Geographical Origin Research Articles

Classifying PDO Kalamata Olive Oil from Geographic Origins of the Messenia Region based on Statistical Machine Learning

Kalamata is a smart city located in southeastern Greece in the Mediterranean basin and it is the capital of the Messenia regional unit. It is known for the famous Protected Designation of Origin (PDO) Kalamata olive oil produced mainly from the Koroneiki olive variety. The PDO Kalamata olive oil, established by Council regulation (EC) No 510/2006, owes its quality and special characteristics to the geographical environment, olive tree variety, and human factor. The PDO Kalamata olive oil is produced exclusively in the regional unit of Messenia, being the main profit of local farmers. However, soil chemical composition, microclimates, and agronomic factors are changed within the Messenia spatial area leading to differentiation of PDO Kalamata olive oil characteristic. In this paper, we use statistical machine learning algorithms to determine the geographical origin of Kalamata olive oil at PDO level based on synchronous excitation−emission fluorescence spectroscopy of olive oils. Evaluations of the statistical models are promising for differentiating the origin of PDO Kalamata olive oil with high values of prediction accuracy thus enabling companies that process and bottle kalamata olive oil to choose olive oil from a specific region of Messenia that fulfills certain characteristics. Concretely, the current research effort focuses on a specific olive oil variety within a limited geographic region. Intuitively, future research should also focus on validation of the proposed methodology to other olive oil varieties and production areas.

Unexpected effect of geographic origin on post‐translocation survival in a long‐lived reptile, the gopher tortoise

AbstractMitigation translocations move wildlife from specific areas due to conflict with humans over land use at the site. A critical decision when carrying out mitigation translocation is the acceptable distance across which animals can be moved. This decision trades off logistical expediency of unrestricted translocation with the risk of reducing translocation success due to environmental mismatch between origin and translocation site conditions. In this study, we used a large dataset of 502 individually identifiable carcasses to examine the role of geographic origin and translocation distance in the relative survival of 2822 translocated subadult and adult gopher tortoises (Gopherus polyphemus), a species experiencing large‐scale mitigation translocation, at a recipient site in the Florida panhandle, USA. We hypothesized that if climate or habitat differences between the origin and translocation site influenced survival, tortoises translocated from within the Florida panhandle would have the highest survival. To the contrary, we found that survival slightly increased with increasing climatic difference between origin and recipient site, driven by higher survival of tortoises coming from central Florida sites compared to those from the panhandle and north Florida. This suggests that environmental mismatch due to long‐distance translocation is not a main driver of mortality. These models also indicated an effect of season, with a survival advantage to tortoises translocated in the spring and late fall, relative to summer translocations, and a negative effect of initial density on survival. Finally, we also estimated the upper bound on annual survival in three well‐monitored groups to be quite low (92–95%) for several years following release, suggesting caution when considering large translocated populations to be viable without first assessing adult survival. Our unexpected results highlight the importance of investigating species‐specific sensitivities to translocation distances and indicate the limitations of assumed linear effects of translocation distance on outcomes.

Forensic Geochemistry Reveals International Ship Dumping as a Source of New Oil Spill in Brazil's Coastline (Bahia) in Late 2023.

In the present study, we applied forensic geochemistry to investigate the origin and fate of spilled oils like tarballs stranded at the beaches of Bahia, in northeastern Brazil, in September 2023, based on their fingerprints. Saturated and aromatic compounds were assessed by gas chromatography, and the oceanic surface circulation patterns were deciphered to determine the geographic origin of the spill. Contamination by petroleum represents an enormous threat to the unique, species-rich ecosystems of the study area. The geochemical fingerprint of the oil spilled in 2023 did not correlate with those of previous events, including the one in 2019, the one in early 2022 in Ceará, and an extensive spill across the Brazilian Northeast in late 2022. However, the fingerprint did correlate with crude oils produced by Middle Eastern countries, most likely Kuwait. The oil of the 2023 spill had a carbonate marine origin from early mature source rocks. These findings, together with the moderate weathering of the 2023 tarballs and the ocean circulation patterns at the time of the event, indicate that the oil was discharged close to the shore of Brazil, to the east or southeast of Salvador, by a tanker on an international route in the South Atlantic.

