Cell-cell communication between malaria-infected red blood cells via exosome-like vesicles.

Cell-cell communication is an important mechanism for information exchange promoting cell survival for the control of features such as population density and differentiation. We determined that Plasmodium falciparum-infected red blood cells directly communicate between parasites within a population using exosome-like vesicles that are capable of delivering genes. Importantly, communication via exosome-like vesicles promotes differentiation to sexual forms at a rate that suggests that signaling is involved. Furthermore, we have identified a P. falciparum protein, PfPTP2, that plays a key role in efficient communication. This study reveals a previously unidentified pathway of P. falciparum biology critical for survival in the host and transmission to mosquitoes. This identifies a pathway for the development of agents to block parasite transmission from the human host to the mosquito.

A Self-Reported Study on Explanatory Variables of Stress in Multiple Sclerosis Patients: Exploring the Effect of Physical Conditions and Emotion Regulation Processes.

BACKGROUND: Multiple sclerosis (MS)-linked stress is frequent, multidetermined and facilitates the onset/exacerbation of MS. However, few explanatory models of stress analysed the joint explanatory effect of emotion regulation and clinical outcomes of MS in those patients. OBJECTIVE: This study explored whether self-reported MS-related conditions (number of relapses, fatigue and global disability) and specific emotion regulation processes (experiential avoidance and self-compassion) explain stress symptoms in MS patients. METHODS: The MS sample comprised 101 patients with MS diagnosis receiving treatment in hospitals and recruited through the Portuguese MS Society. The no-MS sample included 134 age-, sex- and years of education-matched adults without MS recruited from the general Portuguese population. Both samples did not report other neurological disorders. Data were collected using self-response measures. RESULTS: All potential explanatory variables differed significantly between samples, with higher scores found in MS patients. In MS clinical sample, those variables and years of education correlated with stress symptoms and predicted stress symptoms in simple linear regression models. These results allowed their selection as covariates in a multiple linear regression model. Years of education, the number of relapses, fatigue and experiential avoidance significantly predicted 51% of stress symptoms' total variance. CONCLUSIONS: This study provides preliminary evidence on the importance of clinicians and researchers considering the simultaneous contribution of years of education, the number of perceived relapses, fatigue and experiential avoidance as factors that can increase vulnerability to stress in MS patients. Psychological intervention programmes that tackle these factors and associated stress symptomatology should be implemented.

White spot lesions: diagnosis and treatment - a systematic review.

BACKGROUND: White spot lesions represent the first stage of caries and their prevalence has been increasing in recent years, particularly in patients undergoing orthodontic treatment. DIferential diagnosis and lesion activity are essential to decide on the clinical approaches to treatment. The aim of this study is to understand if the new diagnostic tools such as fluorescence, microradiography and computed microtomography have the potential to change the conventional treatment of white spots". METHODS: A systematic search of available studies in the literature was carried out, using PRISMA guidelines, in Pubmed and Scopus electronic databases and manually to identify relevant articles to answer the PICO question: "Do the new diagnostic tools have the potential to change the conventional treatment of white spots?". This systematic review included randomized controlled trials (RCT), cross-sectional and longitudinal studies complying with the following inclusion criteria: (i) studies in humans, (ii) studies about white spot lesions, (iii) studies published between 2012 and 2023, (iv) studies having both diagnosis and treatment and (v) studies with full text available. In this review we excluded other systematic reviews of clinical trials and in vitro studies. The RoB tool was used to assess the risk of bias. RESULTS: The systematic literature search identified 143 potentially relevant references, which after applying the exclusion criteria, resulted in 20 articles. Regarding diagnostic methods, most articles found were based on conventional methods of visual examination (n:10) or fluorescence (n:7). The least referenced diagnostic techniques were based on the use of clinical photographs (n:2), cross-sectional microradiography (n:1) and computed microtomography (n:1). The use of DIAGNOdent was reported by 3 in vitro studies. With regard to therapies, most studies reported the use of infiltrating resin (n:7) and fluoride-based products (n:5). Other studies have reported the use of self-assembling peptide P11-4 (n:1), home care (n:1), casein phosphopeptide-amorphous calcium phosphate (n:2) and hydrochloric acid (n:1). Combination therapies were also considered. CONCLUSION: Diagnostic tool does not have the potential to change the form of treatment, whether it is a conventional method or a more differentiated one.

Pseudomonadota in the oral cavity: a glimpse into the environment-human nexus.

