What do Hyperhidrosis Quality of Life Index (HidroQoL©) scores mean? Transferring science into practice by establishing a score banding system.

BACKGROUND: The Hyperhidrosis Quality of Life Index (HidroQoL©) is a measure of quality of life (QoL) impacts in hyperhidrosis (HH). OBJECTIVES: We aimed to establish score banding systems for the HidroQoL total score for specific contexts representing different severity/impact categories by using the Dermatology Life Quality Index (DLQI) and the Hyperhidrosis Disease Severity Scale (HDSS) as anchors, including data from 357 patients from a phase III clinical trial. METHODS: We used the HDSS, the established DLQI score bands and two single items (items 5 and 7) of the DLQI as anchors for the creation of banding systems for the HidroQoL. These anchors were chosen via consensus among an expert group according to relevance to patient experience. Due to the distribution of the HDSS and the single DLQI item 7, receiver operating characteristic curves were computed in order to create an optimal cut-off value of the HidroQoL total score. For the DLQI banding system and the single DLQI item 5, we created a banding system for the HidroQoL based on the distribution of their different categories. RESULTS: A score of 30 and greater is proposed as the cut-off value for sweating that 'always interferes in daily activities', based on the HDSS as anchor. In terms of overall skin QoL effects, score bands of 0-6, 7-18, 19-25, 26-32 and 33-36 represent 'no effect', 'small effect', 'moderate effect', 'very large effect' and 'extremely large effect' on the patient's life, respectively. CONCLUSIONS: In this study, we propose different banding systems for four different contexts: skin-specific QoL (DLQI banding), HH severity (HDSS), working and studying (single DLQI item 7) and social and leisure activities (single DLQI item 5). These banding systems and cut-off values can be used in clinical research and practice to place the patients in different severity categories.

Long-term efficacy and safety of 1% glycopyrronium bromide cream in patients with severe primary axillary hyperhidrosis: Results from a Phase 3b trial.

BACKGROUND: Primary axillary hyperhidrosis (PAHH) strongly affects the patient's quality of life. To date, topical treatment options are limited. One percent glycopyrronium bromide (GPB) showed promising efficacy and safety in a pivotal 4-week Phase 3a study. OBJECTIVES: To assess efficacy and safety of topical 1% GPB cream in patients with severe PAHH in a long-term study of 72 weeks versus baseline. METHODS: This was a long-term, open-label, Phase 3b trial for 72 weeks including 518 patients with severe PAHH. Patients were treated with 1% GPB cream once daily for 4 weeks, followed by a flexible dosing scheme (min. twice per week, max. once daily). Primary endpoint was the absolute change in sweat production from baseline to week 12. Further study endpoints included assessment of the severity of PAHH and the impact on quality of life. RESULTS: Total median sweat production decreased by 119.30 mg (-65.6%, both median) until week 12. Absolute change in sweat production from baseline to week 12 in logarithmic values was statistically significant (p < 0.0001). Patients' quality of life was improved at all study time points compared to baseline, as assessed by Hyperhidrosis Quality of Life Index and Dermatology Life Quality Index (p < 0.0001). Treatment was safe and locally well-tolerated with only few mild to moderate adverse drug reactions (ADRs). Dry mouth and application site erythema were the most common reported ADRs. CONCLUSIONS: Treatment with 1% GPB cream over 72 weeks significantly reduces sweat production and improves quality of life in patients with severe PAHH. One percent GPB cream is well-tolerated and provides an effective treatment option for long-term use in patients with severe PAHH.

Pharmacology, toxicology and clinical safety of glycopyrrolate.

The clinical use of the anticholinergic glycopyrrolate dates back to the early 1960s when it was first approved in the U.S. Since then, oral and inhalation formulations have been developed as therapeutic agents inhibiting the muscarinic acetylcholine receptor in various indications including chronic obstructive pulmonary disease (COPD), excessive salivation, and peptic ulcers. More recently, topical formulations of glycopyrrolate (GPB, also known as glycopyrronium bromide) have gained interest as a treatment option for excessive sweating (hyperhidrosis). The U.S. Food and Drug Administration (FDA) approved the first topical glycopyrronium product for the treatment of hyperhidrosis in 2018. Glycopyrrolate, as a quaternary amine, shows minimal penetration of the blood brain barrier which limits CNS side effects. In addition, lack of phototoxicity, genotoxicity and carcinogenicity makes it suitable for chronic indications. The information on the nonclinical and clinical safety profile of glycopyrronium supporting various therapeutically approved uses has been obtained from published literature, our own data as well as summary documents issued by regulatory bodies. Collectively, these data support the conclusion that the benefits of glycopyrronium generally outweigh the risks in chronic use indications that require muscarinic receptor antagonism to provide therapeutic effects.

