RESUMEN
Global biodiversity is under substantial threat due to biological invasions, a problem exacerbated by climate change. Such invasions have detrimental effects on the environment, economy, and human health, resulting in significant financial burdens. Recently, understanding these challenges has become a highlighted priority within the scientific community. This study focuses on the evaluation of Schinus terebinthifolia, native to South America, and its invasive spread into North and Central America, which has resulted in wide distribution and considerable impact. The primary objectives of this study include analyzing the potential distribution of the species under current and future climate scenarios, identifying the areas where its climatic niche is changing. Data collection encompassed a vast dataset of over 30,000 occurrence records of this species, from the following databases: (1) The Global Biodiversity Information Facility provided 22,163 records (GBIF), (2) The virtual Herbarium Reflora contributed 1,438 records, and NeoTropTree made available 6,591 records. Following a rigorous filtering process, 992 occurrences were considered for modeling. In this process, we utilized climate data and climate projections, employing various algorithms, with an emphasis on the consensus model methodology. The research results reveal a clear trend of reduced habitat suitability for S. terebinthifolia, especially under scenarios of high global warming. This accentuates the urgency of implementing emission control measures and mitigation strategies. Additionally, the study underscores the crucial importance of continuous monitoring, as well as actions for controlling and restoring affected ecosystems. The significant role played by S. terebinthifolia in both its native and invaded areas highlights the need for comprehensive management approaches. In the face of climate change and biodiversity threats, this study provides insightful observations on the dynamics of biological invasions. Success in addressing these issues relies on close cooperation between the scientific community, policymakers, land managers, and local communities. This collaboration is essential for guiding and conducting conservation and biodiversity management efforts in an ever-evolving world.
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Anacardiaceae , Biodiversidad , Cambio Climático , Especies Introducidas , Brasil , Ecosistema , Modelos Biológicos , SchinusRESUMEN
The increasing global importance of pink peppertree (Schinus terebinthifolia, Anacardiaceae) as a high-value commercial crop and its potential for expansion in production demand appropriate management due to uncertainties regarding its sexual system. This study focused on evaluating the morphology of sterile and fertile floral whorls, as well as analyzing the sexual system of pink pepper in two populations in northeastern Brazil. The results revealed no significant differences in the morphological characteristics of the flowers between the studied areas, suggesting that the species possesses notable adaptability to environmental conditions. However, a significant difference in the proportion of staminate individuals was observed in both areas, representing over 88% and 72%, respectively. A correlation was observed between the size of the stamens and the presence of apparently atrophied pistils (r=0.275; df=178; p<0.001), along with the occurrence of fruits in these hermaphroditic plants. In this context, the species should be considered gynodioecious due to the presence of plants with hermaphroditic flowers and plants with pistillate flowers. However, further research is essential to elucidate the role of pollinators, especially bees and wasps, and to better understand the fruiting process in hermaphroditic flowers. These insights have the potential to significantly enhance management aiming for efficient fruit production, promoting its economic and ecological relevance.
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Anacardiaceae , Flores , Flores/anatomía & histología , Anacardiaceae/anatomía & histología , Anacardiaceae/clasificación , Brasil , Reproducción/fisiología , Polinización , SchinusRESUMEN
BACKGROUND: Dupilumab, a fully human monoclonal antibody targeting the alpha subunit of IL-4 was recently approved for the treatment of moderate-to-severe atopic dermatitis (AD) in adult patients. OBJECTIVE: To assess dupilumab effectiveness and safety in adults with moderate-to-severe AD in a real-life Italian multicentre retrospective cohort. METHODS: Adult moderate-to-severe AD patients, referring to 39 Italian centers, received dupilumab in the context of a national patient access program. Disease assessment was performed at baseline, after 4 and 16 weeks of treatment using Eczema-Area-and-Severity-Index (EASI) score, itch and sleep numerical-rating-score (itch-NRS, sleep-NRS) and Dermatology-Life-Quality-Index (DLQI). RESULTS: A total of 109 (71 M/38F) patients was studied. There was a significant reduction in EASI score, itch-NRS, sleep-NRS and DLQI from baseline to week 4 and a further significant decline to week 16. EASI 50, EASI75 and EASI90 were achieved by 59.6%, 28.4% and 9.3% of patients at 4 weeks and by 87.2%, 60.6% and 32.4% of them at 16 weeks, respectively. Adverse events were experienced by 19.2% (21/109) of the patients and they were all mild in intensity, being conjunctivitis the most common side effect. CONCLUSIONS: Dupilumab significantly improved disease severity, pruritus, sleep loss and quality of life with an acceptable safety profile.
