soil variables of the places of origin. These traits exhibited strong phylogenetic signals, highlighting the role of genetic factors in trait variation and adaptation. The study provides insights into the interplay between resource allocation, environmental adaptations, and genetic factors in trees. However, the underlying drivers for the high variation of latex production in one of the commercially most important tree species remains unexplained.


Asunto(s)
Hevea , Látex , Hojas de la Planta , Hevea/genética , Hevea/crecimiento & desarrollo , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Látex/metabolismo , Biomasa , Madera/genética , Filogenia , Especificidad de la Especie
11.
Chem Biodivers ; : e202400993, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136195

RESUMEN

Six compounds were isolated from lettuce latex. They were identified as 2,5-dihydroxybenzaldehyde (1), 3ß-hydroxy-4,15-dehydrograndolide (2), annuolide D (3), lactucin (4), lactucopicrin (5), and hanphyllin (6). Bioassays showed that the inhibition rate of compound 1 (2,5-dihydroxybenzaldehyde) and 6 (hanphyllin, a sesquiterpene lactone) on the weight gain of S. litura were 52.4% and 10%, respectively, at the concentration of 100 µg/g. RNA-seq analyses showed that larval exposure to compound 1 down-regulated the genes associated with heterobiotic metabolism including drug metabolism-cytochrome P450, metabolism of xenobiotics by cytochrome P450, retinol metabolism, glutathione metabolism, and drug metabolism-other enzymes (mainly uridine diphosphate glucuronyltransferase, UGTs). RT-qPCR further confirmed that 33 genes in the family of carboxylesterase (CarE), P450s and UGTs were down-regulated by compound 1. The activities of CarE, P450s and UGTs in the larvae fed on diets containing compound 1 were significantly lower than those fed on control diets, with the inhibition for the three detoxification enzymes being 55.4%, 53.9%, and 52.9%. These findings suggest that secondary metabolites including 2,5-dihydroxybenzaldehyde in the latex play a key role in protecting lettuce from insect herbivory.

12.
Ann Anat ; 256: 152312, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39059507

RESUMEN

INTRODUCTION: Postmortem evaluation of the human vascular system has a long history, with advancements ranging from dissections to modern imaging techniques like computed tomography (CT scan). This study designs a novel combination of Angiofil, a liquid radiopaque polymer, and latex, a flexible cast material, for cadaveric vascular analysis. MATERIAL & METHODS: The aim was to synergize the advantages of both components, providing accurate radiological images and optimal dissection conditions. Three arterial territories (lateral circumflex femoral artery, profunda brachii artery, and radial artery) were injected and assessed through CT scans and dissections. RESULTS: The Angiofil-latex mixture allowed successful visualization of the vascular networks, offering a simple, reproducible, and non-toxic approach. Quantitative assessments of the three territories, including diameters and lengths, showed comparable results between CT scan and dissection. DISCUSSION: The technique precision and versatility make it an accessible and valuable tool for anatomical studies, potentially extending its application to MRI analyses. Overall, the Angiofil-latex combination presents a cost-effective solution for researchers, offering enhanced visibility and detailed anatomical insights for various applications, including anatomical variation studies.


Asunto(s)
Cadáver , Arteria Femoral , Látex , Tomografía Computarizada por Rayos X , Humanos , Tomografía Computarizada por Rayos X/métodos , Arteria Femoral/anatomía & histología , Arteria Femoral/diagnóstico por imagen , Disección/métodos , Extremidades/irrigación sanguínea , Extremidades/diagnóstico por imagen , Extremidades/anatomía & histología , Masculino , Arterias/anatomía & histología , Arterias/diagnóstico por imagen , Arteria Radial/anatomía & histología , Arteria Radial/diagnóstico por imagen , Femenino , Anciano , Medios de Contraste/administración & dosificación
13.
Braz J Microbiol ; 55(3): 2119-2130, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38954220