The phylum Pseudomonadota is amongst the most represented in the environment, with a comparatively lower prevalence in the human oral cavity. The ubiquity of Pseudomonadota and the fact that the oral cavity is the most likely entry portal of bacteria from external sources underlie the need to better understand its occurrence in the interface environment-humans. Yet, the relevance oral Pseudomonadota is largely underexplored in the scientific literature, a gap that this review aims at addressing by making, for the first time, an overview of the diversity and ecology of Pseudomonadota in the oral cavity. The screening of scientific literature and human microbiome databases unveiled 1328 reports of Pseudomonadota in the oral cavity. Most of these belonged to the classes Beta- and Gammaproteobacteria, mainly to the families Neisseriaceae, Campylobacteriaceae, and Pasteurelaceae. Others also regularly reported include genera such as Enterobacter, Klebsiella, Acinetobacter, Escherichia, Burkholderia, or Citrobacter, whose members have high potential to acquire virulence and antibiotic resistance genes. This review provides evidence that clinically relevant environmental Pseudomonadota may colonize humans via oral cavity. The need for further investigation about Pseudomonadota at the environment-oral cavity interface and their role as vectors potentially involved in virulence and antibiotic resistance transmission is demonstrated. KEY POINTS: • Neisseriaceae, Campylobacteriaceae, and Pasteurelaceae are part of the core oral microbiome • Enterobacteriaceae, Acinetobacter, or Burkholderia are frequent in the oral microbiome • Gut dysbiosis may be associated with colonization by ubiquitous oral Pseudomonadota.

Evidence of Australian wild deer exposure to N. caninum infection and potential implications for the maintenance of N. caninum sylvatic cycle.

Infections with the coccidian parasite Neospora caninum affect domestic and wild animals worldwide. In Australia, N. caninum infections cause considerable losses to the cattle industry with seroprevalence of 8.7% in beef and 10.9% in dairy cattle. Conversely, the role of wild animals, in maintaining the parasite cycle is also unclear. It is possible that native or introduced herbivorous species could be reservoir hosts of N. caninum in Australia, but to date, this has not been investigated. We report here the first large-scale screening of N. caninum antibodies in Australian wild deer, spanning three species (fallow, red and sambar deer). Consequently, we also assessed two commercial cELISA tests validated for detecting N. caninum in cattle for their ability to detect N. caninum antibodies in serum samples of wild deer. N. caninum antibodies were detected in 3.7% (7/189, 95% CI 1.8 - 7.45) of the wild deer serum samples collected in south-eastern Australia (n = 189), including 97 fallow deer (Dama dama), 14 red deer (Cervus elaphus), and 78 sambar deer (Rusa unicolor). Overall, our study provides the first detection of N. caninum antibodies in wild deer and quantifies deer's potential role in the sylvatic cycle of N. caninum.

Altered gastrointestinal tract structure and microbiome following cerebral malaria infection.

Cerebral malaria (CM) is the most severe form of malaria with the highest mortality rate and can result in life-long neurological deficits and ongoing comorbidities. Factors contributing to severity of infection and development of CM are not fully elucidated. Recent studies have indicated a key role of the gut microbiome in a range of health conditions that affect the brain, but limited microbiome research has been conducted in the context of malaria. To address this knowledge gap, the impact of CM on the gut microbiome was investigated in mice. C57BL/6J mice were infected with Plasmodium berghei ANKA (PbA) parasites and compared to non-infected controls. Microbial DNA from faecal pellets collected daily for 6-days post-infection were extracted, and microbiome comparisons conducted using 16S rRNA profiling. We identified significant differences in the composition of bacterial communities between the infected and the non-infected groups, including a higher abundance of the genera Akkermansia, Alistipes and Alloprevotella in PbA-infected mice. Furthermore, intestinal samples were collected post-cull for morphological analysis. We determined that the caecal weight was significantly lower, and the small intestine was significantly longer in PbA-infected mice than in the non-infected controls. We concluded that changes in microbial community composition were primarily driven by the infection protocol and, to a lesser extent, by the time of infection. Our findings pave the way for a new area of research and novel intervention strategies to modulate the severity of cerebral malaria disease.

Neuropathic pain, cognitive fusion, and alexithymia in patients with multiple sclerosis: Cross-sectional evidence for an explanatory model of anxiety symptoms.

