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1.
Braz J Biol ; 84: e281973, 2024.
Article in English | MEDLINE | ID: mdl-38836802

ABSTRACT

Agricultural management using technologies that help farmers increase productivity and reduce production costs must be promoted to ensure agricultural sustainability. The objective of the study was to achieve the pH effect of growth solution, chemical treatment, use of osmoprotector additive and mineral nitrate presence, on the activity of growth promoting bacteria, Azospirillum brasilense, and its effects on the physiological quality of seeds and wheat seedling growth. The first experiment evaluated the physiological quality of seeds and the second experiment was divided into four, evaluating the growth of wheat seedling in a hydroponic system. The experiments were prolonged in a very randomized design, with four replications. The physiological quality of the seeds was evaluated by germination tests, first germination count, length of the shoot and root and dry mass of the shoot and root. Initial growth was evaluated by quantifying the dry mass of the leaf shoot and root and the root system intervals. The pH of the solution and the presence of nitrogen did not influence the effects of inoculation of the A. brasilense bacteria. With the use of chemical treatment and osmoprotective additive, A. brasilense had no effect on the growth of wheat seedlings.


Subject(s)
Azospirillum brasilense , Culture Media , Germination , Seedlings , Triticum , Triticum/microbiology , Triticum/growth & development , Azospirillum brasilense/physiology , Seedlings/growth & development , Seedlings/microbiology , Germination/physiology , Hydrogen-Ion Concentration
2.
JAR Life ; 13: 65-72, 2024.
Article in English | MEDLINE | ID: mdl-38808150

ABSTRACT

Sarcopenia, a complex muscular condition driven by multi-systemic dysregulation and its interactions with lifestyle, physical attributes, and mental health, lacks effective drug treatments, relying primarily on non-pharmacological interventions. Fragmented approaches may prove suboptimal due to its complexity, underscoring the potential for multidomain interventions-a combination of two or more strategies to improve individual health-as a promising treatment option. This review examines the possible roles of multidomain interventions in sarcopenia, specifically addressing their effects on muscle mass and quality, muscle strength, and physical performance in older adults. While the updated literature highlights the beneficial consequences of multidomain interventions in enhancing physical performance outcomes, gaps persist in understanding their influence on the biological aspects of sarcopenia. Promising initial findings suggest changes in plasma inflammatory markers or muscle turnover networks, but further research is necessary to clarify the disease-modifying effects of multidomain intervention in sarcopenic patients.

3.
Article in English | MEDLINE | ID: mdl-38794942

ABSTRACT

BACKGROUND: To describe demographic and clinicopathological aspects of a South-American cohort of incipient oral squamous cell carcinoma patients. MATERIAL AND METHODS: A cross-sectional, observational study was performed to assess demographic and clinicopathological characteristics of incipient oral squamous cell carcinoma patients from 6 South-American institutions. RESULTS: One hundred and seven patients within the histopathological spectrum of incipient oral squamous cell carcinoma (in-situ and microinvasive) were included. Fifty-eight (54.2%) patients were men with a mean age of 60.69 years. Forty-nine (45.8%) and thirty-nine (36.5%) patients had history of tobacco and alcohol use, respectively. Clinically, most of the lesions were plaques (82.2%), ≥ 2 cm in extension (72%), affecting the lateral border of the tongue (55.1%), and soft palate (12.1%) with a mixed (white and red) appearance. Eighty-two (76.7%) lesions were predominantly white and 25 (23.3%) predominantly red. CONCLUSIONS: To the best of our knowledge, this is the largest cohort of incipient oral squamous cell carcinoma patients, which raises awareness of clinicians' inspection acuteness by demonstrating the most frequent clinical aspects of this disease, potentially improving oral cancer secondary prevention strategies.