RESUMEN

Biosurfactants, sustainable alternatives to petrochemical surfactants, are gaining attention for their potential in medical applications. This study focuses on producing, purifying, and characterizing a glycolipid biosurfactant from Candida sp. UFSJ7A, particularly for its application in biofilm prevention on siliconized latex catheter surfaces. The glycolipid was extracted and characterized, revealing a critical micellar concentration (CMC) of 0.98 mg/mL, indicating its efficiency at low concentrations. Its composition, confirmed through Fourier transform infrared spectroscopy (FT-IR) and thin layer chromatography (TLC), identified it as an anionic biosurfactant with a significant ionic charge of -14.8 mV. This anionic nature contributes to its biofilm prevention capabilities. The glycolipid showed a high emulsification index (E24) for toluene, gasoline, and soy oil and maintained stability under various pH and temperature conditions. Notably, its anti-adhesion activity against biofilms formed by Escherichia coli, Enterococcus faecalis, and Candida albicans was substantial. When siliconized latex catheter surfaces were preconditioned with 2 mg/mL of the glycolipid, biofilm formation was reduced by up to 97% for E. coli and C. albicans and 57% for E. faecalis. These results are particularly significant when compared to the efficacy of conventional surfactants like SDS, especially for E. coli and C. albicans. This study highlights glycolipids' potential as a biotechnological tool in reducing biofilm-associated infections on medical devices, demonstrating their promising applicability in healthcare settings.


Asunto(s)
Biopelículas , Candida , Catéteres , Glucolípidos , Tensoactivos , Glucolípidos/farmacología , Glucolípidos/química , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Tensoactivos/farmacología , Tensoactivos/química , Candida/efectos de los fármacos , Candida/fisiología , Catéteres/microbiología , Látex/química , Látex/farmacología , Escherichia coli/efectos de los fármacos , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecalis/fisiología , Candida albicans/efectos de los fármacos , Candida albicans/fisiología
14.
Anal Biochem ; 694: 115601, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38971527

RESUMEN

The measurement of free hemoglobin (free Hb) in blood is crucial for assessing the risk of organ damage in patients with hemolytic diseases. However, the colorimetric method, commonly used in clinical practice, does not distinguish between free Hb and the hemoglobin-haptoglobin complex (Hb-Hp) in the blood, instead reflecting the total Hb level. Although size-exclusion high-performance liquid chromatography (SEC-HPLC) can specifically measure free Hb, its clinical use is limited by long assay times. Here, we developed a novel assay method for the rapid quantification of free Hb in serum, distinguishing it from Hb-Hp, using a latex agglutination immunoturbidimetric assay (LATIA). This method could be used to measure free Hb in sera in the range of 1-100 µg/mL in approximately 15 min using an automatic biochemistry analyzer. Using Hb-spiked serum samples from healthy adults, there was a high correlation with Hb levels determined using the newly developed method and SEC-HPLC, indicating a high specificity for free Hb. This novel assay can be used to monitor levels of free Hb in patients with various hemolytic diseases and to design therapeutic strategies based on measured values. However, further studies are required to assess its clinical performance.


Asunto(s)
Haptoglobinas , Hemoglobinas , Humanos , Haptoglobinas/análisis , Hemoglobinas/análisis , Cromatografía Líquida de Alta Presión/métodos , Inmunoturbidimetría/métodos , Adulto , Pruebas de Fijación de Látex/métodos , Cromatografía en Gel/métodos
15.
Methods Mol Biol ; 2814: 81-88, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38954198

RESUMEN

Uptaking particulate objects and bulk liquid by eucaryotic cells is critical for their growth, survival, and defense. Dictyostelium is a model organism spearheaded to uncover mechanisms behind various types of uptaking activities. Here, we describe assays measuring phagocytosis and macropinocytosis using Dictyostelium discoideum.


