A phase II/III randomized clinical trial of CisPlatin plUs Gemcitabine and Nabpaclitaxel (GAP) as pReoperative chemotherapy versus immediate resection in patIents with resecTable BiliarY Tract Cancers (BTC) at high risk for recurrence: PURITY study.

BACKGROUND: Biliary tract cancers (BTCs) are rare and lethal cancers, with a 5-year survival inferior to 20%(1-3). The only potential curative treatment is surgical resection. However, despite complex surgical procedures that have a remarkable risk of postoperative morbidity and mortality, the 5-year survival rate after radical surgery (R0) is 20-40% and recurrence rates are up to ~ 75%(4-6). Up to ~ 40% of patients relapse within 12 months after resection, and half of these patient will recur systemically(4-6). There is no standard of care for neoadjuvant chemotherapy (NAC) in resectable BTC, but retrospective reports suggest its potential benefit (7, 8). METHODS: PURITY is a no-profit, multicentre, randomized phase II/III trial aimed at evaluating the efficacy of the combination of gemcitabine, cisplatin and nabpaclitaxel (GAP) as neoadjuvant treatment in patients with resectable BTC at high risk for recurrence. Primary objective of this study is to evaluate the efficacy of neoadjuvant GAP followed by surgery as compared to upfront surgery, in terms of 12-month progression-free survival for the phase II part and of progression free survival (PFS) for the phase III study. Key Secondary objectives are event free survival (EFS), relapse-free survival, (RFS), overall survival (OS), R0/R1/R2 resection rate, quality of life (QoL), overall response rate (ORR), resectability. Safety analyses will include toxicity rate and perioperative morbidity and mortality rate. Exploratory studies including Next-Generation Sequencing (NGS) in archival tumor tissues and longitudinal ctDNA analysis are planned to identify potential biomarkers of primary resistance and prognosis. DISCUSSION: Considering the poor prognosis of resected BTC experiencing early tumor recurrence and the negative prognostic impact of R1/R2 resections, PURITY study is based on the rationale that NAC may improve R0 resection rates and ultimately patients' outcomes. Furthermore, NAC should allow early eradication of microscopic distant metastases, undetectable by imaging but already present at the time of diagnosis and avoid mortality and morbidity associated with resection for patients with rapid progression or worsening general condition during neoadjuvant therapy. The randomized PURITY study will evaluate whether patients affected by BTC at high risk from recurrence benefit from a neoadjuvant therapy with GAP regimen as compared to immediate surgery. TRIAL REGISTRATION: PURITY is registered at ClinicalTrials.gov (NCT06037980) and EuCT(2023-503295-25-00).

See Elegans: Simple-to-use, accurate, and automatic 3D detection of neural activity from densely packed neurons.

In the emerging field of whole-brain imaging at single-cell resolution, which represents one of the new frontiers to investigate the link between brain activity and behavior, the nematode Caenorhabditis elegans offers one of the most characterized models for systems neuroscience. Whole-brain recordings consist of 3D time series of volumes that need to be processed to obtain neuronal traces. Current solutions for this task are either computationally demanding or limited to specific acquisition setups. Here, we propose See Elegans, a direct programming algorithm that combines different techniques for automatic neuron segmentation and tracking without the need for the RFP channel, and we compare it with other available algorithms. While outperforming them in most cases, our solution offers a novel method to guide the identification of a subset of head neurons based on position and activity. The built-in interface allows the user to follow and manually curate each of the processing steps. See Elegans is thus a simple-to-use interface aimed at speeding up the post-processing of volumetric calcium imaging recordings while maintaining a high level of accuracy and low computational demands. (Contact: enrico.lanza@iit.it).

Modulating the skin mycobiome-bacteriome and treating seborrheic dermatitis with a probiotic-enriched oily suspension.

Seborrheic dermatitis (SD) affects 2-5% of the global population, with imbalances in the skin microbiome implicated in its development. This study assessed the impact of an oily suspension containing Lactobacillus crispatus P17631 and Lacticaseibacillus paracasei I1688 (termed EUTOPLAC) on SD symptoms and the skin mycobiome-bacteriome modulation. 25 SD patients were treated with EUTOPLAC for a week. Symptom severity and skin mycobiome-bacteriome changes were measured at the start of the treatment (T0), after seven days (T8), and three weeks post-treatment (T28). Results indicated symptom improvement post-EUTOPLAC, with notable reductions in the Malassezia genus. Concurrently, bacterial shifts were observed, including a decrease in Staphylococcus and an increase in Lactobacillus and Lacticaseibacillus. Network analysis highlighted post-EUTOPLAC instability in fungal and bacterial interactions, with increased negative correlations between Malassezia and Lactobacillus and Lacticaseibacillus genera. The study suggests EUTOPLAC's potential as a targeted SD treatment, reducing symptoms and modulating the mycobiome-bacteriome composition.