An effective non-hormonal option with high tolerability for mild to moderate symptoms of vaginal dryness associated with menopause.

OBJECTIVES: The efficacy and tolerability of a non-hormonal pessary (that forms an oil-in-water emollient with the vaginal fluid) were assessed for the treatment of symptoms of vaginal dryness associated with menopause. STUDY DESIGN: Seventy-nine postmenopausal women (mean age 60.8 ± 6.5 years) with mild to moderate symptoms of vaginal dryness (including dyspareunia) were enrolled in this open-label, prospective, post-market clinical follow-up trial, conducted in 2022 by one research center in Germany. The investigational pessary was applied for the first 7 days once daily and the subsequent 31 days twice a week, at bedtime. A treatment-free period of 6 days completed the trial. MAIN OUTCOME MEASURES: During the trial, participants filled out questionnaires that enabled the calculation of a total severity score for subjective symptoms of atrophy-related vaginal dryness and impairment of daily as well as sexual life. Furthermore, vaginal health index and safety were studied. RESULTS: A rapid and significant reduction in the severity scores for symptoms was observed over the 38-day course of treatment and beyond. Quality of life assessed by DIVA (day-to-day impact of vaginal aging) questionnaire, dyspareunia and vaginal health index also clearly improved. The tolerability was mainly rated as "good to very good" by the investigator and 94.9 % of participants. The vast majority were very satisfied with the simple and pleasant handling. No serious adverse events occurred. CONCLUSION: Overall, the presented data suggest that the investigated non-hormonal pessary is an effective and well tolerated treatment option for vaginal symptoms associated with dryness, thus improving quality of life for women, even those who are sexually active. CLINICALTRIALS: gov identifier NCT05211505.

Psychometric evaluation of the German Day-to-Day Impact of Vaginal Aging questionnaire using data from two intervention studies.

OBJECTIVE: We aimed to further validate the German version of the Day-to-Day Impact of Vaginal Aging (DIVA) questionnaire. METHODS: Data were collected in the context of two intervention studies. Forty-two women participated in clinical trial VMP-03/2018 (NCT04222647) and 79 women in clinical trial VFCrC-01/2021 (NCT05211505). Internal consistency was calculated using Cronbach α . Correlations with other outcome measures such as a subjective assessment of symptoms and dyspareunia, the Vaginal Health Index, and the Vaginal Maturation Index were calculated regarding construct validity. A priori hypotheses were formulated for construct validity. Responsiveness was assessed after 43 (±3) and after 38 (±1) days in the two clinical trials. RESULTS: Strong internal consistency in all of the DIVA domains was found ( α ≥ 0.80). Regarding construct validity (at baseline and over time), many hypotheses were confirmed. Furthermore, all of the DIVA domains were able to detect changes over time ( P ≤ 0.006). Moderate to strong effect sizes were found (≥0.460). The data supported the responsiveness of the DIVA. CONCLUSIONS: Our findings from two independent intervention studies support internal consistency, construct validity, and responsiveness of the German version of the DIVA (domains).

Hyperhidrosis quality of life index (HidroQoL): further validation by applying classical test theory and item response theory using data from a phase III clinical trial.