6.
Phytomedicine ; 128: 155322, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38569291

ABSTRACT

BACKGROUND: Species adulteration is a concern in herbal products, especially when plant substitutes of lower economic value replace valuable botanicals. Styphnolobium japonicum is well known as a potential adulterant of Ginkgo biloba, which is one of the most demanded medicinal plants due to its wide use in pharmaceuticals, food supplements, and traditional medicine. Despite bearing some resemblance to ginkgo's flavonol composition, S. japonicum lacks many of G. biloba's desired therapeutic properties. To prevent adulteration practices, it is crucial to implement rigorous quality control measures, including fast and simple diagnostic tools that can be used on-field. PURPOSE: This study aims to develop for the first time a species-specific loop-mediated isothermal amplification (LAMP) method for the fast identification of S. japonicum in ginkgo-containing products. METHODS: A set of four specific primers (SjF3, SjB3, SjFIP, and SjBIP) and loop primers (SjLF and SjLB) were designed for a LAMP based assay using the 5.8S partial sequence and the internal transcribed spacer 2 of nuclear ribosomal DNA of S. japonicum. RESULTS: The successful amplification of the LAMP assay was inspected through visual detection, with the highest intensity recorded at the optimal conditions set at 68 °C for 40 min. The primers showed high specificity and were able to accurately discriminate S. japonicum from G. biloba and 49 other species of medicinal plants. Furthermore, the proposed LAMP assay proved to be fast, selective, and highly sensitive, as demonstrated by the absolute and relative limits of detection, which were reached at 0.5 pg for S. japonicum DNA and 0.01 % S. japonicum in G. biloba, respectively. CONCLUSIONS: This novel approach allows easy identification and discrimination of S. japonicum as a potential adulterant of G. biloba, thus being a useful tool for quality control. Compared to chromatographic or PCR-based methods, the assay proved to be fast, sensitive and did not require expensive equipment, thus offering the possibly usage in field analysis.


Subject(s)
Drug Contamination , Ginkgo biloba , Molecular Diagnostic Techniques , Nucleic Acid Amplification Techniques , Ginkgo biloba/chemistry , Nucleic Acid Amplification Techniques/methods , Drug Contamination/prevention & control , DNA Primers , DNA, Plant/genetics , Plants, Medicinal/chemistry , Sophora japonica
7.
Benef Microbes ; 15(2): 211-225, 2024 Mar 11.
Article in English | MEDLINE | ID: mdl-38688481

ABSTRACT

Enterococcus faecium SF68 (SF68) is a well-known probiotic with a long history of safe use. Recent changes in the taxonomy of enterococci have shown that a novel species, Enterococcus lactis, is closely related with E. faecium and occurs together with other enterococci in a phylogenetically well-defined E. faecium species group. The close phylogenetic relationship between the species E. faecium and E. lactis prompted a closer investigation into the taxonomic status of E. faecium SF68. Using phylogenomics and ANI, the taxonomic analysis in this study showed that probiotic E. faecium SF68, when compared to other E. faecium and E. lactis type and reference strains, could be re-classified as belonging to the species E. lactis. Further investigations into the functional properties of SF68 showed that it is potentially capable of bacteriocin production, as a bacteriocin gene cluster encoding the leaderless bacteriocin EntK1 together with putative Lactococcus lactis bacteriocins LsbA, and LsbB-like putative immunity peptide (LmrB) were found located in an operon on plasmid pF9. However, bacteriocin expression was not studied. Competitive exclusion experiments in co-culture over 7 days at 37 °C showed that the probiotic SF68 could inhibit the growth of specific E. faecium and Listeria monocytogenes strains, while showing little or no inhibitory activity towards an entero-invasive Escherichia coli and a Salmonella Typhimurium strain, respectively. In cell culture experiments with colon carcinoma HT29 cells, the probiotic SF68 was also able to strain-specifically inhibit adhesion and/or invasion of enterococcal and L. monocytogenes strains, while such adhesion and invasion inhibition effects were less pronounced for E. coli and Salmonella strains. This study therefore provides novel data on the taxonomy and functional properties of SF68, which can be reclassified as Enterococcus lactis SF68, thereby enhancing the understanding of its probiotic nature.