Multiple sclerosis (MS) presents a high prevalence, a marked increase worldwide, and a relevant impact on patients, public health, and society. Anxiety often cooccurs with MS and can contribute to the worsening of MS symptoms. However, knowledge about predictors of anxiety in Patients with MS (PwMS) is scarce. OBJECTIVE: This preliminary study explored a novel model for anxiety symptoms in PwMS, including neuropathic pain (NeP), cognitive fusion (CF), experiential avoidance (EA), and alexithymia as explanatory factors. METHOD: This cross-sectional study integrated two independent convenience samples: 107 PwMS recruited from the Portuguese Society for Multiple Sclerosis and 97 age- and gender-matched participants without the MS diagnosis (no-MS sample) recruited from the Portuguese general population. Self-report questionnaires that measured the constructs included in the model were administered to both groups. RESULTS: PwMS showed significantly higher values regarding anxiety symptoms and their explanatory variables (NeP, CF, EA, alexithymia) in comparison to non-MS participants. In the MS sample, no correlations were found between anxiety symptoms and sociodemographic and clinical characteristics. NeP, CF, and alexithymia showed significant correlations with anxiety symptoms and significantly explained this symptomatology in simple linear regression models. Thus, these variables were retained in the multiple linear regression model and emerged as significant regressors that together explained 38% of the variance in anxious symptomatology in PwMS. CONCLUSIONS: This preliminary study provides novel evidence on NeP and some maladaptive emotion regulation strategies related to EA/psychological inflexibility, as vulnerability to anxiety in PwMS can be considerably increased by CF and alexithymia. Clinical implications were discussed.

Nocardia spp. isolation in chronic lung diseases: Are there differences between patients with pulmonary nocardiosis and Nocardia colonization?

AIMS: Chronic lung diseases are a recognized risk factor for Nocardia spp. INFECTION: Nocardia spp. isolation does not inevitably imply disease, and thus colonization must be considered. Here, we aimed to analyse the differences between pulmonary nocardiosis (PN) and Nocardia spp. colonization in patients with chronic lung diseases. METHODS AND RESULTS: A retrospective study of patients with laboratory confirmation of isolation of Nocardia spp. in at least one respiratory sample was performed. Patients with PN and Nocardia spp. colonization were compared. There were 71 patients with Nocardia spp. identification, 64.8% were male, with a mean age of 67.7 ± 11.2 years. All patients had ≥1 pre-existing chronic lung disease, and 19.7% of patients were immunocompromised. PN and Nocardia spp. colonization were considered in 26.8% and 73.2% of patients, respectively. Symptoms and chest CT findings were significantly more frequent in patients with PN (p < 0.001). During follow-up time, 12 (16.9%) patients died, 6 in PN group. Immunosuppression, constitutional symptoms, haematological malignancy and PN diagnosis were associated with significantly shorter survival times, despite only immunosuppression (HR 3.399; 95% CI 1.052-10.989) and PN diagnosis (HR 3.568; 95% CI 1.078-11.910) remained associated with a higher death risk in multivariate analysis. CONCLUSIONS: PN was associated with clinical worsening, more chest CT findings and worse clinical outcomes. SIGNIFICANCE AND IMPACT OF STUDY: Nocardia spp. isolation in chronic lung disease patients is more common than expected and the differentiation between colonization and disease is crucial.

Experiential avoidance, uncompassionate self-responding, and peritraumatic depersonalization/derealization: A novel mediation model for war-related PTSD symptomatology.

OBJECTIVE: To explore a novel model for war-related posttraumatic stress disorder (PTSD) symptomatology including emotion regulation processes, namely experiential avoidance (EA) and uncompassionate self-responding (USR), mediating the impact of childhood threat memories, combat exposure distress, combat and noncombat threats, and peritraumatic depersonalization/derealization (PDD) on PTSD symptomatology. METHOD: A sample of 650 male Portuguese Overseas War veterans filled self-report instruments. RESULTS: The model explained 59% of the variance of PTSD symptomatology. Both EA and USR mediated the effects of noncombat threats and PDD on PTSD. Additionally, EA mediated combat exposure distress and USR mediated childhood threat memories. Combat exposure distress, combat and noncombat threats, and PDD showed direct effects on PTSD symptomatology. CONCLUSION: The findings help to better understand the relationship between predictive factors of war-related PTSD in clinical and research settings, providing novel insights on the effects of combat exposure distress, and the different effects of combat and noncombat-related threats on PTSD.

Synthesis of Biologically Active Heterospirocycles through Iterative 1,3-Dipolar Cycloaddition Pathways.

