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Little is known about nematode communities related to Costa Rican crops, which limits the efforts to offer adequate responses to producers interested in soil conservation. The objective of this work was to describe nematode fauna of pineapple plantations in the northern plains of Costa Rica as an example of how agronomical management practices can influence nematode diversity. The abundance of families (or genera) of the nematode communities in soil samples of 15 pineapple plantations and 11 patches of forests or tree plantations near them was calculated. Forty-three families were identified, 39 families in forest, 36 in tree plantations, and 35 in pineapple plantations. Helicotylenchus was the most abundant genus in pineapple, while Discocriconemella dominated in forests and tree plantations. Non-metric multidimensional scaling and redundancy analysis showed few differences but revealed that forests and tree plantations correlated with organic matter, Ca, Mg, and with Discocriconemella. Meanwhile, pineapple plantations correlated with exchangeable acidity, K, and with abundance of Mesocriconema. Basal index was significantly lower in forest and tree plantations while the Structure index was higher. Other calculated indexes (Plant-parasitic index, Maturity index, Channel index, Enrichment index, and Metabolic Footprints) did not show any statistical differences among land uses. Most statistical differences were found at the nematode genus level. [ABSTRACT FROM AUTHOR]

The new species Metaxonchium toroense n. sp. from natural habitats of Costa Rica is described, including light microscopy (LM), scanning electron microscopy (SEM) and molecular (D2–D3 28S rDNA) analyses. The new species is characterized by its general size, the dimensions and appearance of its lip region, the length of the odontostyle and its fusiform aspect, the length of the neck and its pharyngeal expansion, the reduction of the anterior genital branch to a very short uterine sac without any rudiment of ovary or oviduct, tripartite and non-echinophor posterior uterus, the somewhat posterior vulva position, the length and shape of the caudal region, and the absence of males. Molecular analyses, the first to be performed on a Metaxonchium species, show a close relationship of the new species with representatives of the genera Axonchoides and Syncheilaxonchium. [ABSTRACT FROM AUTHOR]

Introduction: Rotavirus-associated diarrheal diseases significantly burden healthcare systems, particularly affecting infants under five years. Both Rotarix™ (RV1) and RotaTeq™ (RV5) vaccines have been effective but have distinct application schedules and limited interchangeability data. This study aims to provide evidence on the immunogenicity, reactogenicity, and safety of mixed RV1-RV5 schedules compared to their standard counterparts., Methods: This randomized, double-blind study evaluated the non-inferiority in terms of immunogenicity of mixed rotavirus vaccine schedules compared to standard RV1 and RV5 schedules in a cohort of 1,498 healthy infants aged 6 to 10 weeks. Participants were randomly assigned to one of seven groups receiving various combinations of RV1, and RV5. Standard RV1 and RV5 schedules served as controls of immunogenicity, reactogenicity, and safety analysis. IgA antibody levels were measured from blood samples collected before the first dose and one month after the third dose. Non-inferiority was concluded if the reduction in seroresponse rate in the mixed schemes, compared to the standard highest responding scheme, did not exceed the non-inferiority margin of -0.10. Reactogenicity traits and adverse events were monitored for 30 days after each vaccination and analyzed on the entire cohort., Results: Out of the initial cohort, 1,365 infants completed the study. Immunogenicity analysis included 1,014 infants, considering IgA antibody titers ≥20 U/mL as seropositive. Mixed vaccine schedules demonstrated non-inferiority to standard schedules, with no significant differences in immunogenic response. Safety profiles were comparable across all groups, with no increased incidence of serious adverse events or intussusception., Conclusion: The study confirms that mixed rotavirus vaccine schedules are non-inferior to standard RV1 and RV5 regimens in terms of immunogenicity and safety. This finding supports the flexibility of rotavirus vaccination strategies, particularly in contexts of vaccine shortage or logistic constraints. These results contribute to the global effort to optimize rotavirus vaccination programs for broader and more effective pediatric coverage. Clinical trial registration : ClinicalTrials.gov, NCT02193061., Competing Interests: PV-V and MM-P have served as consultants to MSD México on unrelated topics. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Macías-Parra, Vidal-Vázquez, Reyna-Figueroa, Rodríguez-Weber, Moreno-Macías, Hernández-Benavides, Fortes-Gutiérrez, Richardson and Vázquez-Cárdenas.)