Subject(s)
Bacteriocins , Enterococcus faecium , Phylogeny , Probiotics , Enterococcus faecium/genetics , Enterococcus faecium/classification , Enterococcus faecium/physiology , Bacteriocins/genetics , Bacteriocins/metabolism , Humans , Antibiosis , Plasmids/genetics , Multigene Family , HT29 Cells
8.
Reumatismo ; 76(1)2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38523582

ABSTRACT

OBJECTIVE: To report cross-sectionally serum levels of 25-hydroxyvitamin D [25(OH)D] in women living in Italy within 12 months from breast cancer (BC) diagnosis. METHODS: Baseline data were obtained from 394 women diagnosed with primary BC, enrolled from 2016 to 2019 in a lifestyle trial conducted in Italy. Subjects' characteristics were compared between two 25(OH)D concentrations (hypovitaminosis D<20 and ≥20 ng/mL) with the Chi-squared test or Fisher's exact test for small-expected counts. Using multiple logistic regression-adjusted models, we estimated odds ratios (ORs) of hypovitaminosis D with 95% confidence intervals (CIs) in the total sample and in the unsupplemented subgroup. RESULTS: Hypovitaminosis D was found in 39% of all subjects, 60% in unsupplemented subjects, and 10% in supplemented subjects. Increasing ORs of hypovitaminosis D were found with increasing body mass index, 25-30, >30, and ≥35 versus <25 kg/m2 (ORs: 2.50, 4.64, and 5.81, respectively, in the total cohort and ORs: 2.68, 5.38, and 7.08 in the unsupplemented); living in the most southern Italian region (OR 2.50, 95%CI 1.22-5.13); and with hypertriglyceridemia (OR 2.46; 95%CI 1.16-5.22), chemotherapy history (OR 1.86, 95%CI 1.03-3.38), and inversely with anti-estrogenic therapy (OR 0.43, 95%CI 0.24-0.75) in the total sample. CONCLUSIONS: Hypovitaminosis D in women recently diagnosed with BC and participating in a lifestyle trial in Italy was widespread and highest with obesity, hypertriglyceridemia, and chemotherapy use. Considering that hypovitaminosis D is a risk factor for lower efficacy of bone density treatments and possibly BC mortality, our results suggest the need to promptly address and treat vitamin D deficiency.


Subject(s)
Breast Neoplasms , Hypertriglyceridemia , Vitamin D Deficiency , Vitamin D , Female , Humans , Breast Neoplasms/epidemiology , Breast Neoplasms/complications , Hypertriglyceridemia/complications , Italy/epidemiology , Life Style , Risk Factors , Vitamin D/analogs & derivatives , Vitamin D Deficiency/epidemiology
9.
J Hosp Infect ; 148: 62-76, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38554808

ABSTRACT

Carbapenem-resistant Klebsiella pneumoniae (CR-KP) are a public health concern, causing infections with a high mortality rate, limited therapeutic options and challenging infection control strategies. In Portugal, the CR-KP rate has increased sharply, but the factors associated with this increase are poorly explored. In order to address this question, phylogenetic and resistome analysis were used to compare the draft genomes of 200 CR-KP isolates collected in 2017-2019 from five hospitals in the Lisbon region, Portugal. Most CR-KP belonged to sequence type (ST) 13 (29%), ST17 (15%), ST348 (13%), ST231 (12%) and ST147 (7%). Carbapenem resistance was conferred mostly by the presence of KPC-3 (74%) or OXA-181 (18%), which were associated with IncF/IncN and IncX plasmids, respectively. Almost all isolates were multi-drug resistant, harbouring resistance determinants to aminoglycosides, beta-lactams, trimethoprim, fosfomycin, quinolones and sulphonamides. In addition, 11% of isolates were resistant to colistin. Colonizing and infecting isolates were highly related, and most colonized patients (89%) reported a previous hospitalization. Moreover, among the 171 events of cross-dissemination identified by core genome multi-locus sequence typing data analysis (fewer than five allelic differences), 41 occurred between different hospitals and 130 occurred within the same hospital. The results suggest that CR-KP dissemination in the Lisbon region results from acquisition of carbapenemases in mobile genetic elements, influx of CR-KP into the hospitals by colonized ambulatory patients, and transmission of CR-KP within and between hospitals. Prudent use of carbapenems, patient screening at hospital entry, and improvement of infection control are needed to decrease the burden of CR-KP infection in Portugal.