BACKGROUND: The Hyperhidrosis Quality of Life Index (HidroQoL ©) is a well-developed and validated patient-reported outcome measure assessing the quality-of-life impacts in hyperhidrosis with 18 items. Our aim was to extend the already existing validity evidence for the HidroQoL, especially in relation to structural validity. Especially Rasch analysis has not been applied to the final 18-item HidroQoL before. METHODS: Data from a phase III clinical trial were used. Confirmatory factor analysis was conducted to confirm the two a priori HidroQoL scales within classical test theory. Furthermore, the assumptions of the Rasch model (model fit, monotonicity, unidimensionality, local independence) and Differential Item Functioning (DIF) were assessed using item response theory. RESULTS: The sample included 529 patients with severe primary axillary hyperhidrosis. The two-factor structure could be confirmed by the confirmatory factor analysis (SRMR = 0.058). The item characteristic curves showed mainly optimally functioning response categories, indicating monotonicity. The overall fit to the Rasch model was adequate and unidimensionality for the HidroQoL overall scale could be confirmed, since the first factor had an eigenvalue of 2.244 and accounted for 18.7%. Local independence was below assumed thresholds (residual correlations ≤ 0.26). DIF analysis, controlling for age or gender, was critical for four and three items, respectively. However, this DIF could be explained. CONCLUSION: Using classical test theory and item response theory/Rasch analyses, this study provided further evidence for the structural validity of the HidroQoL. This study confirmed several specific (measurement) properties of the HidroQoL questionnaire in patients with physician-confirmed severe primary axillary hyperhidrosis: the HidroQoL is a unidimensional scale allowing the summation of scores to generate a single score, and simultaneously it has a dual structure, also allowing the calculation of separate domain scores for daily activities and psychosocial impacts. With this study, we provided new evidence of the structural validity of the HidroQoL in the context of a clinical trial. Trial registration The study was registered (ClinicalTrials.gov identifier: NCT03658616, 05 September 2018, https://clinicaltrials.gov/ct2/show/NCT03658616?term=NCT03658616&draw=2&rank=1 ).

Vaginal hormone-free moisturising cream is not inferior to an estriol cream for treating symptoms of vulvovaginal atrophy: Prospective, randomised study.

This prospective, open-label, multicentre, multinational, randomised trial investigated the non-inferiority of treatment with a vaginal hormone-free moisturising cream compared to a vaginal estriol (0.1%) cream in a panel of post-menopausal women suffering from symptoms of vulvovaginal dryness in a parallel group design. In total, 172 post-menopausal women were randomly allocated to either one of the two treatments, each administered for 43 days. The primary endpoint was the total severity score of subjective symptoms (dryness, itching, burning and pain unrelated to sexual intercourse) of the respective treatment period. Secondary endpoints were severity of single subjective symptoms (including dyspareunia if sexually active), impairment of daily life, Vaginal Health Index, as well as assessment of safety. In both groups, women treated with hormone-free moisturising cream and those treated with estriol cream, total severity score improved significantly compared to baseline by 5.0 (from 6.1 to 1.1) and by 5.4 (from 6.0 to 0.6), respectively, after 43 days of treatment (p < 0.0001). One-sided test of baseline differences (for a clinically relevant difference Δ = 1.5) confirmed the hormone-free moisturising cream to be non-inferior to the estriol cream. Severity of dyspareunia as well as impairment of daily life due to subjective symptoms, significantly improved for both treatment groups (p<0.0001). Subgroup analysis of women with mild or moderate impairment of daily life at baseline caused by "vaginal dryness" symptoms benefited from both creams, while women with severe impairment showed a significantly greater benefit from the estriol cream (p = 0.0032). Both treatments were well tolerated with no serious adverse events occurring. This study provides clinical evidence that a hormone-free vaginal moisturising cream cannot only improve vaginal dryness compared to an 0.1% estriol cream but also can relieve dyspareunia as well as improve woman's impairment of daily life, justifying its use as a first choice for mild or moderate vulvovaginal dryness symptoms.

Imbalanced lignin biosynthesis promotes the sexual reproduction of homothallic oomycete pathogens.

Lignin is incorporated into plant cell walls to maintain plant architecture and to ensure long-distance water transport. Lignin composition affects the industrial value of plant material for forage, wood and paper production, and biofuel technologies. Industrial demands have resulted in an increase in the use of genetic engineering to modify lignified plant cell wall composition. However, the interaction of the resulting plants with the environment must be analyzed carefully to ensure that there are no undesirable side effects of lignin modification. We show here that Arabidopsis thaliana mutants with impaired 5-hydroxyguaiacyl O-methyltransferase (known as caffeate O-methyltransferase; COMT) function were more susceptible to various bacterial and fungal pathogens. Unexpectedly, asexual sporulation of the downy mildew pathogen, Hyaloperonospora arabidopsidis, was impaired on these mutants. Enhanced resistance to downy mildew was not correlated with increased plant defense responses in comt1 mutants but coincided with a higher frequency of oomycete sexual reproduction within mutant tissues. Comt1 mutants but not wild-type Arabidopsis accumulated soluble 2-O-5-hydroxyferuloyl-L-malate. The compound weakened mycelium vigor and promoted sexual oomycete reproduction when applied to a homothallic oomycete in vitro. These findings suggested that the accumulation of 2-O-5-hydroxyferuloyl-L-malate accounted for the observed comt1 mutant phenotypes during the interaction with H. arabidopsidis. Taken together, our study shows that an artificial downregulation of COMT can drastically alter the interaction of a plant with the biotic environment.