We report development and preparation of synthetic polypeptide based, coacervate core polyelectrolyte complex micelles, PCMs, in aqueous media, which were characterized and evaluated for the encapsulation and in vitro release of a model single-stranded RNA, polyadenylic acid, poly(A). Cationic, α-helical polypeptides pegylated at their N-termini, PEG 113 -b-5b n and PEG 113 -b-5c n, were designed to form coacervate core PCMs upon mixing with multivalent anions in aqueous media. Sodium tripolyphosphate (TPP) and poly(A) were used as model multivalent anions that allowed optimization of polypeptide composition and chain length for formation of stable, nanoscale PCMs. PEG 113 -b-5c 27 was selected for preparation of PCMs that were characterized under different environmental conditions using dynamic light scattering, atomic force microscopy and cryoelectron microscopy. The PCMs were found to efficiently encapsulate poly(A), were stable at physiologically relevant pH and solution ionic strength, and were able to release poly(A) in the presence of excess polyvalent anions. These PCMs were found to be a promising model system for further development of polypeptide based therapeutic delivery vehicles., (© 2023. The Author(s), under exclusive licence to EDP Sciences, SIF and Springer-Verlag GmbH Germany, part of Springer Nature.)

We report the preparation of a new water-soluble, nonionic homopolypeptide poly(l-homoserine) as well as poly(l-homoserine) block copolymers with controllable segment lengths. The conformational preferences of poly(l-homoserine) were also determined in both the solid state and in solution. Poly(l-homoserine) is soluble in water and adopts a disordered conformation that makes it a promising addition to the small class of nonionic, water-soluble homopolypeptides with potential for development for applications in biology. Toward this goal, a poly(l-homoserine) containing a block copolypeptide was prepared and found to assemble into micro- and nanoscale vesicles in water.

Objectives: To present a case of uterine necrosis following hemostatic suturing to control postpartum bleeding, and to review the literature in order to identify the suture techniques employed, clinical findings, diagnostics and treatment in the clinical cases described., Material and Methods: A 34-year-old woman presenting with abdominal pain eight days after cesarean delivery due to placenta previa who required B-Lynch compression suture due to uterine atony, and who was diagnosed with uterine necrosis. The patient underwent total abdominal hysterectomy with a satisfactory recovery. A systematic literature search was conducted in the Medline vía Pubmed, Embase and Web of Science databases. The search included case series and reports, and cohorts of women with uterine necrosis following the use of uterine compression sutures for postpartum bleeding. The analysis included sociodemographic and clinical variables at the time of diagnosis, suturing technique, diagnostic tests and treatment., Results: Overall, 23 studies with 24 patients were included. Of all necrosis cases, 83% occurred following cesarean section. B-Lynch was the suturing technique most frequently used (66 %), followed by the Cho suture (25 %). The most frequent symptoms were fever and abdominal pain. The most commonly used diagnostic test was computed tomography (9/24 cases). Hysterectomy was performed in the majority of cases (75 %)., Conclusions: Although rare, uterine wall necrosis is a serious complication. It would be advisable to design follow-up cohort studies of women undergoing these procedures in order to determine the incidence of associated complications.

Via the design of a new, soluble poly( S -alkyl-l-cysteine) precursor, a route was developed for the successful preparation of long-chain poly(dehydroalanine), A DH , as well as the incorporation of dehydroalanine residues and A DH segments into copolypeptides. Based on experimental and computational data, A DH was found to adopt a previously unobserved "hybrid coil" structure, which combines the elements of 2 5 -helical and 3 10 -helical conformations. Analysis of the spectroscopic properties of A DH revealed that it possesses a strong inherent blue fluorescence, which may be amenable for use in imaging applications. A DH also contains reactive electrophilic groups that allowed its efficient modification to functionalized polypeptides after reactions under mild conditions with thiol and amine nucleophiles. The combined structural, spectroscopic, and reactivity properties of A DH make it a unique reactive and fluorescent polypeptide component for utilization in self-assembled biomaterials.