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Anticuerpos Monoclonales Humanizados/administración & dosificación , Dermatitis Atópica/tratamiento farmacológico , Prurito , Calidad de Vida , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prurito/tratamiento farmacológico , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Sueño , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: A transition from a subtyping to a phenotyping approach in rosacea is underway, allowing individual patient management according to presenting features instead of categorization by predefined subtypes. The ROSacea COnsensus (ROSCO) 2017 recommendations further support this transition and align with guidance from other working groups. OBJECTIVES: To update and extend previous global ROSCO recommendations in line with the latest research and continue supporting uptake of the phenotype approach in rosacea through clinical tool development. METHODS: Nineteen dermatologists and two ophthalmologists used a modified Delphi approach to reach consensus on statements pertaining to critical aspects of rosacea diagnosis, classification and management. Voting was electronic and blinded. RESULTS: Delphi statements on which the panel achieved consensus of ≥ 75% voting 'Agree' or 'Strongly agree' are presented. The panel recommends discussing disease burden with patients during consultations, using four questions to assist conversations. The primary treatment objective should be achievement of complete clearance, owing to previously established clinical benefits for patients. Cutaneous and ocular features are defined. Treatments have been reassessed in line with recent evidence and the prior treatment algorithm updated. Combination therapy is recommended to benefit patients with multiple features. Ongoing monitoring and dialogue should take place between physician and patients, covering defined factors to maximize outcomes. A prototype clinical tool (Rosacea Tracker) and patient case studies have been developed from consensus statements. CONCLUSIONS: The current survey updates previous recommendations as a basis for local guideline development and provides clinical tools to facilitate a phenotype approach in practice and improve rosacea patient management. What's already known about this topic? A transition to a phenotype approach in rosacea is underway and is being recommended by multiple working groups. New research has become available since the previous ROSCO consensus, necessitating an update and extension of recommendations. What does this study add? We offer updated global recommendations for clinical practice that account for recent research, to continue supporting the transition to a phenotype approach in rosacea. We present prototype clinical tools to facilitate use of the phenotype approach in practice and improve management of patients with rosacea.
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Oftalmólogos , Rosácea , Terapia Combinada , Consenso , Costo de Enfermedad , Humanos , Rosácea/diagnóstico , Rosácea/terapiaRESUMEN
BACKGROUND: Rosacea diagnosis and classification have evolved since the 2002 National Rosacea Society expert panel subtype approach. Several working groups are now aligned to a more patient-centric phenotype approach, based on an individual's presenting signs and symptoms. However, subtyping is still commonplace across the field and an integrated strategy is required to ensure widespread progression to the phenotype approach. OBJECTIVES: To provide practical recommendations that facilitate adoption of a phenotype approach across the rosacea field. METHODS: A review of the literature and consolidation of rosacea expert experience. RESULTS: We identify challenges to implementing a phenotype approach in rosacea and offer practical recommendations to overcome them across clinical practice, interventional research, epidemiological research and basic science. CONCLUSIONS: These practical recommendations are intended to indicate the next steps in the progression from subtyping to a phenotype approach in rosacea, with the goals of improving our understanding of the disease, facilitating treatment developments and ultimately improving care for patients with rosacea.