Topical treatment of vaginal dryness with a non-hormonal cream in women undergoing breast cancer treatment - An open prospective multicenter study.

This open, prospective, multicenter, observational study was performed to investigate the efficacy and safety of a non-hormonal cream in women undergoing breast cancer treatment and experiencing vulvovaginal dryness symptoms. Overall, 128 patients from 22 study centers participated. The cream was applied to the vagina and vulva for 28 days. For the efficacy analysis, changes in subjective symptoms (feeling of dryness, itching, burning, pain independent of sexual intercourse, dyspareunia, urinary incontinence) were evaluated. Additionally, the following objective diagnostic findings were assessed by a physician: thinning of vaginal epithelium, redness, petechiae, and discharge. Safety and tolerability were assessed by evaluating type and frequency of adverse events, including adverse medical device-related effects. The frequency and intensity of all subjective symptoms significantly improved from baseline at 28 days (p<0.0001). Additionally, 21.4% of patients were completely free of symptoms (p<0.0001) and urinary incontinence was improved or eliminated in 30.8% of women. The overall sum score for all four objective findings was significantly improved from baseline at 28 days (p<0.0001). The frequency of petechial bleedings was significantly reduced (p<0.0001). Further, significant decreases in the severity of vaginal epithelium thinning, redness and petechiae were observed (p<0.0001). More than 88% of patients and investigators assessed the efficacy and tolerability as being good or very good. No serious adverse events were documented. This study demonstrates that the investigated cream is an effective and safe non-hormonal, topical option in the treatment of vulvovaginal dryness symptoms in patients undergoing breast cancer treatment for. However, the study duration and follow-up time of 4 weeks as well as the non-randomized trial design are limitations of the study.

Skin acidification with a water-in-oil emulsion (pH 4) restores disrupted epidermal barrier and improves structure of lipid lamellae in the elderly.

The pH of the skin surface increases with age and thus reduces epidermal barrier function. Aged skin needs appropriate skin care to counterbalance age-related pH increase and improve barrier function. This confirmatory randomized study investigated the efficacy of water-in-oil (w/o) emulsions with either pH 4 or pH 5.8 in 20 elderly subjects after 4 weeks of treatment. After the treatment, the skin was challenged with a sodium dodecyl sulphate (SDS) solution in order to analyze barrier protection properties of both formulations. The pH 4 w/o emulsion resulted in a significantly lower skin pH compared with the pH 5.8 w/o emulsion and an improved skin hydration after 4-week treatment. Further, the pH 4 emulsion led to more pronounced improvements in length of intercellular lipid lamellae, lamellar organization as well as lipid levels than the pH 5.8 emulsion. Following SDS-induced barrier damage to the skin, the pH of all test areas increased, but the area treated with the pH 4 emulsion showed the lowest increase compared with baseline. In addition, even after the SDS challenge the skin area treated with the pH 4 emulsion still maintained a significantly increased length of intercellular lipid lamellae compared with the beginning of the study. This study provides evidence that topical application of a w/o emulsion with pH 4 reacidifies the skin in elderly and has beneficial effects on skin moisturization, regeneration of lipid lamellae and lipid content. Application of a pH 4 emulsion can improve the epidermal barrier as well as the stratum corneum organization in aged skin.

Efficacy of hydrophilic or lipophilic emulsions containing Echinacea purpurea extract in treatment of different types of pruritus.