Background: Maternal obesity is a risk factor for multiple obstetrics complications and adverse outcomes. The objective of the study was to investigate the association between obesity (IMC >30) and fetal acidosis at birth., Methods and Findings: This hospital-based cohort study was based on 24,307 live-born infants in which maternal body mass index (BMI) information was available and delivered in the Granada north region during 2007-2018 from data of the Hospital Medical Birth Registry. Multivariate using logistic regression was performed to assess the association between fetal acidosis and BMI, crude, and adjusted odds ratio of fetal acidosis were calculated. p  < .05 was considered statistically significant. We adjusted by maternal age, parity, hypertension, diabetes, and smoking habits. In the study population of 17,167 term live births, 518 infants (3.02%) had an umbilical cord blood pH < 7.10. The obesity rate in mothers with acidosis at delivery was 12.7%, but morbid obesity rate was 2.51% (adjusted OR 1.82)., Conclusion: This study strengthens the evidence that demonstrates that morbid obesity is an independent risk factor for fetal acidosis at birth.

The lack of knowledge about biological communities residing in soils, especially those in tropical regions, represents a constraint to management practices to take advantage of the ecological services provided by soil microbiota to agroecosystems. One of the complexities derived from describing biological diversity in such tropical conditions comes from the methods used to isolate microorganisms without altering the composition of the sample. The goal of this study was to establish a protocol for adequate soil sampling and environmental DNA extraction from a tropical region in Costa Rica. We present an up-to-date protocol optimized for tropical soils which improves sevenfold the amount of DNA extracted without significantly affecting the 260/280 and 260/230 ratios compared with commercially available kits and standard protocols.

Ureaplasma parvum is the most prevalent genital mycoplasma in women of childbearing age. There is debate around the relevance of its presence in male or female genitals for disease development and as a cofactor. The objective of this study was to determine the prevalence of colonization/infection by U. parvum and its possible relationship with reproductive tract infections. We retrospectively analyzed the presence of U. parvum in patients referred by specialist clinicians for suspicion of genitourinary tract infection. U. parvum was detected in 23.8% of samples, significantly more frequently in females (39.9%) than in males (6%). Among the males, U. parvum was found alone in 68.4% of episodes, with Ct < 30. Among the females, U. parvum was detected in 88.6% of cases, with Ct < 30, including 22 cases with premature rupture of membranes and 6 cases with threat of preterm labor. Co-infection was significantly more frequent in females (62.6%) than in males (31.6%). Given the high prevalence of U. parvum as sole isolate in males and females with genitourinary symptoms, it should be considered in the diagnosis and treatment of genital infections, although its pathogenic role in some diseases has not been fully elucidated.

Flavobacterium psychrophilum is the causative agent of bacterial cold-water disease and rainbow trout syndrome in freshwater salmonid fish worldwide, generating injuries and high mortality rates. Despite several studies on this bacterium, the infection mechanism remains unknown due to limitations in the employed animal models. In this work, we propose using zebrafish (Danio rerio) as a model for studying bacterial pathogenicity. To substantiate this proposal, zebrafish infection by F. psychrophilum strain JIP 02/86 was characterized. Zebrafish larvae were infected using the bath method, and morphological changes and innate immune system activation were monitored using transgenic fish. Salmonid-like infection phenotypes were observed in 4.74% of treated larvae, as manifested by fin, muscle and caudal peduncle damage. Symptomatic and dead larvae accounted for 1.35% of all challenged larvae. Interestingly, infected larvae with no infection phenotypes showed stronger innate immune system activation than specimens with phenotypes. A failure of function assay for myeloid factor pu.1 resulted in more infected larvae (up to 43.5%), suggesting that low infection rates by F. psychrophilum would be due to the protective actions of the innate immune system against this bacterium in zebrafish larvae. Our results support the use of zebrafish as an infection model for studying F. psychrophilum. Furthermore, the percentage of infected fish can be modulated by disturbing, to varying extents, the differentiation of myeloid cells. Using this evidence as a starting point, different aspects of the infection mechanism of F. psychrophilum could be studied in vivo., (© 2020 John Wiley & Sons Ltd.)