Influence of geographical origin in the physical and bioactive parameters of single origin dark chocolate

AbstractDark chocolate presents exclusive characteristics that make it a food product with worldwide consumption and also as an ingredient in several food industries. Although chocolate is an energy-dense food, it is also rich in bioactive compounds and recent studies have demonstrated health benefits from a moderate consumption. Therefore, the quantification of the bioactive compounds of different types of cocoa, from different geographical origins, is of great importance to recognize the importance of single origin dark chocolate from the nutritional point of view. Dark chocolate produced from Amelonado variety presented higher values of hardness (5592 g), plastic viscosity (2.87 Pa.s) and yield value (12.91 Pa). Both dark chocolates from Peru, Piura Blanco and Chuncho, presented higher results in total phenolic content, total antioxidant capacity, caffeine and vitamin E. Additionally, sample Piura Blanco presented a higher content of theobromine (720.7 mg/100 g), lactic acid (1153.2 mg/100 g), succinic acid (679.4 mg/100 g) and oxalic acid (468.5 mg/100 g). On the other hand, chocolate from São Tomé presented a higher content of sucrose (38.22%) and SFA (62.38% of total fat). The results obtained demonstrate the existence of heterogeneity in cocoa varieties, supporting decision-makers in the selection of the most suitable cocoa for specific market needs.

Differentiation of Polygonatum Cyrtonema Hua from Different Geographical Origins by near-Infrared Spectroscopy with Chemometrics.

The identification of the geographical origin of Polygonatum cyrtonema Hua is of particular importance because the quality and market value of Polygonatum cyrtonema Hua from different production areas are highly variable due to differences in the growing environment and climatic conditions. This study utilized near-infrared spectra (NIR) of Polygonatum cyrtonema Hua (n = 400) to develop qualitative models for effective differentiation of Polygonatum cyrtonema Hua from various regions. The models were produced under different conditions to distinguish the origins distinctly. Ten pre-processing methods have been used to pre-process the original spectra (OS) and to select the most optimal spectral pre-processing method. Principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and orthogonal partial least squares discriminant analysis (OPLS-DA) were employed to determine appropriate models. For simplicity, the pretreated full spectrum was calculated by different wavelength selection methods, and the four most significant variables were selected as discriminant indicator variables. The results show that Polygonatum cyrtonema Hua from different regions can be effectively distinguished using spectra from a series of samples analyzed by OPLS-DA. The accuracy of the OPLS-DA model is also satisfactory, with a good differentiation rate. The study findings indicate the feasibility of using spectroscopy in combination with multivariate analysis to identify the geographical origins of Polygonatum cyrtonema Hua. The utilization of near-infrared spectroscopy combined with chemometrics exhibits high efficacy in discerning the provenance of herbal medicines and foods, thereby facilitating quality assurance measures.

Potential of MALDI-TOF MS biotyping to detect deltamethrin resistance in the dengue vector Aedes aegypti.

Insecticide resistance in mosquitoes is spreading worldwide and represents a growing threat to vector control. Insecticide resistance is caused by different mechanisms including higher metabolic detoxication, target-site modification, reduced penetration and behavioral changes that are not easily detectable with simple diagnostic methods. Indeed, most molecular resistance diagnostic tools are costly and labor intensive and then difficult to use for routine monitoring of insecticide resistance. The present study aims to determine whether mosquito susceptibility status against the pyrethroid insecticides (mostly used for mosquito control) could be established by the protein signatures of legs and/or thoraxes submitted to MALDI-TOF Mass Spectrometry (MS). The quality of MS spectra for both body parts was controlled to avoid any bias due to unconformity protein profiling. The comparison of MS profiles from three inbreeds Ae. aegypti lines from French Guiana (IRF, IR03, IR13), with distinct deltamethrin resistance genotype / phenotype and the susceptible reference laboratory line BORA (French Polynesia), showed different protein signatures. On both body parts, the analysis of whole protein profiles revealed a singularity of BORA line compared to the three inbreeding lines from French Guiana origin, suggesting that the first criteria of differentiation is the geographical origin and/or the breeding history rather than the insecticide susceptibility profile. However, a deeper analysis of the protein profiles allowed to identify 10 and 11 discriminating peaks from leg and thorax spectra, respectively. Among them, a specific peak around 4870 Da was detected in legs and thoraxes of pyrethroid resistant lines compared to the susceptible counterparts hence suggesting that MS profiling may be promising to rapidly distinguish resistant and susceptible phenotypes. Further work is needed to confirm the nature of this peak as a deltamethrin resistant marker and to validate the routine use of MS profiling to track insecticide resistance in Ae. aegypti field populations.