Asunto(s)
Dictyostelium , Fagocitosis , Pinocitosis , Dictyostelium/fisiología , Pinocitosis/fisiología
16.
Genes (Basel) ; 15(7)2024 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-39062736

RESUMEN

The spurge Euphorbia characias is known for its latex, which is rich in antioxidant enzymes and anti-phytopathogen molecules. In this study, we identified a novel polyubiquitin protein in the latex and leaves, leading to the first molecular characterization of its coding gene and expressed protein in E. characias. Using consensus-degenerate hybrid oligonucleotide primers (CODEHOP) and rapid amplification of cDNA ends (5'/3'-RACE), we reconstructed the entire open reading frame (ORF) and noncoding regions. Our analysis revealed that the polyubiquitin gene encodes five tandemly repeated sequences, each coding for a ubiquitin monomer with amino acid variations in four of the five repeats. In silico studies have suggested functional differences among monomers. Gene expression peaked during the summer, correlating with high temperatures and suggesting a role in heat stress response. Western blotting confirmed the presence of polyubiquitin in the latex and leaf tissues, indicating active ubiquitination processes. These findings enhance our understanding of polyubiquitin's regulatory mechanisms and functions in E. characias, highlighting its unique structural and functional features.


Asunto(s)
Euphorbia , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Poliubiquitina , Euphorbia/genética , Poliubiquitina/genética , Poliubiquitina/metabolismo , Proteínas de Plantas/genética , Estaciones del Año , Látex/metabolismo , Látex/química , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Filogenia
17.
Community Dent Health ; 41(3): 202-207, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39082846

RESUMEN

BACKGROUND: Despite concerns such as allergic dermatitis and bans recommended by health authorities, latex gloves are used by dental professionals in many countries. There are published reports of the prevalence of latex allergy in health professionals including dental professionals; however, no systematic review and meta-analysis is available. OBJECTIVES: To determine the prevalence of latex allergy in dental professionals. METHOD: Two researchers independently searched articles using appropriate keyword combinations in three search engines; PubMed, Cochrane Library, and Google Scholar for observational studies on latex allergy in dental professionals reported in English or where complete translations in English were included. Percentage prevalence of latex allergy was the variable of interest. The risk of bias was assessed using the Hoy et al. (2012) tool and publication bias using a funnel plot. RESULTS: From 435 possible sources, a total of 14 studies were included in the review and meta-analysis. The prevalence of latex allergy, based on 6302 participants was 10.37% (95% CI: 7.31 to 13.88). Heterogeneity (I2) was high (94.13%); hence, REM was used. There was moderate risk of bias across studies and minimal publication bias. GRADE analysis indicated that the evidence was uncertain. CONCLUSIONS: The prevalence of latex allergy in dental professionals is about 10.37%. Evidence is of low quality due to high heterogeneity.


Asunto(s)
Odontólogos , Hipersensibilidad al Látex , Hipersensibilidad al Látex/epidemiología , Humanos , Prevalencia , Odontólogos/estadística & datos numéricos
18.
Arch Argent Pediatr ; : e202410431, 2024 07 11.
Artículo en Español | MEDLINE | ID: mdl-38967622

RESUMEN

Latex allergy, or natural rubber latex allergy (NRLA), is a global health concern, even among the pediatric population, with symptoms varying in severity from mild to potentially life-threatening. Latex is derived from the Hevea Brasiliensis tree, producing twelve million tons annually for use in various everyday and medical products. Despite efforts to mitigate NRLA, its prevalence remains high, especially in at- risk groups such as children with spina bifida. Clinical manifestations include immediate and delayed symptoms, even anaphylactic reactions. Diagnosis involves a detailed medical history and specific tests. Prevention focuses on avoiding exposure, especially in medical and educational settings. Treatment, including immunotherapy, exhibits variable efficacy. NRLA has a strong negative impact on children's quality of life. The objective of this publication is to provide updated information and practical tools for the pediatrician's and allergist's practice.