Bacterial Biofilm in Chronic Wounds and Possible Therapeutic Approaches.

Wound repair and skin regeneration is a very complex orchestrated process that is generally composed of four phases: hemostasis, inflammation, proliferation, and remodeling. Each phase involves the activation of different cells and the production of various cytokines, chemokines, and other inflammatory mediators affecting the immune response. The microbial skin composition plays an important role in wound healing. Indeed, skin commensals are essential in the maintenance of the epidermal barrier function, regulation of the host immune response, and protection from invading pathogenic microorganisms. Chronic wounds are common and are considered a major public health problem due to their difficult-to-treat features and their frequent association with challenging chronic infections. These infections can be very tough to manage due to the ability of some bacteria to produce multicellular structures encapsulated into a matrix called biofilms. The bacterial species contained in the biofilm are often different, as is their capability to influence the healing of chronic wounds. Biofilms are, in fact, often tolerant and resistant to antibiotics and antiseptics, leading to the failure of treatment. For these reasons, biofilms impede appropriate treatment and, consequently, prolong the wound healing period. Hence, there is an urgent necessity to deepen the knowledge of the pathophysiology of delayed wound healing and to develop more effective therapeutic approaches able to restore tissue damage. This work covers the wound-healing process and the pathogenesis of chronic wounds infected by biofilm-forming pathogens. An overview of the strategies to counteract biofilm formation or to destroy existing biofilms is also provided.

Hard-to-heal peripheral wounds infected with Corynebacterium striatum: a prospective study.

OBJECTIVE: To investigate Corynebacterium striatum as a nosocomial pathogen infecting hard-to-heal peripheral wounds, such as skin wounds, soft tissue abscesses and osteomyelitis. As of 2023, the medical community were alerted against the risk of emerging systemic and central infections; on the other hand literature on peripheral cutaneous regions is still scarce. METHOD: In this study, two groups of patients with similar lesions which were infected were compared: one group with the presence of the coryneform rod, the other without. RESULTS: In total, Corynebacterium striatum was cultured from 62 patients and 131 samples. Corynebacterium striatum infection correlated well with the presence of: foot ulcer; venous leg ulcer; altered ambulation and/or altered foot loading; peripheral vascular and arterial disease; hospitalisation; malignancy; spinal cord injury; and recent administration of antibiotics (p<0.05 for all associations). Patients with Corynebacterium striatum had a lower overall survival rate compared to patients in the non-Corynebacterium striatum group (28.6 versus 31.6 months, respectively; p=0.0285). Multivariate analysis revealed that Corynebacterium striatum infection was an independent factor for poor prognosis (p<0.0001). CONCLUSION: In view of the findings of our study, Corynebacterium striatum appears to be an important opportunistic pathogen infecting peripheral tissues and complicating wound healing. Given its numerous and worrying virulence factors (such as multidrug resistance and biofilm production), particular attention should be given to this pathogen by professional wound care providers in nosocomial and outpatient environments.

Acinetobacter baumannii in the critically ill: complex infections get complicated.

Acinetobacter baumannii is increasingly associated with various epidemics, representing a serious concern due to the broad level of antimicrobial resistance and clinical manifestations. During the last decades, A. baumannii has emerged as a major pathogen in vulnerable and critically ill patients. Bacteremia, pneumonia, urinary tract, and skin and soft tissue infections are the most common presentations of A. baumannii, with attributable mortality rates approaching 35%. Carbapenems have been considered the first choice to treat A. baumannii infections. However, due to the widespread prevalence of carbapenem-resistant A. baumannii (CRAB), colistin represents the main therapeutic option, while the role of the new siderophore cephalosporin cefiderocol still needs to be ascertained. Furthermore, high clinical failure rates have been reported for colistin monotherapy when used to treat CRAB infections. Thus, the most effective antibiotic combination remains disputed. In addition to its ability to develop antibiotic resistance, A. baumannii is also known to form biofilm on medical devices, including central venous catheters or endotracheal tubes. Thus, the worrisome spread of biofilm-producing strains in multidrug-resistant populations of A. baumannii poses a significant treatment challenge. This review provides an updated account of antimicrobial resistance patterns and biofilm-mediated tolerance in A. baumannii infections with a special focus on fragile and critically ill patients.