Subject(s)
Carbapenem-Resistant Enterobacteriaceae , Genome, Bacterial , Hospitals , Klebsiella Infections , Klebsiella pneumoniae , Portugal/epidemiology , Humans , Klebsiella Infections/microbiology , Klebsiella Infections/epidemiology , Klebsiella pneumoniae/genetics , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/isolation & purification , Klebsiella pneumoniae/classification , Carbapenem-Resistant Enterobacteriaceae/genetics , Carbapenem-Resistant Enterobacteriaceae/drug effects , Carbapenem-Resistant Enterobacteriaceae/isolation & purification , Carbapenem-Resistant Enterobacteriaceae/classification , Aged , Middle Aged , Male , Anti-Bacterial Agents/pharmacology , Female , Carbapenems/pharmacology , Aged, 80 and over , Cross Infection/microbiology , Cross Infection/epidemiology , Adult , Plasmids/genetics , Drug Resistance, Multiple, Bacterial/genetics , Phylogeny , Young Adult , Microbial Sensitivity Tests , Adolescent
11.
Braz J Biol ; 83: e275439, 2024.
Article in English | MEDLINE | ID: mdl-38422263

ABSTRACT

Visceral Leishmaniasis is included among the neglected tropical diseases, being directly related to conditions of social vulnerability, in urban environments, dogs act as important reservoirs. The aim of the study was to evaluate the distribution of dogs, related risk factors and identify of volatile organic compounds from infected dogs. Peripheral blood samples from 72 dogs were collected for detection using the ELISA test, in addition to hair samples for analysis by GC-MS. Of the evaluated dogs, 13 (18.05%/72) were reactive for canine VL, seven in Aracaju and six in Propriá. Factors related to vegetation, age, place where the dog stays and free access to the street, were associated with a greater chance of the dog becoming infected. Fifty-three compounds were identified from ten canine hair samples, among which 2-butoxyethanol, benzaldehyde, decane, 2-phenylacetaldehyde, nonan-1-ol, 2-phenoxyethanol, nonanoic acid, 8-heptadecene and eicosane were found in seropositive dogs for leishmaniasis. The guardian's posture has been increasingly important, requiring more attention to the dog's health and actions aimed at environmental management in an attempt to reduce cases of canine VL in the state. Even though the identified VOCs have not been associated with leishmanial infection, it is of great use for understanding canine hair substances.


Subject(s)
Dog Diseases , Leishmaniasis, Visceral , Animals , Dogs , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/epidemiology , Leishmaniasis, Visceral/veterinary , Dog Diseases/diagnosis , Dog Diseases/epidemiology , Spatial Analysis , Brazil , Enzyme-Linked Immunosorbent Assay
12.
Biochim Biophys Acta Bioenerg ; 1865(2): 149033, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38368917

ABSTRACT

Mitochondrial and thus cellular energetics are highly regulated both thermodynamically and kinetically. Cellular energetics is of prime importance in the regulation of cellular functions since it provides ATP for their accomplishment. However, cellular energetics is not only about ATP production but also about the ability to re-oxidize reduced coenzymes at a proper rate, such that the cellular redox potential remains at a level compatible with enzymatic reactions. However, this parameter is not only difficult to assess due to its dual compartmentation (mitochondrial and cytosolic) but also because it is well known that most NADH in the cells is bound to the enzymes. In this paper, we investigated the potential relevance of mitochondrial quinones redox state as a marker of mitochondrial metabolism and more particularly mitochondrial redox state. We were able to show that Q2 is an appropriate redox mediator to assess the mitochondrial quinone redox states. On isolated mitochondria, the mitochondrial quinone redox states depend on the mitochondrial substrate and the mitochondrial energetic state (phosphorylating or not phosphorylating). Last but not least, we show that the quinones redox state response allows to better understand the Krebs cycle functioning and respiratory substrates oxidation. Taken together, our results suggest that the quinones redox state is an excellent marker of mitochondrial metabolism.