We demonstrate the novel spiroannulation of exo-imines with 1,3-dipoles, for the first time, leading to 3D spirocycles with a secondary amine (NH) in the spiro-ring. The synthetic method described herein allows access to these previously unexplored heterospirocyclic cores that have application in the discovery of functional molecules for medicinal and materials science. This was demonstrated by discovering an unprecedented class of heterospirocycles with antimalarial activity against the human protozoan P. falciparum.

Prognostic factors for early relapse in non-metastatic triple negative breast cancer - real world data.

BACKGROUND: Triple negative breast cancer (TNBC) has the worst prognosis amongst all subtypes. Studies have shown that the achievement of pathologic complete response in the breast and axilla correlates with improved survival. The aim of this study was to identify clinical or pathological features of real-life TNBC patients with a higher risk of early relapse. MATERIALS AND METHODS: Single-centre retrospective analysis of 127 women with TNBC, stage II-III, submitted to neoadjuvant treatment and surgery between January 2016 and 2020. Multivariate Cox regression analysis for disease free survival (DFS) at 2 years was performed and statistically significant variables were computed into a prognostic model for early relapse. RESULTS: After 29 months of median follow-up, 105 patients (82.7%) were alive and, in total, 38 patients (29.9%) experienced recurrence. The 2-year DFS was 73% (95% CI: 21.3-22.7). In multivariate analysis, being submitted to neoadjuvant radiotherapy [HR 2.8 (95% CI: 1.2-6.4), p = 0.017] and not achieving pathologic complete response [HR 0.3 (95% CI: 0.1-1.7), p = 0.011] were associated with higher risk of recurrence. In our prognostic model, the presence of at least one of these variables defined a subgroup of patients with a worse 2-year DFS than those without these features (59% vs. 90%, p < 0.001, respectively). CONCLUSIONS: In this real-life non-metastatic TNBC cohort, neoadjuvant radiotherapy (performed due to insufficient clinical response to neoadjuvant chemotherapy or significant toxicity) impacted as an independent prognostic factor for relapse along with the absence of pathologic complete response identifying a subgroup of higher risk patients for early relapse that might merit a closer follow-up.

RNA Splicing Defects in Hypertrophic Cardiomyopathy: Implications for Diagnosis and Therapy.

Hypertrophic cardiomyopathy (HCM), the most common inherited heart disease, is predominantly caused by mutations in genes that encode sarcomere-associated proteins. Effective gene-based diagnosis is critical for the accurate clinical management of patients and their family members. However, the introduction of high-throughput DNA sequencing approaches for clinical diagnostics has vastly expanded the number of variants of uncertain significance, leading to many inconclusive results that limit the clinical utility of genetic testing. More recently, developments in RNA analysis have been improving diagnostic outcomes by identifying new variants that interfere with splicing. This review summarizes recent discoveries of RNA mis-splicing in HCM and provides an overview of research that aims to apply the concept of RNA therapeutics to HCM.

Portuguese version of the Posttraumatic Stress Disorder Checklist for DSM-5 (PCL-5): Comparison of latent models and other psychometric analyses.

OBJECTIVE: This psychometric study explores the Portuguese version of the Posttraumatic Stress Disorder (PTSD) Checklist (PCL-5). It aims to clarify the best-fitting latent structure among competing PTSD models (Diagnostic and Statistical Manual of Mental Disorders-fifth edition [DSM-5], Dysphoria, Dysphoric Arousal, Anhedonia, Externalizing Behavior, And Hybrid models) and its implications for PTSD measurement. METHOD: Psychometric analyses were conducted in a sample from the general population of firefighters (N = 446), except the temporal stability, which was tested in a subsample of 100 participants. RESULTS: The models presented significant differences in a global fit. The Hybrid model presented the best-fitting structure, but the DSM-5 model showed more favorable reliability and convergent validity in Confirmatory Factor Analyses. The DSM-5 model also proved to be internally consistency, temporally stable, and presented convergent validity. CONCLUSION: The Portuguese version of PCL-5 is reliable and valid. The findings suggest the appropriateness of the DSM-5 model to assess PTSD symptomatology, encouraging its use in clinical, and research settings.

Pharmacological inhibition of the spliceosome subunit SF3b triggers exon junction complex-independent nonsense-mediated decay.