Skin dysbiosis and Cutibacterium acnes biofilm in inflammatory acne lesions of adolescents.

Acne vulgaris is a common inflammatory disorder affecting more than 80% of young adolescents. Cutibacterium acnes plays a role in the pathogenesis of acne lesions, although the mechanisms are poorly understood. The study aimed to explore the microbiome at different skin sites in adolescent acne and the role of biofilm production in promoting the growth and persistence of C. acnes isolates. Microbiota analysis showed a significantly lower alpha diversity in inflammatory lesions (LA) than in non-inflammatory (NI) lesions of acne patients and healthy subjects (HS). Differences at the species level were driven by the overabundance of C. acnes on LA than NI and HS. The phylotype IA1 was more represented in the skin of acne patients than in HS. Genes involved in lipids transport and metabolism, as well as potential virulence factors associated with host-tissue colonization, were detected in all IA1 strains independently from the site of isolation. Additionally, the IA1 isolates were more efficient in early adhesion and biomass production than other phylotypes showing a significant increase in antibiotic tolerance. Overall, our data indicate that the site-specific dysbiosis in LA and colonization by virulent and highly tolerant C. acnes phylotypes may contribute to acne development in a part of the population, despite the universal carriage of the microorganism. Moreover, new antimicrobial agents, specifically targeting biofilm-forming C. acnes, may represent potential treatments to modulate the skin microbiota in acne.

Green In Situ Synthesis of Silver Nanoparticles-Peptide Hydrogel Composites: Investigation of Their Antibacterial Activities.

The present paper investigated the synthesis of peptide-based hydrogel composites containing photo-generated silver nanoparticles (AgNPs) obtained in the presence and absence of honey as tensile strength enhancer and hydrogel stabilizer. Fmoc-Phe and diphenylalanine (Phe2) were used as starting reagents for the hydrogelator synthesis via an enzymatic method. In particular, we developed an in situ one-pot approach for preparing AgNPs inside peptide hydrogels using a photochemical synthesis, without any toxic reducing agents, with reaction yields up to 30%. The structure and morphology of the nanohybrids were characterized with different techniques such as FESEM, UV-Vis, DLS, SAXS and XPS. Moreover, the antibacterial activity of these hybrid biomaterials was investigated on a laboratory strain and on a clinical isolate of Staphylococcus aureus. Results demonstrated that honey increased both swelling ability and also mechanical stability of the hydrogel. Finally, a higher antibacterial effect of AgNPs in the hybrid was observed in the presence of honey. In particular, AgNPs/hgel and AgNPs/hgel-honey showed an enhanced antibacterial activity (3.12 mg/L) compared to the free form of AgNPs, alone or in combination with honey (6.25 mg/L) for both S. aureus strains.

Homocysteine and Inflammatory Cytokines in the Clinical Assessment of Infection in Venous Leg Ulcers.

Inflammation and biofilm-associated infection are common in chronic venous leg ulcers (VU), causing deep pain and delayed healing. Albeit important, clinical markers and laboratory parameters for identifying and monitoring persistent VU infections are limited. This study analyzed 101 patients with infected (IVU) and noninfected VUs (NVU). Clinical data were collected in both groups. The serum homocysteine (Hcys) and inflammatory cytokines from the wound fluid were measured. In addition, microbial identification, antibiotic susceptibility, and biofilm production were examined. IVU were 56 (55.4%) while NVU were 45 (44.5%). IVUs showed a significant increase in the wound's size and depth compared to NVUs. In addition, significantly higher levels of interleukin (IL)-6, IL-10, IL17A, and tumor necrosis factor-alpha (TNF-α) were found in patients with IVUs compared to those with NVUs. Notably, hyperhomocysteinemia (HHcy) was significantly more common in patients with IVUs than NVUs. A total of 89 different pathogens were identified from 56 IVUs. Gram-negative bacteria were 51.7%, while the Gram-positives were 48.3%. At the species level, Staphylococcus aureus was the most common isolate (43.8%), followed by Pseudomonas aeruginosa (18.0%). Multidrug-resistant organisms (MDROs) accounted for 25.8% of the total isolates. Strong biofilm producers (SBPs) (70.8%) were significantly more abundant than weak biofilm producers (WBP) (29.2%) in IVUs. SBPs were present in 97.7% of the IVUs as single or multispecies infections. Specifically, SBPs were 94.9% for S. aureus, 87.5% for P. aeruginosa, and 28.6% for Escherichia coli. In IVU, the tissue microenvironment and biofilm production can support chronic microbial persistence and a most severe clinical outcome even in the presence of an intense immune response, as shown by the high levels of inflammatory molecules. The measurement of local cytokines in combination with systemic homocysteine may offer a novel set of biomarkers for the clinical assessment of IVUs caused by biofilm-producing bacteria.