Marsh-orchids of Canada: long-standing mysteries partially solved

SummaryBetween 1959 and 1988, three populations of purple-flowered terrestrial orchids attributable to Dactylorhiza subgenus Dactylorhiza were discovered in Canada. The populations at Timmins, Ontario, and St John's, Newfoundland were strongly marked on both flowers and leaves, in contrast with the anthocyanin-deficient population at Tilt Cove, Newfoundland. All three populations have since experienced a wide range of taxonomic assignments; debates are also ongoing regarding their origin and most appropriate conservation status. Here, we address these questions by combining detailed in situ morphometric analyses based on 52 characters with allozyme profiles and data from nrITS, 15 plastid microsatellites and seven nuclear microsatellites. The allozyme data alone are sufficient to both confirm allopolyploidy and categorically refute past assignments of these populations to D. incarnata, D. maculata, D. fuchsii, D. majalis or D. purpurella. Several morphometric characters, nuclear microsatellites and nrITS all reliably distinguish each of the three study populations, whereas the two sampled subpopulations from St John's proved near-identical morphologically. In contrast, morphological variation within each of the three populations is strikingly low, particularly in characters other than those influenced by plant vigour. Similarly, compared with 14 European populations, the three Canadian populations proved genetically impoverished (two were near-invariant) and likely experienced recent, extreme genetic bottlenecks during establishment. The three populations differ substantially, both morphologically and molecularly, therefore probably representing independent immigration events. Although clearly attributable to D. praetermissa, all three populations deviate significantly in morphology and DNA data from comparable populations sampled across Europe, preventing identification of their precise geographic origins. Any attempt to determine their mode or origin — through natural long-distance transport, or accidental or deliberate introduction by humans – is challenged to explain why three lineages of a single European Marsh-orchid species, each in different ways atypical of that species, arrived independently in North America whereas no other European dactylorchid species has become established there.

Establishment of a Multilocus Sequence Typing Scheme for the Characterization of Avibacterium paragallinarum

Infectious coryza is an acute respiratory infection caused by Avibacterium paragallinarum, which is widely distributed throughout the world. However, there is no effective molecular typing scheme to obtain basic knowledge about the Av. paragallinarum population structure. This study aimed to develop a multilocus sequence typing (MLST) scheme for Av. paragallinarum that allows for the worldwide comparison of sequence data. For this purpose, the genetic variability of 59 Av. paragallinarum strains from different geographical origins and serovars was analyzed to identify correlations. The MLST scheme was developed using seven conserved housekeeping genes, which identified eight STs that clustered all of the strains into three evolutionary branches. The analytical evaluation of the clone group relationship between the STs revealed two clone complexes (CC1 and CC2) and three singletons (ST2, ST5, and ST6). Most of the isolates from China belonged to ST1 and ST3 in CC1. ST8 from Peru and ST7 from North America together formed CC2. Our results showed that the Av. paragallinarum strains isolated from China had a distant genetic relationship with CC2, indicating strong regional specificity. The MLST scheme established in this study can monitor the dynamics and genetic differences of Av. paragallinarum transmission.

Winter-ground microhabitat use by differently coloured phenotypes affects return rate in a long-distance migratory bird.

Migratory bird populations are declining globally at alarming rates. Non-breeding site conditions affect breeding populations, but generalising non-breeding habitat conditions over large spatial regions cannot address potential fine-scale differences across landscapes or local populations. Plumage characteristics can mediate the effects of environmental conditions on individual fitness. However, whether different phenotypes use distinctive non-breeding sites, and whether they respond to non-breeding site conditions differently remains largely unknown. Stable isotopes (δ13C, δ15N, δ2H) of inert tissues are useful to infer habitat characteristics and geographic origins where those tissues were grown. We collected winter-grown feathers from pied flycatchers (Ficedula hypoleuca) on their breeding grounds over several years from males whose dorsal plumage colouration ranged continuously from brown to black and assessed their stable isotope values as proxies of local habitat conditions. Based on feather δ2H profiles we found that browner males spent their non-breeding season in drier habitats than black males. Assignment to origin analysis shows potential regional non-breeding ground separation between differently coloured males. High within-individual repeatability of both δ13C and δ15N indicate the pied flycatcher males return yearly to similar areas. Blacker males were more likely to return to the breeding grounds after dry years compared with brown males. The opposite was found in wet years. Our study demonstrates that different phenotypes are exposed to different non-breeding site conditions which can differentially affect individual survivorship. This has important ramifications for population dynamics under predicted climate change scenarios where especially brown phenotype pied flycatcher males may be under a risk of decreasing.