Spliceostatin A, meayamycin, and pladienolide B are small molecules that target the SF3b subunit of the spliceosomal U2 small nuclear ribonucleoprotein (snRNP). These compounds are attracting much attention as tools to manipulate splicing and for use as potential anti-cancer drugs. We investigated the effects of these inhibitors on mRNA transport and stability in human cells. Upon splicing inhibition, unspliced pre-mRNAs accumulated in the nucleus, particularly within enlarged nuclear speckles. However, a small fraction of the pre-mRNA molecules were exported to the cytoplasm. We identified the export adaptor ALYREF as being associated with intron-containing transcripts and show its requirement for the nucleo-cytoplasmic transport of unspliced pre-mRNA. In contrast, the exon junction complex (EJC) core protein eIF4AIII failed to form a stable complex with intron-containing transcripts. Despite the absence of EJC, unspliced transcripts in the cytoplasm were degraded by nonsense-mediated decay (NMD), suggesting that unspliced transcripts are degraded by an EJC-independent NMD pathway. Collectively, our results indicate that although blocking the function of SF3b elicits a massive accumulation of unspliced pre-mRNAs in the nucleus, intron-containing transcripts can still bind the ALYREF export factor and be transported to the cytoplasm, where they trigger an alternative NMD pathway.

The conserved apicomplexan Aurora kinase TgArk3 is involved in endodyogeny, duplication rate and parasite virulence.

Aurora kinases are eukaryotic serine/threonine protein kinases that regulate key events associated with chromatin condensation, centrosome and spindle function and cytokinesis. Elucidating the roles of Aurora kinases in apicomplexan parasites is crucial to understand the cell cycle control during Plasmodium schizogony or Toxoplasma endodyogeny. Here, we report on the localization of two previously uncharacterized Toxoplasma Aurora-related kinases (Ark2 and Ark3) in tachyzoites and of the uncharacterized Ark3 orthologue in Plasmodium falciparum erythrocytic stages. In Toxoplasma gondii, we show that TgArk2 and TgArk3 concentrate at specific sub-cellular structures linked to parasite division: the mitotic spindle and intranuclear mitotic structures (TgArk2), and the outer core of the centrosome and the budding daughter cells cytoskeleton (TgArk3). By tagging the endogenous PfArk3 gene with the green fluorescent protein in live parasites, we show that PfArk3 protein expression peaks late in schizogony and localizes at the periphery of budding schizonts. Disruption of the TgArk2 gene reveals no essential function for tachyzoite propagation in vitro, which is surprising giving that the P. falciparum and P. berghei orthologues are essential for erythrocyte schizogony. In contrast, knock-down of TgArk3 protein results in pronounced defects in parasite division and a major growth deficiency. TgArk3-depleted parasites display several defects, such as reduced parasite growth rate, delayed egress and parasite duplication, defect in rosette formation, reduced parasite size and invasion efficiency and lack of virulence in mice. Our study provides new insights into cell cycle control in Toxoplasma and malaria parasites and highlights Aurora kinase 3 as potential drug target.

Characterization of a continuous agitated cell reactor for oxygen dependent biocatalysis.

Biocatalytic oxidation reactions employing molecular oxygen as the electron acceptor are difficult to conduct in a continuous flow reactor because of the requirement for high oxygen transfer rates. In this paper, the oxidation of glucose to glucono-1,5-lactone by glucose oxidase was used as a model reaction to study a novel continuous agitated cell reactor (ACR). The ACR consists of ten cells interconnected by small channels. An agitator is placed in each cell, which mixes the content of the cell when the reactor body is shaken by lateral movement. Based on tracer experiments, a hydrodynamic model for the ACR was developed. The model consisted of ten tanks-in-series with back-mixing occurring within and between each cell. The back-mixing was a necessary addition to the model in order to explain the observed phenomenon that the ACR behaved as two continuous stirred tank reactors (CSTRs) at low flow rates, while it at high flow rates behaved as the expected ten CSTRs in series. The performance of the ACR was evaluated by comparing the steady state conversion at varying residence times with the conversion observed in a stirred batch reactor of comparable size. It was found that the ACR could more than double the overall reaction rate, which was solely due to an increased oxygen transfer rate in the ACR caused by the intense mixing as a result of the spring agitators. The volumetric oxygen transfer coefficient, kL a, was estimated to be 344 h-1 in the 100 mL ACR, opposed to only 104 h-1 in a batch reactor of comparable working volume. Interestingly, the large deviation from plug flow behavior seen in the tracer experiments was found to have little influence on the conversion in the ACR, since both a plug flow reactor (PFR) model and the backflow cell model described the data sufficiently well. Biotechnol. Bioeng. 2017;114: 1222-1230. © 2017 Wiley Periodicals, Inc.