Role of Extracellular DNA in Dalbavancin Activity against Methicillin-Resistant Staphylococcus aureus (MRSA) Biofilms in Patients with Skin and Soft Tissue Infections.

Methicillin-resistant Staphylococcus aureus (MRSA) has become the leading cause of skin and soft tissue infections (SSTIs). Biofilm production further complicates patient treatment, contributing to increased bacterial persistence and antibiotic tolerance. The study aimed to explore the efficacy of different antibiotics on biofilm-producing MRSA isolated from patients with SSTI. A total of 32 MRSA strains were collected from patients with SSTI. The MIC and minimal biofilm eradication concentration (MBEC) were measured in planktonic and biofilm growth. The study showed that dalbavancin, linezolid, and vancomycin all inhibited MRSA growth at their EUCAST susceptible breakpoint. Of the MRSA strains, 87.5% (n = 28) were strong biofilm producers (SBPs), while only 12.5% (n = 4) were weak biofilm producers (WBPs). The MBEC90 values for dalbavancin were significantly lower than those of linezolid and vancomycin in all tested strains. We also found that extracellular DNA (eDNA) contributes to the initial microbial attachment and biofilm formation. The amount of eDNA differed among MRSA strains and was significantly higher in those isolates with high dalbavancin and vancomycin tolerance. Exogenously added DNA increased the MBEC90 and protection of biofilm cells from dalbavancin activity. Of note, the relative abundance of eDNA was higher in MRSA biofilms exposed to MBEC90 dalbavancin than in untreated MRSA biofilms and those exposed to sub-MIC90. Overall, dalbavancin was the most active antibiotic against MRSA biofilms at concentrations achievable in the human serum. Moreover, the evidence of a drug-related increase of eDNA and its contribution to antimicrobial drug tolerance reveals novel potential targets for antibiofilm strategies against MRSA. IMPORTANCE Staphylococcus aureus is the most common cause of skin and soft tissue infections (SSTIs) worldwide. In addition, methicillin-resistant S. aureus (MRSA) is increasingly frequent in postoperative infections and responsible for a large number of hospital readmissions and deaths. Biofilm formation by S. aureus is a primary risk factor in SSTIs, due to a higher antibiotic tolerance. Our study showed that the biofilm-forming capacity varied among MRSA strains, although strong biofilm producers were significantly more abundant than weak biofilm producer strains. Notably, dalbavancin demonstrated a potent antibiofilm activity at concentrations achievable in human serum. Nevertheless, dalbavancin activity was affected by an increased concentration of extracellular DNA in the biofilm matrix. This study provides novel insight for designing more targeted therapeutic strategies against MRSA and to prevent or eradicate harmful biofilms.

Evidence of a SARS-CoV-2 double Spike mutation D614G/S939F potentially affecting immune response of infected subjects.

OBJECTIVES: Despite extensive efforts to monitor the diffusion of COVID-19, the actual wave of infection is worldwide characterized by the presence of emerging SARS-CoV-2 variants. The present study aims to describe the presence of yet undiscovered SARS-CoV-2 variants in Italy. METHODS: Next Generation Sequencing was performed on 16 respiratory samples from occasionally employed within the Bangladeshi community present in Ostia and Fiumicino towns. Computational strategy was used to identify all potential epitopes for reference and mutated Spike proteins. A simulation of proteasome activity and the identification of possible cleavage sites along the protein guided to a combined score involving binding affinity, peptide stability and T-cell propensity. RESULTS: Retrospective sequencing analysis revealed a double Spike D614G/S939F mutation in COVID-19 positive subjects present in Ostia while D614G mutation was evidenced in those based in Fiumicino. Unlike D614G, S939F mutation affects immune response by the slight but significant modulation of T-cell propensity and the selective enrichment of potential binding epitopes for some HLA alleles. CONCLUSION: Collectively, our findings mirror further the importance of deep sequencing of SARS-CoV-2 genome as a unique approach to monitor the appearance of specific mutations as for those herein reported for Spike protein. This might have implications on both the type of immune response triggered by the viral infection and the severity of the related illness.