Subject(s)
Benzoquinones , Mitochondria , Quinones , Oxidation-Reduction , Mitochondria/metabolism , Quinones/metabolism , Adenosine Triphosphate/metabolism
13.
Sci Data ; 11(1): 129, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38272945

ABSTRACT

One of the most critical steps for accurate taxonomic identification in DNA (meta)-barcoding is to have an accurate DNA reference sequence dataset for the marker of choice. Therefore, developing such a dataset has been a long-term ambition, especially in the Viridiplantae kingdom. Typically, reference datasets are constructed with sequences downloaded from general public databases, which can carry taxonomic and other relevant errors. Herein, we constructed a curated (i) global dataset, (ii) European crop dataset, and (iii) 27 datasets for the EU countries for the ITS2 barcoding marker of vascular plants. To that end, we first developed a pipeline script that entails (i) an automated curation stage comprising five filters, (ii) manual taxonomic correction for misclassified taxa, and (iii) manual addition of newly sequenced species. The pipeline allows easy updating of the curated datasets. With this approach, 13% of the sequences, corresponding to 7% of species originally imported from GenBank, were discarded. Further, 259 sequences were manually added to the curated global dataset, which now comprises 307,977 sequences of 111,382 plant species.


Subject(s)
DNA Barcoding, Taxonomic , Tracheophyta , DNA, Plant/genetics , Phylogeny , Plants/genetics , Sequence Analysis, DNA
14.
AIDS ; 38(1): 123-125, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38061022

ABSTRACT

OBJECTIVE: The study analyzed people with HIV (PWH) measles seroprevalence and response to MMR booster given to seronegative individuals. DESIGN: A prospective cohort study with four groups: vertically (v-HIV), horizontally infected (h-HIV) individuals, and two control groups. An MMR booster was offered to seronegative individuals. RESULTS: Measles seropositivity and IgG antibodies were significantly lower in v-HIV than in the other groups. All measles seronegative patients responded to booster. CONCLUSION: An MMR booster must be sought during adolescence in vertically PWH.


Subject(s)
HIV Infections , Measles , Humans , Adolescent , Young Adult , Prospective Studies , Seroepidemiologic Studies , HIV Infections/epidemiology , Antibodies, Viral , Measles/epidemiology , Vaccination
15.
Front Immunol ; 14: 1273837, 2023.
Article in English | MEDLINE | ID: mdl-38077336

ABSTRACT

Introduction: The cyclic nucleotide cyclic adenosine monophosphate (cAMP) is a ubiquitous second messenger, which is known to play an important anti-inflammatory role. Astrocytes in the central nervous system (CNS) can modulate inflammation but little is known about the significance of cAMP in their function. Methods: We investigated cAMP dynamics in mouse olfactory bulb astrocytes in brain slices prepared from healthy and experimental autoimmune encephalomyelitis (EAE) mice. Results: The purinergic receptor ligands adenosine and adenosine triphosphate (ATP) both induced transient increases in cAMP in astrocytes expressing the genetically encoded cAMP sensor Flamindo2. The A2A receptor antagonist ZM241385 inhibited the responses. Similar transient increases in astrocytic cAMP occurred when olfactory receptor neurons were stimulated electrically, resulting in ATP release from the stimulated axons that increased cAMP, again via A2A receptors. Notably, A2A-mediated responses to ATP and adenosine were not different in EAE mice as compared to healthy mice. Discussion: Our results indicate that ATP, synaptically released by afferent axons in the olfactory bulb, is degraded to adenosine that acts on A2A receptors in astrocytes, thereby increasing the cytosolic cAMP concentration. However, this pathway is not altered in the olfactory bulb of EAE mice.