Role of plasmepsin V in export of diverse protein families from the Plasmodium falciparum exportome.

Plasmodium falciparum exports several hundred effector proteins that remodel the host erythrocyte and enable parasites to acquire nutrients, sequester in the circulation and evade immune responses. The majority of exported proteins contain the Plasmodium export element (PEXEL; RxLxE/Q/D) in their N-terminus, which is proteolytically cleaved in the parasite endoplasmic reticulum by Plasmepsin V, and is necessary for export. Several exported proteins lack a PEXEL or contain noncanonical motifs. Here, we assessed whether Plasmepsin V could process the N-termini of diverse protein families in P. falciparum. We show that Plasmepsin V cleaves N-terminal sequences from RIFIN, STEVOR and RESA multigene families, the latter of which contain a relaxed PEXEL (RxLxxE). However, Plasmepsin V does not cleave the N-terminal sequence of the major exported virulence factor erythrocyte membrane protein 1 (PfEMP1) or the PEXEL-negative exported proteins SBP-1 or REX-2. We probed the substrate specificity of Plasmepsin V and determined that lysine at the PEXEL P3 position, which is present in PfEMP1 and other putatively exported proteins, blocks Plasmepsin V activity. Furthermore, isoleucine at position P1 also blocked Plasmepsin V activity. The specificity of Plasmepsin V is therefore exquisitely confined and we have used this novel information to redefine the predicted P. falciparum PEXEL exportome.

Imaging dynamic interactions between spliceosomal proteins and pre-mRNA in living cells.

The ability to observe protein dynamics in living cells is critical for the mechanistic understanding of highly flexible biological processes such as pre-mRNA splicing by the spliceosome. Splicing relies on intricate RNA and protein networks that are repeatedly rearranged during spliceosome assembly. Here we describe a method based on fluorescence microscopy that has been used by our and other laboratories to study interaction of spliceosomal proteins with nascent pre-mRNA in living cells. The method involves co-expressing in mammalian cells the target pre-mRNA labeled with one color, and the spliceosomal protein tagged with another color. The diffusion coefficient of the protein as well as its association and dissociation rates with the pre-mRNA are estimated by fluorescence recovery after photobleaching (FRAP) or photoactivation.

Nima- and Aurora-related kinases of malaria parasites.

Completion of the life cycle of malaria parasite requires a succession of developmental stages which vary greatly with respect to proliferation status, implying a tightly regulated control of the parasite's cell cycle, which remains to be understood at the molecular level. Progression of the eukaryotic cell cycle is controlled by members of mitotic kinase of the families CDK (cyclin-dependent kinases), Aurora, Polo and NIMA. Plasmodium parasites possess cyclin-dependent protein kinases and cyclins, which strongly suggests that some of the principles underlying cell cycle control in higher eukaryotes also operate in this organism. However, atypical features of Plasmodium cell cycle organization and important divergences in the composition of the cell cycle machinery suggest the existence of regulatory mechanisms that are at variance with those of higher eukaryotes. This review focuses on several recently described Plasmodium protein kinases related to the NIMA and Aurora kinase families and discusses their functional involvement in parasite's biology. Given their demonstrated essential roles in the erythrocytic asexual cycle and/or sexual stages, these enzymes represent novel potential drug targets for antimalarial intervention aiming at inhibiting parasite replication and/or blocking transmission of the disease. This article is part of a Special Issue entitled: Inhibitors of Protein Kinases (2012).

Assessing Antimicrobial Efficacy on Plastics and Other Non-Porous Surfaces: A Closer Look at Studies Using the ISO 22196:2011 Standard.

The survival and spread of foodborne and nosocomial-associated bacteria through high-touch surfaces or contamination-prone sites, in either healthcare, domestic or food industry settings, are not always prevented by the employment of sanitary hygiene protocols. Antimicrobial surface coatings have emerged as a solution to eradicate pathogenic bacteria and prevent future infections and even outbreaks. Standardised antimicrobial testing methods play a crucial role in validating the effectiveness of these materials and enabling their application in real-life settings, providing reliable results that allow for comparison between antimicrobial surfaces while assuring end-use product safety. This review provides an insight into the studies using ISO 22196, which is considered the gold standard for antimicrobial surface coatings and examines the current state of the art in antimicrobial testing methods. It primarily focuses on identifying pitfalls and how even small variations in methods can lead to different results, affecting the assessment of the antimicrobial activity of a particular product.