Seroprevalence and Risk Factors of Toxoplasma gondii Infection of Cattle and Goats in Farms of Hunan Province, China.

Background: Toxoplasmosis is one of the most widespread foodborne parasitic zoonoses caused by the obligate intracellular protozoan Toxoplasma gondii. Although a number of studies have reported on the seroprevalence and risk factors of T. gondii infection in ruminants in China, information about T. gondii infection in cattle in Hunan province of China is not available. Material and Methods: Sera of 985 cattle and 1147 goats were examined for the presence of specific antibodies against T. gondii using the indirect hemagglutination test. Some risk factors related to the presence of cats, herd size, gender, age, and geographical origin were determined using a binary logistic regression. Results: Specific IgG against T. gondii were detected in 8.3% (82/985) and 13.3% (153/1147) of the cattle and goats, respectively. Based on statistical analysis, the presence of cats and gender were considered important risk factors for T. gondii infection in cattle and goats in the farms in this study (P < 0.05). Conclusion: Our results provide a baseline for future prevention and control of T. gondii infection in cattle and goats in Hunan province, subtropical China. This is the first report of T. gondii seroprevalence in cattle in Hunan province, China.

Effect of seed's geographical origin on cactus oil physico-chemical characteristics, oxidative stability, and antioxidant activity

The aim of this study was the valorisation of cactus (or prickly pear, Opuntia ficus-indica) seeds growing in six different regions of Morocco. Moisture, proteins, lipids profile, total polyphenols content, oxidative stability, and antioxidant activity were investigated. The Folin-Ciocalteu test highlighted the abundant presence of phenolic compounds (165 to 225 mg EAG/100 g of extract) and a significant antioxidant capacity against DPPH free radicals. The seeds contained protein (7–9.25%) and lipids (2.7–5%). Cactus oil quality indices such as acidity and peroxide value were below 1.2% and 10 mEq.O2/kg, respectively. GC analysis revealed that linoleic and oleic acid percentages ranged from 57.1 to 63.8%, and 13.5 to 18.7%, respectively. Cactus seed oil was rich in tocopherols (500–680 mg/kg) and phytosterols (8000–11,100 mg/kg) with a predominance of γ-tocopherols and β-sitosterol. Triacylglycerols, fatty acids and sterols composition showed small variation depending on the geographical origin, while the individual tocopherol profile was significantly influenced.

Investigating the Impact of Origins on the Quality Characteristics of Celery Seeds Based on Metabolite Analysis through HS-GC-IMS, HS-SPME-GC-MS and UPLC-ESI-MS/MS

Celery seeds contain various bioactive compounds and are commonly used as a spice and nutritional supplement in people’s daily lives. The quality of celery seeds sold on the market varies, and their regions of production are unclear. This study evaluated the metabolites of Chinese celery seeds from three production regions using HS-SPME-GC-MS, HS-GC-IMS, and UPLC-ESI-MS/MS. The results indicate that GC-IMS analysis obtained a metabolic profile different from that detected using GC-MS. Terpenoids, polyphenols, coumarins, and phthalides are the main bioactive compounds in celery seeds. The production region significantly affects the metabolic characteristics of celery seeds. Based on GC-MS data, GC-IMS data, and LC-MS data, the variation analysis screened 6, 12, and 8 metabolites as potential characteristic metabolites in celery seeds related to the production region, respectively. According to the aromatic characteristics of the characteristic metabolites, seeds from the HCQ region and HZC region have a strong herbal, woody, celery, and turpentine aroma. The concentration of secondary metabolites was highest in the seeds from the HCQ region followed by the HZC region, and it was the lowest in the JJC region. Altogether, this study investigates how geographical origins influence the metabolomic profile of celery seeds. The results can be used to guide the planting and harvesting of celery seeds in suitable regions.