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Investigación Biomédica/organización & administración , Dermatología/organización & administración , Atención Dirigida al Paciente/organización & administración , Rosácea/terapia , Investigación Biomédica/métodos , Dermatología/métodos , Progresión de la Enfermedad , Humanos , Atención Dirigida al Paciente/métodos , Fenotipo , Mejoramiento de la Calidad , Rosácea/diagnóstico , Rosácea/genética , Índice de Severidad de la EnfermedadRESUMEN
Disruption of the laminar and columnar organization of the brain is implicated in several psychiatric disorders. Here, we show in utero gain-of-function of the psychiatric risk gene transcription factor 4 (TCF4) severely disrupts the columnar organization of medial prefrontal cortex (mPFC) in a transcription- and activity-dependent manner. This morphological phenotype was rescued by co-expression of TCF4 plus calmodulin in a calcium-dependent manner and by dampening neuronal excitability through co-expression of an inwardly rectifying potassium channel (Kir2.1). For we believe the first time, we show that N-methyl-d-aspartate (NMDA) receptor-dependent Ca2+ transients are instructive to minicolumn organization because Crispr/Cas9-mediated mutation of NMDA receptors rescued TCF4-dependent morphological phenotypes. Furthermore, we demonstrate that the transcriptional regulation by the psychiatric risk gene TCF4 enhances NMDA receptor-dependent early network oscillations. Our novel findings indicate that TCF4-dependent transcription directs the proper formation of prefrontal cortical minicolumns by regulating the expression of genes involved in early spontaneous neuronal activity, and thus our results provides insights into potential pathophysiological mechanisms of TCF4-associated psychiatric disorders.
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Corteza Prefrontal/metabolismo , Factor de Transcripción 4/metabolismo , Factor de Transcripción 4/fisiología , Animales , Trastorno del Espectro Autista/genética , Trastorno del Espectro Autista/metabolismo , Encéfalo/patología , Neuronas/metabolismo , Corteza Prefrontal/embriología , Células Piramidales/metabolismo , Células Piramidales/fisiología , Ratas , Ratas Wistar , Receptores de N-Metil-D-Aspartato , Esquizofrenia/genética , Esquizofrenia/metabolismoRESUMEN
BACKGROUND: Contact allergy is a common condition and can severely interfere with daily life or professional activities. Due to changes in exposures, such as introduction of new substances, new products or formulations and regulatory intervention, the spectrum of contact sensitization changes. OBJECTIVE: To evaluate the current spectrum of contact allergy to allergens present in the European baseline series (EBS) across Europe. METHODS: Retrospective analysis of data collected by the European Surveillance System on Contact Allergies (ESSCA, www.essca-dc.org) in consecutively patch-tested patients, 2013/14, in 46 departments in 12 European countries. RESULTS: Altogether, 31 689 patients were included in the analysis. Compared to a similar analysis in 2004, the prevalence of contact allergy to methylisothiazolinone went up to around 20% in several departments. In comparison, contact allergy to the metals nickel, cobalt and chromium remained largely stable, at 18.1%, 5.9% and 3.2%, respectively, similar to mostly unchanged prevalence with fragrance mix I, II and Myroxylon pereirae (balsam of Peru) at 7.3%, 3.8% and 5.3%, respectively. In the subgroup of departments diagnosing (mainly) patients with occupational contact dermatitis, the prevalence of work-related contact allergies such as epoxy resin or rubber additives was found to be increased, compared to general dermatology departments. CONCLUSION: Continuous surveillance of contact allergy based on network data offers the identification of time trends or persisting problems, and thus enables focussing in-depth research (subgroup analyses, exposure analysis) on areas where it is needed.
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Dermatitis Alérgica por Contacto/epidemiología , Vigilancia de la Población , Adulto , Alérgenos/efectos adversos , Dermatitis Alérgica por Contacto/diagnóstico , Dermatitis Alérgica por Contacto/etiología , Europa (Continente)/epidemiología , Femenino , Humanos , Masculino , Metales Pesados/toxicidad , Persona de Mediana Edad , Prevalencia , Estudios RetrospectivosRESUMEN
BACKGROUND: Multiple studies have noted an association between hepatitis C and psoriasis, but it is not known whether psoriasis is a result of treatment modalities for hepatitis C or a result of hepatitis C alone. OBJECTIVE: To examine the relationship between psoriasis and hepatitis C by measuring the expression of cathelicidin, TLR9 and IFNγ in psoriatic lesional and non-lesional skin in HCV-positive and negative psoriatic patients. METHODS: Two 2 mm punch biopsies of lesional and non-lesional skin in 10 patients who were HCV-negative psoriatics and seven HCV-positive psoriatics were used to measure cathelicidin, TLR9 and IFNγ mRNA expression by quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR). RESULTS: The mRNA levels of cathelicidin, TLR9 and IFNγ were significantly higher in both non-lesional and lesional skin of HCV-positive patients with psoriasis as compared to HCV-negative psoriatic patients. Additionally, the IFNγ level in lesional skin of HCV-positive psoriatic patients was higher than the IFNγ level seen in non-lesional skin of those same patients. CONCLUSION: These findings suggest that HCV infection upregulates these inflammatory cytokines, possibly increasing susceptibility to developing psoriasis.