BACKGROUND: Pruritus reduces quality of life and may occur at different sites of the body. To alleviate pruritus, lipid replenishing and rehydration of the skin is often unsatisfactory. Thus, products with additional antipruritic effects are needed. OBJECTIVES: Antipruritic effects and cosmetic properties of two different emulsions, water-in-oil (w/o) or oil-in-water (o/w), and a shampoo containing a lipophilic Echinacea purpurea root extract (Ec.-extract) were assessed in adults suffering from pruritus. METHODS: Adults (n = 55) with pruritus of the body applied a w/o emulsion for 2 weeks. In a separate study, adults (n = 33) with a pruritic scalp applied an o/w-emulsion for 4 weeks. In a third study, shampoo (n = 34) was applied for 4 weeks. Objective (erythema, dryness, and papules) and subjective (intensity, duration, and burden of pruritus) parameters were assessed. RESULTS: Treatment with the w/o emulsion significantly reduced erythema and dryness (P < 0.0001) as well as pruritus (in 93% of participants) on the body. Treatment with the o/w-emulsion on the scalp significantly (P < 0.0001) reduced objective (erythema in 61% and dryness in 85% of participants) and subjective (85% of participants had reduced pruritus) parameters. Similar results in reduction of dryness (76% of participants) and pruritus (70 % of participants) were seen after 4 weeks of shampoo use. CONCLUSION: Independent from the type of emulsion (w/o or o/w), cosmetic products containing a proprietary Ec.-extract significantly reduced objective and subjective parameters in adults suffering from acute or chronic pruritus exhibiting excellent tolerability.

Metatranscriptome Analysis of the Vaginal Microbiota Reveals Potential Mechanisms for Protection against Metronidazole in Bacterial Vaginosis.

Bacterial vaginosis (BV) is a prevalent multifactorial disease of women in their reproductive years characterized by a shift from the Lactobacillus species-dominated microbial community toward a taxonomically diverse anaerobic community. For unknown reasons, some women do not respond to therapy. In our recent clinical study, among 37 women diagnosed with BV, 31 were successfully treated with metronidazole, while 6 still had BV after treatment. To discover possible reasons for the lack of response in those patients, we performed a metatranscriptome analysis of their vaginal microbiota, comparing them to the patients who responded. Seven of 8 clustered regularly interspaced short palindromic repeat (CRISPR)-associated (Cas) genes of Gardnerella vaginalis were highly upregulated in nonresponding patients. Cas genes, in addition to protecting against phages, might be involved in DNA repair, thus mitigating the bactericidal effect of DNA-damaging agents such as metronidazole. In the second part of our study, we analyzed the vaginal metatranscriptomes of four patients over 3 months and showed high in vivo expression of genes for pore-forming toxins in L. iners and of genes encoding enzymes for the production of hydrogen peroxide and d-lactate in L. crispatusIMPORTANCE Bacterial vaginosis is a serious issue for women in their reproductive years. Although it can usually be cured by antibiotics, the recurrence rate is very high, and some women do not respond to antibiotic therapy. The reasons for that are not known. Therefore, we undertook a study to detect the activity of the complete microbiota in the vaginal fluid of women who responded to antibiotic therapy and compared it to the activity of the microbiota in women who did not respond. We found that one of the most important pathogens in bacterial vaginosis, Gardnerella vaginalis, has activated genes that can repair the DNA damage caused by the antibiotic in those women that do not respond to therapy. Suppressing these genes might be a possibility to improve the antibiotic therapy of bacterial vaginosis.

The urinary microbiota of men and women and its changes in women during bacterial vaginosis and antibiotic treatment.

BACKGROUND: The urinary microbiota is similarly complex as the vaginal and penile microbiota, yet its role as a reservoir for pathogens and for recurrent polymicrobial biofilm diseases like bacterial vaginosis (BV) is not clear. RESULTS: Here, we analysed the urinary microbiota of healthy men and women and compared it with that of women during BV and after antibiotic treatment using next-generation sequencing of the 16S rRNA gene V1-V2 regions. Eight different community types, so called urotypes (UT), were identified in healthy humans, all of which were shared between men and women, except UT 7, dominated in relative abundance by Lactobacillus crispatus, which was found in healthy women only. Orally applied metronidazole significantly reduced Shannon diversity and the mean relative abundance of Gardnerella vaginalis, Atopobium vaginae, and Sneathia amnii, while L. iners increased to levels twofold higher than those found in healthy women. Although individual urine microbial profiles strongly responded to the antibiotic, the healthy community could not be restored. The correlation between urinary and vaginal fluid microbiota was generally weak and depending on UT and BV status. It was highest in UT 1 in acute BV (59% of samples), but after metronidazole treatment, only 3 out of 35 women showed a significant correlation between their urinary and vaginal microbiota composition. CONCLUSIONS: Urethra and bladder thus harbor microbial communities distinct from the vagina. The high abundance of BV related species in the urine of both men and women suggests that urine may act as a reservoir of pathogens and contribute to recurrence. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02687789.

Treatment of biofilms in bacterial vaginosis by an amphoteric tenside pessary-clinical study and microbiota analysis.