La alergia al látex del caucho natural (ALCN) es un problema de salud global, incluso en población pediátrica, con síntomas de gravedad variable, desde leves hasta potencialmente mortales. El látex se obtiene del árbol Hevea brasiliensis; se producen doce millones de toneladas anuales que se utilizan en diversos productos cotidianos y médicos. A pesar de los esfuerzos para mitigar la ALCN, su prevalencia sigue siendo alta, especialmente en grupos de riesgo, como niños con espina bífida. Las manifestaciones clínicas incluyen síntomas inmediatos y retardados, hasta reacciones anafilácticas. El diagnóstico requiere una historia clínica detallada y pruebas específicas. La prevención se centra en evitar la exposición, especialmente en entornos médicos y escolares. El tratamiento, incluida la inmunoterapia, muestra eficacia variable. La ALCN tiene un fuerte impacto negativo en la calidad de vida. El objetivo de esta publicación es proveer información actualizada y herramientas prácticas para el consultorio del pediatra y el alergólogo.

19.
Heliyon ; 10(13): e33421, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39040337

RESUMEN

Hevea brasiliensis, a natural rubber producing species, is widely cultivated due to its high rubber yield potential. Natural rubber is synthesised in the rubber particles of laticifers. Latex diagnosis (LD) was established to characterise the physiological state of the laticiferous system by measuring its physiological parameters, i.e., sucrose, inorganic phosphorous (Pi), thiols and total solid content (TSC). Rubber clones are often classified in three groups i.e., quick starters, medium starters and slow starters. To better understand the genetic bases of latex yield, a biparental population was generated from a cross between the quick-starter clone PB 260 and the medium-starter clone SP 217. LD was performed during the peak latex production season and used to calculate sucrose loading. The agronomic and physiological parameters associated with latex yield led to the classification of genotypes according to the rubber clonal typology and to the identification of quantitative trait loci (QTL) using a high-density map. Inorganic phosphorous content was positively associated with yield during the first year of production thus enabling identification of quick-starter clones. In addition, the LD-based clonal typology led to determine the long-term yield potential and the use of appropriate ethephon stimulation. QTL analysis successfully identified several QTLs related to yield, sucrose, Pi and TSC. One QTL related to sucrose loading was identified in the same position as the QTL for sucrose on linkage group 1. To our knowledge, this is the first study to report QTL analysis for this trait. The use of a high-density map enables the identification of genes underlying QTLs. Several putative genes underlying QTLs related to yield, sucrose and TSC were identified.

20.
J Clin Med ; 13(14)2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39064262

RESUMEN

Thirty years have passed since the concept of latex-fruit syndrome (LFS) was first introduced. Since then, this phenomenon, characterized by cross-reactivity between natural latex rubber allergens and certain fruit allergens, has been extensively studied. This literature review sought to determine the prevalence of LFS in latex-allergic patients, identify the most common cross-reactions with fruit allergens in individuals with LFS, and understand the clinical manifestations of this syndrome. An extensive literature search was carried out using PubMed and Scopus databases, while applying the Preferred Reporting Items for Systematic Reviews and Meta-Analysis methodology. The analysis of original studies revealed a wide variation in LFS prevalence (4-88%) influenced by diverse diagnostic tools, different geographical regions, and the size of study populations. Our findings indicate that the most prevalent allergenic fruits in patients with LFS are banana, avocado, kiwifruit, and papaya. After evaluating the symptoms of the fruit hypersensitivity of patients with LFS, the clinical manifestation of hypersensitivity constituted 73% of systemic allergy symptoms and only 27% of reported symptoms described the localized allergy. Furthermore, the clinical picture of latex-fruit syndrome is illustrated through two cases, one typical and one with an unusual presentation. Their clinical features were assessed and contrasted utilizing different anaphylaxis severity grading criteria. To properly manage LFS, it is essential to establish standardized diagnostic criteria and severity grading systems, as these are crucial for accurate diagnosis and effective treatment.

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