Subject(s)
Encephalomyelitis, Autoimmune, Experimental , Mice , Animals , Astrocytes/metabolism , Olfactory Bulb/metabolism , Cyclic AMP/metabolism , Adenosine/metabolism , Adenosine Triphosphate/metabolism , Receptors, Purinergic P1/metabolism
16.
Reumatismo ; 75(4)2023 Dec 19.
Article in English | MEDLINE | ID: mdl-38115776

ABSTRACT

We report the case of a 54-year-old woman with antineutrophilic cytoplasmic antibody-negative eosinophilic granulomatosis with polyangiitis presenting with mononeuritis multiplex, intestinal hemorrhage, cardiomyopathy, fever, and worsening asthma symptoms. She was initially treated with steroids and cyclophosphamide but eventually required rituximab to control a vasculitis flare. However, her asthmatic symptoms did not improve, despite attaining vasculitis remission. Symptoms abated only after the treatment transition to mepolizumab. After a 1-year interval, there were no further episodes of asthma exacerbation and no requirement for systemic steroid therapy. This report reinforces the use of rituximab for induction and maintenance of remission in patients with eosinophilic granulomatosis with polyangiitis and predominant vasculitic manifestations, whereas mepolizumab demonstrated better control of the persistent eosinophilic manifestations, ensuing sustained remission and improved quality of life.


Subject(s)
Asthma , Churg-Strauss Syndrome , Granulomatosis with Polyangiitis , Female , Humans , Middle Aged , Rituximab/therapeutic use , Immunosuppressive Agents , Churg-Strauss Syndrome/drug therapy , Granulomatosis with Polyangiitis/complications , Granulomatosis with Polyangiitis/drug therapy , Quality of Life , Treatment Outcome
17.
Mar Pollut Bull ; 195: 115450, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37666136

ABSTRACT

Stochastic simulations of virtual oil spills from ships were performed for the Adriatic Sea over 2017-2020, applying the European Marine Observation and Data Network vessel densities as a proxy for starting locations of operational spillage. The MEDSLIK-II oil spill model was run using high-resolution currents provided by the Copernicus Marine Service and the European Centre for Medium-Range Weather Forecasts winds. Chronic exposure to operational oil spills was reported in terms of hazard indices for five vessel groups: pleasure and passenger ships, cargo and service vessels, the fishing fleet, tankers, and other ships. The northernmost Adriatic expectedly showed the highest hazard values, including the areas of Trieste and Venice, where cargo and service ships were the dominant polluters. The Croatian coastal waters were more chronically polluted than the Italian coastal waters; the predominant contribution was from coastwise pleasure and passenger ships.

18.
Braz J Biol ; 83: e270740, 2023.
Article in English | MEDLINE | ID: mdl-37585926

ABSTRACT

Logging and agricultural exploitation have led to the degradation of Araucaria Forest remnants and the alteration of its last preserved patches. This forest typology contains many endangered plant species, as is the case of the tree Oreopanax fulvus Marchal. To support conservation of this species and understand how different landscape matrices can influence its populations, we evaluated the demographic structure and spatial distribution of O. fulvus in two Araucaria Forest remnants in Paraná state. We delimited two plots (urban and rural population), each with 1 ha, subdivided them into 100 subplots (10 x 10 m), and recorded diameter at ground level (DGL), height, and coordinates of two post-germinative developmental stage of individuals. In each subplot, we measured slope, luminosity, and canopy height. We used Ripley's K function analysis to describe distribution patterns of the species and the spatial relationship between mature and juvenile trees. We performed correlations between abundance and environmental and structural variables of the O. fulvus populations. Abundance varied between remnants, from 183 individuals/ha (12 mature and 171 juvenile) to 1306 individuals/ha (10 and 1296). The remnants varied in abundance and plant frequency. The species showed an investment in seedling banks. Most juvenile had DGL up to 3.0 cm and height up to 1.0 m and presented aggregated spatial distribution, while adults had random distribution. In the rural population juvenile abundance were correlated with canopy height (positively) and distance to mature trees (negatively). The slope was correlated for both sites, but oppositely, indicating that other factors might have interfered in the regeneration abundance. The urban remnant showed a high abundance of this endangered species, calling attention for potential studies in urban arborization, management and conservation of these remnants.