The Impact of Bacterial Biofilms on End-Organ Disease and Mortality in Patients with Hematologic Malignancies Developing a Bloodstream Infection.

Bacterial bloodstream infection (BSI) represents a significant complication in hematologic patients. However, factors leading to BSI and progression to end-organ disease and death are understood only partially. The study analyzes host and microbial risk factors and assesses their impact on BSI development and mortality. A total of 96 patients with hematological malignancies and BSI were included in the study. Host-associated risk factors and all causes of mortality were analyzed by multivariable logistic regression at 30 days after BSI onset of the first neutropenic episode. The multidrug-resistant profile and biofilm production of bacterial isolates from primary BSI were included in the analysis. Median age was 60 years. The underlying diagnoses were acute leukemia (55%), lymphoma (31%), and myeloma (14%). A total of 96 bacterial isolates were isolated from BSIs. Escherichia coli was the most common isolate (29.2%). Multidrug-resistant bacteria caused 10.4% of bacteremia episodes. Weak biofilm producers (WBPs) were significantly (P < 0.0001) more abundant (72.2%) than strong biofilm producers (SBPs) (27.8%). Specifically, SBPs were 7.1% for E. coli, 93.7% for P. aeruginosa, 50% for K. pneumoniae, and 3.8% for coagulase-negative staphylococci. Mortality at day 30 was 8.3%, and all deaths were attributable to Gram-negative bacteria. About 22% of all BSIs were catheter-related BSIs (CRBSIs) and mostly caused by Gram-positive bacteria (79.0%). However, CRBSIs were not correlated with biofilm production levels (P = 0.75) and did not significantly impact the mortality rate (P = 0.62). Conversely, SBP bacteria were an independent risk factor (P = 0.018) for developing an end-organ disease. In addition, multivariate analysis indicated that SBPs (P = 0.013) and multidrug-resistant bacteria (P = 0.006) were independent risk factors associated with 30-day mortality. SBP and multidrug-resistant (MDR) bacteria caused a limited fraction of BSI in these patients. However, when present, SBPs raise the risk of end-organ disease and, together with an MDR phenotype, can independently and significantly concur at increasing the risk of death. IMPORTANCE Bacterial bloodstream infection (BSI) is a significant complication in hematologic patients and is associated with high mortality rates. Despite improvements in BSI management, factors leading to sepsis are understood only partially. This study analyzes the contribution of bacterial biofilm on BSI development and mortality in patients with hematological malignancies (HMs). In this work, weak biofilm producers (WBPs) were significantly more abundant than strong biofilm producers (SBPs). However, when present, SBP bacteria raised the risk of end-organ disease in HM patients developing a BSI. Besides, SBPs, together with a multidrug-resistant (MDR) phenotype, independently and significantly concur at increasing the risk of death in HM patients. The characterization of microbial biofilms may provide key information for the diagnosis and therapeutic management of BSI and may help develop novel strategies to either eradicate or control harmful microbial biofilms.

Biofilm Production by Carbapenem-Resistant Klebsiella pneumoniae Significantly Increases the Risk of Death in Oncological Patients.

