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The evolution of herbicide resistance in weeds has emerged as one of the most serious threats to sustainable food production systems, which necessitates the evaluation of herbicides to determine their efficacy. The first herbicide resistance case in the Iberian Peninsula was reported about 50 years ago, wherein Panicum dichotomiflorum was found to be resistant (R) to atrazine in Spanish maize fields. Since then, herbicide resistance has evolved in 33 weed species, representing a total of 77 single-herbicide-resistance cases in this geographic area: 66 in Spain and 11 in Portugal. Changes in agricultural practices, namely the adoption of non-tillage systems and the increased use of herbicides, led to the selection of weed biotypes resistant to a wide range of herbicides. Nowadays the most important crops in Spain and Portugal (maize, winter cereals, rice, citrus, fruits, and olive orchards) are affected, with biotypes resistant to several mechanisms of action (MoAs), namely: ALS inhibitors (20 species), ACCase inhibitors (8 species), PS II inhibitors (18 species), and synthetic auxin herbicides (3 species). More recently, the fast increase in cases of resistance to the EPSPS-inhibiting herbicide glyphosate has been remarkable, with 11 species already having evolved resistance in the last 10 years in the Iberian Peninsula. The diversity of resistance mechanisms, both target-site and non-target-site, are responsible for the resistance to different MoAs, involving point mutations in the target site and enhanced rates of herbicide detoxification, respectively. More serious are the 13 cases reported with multiple-herbicide resistance, with three cases of resistance to three–four MoAs, and one case of resistance to five MoAs. Future research perspectives should further study the relationship between management strategies and the occurrence of TSR and NTSR resistance, to improve their design, develop monitoring and diagnostic tools for herbicide resistance, and deepen the study of NTSR resistance. [ABSTRACT FROM AUTHOR]

Multiple resistance mechanisms to ALS inhibitors and auxin mimics in two Papaver rhoeas populations were investigated in wheat fields from Portugal. Dose-response trials, also with malathion (a cytochrome P450 inhibitor), cross-resistance patterns for ALS inhibitors and auxin mimics, alternative herbicides tests, 2,4-D and tribenuron-methyl absorption, translocation and metabolism experiments, together with ALS activity, gene sequencing and enzyme modelling and ligand docking were carried out. Results revealed two different resistant profiles: one population (R1) multiple resistant to tribenuron-methyl and 2,4-D, the second (R2) only resistant to 2,4-D. In R1, several target-site mutations in Pro197 and enhanced metabolism (cytochrome P450-mediated) were responsible of tribenuron-methyl resistance. For 2,4-D, reduced transport was observed in both populations, while cytochrome P450-mediated metabolism was also present in R1 population. Moreover, this is the first P. rhoeas population with enhanced tribenuron-methyl metabolism. This study reports the first case for P. rhoeas of the amino acid substitution Pro197Phe due to a double nucleotide change. This double mutation could cause reduced enzyme sensitivity to most ALS inhibitors according to protein modelling and ligand docking. In addition, this study reports a P. rhoeas population resistant to 2,4-D, apparently, with reduced transport as the sole resistance mechanism. [Display omitted] • Tribenuron P450-mediated metabolism is first reported in Papaver rhoeas. • The double mutation Pro197Phe is found for the first time in P. rhoeas , second world case. • Ligand docking predicts cross resistance to ALS inhibitors for the Pro197Phe. • Impaired transport alone could confer cross-resistance to all auxin mimics. • Various resistance mechanisms evolve in P. rhoeas to ALS inhibitors and auxin mimics. [ABSTRACT FROM AUTHOR]

A contemporary serious lack of scientific knowledge by the general public and many decision-makers is now quite perceptible, both globally and in Portugal. Living in a science-driven technological world filled with scientific illiteracy is dangerous and a path toward disaster. Recent years brought a fairly strong global movement promoting the so-called "alternative therapy" that also affected Portugal. I propose an evidence-based ethics reflection and argumentation, both encompassing the global and the specific Portuguese reality. I debate the specific arguments used in favour of alternative therapies, demonstrating the inherent fallacies of thought, deliberate manipulation of words and concepts, and the dire consequences for global and local health politics by following this line of biased reasoning., (© 2022. The Author(s).)

Purpose: Septic arthritis can be disabling and life-threatening, requiring prompt diagnosis and treatment. The infectious agent is not always identified in these patients. We revaluate septic arthritis cases discharged from our department, describing the affected population, causative microorganisms and antibiotic therapy used, and characterised differences between patients with and without isolated pathogenic agents., Methods: Sixty-eight septic arthritis patients were included in this study. Diagnosis was based on clinical findings, and/or the presence of joint purulent material, and/or bacterial pathogen isolation from joint fluid/synovial membrane/blood cultures and response to antibiotics. Data analysis was performed using SPSS 20., Results: Patients had a mean age of 61.1 ± 18.8 years, without sex predominance. 26.5 % had an infection ≤ 15 days before septic arthritis diagnosis. Besides previous infection, 57.4 % had ≥ 1 risk factors for septic arthritis, most commonly pharmacological immunosuppression (20.6 %), diabetes mellitus type 2 (19.1 %) and rheumatoid arthritis (17.6 %). The knee was the most often affected (54.3 %). Only 39.7 % presented fever from clinical onset until hospital admission (mean 13.4 ± 18.9 days). Leucocytosis was present in 45.6 % of patients, elevated erythrocyte sedimentation rate (ESR) in 75 % and elevated C-reactive protein (CRP) in 97.1 %. 5.9 % had articular damage attributable to septic arthritis. An infectious agent was isolated in 41.2 % of patients, with Staphylococcus aureus being the most frequent. 38.7 % of synovial fluid and 23.5 % of synovial membrane cultures were positive. Patients with an identified infectious agent have no significant differences other than more days of hospitalisation (p = 0.003) and in-hospital antibiotic treatment (p = 0.017)., Conclusion: Synovial fluid and synovial membrane cultures more often identified pathogens compared to blood or urine cultures. Patients with and without an identified infectious agent have similar demographic, clinical, laboratory and radiographic characteristics.

Objective: This study examined demographic and clinical characteristics of frequent users of a psychiatric inpatient unit in Portugal., Methods: Data (2004-2008) for 1,348 consecutive psychiatric inpatients were reviewed. Frequent users (N=137), who had at least three admissions in the study period, were compared with nonfrequent users (N=1,211) on age, gender, race-ethnicity, diagnosis, and compulsory admissions. Data were analyzed with chi square and Student's t tests., Results: Frequent users accounted for 29% of admissions. They were significantly younger than nonfrequent users (39±14 versus 44±17, p<.001), and a larger proportion had compulsory admissions (28% versus 14%, p<.001). The frequent user group also had significantly higher rates of bipolar disorder (61% versus 46%, p<.001) and schizophrenia (29% versus 18%, p<.003)., Conclusions: Understanding characteristics of frequent users can inform development of appropriate services. Research should address other variables related to frequent admissions, including socioeconomic factors, general medical and psychiatric comorbidities, and treatment compliance.