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Péptidos Catiónicos Antimicrobianos/genética , Hepatitis C/genética , Interferón gamma/genética , Psoriasis/genética , ARN Mensajero/metabolismo , Receptor Toll-Like 9/genética , Adulto , Femenino , Expresión Génica , Hepatitis C/complicaciones , Hepatitis C/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Psoriasis/complicaciones , Psoriasis/metabolismo , Piel/metabolismo , CatelicidinasRESUMEN
BACKGROUND: Rosacea is currently diagnosed by consensus-defined primary and secondary features and managed by subtype. However, individual features (phenotypes) can span multiple subtypes, which has implications for clinical practice and research. Adopting a phenotype-led approach may facilitate patient-centred management. OBJECTIVES: To advance clinical practice by obtaining international consensus to establish a phenotype-led rosacea diagnosis and classification scheme with global representation. METHODS: Seventeen dermatologists and three ophthalmologists used a modified Delphi approach to reach consensus on statements pertaining to critical aspects of rosacea diagnosis, classification and severity evaluation. All voting was electronic and blinded. RESULTS: Consensus was achieved for transitioning to a phenotype-based approach to rosacea diagnosis and classification. The following two features were independently considered diagnostic for rosacea: (i) persistent, centrofacial erythema associated with periodic intensification; and (ii) phymatous changes. Flushing, telangiectasia, inflammatory lesions and ocular manifestations were not considered to be individually diagnostic. The panel reached agreement on dimensions for phenotype severity measures and established the importance of assessing the patient burden of rosacea. CONCLUSIONS: The panel recommended an approach for diagnosis and classification of rosacea based on disease phenotype.
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Oftalmopatías/diagnóstico , Rosácea/diagnóstico , Índice de Severidad de la Enfermedad , Edad de Inicio , Consenso , Costo de Enfermedad , Dermatitis/etiología , Dermatólogos , Oftalmopatías/clasificación , Humanos , Cooperación Internacional , Estilo de Vida , Oftalmólogos , Planificación de Atención al Paciente , Rosácea/clasificación , Pigmentación de la Piel/fisiología , Telangiectasia/etiologíaRESUMEN
BACKGROUND AND OBJECTIVES: Obesity is a global epidemic which increases the risk of the metabolic syndrome. Cathelicidin (LL-37 and mCRAMP) is an antimicrobial peptide with an unknown role in obesity. We hypothesize that cathelicidin expression correlates with obesity and modulates fat mass and hepatic steatosis. MATERIALS AND METHODS: Male C57BL/6 J mice were fed a high-fat diet. Streptozotocin was injected into mice to induce diabetes. Experimental groups were injected with cathelicidin and CD36 overexpressing lentiviruses. Human mesenteric fat adipocytes, mouse 3T3-L1 differentiated adipocytes and human HepG2 hepatocytes were used in the in vitro experiments. Cathelicidin levels in non-diabetic, prediabetic and type II diabetic patients were measured by enzyme-linked immunosorbent assay. RESULTS: Lentiviral cathelicidin overexpression reduced hepatic steatosis and decreased the fat mass of high-fat diet-treated diabetic mice. Cathelicidin overexpression reduced mesenteric fat and hepatic fatty acid translocase (CD36) expression that was reversed by lentiviral CD36 overexpression. Exposure of adipocytes and hepatocytes to cathelicidin significantly inhibited CD36 expression and reduced lipid accumulation. Serum cathelicidin protein levels were significantly increased in non-diabetic and prediabetic patients with obesity, compared with non-diabetic patients with normal body mass index (BMI) values. Prediabetic patients had lower serum cathelicidin protein levels than non-diabetic subjects. CONCLUSIONS: Cathelicidin inhibits the CD36 fat receptor and lipid accumulation in adipocytes and hepatocytes, leading to a reduction of fat mass and hepatic steatosis in vivo. Circulating cathelicidin levels are associated with increased BMI. Our results demonstrate that cathelicidin modulates the development of obesity.