Alloscardovia omnicolens is a recently-reported microorganism with unknown pathogenic implications. It has been isolated in various clinical localizations but not in the endocervix. We isolated A. omnicolens in an endocervical sample from a 31-yr-old patient with preterm premature rupture of membranes (PPROM) in week 33+3 of pregnancy. The main risk of PPROM is prematurity and the possibility of developing infectious chorioamnionitis, which can be lethal for the mother and newborn. This is the first report of an association between A. omnicolens and PPROM, although its pathogenic role has not yet been elucidated.

A new species of the genus Aporcelinus, A. elongicaudatus sp. n., collected from natural habitats of Costa Rica, is described and illustrated. The new species is characterized by its 0.92-1.05 mm long body, lip region offset by weak constriction and 15 µm broad, odontostyle 15-18 µm or 1.0-1.2 times the lip region diameter, neck 270-300 µm long, pharyngeal expansion 130-150 µm long or 45-55% of total neck length, uterus 33-41 µm long or 0.70-0.85 times the corresponding body diameter (but certainly longer), vulva transverse (V = 49-51), and tail conical elongated (45-71 µm, c = 14-22, c' = 2.0-3.2) and dorsad bent.

The positioning accuracy and precision of a head and neck immobilization device for radiation therapy of tumors in the canine skull was evaluated. Nineteen dogs with a spontaneous tumor of the head were enrolled including 12 with an intracranial mass and seven with an intranasal or maxillary tumor. Three hundred thirty-three pairs of orthogonal digital portal radiographs were analyzed to assess patient displacement in the cranial-caudal, lateral, and dorso-ventral directions. The mean systematic displacement was 0.8, 1, and 0.9 mm. The mean random displacement was 1.9, 1.6, and 1.5 mm. These values resulted in an overall displacement of 2.1 mm in the cranial-caudal direction, 1.8mm in the lateral direction, and 1.7 mm in the dorsal-ventral direction. The mean displacement value of the three dimensional (3D) vector was 2.4 mm with a standard deviation of 2.1. Ninety-five percent of all vectors were < 6.4 mm. This study quantifies the precision and accuracy of this particular positioning device. Knowing the limitations and setup variability of the system being used to set patients up for daily radiotherapy is paramount to planning and delivering appropriate radiation doses, especially as more complex treatment methods are used.

In this work we present results of the mapping on hypercube computers of some of the key steps involved in the procedure for 3D structural determination from transmission electron microscopy images. The goal is the introduction of parallel processing tools in the field of electron microscopy image processing. We show how the rich topology of the hypercube, combined with an efficient programming strategy, allows for order-of-magnitude increase in computational capacity for such time-consuming tasks as calculation of multidimensional FFT's, cross-correlation coefficients, fuzzy partitioning functionals and the filtered back-projection 3D reconstruction method.

The blast cells of 19 patients with Ph1-positive chronic granulocytic leukaemia (CGL) in blast crisis (BC) were studied by means of several techniques: morphology, cytochemistry, ultrastructure, surface markers and the enzyme terminal transferase. Cells of BC were, in most case, extremely undifferentiated by morphology and cytochemistry. Our data showed that in 80% of cases the cells in BC were myeloid and in 20% they were "lymphoblastic". The M1, M2 and M3 forms (FAB classification) were rare in CGL BC compared with acute myeloid leukaemia (AML). A megakaryoblastic type was seen in 15% of BC cases; the existence of this form could only be demonstrated by electron microscopy. The limphoblastic BC cells were, as in acute lymphoblastic leukaemia (ALL), positive with Greaves' anti-ALL serum and had elevated levels of terminal transferase. A case of a 17-year old boy presenting as ALL, reverting to chronic-phase CGL after complete remission and developing terminally a myeloid BC is described in detail. This case helps to illustrate a new form of natural history of CGL unveiled by the present study.