BACKGROUND: Bacterial vaginosis (BV) is the most common vaginal syndrome among women in their reproductive years. It is associated with an increased risk of acquiring sexually transmitted infections and complications like preterm labor. BV is characterized by a high recurrence rate for which biofilms frequently found on vaginal epithelial cells may be a reason. RESULTS: Here, we report a controlled randomized clinical trial that tested the safety and effectiveness of a newly developed pessary containing an amphoteric tenside (WO3191) to disrupt biofilms after metronidazole treatment of BV. Pessaries containing lactic acid were provided to the control group, and microbial community composition was determined via Illumina sequencing of the V1-V2 region of the 16S rRNA gene. The most common community state type (CST) in healthy women was characterized by Lactobacillus crispatus. In BV, diversity was high with communities dominated by either Lactobacillus iners, Prevotella bivia, Sneathia amnii, or Prevotella amnii. Women with BV and proven biofilms had an increased abundance of Sneathia sanguinegens and a decreased abundance of Gardnerella vaginalis. Following metronidazole treatment, clinical symptoms cleared, Nugent score shifted to Lactobacillus dominance, biofilms disappeared, and diversity (Shannon index) was reduced in most women. Most of the patients responding to therapy exhibited a L. iners CST. Treatment with WO 3191 reduced biofilms but did not prevent recurrence. Women with high diversity after antibiotic treatment were more likely to develop recurrence. CONCLUSIONS: Stabilizing the low diversity healthy flora by promoting growth of health-associated Lactobacillus sp. such as L. crispatus may be beneficial for long-term female health. TRIAL REGISTRATION: ClinicalTrials.gov NCT02687789.

Screening of Compounds against Gardnerella vaginalis Biofilms.

Bacterial vaginosis (BV) is a common infection in reproductive age woman and is characterized by dysbiosis of the healthy vaginal flora which is dominated by Lactobacilli, followed by growth of bacteria like Gardnerella vaginalis. The ability of G. vaginalis to form biofilms contributes to the high rates of recurrence that are typical for BV and which unfortunately make repeated antibiotic therapy inevitable. Here we developed a biofilm model for G. vaginalis and screened a large spectrum of compounds for their ability to prevent biofilm formation and to resolve an existing G. vaginalis biofilm. The antibiotics metronidazole and tobramycin were highly effective in preventing biofilm formation, but had no effect on an established biofilm. The application of the amphoteric tenside sodium cocoamphoacetate (SCAA) led to disintegration of existing biofilms, reducing biomass by 51% and viability by 61% and it was able to increase the effect of metronidazole by 40% (biomass) and 61% (viability). Our data show that attacking the biofilm and the bacterial cells by the combination of an amphoteric tenside with the antibiotic metronidazole might be a useful strategy against BV.

A role for a flavin-containing mono-oxygenase in resistance against microbial pathogens in Arabidopsis.

Using activation tagging in the Arabidopsis Col-0 rps2-101C background, we identified a mutant (FMO1-3D) that showed virtually no symptoms after inoculation with virulent Pseudomonas syringae pv. tomato DC3000 bacteria. The dominant, gain-of-function phenotype of the FMO1-3D mutant is due to over-expression of a class 3 flavin-containing mono-oxygenase (FMO). We recapitulated the FMO1-3D mutant phenotype in independent transgenic Col-0 lines over-expressing the FMO1 cDNA under the control of the 35S CaMV promoter. The increased basal resistance observed in the FMO1-3D mutant was also effective against the taxonomically unrelated downy mildew-causing pathogen Hyaloperonospora parasitica. By investigating the progeny from crosses of the FMO1-3D mutant with the NahG transgenic line, we showed that the enhanced basal resistance phenotype was dependent on the accumulation of salicylic acid. FMO1-3D plants showed wild-type resistant reactions after inoculation with avirulent bacteria, indicating that the R-gene-mediated defence physiology was not compromised by FMO1 over-expression. Transcripts of the class 3 FMO1 gene accumulated within 6 h after inoculation of wild-type Col-0 plants with avirulent Pst + avrRpt2 cells. Moreover, a T-DNA insertion into the FMO1 gene resulted in enhanced susceptibility to virulent Pseudomonas and Hyaloperonospora parasitica, suggesting that expression of the FMO1 gene is a hitherto undescribed component of the plant's resistance repertoire. We discuss the possibility that the FMO may participate in the detoxification of virulence factors produced by pathogens.