Subject(s)
Endangered Species , Rural Population , Humans , Animals , Brazil , Forests , Trees , Population Density
19.
Microb Ecol ; 86(4): 2655-2665, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37480517

ABSTRACT

Trypanosomatids form a group of high prevalence protozoa that parasitise honey bees, with Lotmaria passim as the predominant species worldwide. However, the knowledge about the ecology of trypanosomatids in isolated areas is limited. The Portuguese archipelagos of Madeira and Azores provide an interesting setting to investigate these parasites because of their geographic isolation, and because they harbour honey bee populations devoid of two major enemies: Varroa destructor and Nosema ceranae. Hence, a total of 661 honey bee colonies from Madeira and the Azores were analysed using different molecular techniques, through which we found a high prevalence of trypanosomatids despite the isolation of these islands. L. passim was the predominant species and, in most colonies, was the only one found, even on islands free of V. destructor and/or N. ceranae with severe restrictions on colony movements to prevent the spread of them. However, islands with V. destructor had a significantly higher prevalence of L. passim and, conversely, islands with N. ceranae did not shown any significant correlation with the trypanosomatid. Crithidia bombi was detected in Madeira and on three islands of the Azores, almost always coincident with L. passim. By contrast, Crithidia mellificae was not detected in any sample. A high-throughput sequencing analysis distinguished two main haplotypes of L. passim, which accounted for 98% of the total sequence reads. This work suggests that L. passim and C. bombi are parasites that have been associated with honey bees predating the spread of V. destructor and N. ceranae.


Subject(s)
Beekeeping , Trypanosomatina , Animals , Bees , Trypanosomatina/genetics , Trypanosomatina/parasitology , Crithidia/genetics , Crithidia/parasitology , Symbiosis , Azores
20.
J Econ Entomol ; 116(4): 1352-1359, 2023 08 10.
Article in English | MEDLINE | ID: mdl-37262318

ABSTRACT

The Colorado potato beetle, Leptinotarsa decemlineata (Say) ([Coleoptera]: [Chrysomelidae]), is the most important defoliator of solanaceous plants worldwide. This insect displays a notorious ability in adapting to biological and synthetic insecticides, although in some cases this adaptation carries relevant fitness costs. Insecticidal gene silencing by RNA interference is a novel mode of action pesticide against L. decemlineata that is activated by ingestion of a double stranded RNA (dsRNA) targeting a vital L. decemlineata gene. We previously reported laboratory selection of a > 11,000-fold resistant strain of L. decemlineata to a dsRNA delivered topically to potato leaves. In this work, we tested the existence of fitness costs in this dsRNA-resistant colony by comparing biological parameters to the parental strain and an additional susceptible reference strain. Biological parameters included length of egg incubation period, number of eggs per clutch, egg viability, larval viability, length of larval and pupal periods, adult emergence, number of eggs laid per day, sex ratio, and adult longevity. Comparisons between the 3 beetle strains detected no fitness costs associated with resistance to dsRNA. This information is important to guide effective insect resistance management plans for dsRNA insecticides against L. decemlineata applied topically to potato leaves.


Subject(s)
Coleoptera , Insecticides , Solanum tuberosum , Animals , Insecticides/pharmacology , RNA, Double-Stranded/genetics , Larva , RNA Interference , Solanum tuberosum/genetics
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