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a prominent cause of nosocomial infections associated with high rates of morbidity and mortality, particularly in oncological patients. The hypermucoviscous (HMV) phenotype and biofilm production are key factors for CRKP colonization and persistence in the host. This study aims at exploring the impact of CRKP virulence factors on morbidity and mortality in oncological patients. A total of 86 CRKP were collected between January 2015 and December 2019. Carbapenem resistance-associated genes, antibiotic susceptibility, the HMV phenotype, and biofilm production were evaluated. The median age of the patients was 71 years (range 40-96 years). Clinically infected patients were 53 (61.6%), while CRKP colonized individuals were 33 (38.4%). The most common infectious manifestations were sepsis (43.4%) and pneumonia (18.9%), while rectal surveillance swabs were the most common site of CRKP isolation (81.8%) in colonized patients. The leading mechanism of carbapenem resistance was sustained by the KPC gene (96.5%), followed by OXA-48 (2.3%) and VIM (1.2%). Phenotypic CRKP characterization indicated that 55.8% of the isolates were strong biofilm-producers equally distributed between infected (54.2%) and colonized (45.8%) patients. The HMV phenotype was found in 22.1% of the isolates, which showed a significant (P<0.0001) decrease in biofilm production as compared to non-HMV strains. The overall mortality rate calculated on the group of infected patients was 35.8%. In univariate analysis, pneumoniae significantly correlated with death (OR 5.09; CI 95% 1.08-24.02; P=0.04). The non-HMV phenotype (OR 4.67; CI 95% 1.13-19.24; P=0.03) and strong biofilm-producing strains (OR 5.04; CI95% 1.39-18.25; P=0.01) were also associated with increased CRKP infection-related mortality. Notably, the multivariate analysis showed that infection with strong biofilm-producing CRKP was an independent predictor of mortality (OR 6.30; CI 95% 1.392-18.248; P=0.004). CRKP infection presents a high risk of death among oncological patients, particularly when pneumoniae and sepsis are present. In infected patients, the presence of strong biofilm-producing CRKP significantly increases the risk of death. Thus, the assessment of biofilm production may provide a key element in supporting the clinical management of high-risk oncological patients with CRKP infection.

Silver Sulfadiazine Eradicates Antibiotic-Tolerant Staphylococcus aureus and Pseudomonas aeruginosa Biofilms in Patients with Infected Diabetic Foot Ulcers.

Infections are among the most frequent and challenging events in diabetic foot ulcers (DFUs). Pathogenic bacteria growing in biofilms within host tissue are highly tolerant to environmental and chemical agents, including antibiotics. The present study was aimed at assessing the use of silver sulfadiazine (SSD) for wound healing and infection control in 16 patients with DFUs harboring biofilm-growing Staphylococcus aureus and Pseudomonas aeruginosa. All patients received a treatment based on a dressing protocol including disinfection, cleansing, application of SSD, and application of nonadherent gauze, followed by sterile gauze and tibio-breech bandage, in preparation for toilet surgery after 30 days of treatment. Clinical parameters were analyzed by the T.I.M.E. classification system. In addition, the activity of SSD against biofilm-growing S. aureus and P. aeruginosa isolates was assessed in vitro. A total of 16 patients with S. aureus and P. aeruginosa infected DFUs were included in the study. Clinical data showed a statistically significant (p < 0.002) improvement of patients' DFUs after 30 days of treatment with SSD with significant amelioration of all the parameters analyzed. Notably, after 30 days of treatment, resolution of infection was observed in all DFUs. In vitro analysis showed that both S. aureus and P. aeruginosa isolates developed complex and highly structured biofilms. Antibiotic susceptibility profiles indicated that biofilm cultures were significantly (p ≤ 0.002) more tolerant to all tested antimicrobials than their planktonic counterparts. However, SSD was found to be effective against fully developed biofilms of both S. aureus and P. aeruginosa at concentrations below those normally used in clinical preparations (10 mg/mL). These results strongly suggest that the topical administration of SSD may represent an effective alternative to conventional antibiotics for the successful treatment of DFUs infected by biofilm-growing S. aureus and P. aeruginosa.

Microbial biofilm correlates with an increased antibiotic tolerance and poor therapeutic outcome in infective endocarditis.

BACKGROUND: Infective endocarditis (IE) is associated with high rates of mortality. Prolonged treatments with high-dose intravenous antibiotics often fail to eradicate the infection, frequently leading to high-risk surgical intervention. By providing a mechanism of antibiotic tolerance, which escapes conventional antibiotic susceptibility profiling, microbial biofilm represents a key diagnostic and therapeutic challenge for clinicians. This study aims at assessing a rapid biofilm identification assay and a targeted antimicrobial susceptibility profile of biofilm-growing bacteria in patients with IE, which were unresponsive to antibiotic therapy. RESULTS: Staphylococcus aureus was the most common isolate (50%), followed by Enterococcus faecalis (25%) and Streptococcus gallolyticus (25%). All microbial isolates were found to be capable of producing large, structured biofilms in vitro. As expected, antibiotic treatment either administered on the basis of antibiogram or chosen empirically among those considered first-line antibiotics for IE, including ceftriaxone, daptomycin, tigecycline and vancomycin, was not effective at eradicating biofilm-growing bacteria. Conversely, antimicrobial susceptibility profile of biofilm-growing bacteria indicated that teicoplanin, oxacillin and fusidic acid were most effective against S. aureus biofilm, while ampicillin was the most active against S. gallolyticus and E. faecalis biofilm, respectively. CONCLUSIONS: This study indicates that biofilm-producing bacteria, from surgically treated IE, display a high tolerance to antibiotics, which is undetected by conventional antibiograms. The rapid identification and antimicrobial tolerance profiling of biofilm-growing bacteria in IE can provide key information for both antimicrobial therapy and prevention strategies.