Improvement of starvation resistance via periodic fasting is genetically variable in Drosophila melanogaster

AbstractOrganisms subjected to periodic nutrient limitation early in life exhibit improvements in aspects of survival, including resistance to some environmental stressors. Recent findings indicate that forms of periodic fasting, such as intermittent fasting and time‐restricted feeding, can improve starvation resistance. However, it remains unclear to what extent this survival improvement persists across different genetic backgrounds. In this study, we examine fasting‐induced starvation resistance across a broad survey of wild‐derived lineages and document genetic variation within this trait. We adopt a standard dietary intervention and show improvement in starvation resistance within a common laboratory lineage, replicating previous results. Next, we examine fasting‐induced starvation resistance across isofemale lines collected across latitudes and in different seasons, and among inbred lines derived from flies collected on different continents. We discover genetic variation of fasting‐induced starvation resistance and show that fasting improved starvation resistance as often as it worsened starvation resistance. Fasted flies generally showed reduced fat concentration, and their starvation survival varied with sex, season of collection and geographic origin. While specific lineages common to the laboratory can show a specific fasting‐induced phenotype, we show that this result is not consistent across genetic backgrounds, reinforcing the idea that phenotypes observed in historic laboratory strains may not be conserved across a species.

Matrix overcompensation calibration: A new strategy to correct matrix effects of carbon origin in multielement analysis by inductively coupled plasma mass spectrometry

BackgroundElemental analysis by inductively coupled plasma mass spectrometry (ICP-MS) may suffer from matrix effects; those caused by organic matrices cannot be corrected by internal standardization. A new strategy, matrix overcompensation calibration (MOC), was developed to correct such matrix effects. ResultsClear fruit juices were diluted 1:50 in 1 % HNO3 (v/v)- 0.5 % HCl (v/v)- 5 % ethanol (v/v). A standard series was treated likewise to construct an external calibration curve. As, Se, Cd, and Pb in juices were determined by dilute-and-shoot ICP-MS based on this MOC strategy. The results agreed with those obtained by standard addition calibration and microwave-aided digestion; data accuracy was validated by spike-recovery studies. SignificanceUnlike standard addition calibration, a single external calibration curve established by MOC can be applicable to juices of diversified fruit, geographical, and manufacturer origins enhancing productivity.

Elemental composition and contaminants of saffron from different origins and geographical discrimination using chemometrics

Elements such as As, Cd, Cr and Pb are classified as contaminants of major concern for public health, due to their high degree of toxicity. Saffron is an important medicinal herbal spice used in variety of food items, pharmaceutical medicines, and cosmetics. Presence of heavy metals in saffron will increase the health risk to consumers. Also, authentication of geographical origin of saffron is an issue of utmost importance for global trading. The present study is focused on investigation of elemental contaminants in saffron and elemental composition of saffron from India (Jammu and Kashmir); Iran and Afghanistan are also explored for geographical discrimination, using Chemometrics. In total, 29 elements including Ag, Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Si, Sr, Ti, Tl, V and Zn were analyzed using ICP-OES. Toxic elemental contaminants including As, Cd, Pb were found below the maximum permissible limit. Using PCA, elements B, Ni, Ba, Fe, V, Si, Al, Ti, K, Na, Sr, and Zn were found as significant discriminators of geographical origin. Elemental composition of saffron may be utilized, to prevent cases of falsified geographical origin in trade.

Correlation between climatic environment and characteristic components of 14 kinds of huajiao by thermal analysis techniques, GC‐MS and HS‐IMS

AbstractHuajiao (Zanthoxylum bungeanum Maxim.) is extensively cultivated in various countries, including China, Korea, and India, owing to its adaptability to diverse environments. This study comprehensively analyzed the volatile substance composition of 14 varieties of red huajiao with distinct geographical origins. Thermal analysis methods, gas chromatography‐mass spectrometry (GC‐MS), and headspace‐ion mobility chromatography (HS‐IMS) were employed to evaluate the total volatile substance composition and content. The study revealed minor variations in water content, volatile matter content, and fractions among the geographically sourced huajiao samples. Utilizing correlation analysis based on GC‐MS and orthogonal partial least squares discriminant analysis (OPLS‐DA) with HS‐IMS, a robust classification method for the 14 types of huajiao was developed. Applying the variable importance in the projection (VIP) method, seven distinctive components were identified as potential markers for distinguishing the geographical origins of red huajiao. By integrating climatic and topographical factors of the 14 huajiao varieties, the correlation analysis of GC‐MS, and OPLS‐DA classification outcomes from HS‐IMS elucidated the influence of geo‐environmental factors on huajiao components and contents. This research provides insights into the impact of diverse geographic environments on the constituents and characteristics of huajiao. It offers valuable guidance for selecting optimal cultivation locations to enhance huajiao quality, aiding consumers in making informed choices.