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Péptidos Catiónicos Antimicrobianos/farmacología , Hígado Graso/tratamiento farmacológico , Hígado Graso/prevención & control , Metabolismo de los Lípidos/efectos de los fármacos , Células 3T3-L1 , Adipocitos/citología , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Animales , Antígenos CD36/biosíntesis , Antígenos CD36/genética , Diferenciación Celular/efectos de los fármacos , Diabetes Mellitus Experimental , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Hígado Graso/complicaciones , Hígado Graso/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Humanos , Inmunohistoquímica , Hígado/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Obesidad/complicaciones , Obesidad/metabolismo , Estado Prediabético/complicaciones , Estado Prediabético/metabolismo , CatelicidinasRESUMEN
BACKGROUND: Organ transplantation in Brazil is increasing, but one of its current obstacles is the negative response of the population to organ donation. Therefore, to make the process viable, it is essential that people are educated in organ donation and transplantation. The purpose of this research was to evaluate the main doubts on this subject and to clarify these issues by educating the respondents on the basis of their questions. METHODS: Handout questionnaires about organ donation and transplantation were distributed in public schools. The public targets were parents, teachers, and students. The interviewers were trained medical students. RESULTS: In this pilot study with 293 subjects, 97% of respondents had already heard about organ donation; 81% said they would donate their organs, whereas 76% said they would donate the organs of family members and 78% said they believe in the existence of organ trafficking in Brazil. CONCLUSIONS: The high percentage of respondents believing in the existence of an organ trade highlights the urgency in clarifying this topic. To do so, the population must be educated about the ethics of the process of donation, emphasizing the fact that there is no organ trade in Brazil.
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Educación Médica/métodos , Trasplante de Órganos/educación , Educación del Paciente como Asunto , Estudiantes de Medicina , Obtención de Tejidos y Órganos , Brasil , Femenino , Humanos , Masculino , Proyectos PilotoRESUMEN
BACKGROUND: Data on the epidemiological impact and clinical characteristics of chronic hand eczema in Southern Europe are lacking. OBJECTIVES: To estimate the prevalence of chronic hand eczema in its different stages of severity and refractoriness to standard therapy in patients accessing Italian dermatological reference centres, and to evaluate sociodemographic and clinical factors associated with each stage. METHODS: A cross-sectional multicentre study was conducted. Adult patients with hand eczema, consecutively accessing 14 centres over a 6-month period, were enrolled. Patients were classified according to disease duration, severity and response to standard therapy with potent topical corticosteroids. Logistical regression was performed to investigate the relationship between sociodemographic and clinical data with different stages of eczema. RESULTS: The total number of participants was 981. Hand eczema was chronic in 83·5% of patients; 21·3% had severe eczema, with 62·0% of these patients refractory to standard therapy. Food processing and related work, the health professions, craft and related trade works (building, plumbing, electrical), hairdressing/beauty and handicraft work were most frequently associated with chronic hand eczema. Severe chronic hand eczema was more likely to be seen in men, older patients and those with less education. Severe and refractory hand eczema was also more likely among the unemployed and patients with allergic rhinitis and/or atopic dermatitis. CONCLUSIONS: Chronic hand eczema is frequent among patients with hand eczema accessing dermatology centres. Many patients were severe and refractory to standard therapy. The appropriate identification of hand eczema is the first step in implementing effective and efficient treatments.