Staphylococcus aureus and the Cutaneous Microbiota Biofilms in the Pathogenesis of Atopic Dermatitis.

Biofilm is the dominant mode of growth of the skin microbiota, which promotes adhesion and persistence in the cutaneous microenvironment, thus contributing to the epidermal barrier function and local immune modulation. In turn, the local immune microenvironment plays a part in shaping the skin microbiota composition. Atopic dermatitis (AD) is an immune disorder characterized by a marked dysbiosis, with a sharp decline of microbial diversity. During AD flares biofilm-growing Staphylococcus aureus emerges as the major colonizer in the skin lesions, in strict association with disease severity. The chronic production of inflammatory cytokines in the skin of AD individuals concurs at supporting S. aureus biofilm overgrowth at the expense of other microbial commensals, subverting the composition of the healthy skin microbiome. The close relationship between the host and microbial biofilm resident in the skin has profound implications on human health, making skin microbiota an attractive target for the therapeutic management of different skin disorders.

Long-term performance of risk scores for venous thromboembolism in ambulatory cancer patients.

The long-term performance of prediction scores for venous thromboembolism (VTE) in cancer patients has been poorly investigated. We evaluated the discriminatory performance of the Khorana, PROTECHT, CONKO, and ONKOTEV scores for the first 3-6 months and for 12 months, and re-assessed scores after 3-6 months to determine the influence of variations in patients' risk classification on performance. Retrospective cohort of ambulatory patients with active cancer who were scheduled to receive first or new line of chemotherapy. The primary outcome was symptomatic or incidental VTE. A total of 776 patients were included of whom 540 (70%) had distant metastases. The time-dependent c-statistics of Khorana, PROTECHT, CONKO, and ONKOTEV scores at 6 months were 0.61 (95% CI 0.56 to 0.66), 0.61 (95% CI 0.55 to 0.66), 0.60 (95% CI 0.54 to 0.66), and 0.59 (0.52 to 0.66), respectively, with a tendency to decrease during follow-up. None of the scores discriminated between high and low risk patients at the conventional 3-point positivity threshold. The use of a 2-point positivity threshold improved performance of all scores and captured a higher proportion of VTE. The accuracy of risk scores re-assessed at 3-6 months was modest. The Khorana, PROTECHT, CONKO, and ONKOTEV scores are not sufficiently accurate when used at a conventional threshold of 3 points. Performance improves at positivity threshold of 2 points, as evaluated in recent randomized studies on VTE prophylaxis. Score accuracy tends to decrease over time suggesting the need of periodic re-evaluation to estimate possible variation of risk.

[Turn-over of non-tenured public health research personnel in an Italian public research institute (IRCCS).] / Il turn-over del personale con contratti di lavoro flessibili o borse di studio dedicato alla ricerca sanitaria in un IRCCS pubblico italiano.

BACKGROUND: The objective is to show variations in the number of non-tenured personnel (NTP) in a public health research centre (IRCCS) between 30th June 2016 and 31st December 2017. In this time interval, the issue of NTP was at the centre of governmental discussions. METHODS: Data collection was performed from CVs and scientific publications of NTP working at the Fondazione IRCCS Istituto Nazionale dei Tumori (INT). We compared the characteristics of NTP entering or leaving INT and those of NTP who remained in the considered time interval. RESULTS: NTP in INT counted 465 members of staff at 30th June 2016 and 472 at 31st December 2017. 75% of these works in the research. 26% of NTP left INT and their position resulted entirely substituted by other NTP. NTP staff who left are mainly aged under 40 and show fewer publications than those who stayed. Newly acquired NTP are younger and show a fewer number of publications compared to the personnel who left. CONCLUSIONS: 1 out of 4 NTP members of staff moved to a new job during a period in which the uncertain future of NTP research staff was under the spotlight. It appears that IRCCS are progressively being identified as suitable for hands-on, post university internships from which researchers would then choose to move, in search of a new job in public or private centres, with a consequent decline of IRCCS' role in health research.