Genetic Diversity and Genome-Wide Association in Cowpeas (Vigna unguiculata L. Walp)

Cowpea is one of the most popular dry-land legumes cultivated for food and forage in arid and semi-arid areas. Genetic diversity for global germplasm can be organized into core collections providing optimum resources to serve breeding requirements. Here, we present diversity analysis and genome-wide association study (GWAS) results for part of the cowpea core collection of the United States Department of Agriculture (USDA) along with breeding line controls. Included in the analysis were a total of 373 accessions analyzed with 6880 Single Nucleotide Polymorphism (SNP) markers from Genotyping by Sequencing (GBS). Population structure differentiated accessions into two groups irrespective of geographical origin and formed three clusters based on taxa upon phylogenetic analysis. A total of 56 SNPs were significantly associated to nine traits including pod length (25 Quantitative Trait Nucleotides, QTNs), seed anti-oxidant content (7 QTNs), dry pod color (7 QTNs), plant maturity (5 QTNs), flower color (5 QTNs), seed weight (4 QTNs), tolerance to low phosphate (1 QTN), growth habit (1 QTN), and response to rock phosphate (1 QTN) using Bayesian-information, Linkage-disequilibrium Iteratively Nested Keyway (BLINK), and Fixed and random model Circulating Probability Unification (FarmCPU) association models. Key genes related to all significant SNPs were identified based on annotations of the cowpea reference genome, including a flavonoid gene controlling flower color (Vigun08g040200.1), a root nodulation regulator for tolerance to low phosphate (Vigun11g168000.1), and numerous genes involved in signaling, biosynthesis, metabolite transport, and abiotic stress. Our results highlight the importance of maintaining public phenotyping databases at USDA and strengthening collaborations for data collection in cowpea to maximize research impacts.

EXPRESS: Analyzing Brand Strategy on an International Scale: the Sponsorship Performance Cycle in Formula One Racing

Firms from a variety of industries regularly partner with Formula One (F1) racing teams to achieve marketing objectives on an international scale. The sponsored properties offer signals of brand foreignness/localness, country of origin, and the potential for highly visible achievements. Firms enter and exit brand partnerships with some of the world’s most famous athletes and iconic teams, yet the partnership decision-making process remains opaque, particularly concerning the impact of geographic origin and team performance among other criteria, including macroeconomic conditions and brand-related factors. This study contributes a quantitative model that analyzes 53 years of data encompassing more than 3,000 sponsorships across six continents. The findings improve understanding of brand partnership continuity/dissolution by explicating a shared nationality effect and a link with sponsored organizational performance that is robust across three distinct eras of F1. In doing so, the paper contributes to theory by completing the sponsorship performance cycle and distilling partnership limits to brand foreignness. The theory and quantitative analyses are buttressed by interviews with brand decision-makers, excerpts from which also shape the discussion of managerial applications. Implications include efficiencies in partner prospecting that enhance the likelihood of enduring brand relationships in sponsorship-linked international marketing.

The level of evidence in prosthodontics in relation to author’s characteristics: an analysis of three leading prosthodontics journals

PurposeThe purpose of this study was to examine the level of evidence (LOE) characteristics and associated factors that change over time in three leading prosthodontics journals. Materials and methodsArticles published in The Journal of Prosthetic Dentistry (JPD), International Journal of Prosthodontics (IJP), and Journal of Prosthodontics (JP) in 2013 and 2020 were reviewed by eight independent reviewers. After applying exclusion and inclusion criteria, the number of authors, the corresponding author's educational degree, corresponding author's origin in each clinical research article were recorded. The included articles were rated by reviewers according to the level of evidence criteria and proposed level of evidence-associated factors. Descriptive statistics, univariable, and binary logistic regression analysis were performed to investigate dependent variables and potentially associated factors. All independent variables with a significant effect were analyzed by using a multivariable test. The entry and exit alpha level were set at αE =0.15. The statistical significance was set at α=0.05. ResultsA total of 439 articles from 3 selected journals for the years studied met the inclusion criteria. The percentages of level 1, 2, 3, 4, and 5 articles were 2.7%, 11.4%, 9.6%, 13.4% and 62.9%, respectively. Univariable analysis results demonstrated significant associations related to the number of authors (P=.005), the corresponding author's educational degree (P=.022), and the corresponding author's geographic origin (P=.042). Multivariable analysis results demonstrated significant associations related to the number of authors (P=.002), and the corresponding author's geographic origin (P=.014). ConclusionsThe number of authors, CA degree, and CA origin had a significant association with the LOE of included prosthodontic studies. Although there was an increase in the number of publications from 2013 to 2020, the level of evidence trend shows no improvement over the years.