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Eccema/epidemiología , Dermatosis de la Mano/epidemiología , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Estudios Transversales , Dermatitis Profesional/epidemiología , Dermatitis Profesional/terapia , Eccema/terapia , Femenino , Dermatosis de la Mano/terapia , Humanos , Italia/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Distribución por Sexo , Factores Socioeconómicos , Adulto JovenRESUMEN
BACKGROUND: Persistent or "de novo" anemia (plasma hemoglobin<11 g/dL) may complicate the graft outcome in a significant number of renal transplant recipients. We describe a single-center experience with epoetin-zeta (EPO-Z), the biosimilar form for epoetin-alfa. METHODS: Twenty patients were included in the study, 10 in treatment with different erythropoiesis-stimulating agents (ESA) and shifted to EPO-Z (shift group) and 10 who started EPO-Z treatment for anemia (naive group). All the patients had stable renal function and normal values of main inflammation markers and were prospectively followed up for 12 months. Iron supplements were administered during the study, as needed. RESULTS: In the shift group, mean plasma hemoglobin levels>11 g/dL were maintained for the entire 1-year follow-up period, with average EPO-Z doses 3.4% higher than the corresponding doses of previous ESA; in the naive group, the target value was reached between the first and third months and remained stable throughout the study. Mean corpuscular volume did not vary in either group. No change was observed in glomerular filtration rate, nor in proteinuria or in main laboratory data. No drug-related side effect was reported. CONCLUSIONS: EPO-Z may be considered a valid alternative to different ESAs in renal transplant recipients, with an interesting pharmaco-economic profile, considering its lower cost.
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Anemia/tratamiento farmacológico , Eritropoyetina/uso terapéutico , Hematínicos/uso terapéutico , Trasplante de Riñón , Receptores de Trasplantes , Epoetina alfa , Eritropoyetina/economía , Femenino , Estudios de Seguimiento , Hematínicos/economía , Hemoglobinas/análisis , Humanos , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Proteínas Recombinantes/economía , Proteínas Recombinantes/uso terapéuticoRESUMEN
Neuropathic pain is a chronic, refractory condition that arises after damage to the nervous system. We previously showed that an increased level of the endogenous metabolite N,N-dimethylsphingosine (DMS) in the central nervous system (CNS) is sufficient to induce neuropathic pain-like behavior in rats. However, several important questions remain. First, it has not yet been demonstrated that DMS is produced in humans and its value as a therapeutic target is therefore unknown. Second, the cell types within the CNS that produce DMS are currently unidentified. Here we provide evidence that DMS is present in human CNS tissue. We show that DMS levels increase in demyelinating lesions isolated from patients with multiple sclerosis, an autoimmune disease in which the majority of patients experience chronic pain. On the basis of these results, we hypothesized that oligodendrocytes may be a cellular source of DMS. We show that human oligodendrocytes produce DMS in culture and that the levels of DMS increase when oligodendrocytes are challenged with agents that damage white matter. These results suggest that damage to oligodendrocytes leads to increased DMS production which in turn drives inflammatory astrocyte responses involved in sensory neuron sensitization. Interruption of this pathway in patients may provide analgesia without the debilitating side effects that are commonly observed with other chronic pain therapies.
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Oligodendroglía/inmunología , Esfingosina/análogos & derivados , Animales , Astrocitos/inmunología , Línea Celular , Humanos , Esclerosis Múltiple/inmunología , Fosfotransferasas (Aceptor de Grupo Alcohol)/antagonistas & inhibidores , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Ratas , Esfingosina/metabolismoRESUMEN
Previously, we demonstrated that Propionibacterium acnes, a human skin commensal bacterium, ferments glycerol into short-chain fatty acids, including propionic acid. Propionic acid suppressed the growth of Staphylococcus aureus USA300, a community-acquired methicillin-resistant bacterium, in vitro and in vivo. In this study, it is demonstrated that the anti-USA300 activity of propionic acid persisted after buffering the acid with 4-(2-hydroxyethyl)-1- piperazineethanesulfonic acid. This suggests that the growth suppression of USA300 mainly resulted from the antimicrobial activity of propionic acid per se and not from the acidity of the medium. In addition, proprionic acid significantly reduced the intracellular pH of USA300 and exhibited broad-spectrum antimicrobial activity against Escherichia coli and Candida albicans. P. acnes showed a higher tolerance to propionic acid. Next, an esterified derivative of propionic acid was synthesised. Propionic acid and the esterified derivative were equivalent in their efficacy to suppress the growth of USA300 in vitro. The esterified derivative thus provides an alternative to propionic acid as an antimicrobial agent against S. aureus.