Global transmission of extended-spectrum cephalosporin resistance in Escherichia coli driven by epidemic plasmids

Extended-spectrum cephalosporins (ESCs) are third and fourth generation cephalosporin antimicrobials used in humans and animals to treat infections due to multidrug-resistant (MDR) bacteria. Resistance to ESCs (ESC-R) in Enterobacterales is predominantly due to the production of extended-spectrum β-lactamases (ESBLs) and plasmid-mediated AmpC β-lactamases (AmpCs). The dynamics of ESBLs and AmpCs are changing across countries and host species, the result of global transmission of ESC-R genes. Plasmids are known to play a key role in this dissemination, but the relative importance of different types of plasmids is not fully understood. In this study, Escherichia coli with the major ESC-R genes blaCTX-M-1, blaCTX-M-15, blaCTX-M-14 (ESBLs) and blaCMY-2 (AmpC), were selected from diverse host species and other sources across Canada, France and Germany, collected between 2003 and 2017. To examine in detail the vehicles of transmission of the ESC-R genes, long- and short-read sequences were generated to obtain complete contiguous chromosome and plasmid sequences (n=192 ESC-R E.coli). The types, gene composition and genetic relatedness of these plasmids were investigated, along with association with isolate year, source and geographical origin, and put in context with publicly available plasmid sequences. We identified five epidemic resistance plasmid subtypes with distinct genetic properties that are associated with the global dissemination of ESC-R genes across multiple E.coli lineages and host species. The IncI1 pST3 blaCTX-M-1 plasmid subtype was found in more diverse sources than the other main plasmid subtypes, whereas IncI1 pST12 blaCMY-2 was more frequent in Canadian and German human and chicken isolates. Clonal expansion also contributed to the dissemination of the IncI1 pST12 blaCMY-2 plasmid in ST131 and ST117 E.coli harbouring this plasmid. The IncI1 pST2 blaCMY-2 subtype was predominant in isolates from humans in France, while the IncF F31:A4:B1 blaCTX-M-15 and F2:A-:B- blaCTX-M-14 plasmid subtypes were frequent in human and cattle isolates across multiple countries. Beyond their epidemic nature with respect to ESC-R genes, in our collection almost all IncI1 pST3 blaCTX-M-1 and IncF F31:A4:B1 blaCTX-M-15 epidemic plasmids also carried multiple antimicrobial resistance (AMR) genes conferring resistance to other antimicrobial classes. Finally, we found genetic signatures in the regions surrounding specific ESC-R genes, identifying the predominant mechanisms of ESC-R gene movement, and using publicly available databases, we identified these epidemic plasmids from widespread bacterial species, host species, countries and continents. We provide evidence that epidemic resistance plasmid subtypes contribute to the global dissemination of ESC-R genes, and in addition, some of these epidemic plasmids confer resistance to multiple other antimicrobial classes. The success of these plasmids suggests that they may have a fitness advantage over other plasmid types and subtypes. Identification and understanding of the vehicles of AMR transmission are crucial to develop and target strategies and interventions to reduce the spread of AMR. This project was supported by the Joint Programming Initiative on Antimicrobial Resistance (JPIAMR), through the Medical Research Council (MRC, MR/R000948/1), the Canadian Institutes of Health Research (CFC-150770), and the Genomics Research and Development Initiative (Government of Canada), the German Federal Ministry of Education and Research (BMBF) grant no. 01KI1709, the French Agency for food environmental and occupational health & safety (Anses), and the French National Reference Center (CNR) for antimicrobial resistance. Support was also provided by the Biotechnology and Biological Sciences Research Council (BBSRC) through the BBSRC Institute Strategic Programme Microbes in the Food ChainBB/R012504/1 and its constituent project BBS/E/F/000PR10348 (Theme 1, Epidemiology and Evolution of Pathogens in the Food Chain).