Immunoregulatory Effects of Mesenchymal Stem Cell-Derived Extracellular Vesicles on T Lymphocytes.

The immunomodulatory activity of mesenchymal stem cells (MSCs) is largely mediated by paracrine factors. We have recently shown that the immunosuppressive effects of MSCs on B lymphocytes in peripheral blood mononuclear cell (PBMC) culture can be reproduced by extracellular vesicles (EVs) isolated from MSC culture supernatants. Here we investigated the effect of bone marrow-derived MSC-EVs on T cells on PBMC cultures stimulated with anti-CD3/CD28 beads. Stimulation increased the number of proliferating CD3+ cells as well as of regulatory T cells (Tregs). Coculture with MSCs inhibited the proliferation of CD3+ cells, with no significant changes in apoptosis. Addition of MSC-EVs to PBMCs did not affect proliferation of CD3+ cells, but induced the apoptosis of CD3+ cells and of the CD4+ subpopulation and increased the proliferation and the apoptosis of Tregs. Moreover, MSC-EV treatment increased the Treg/Teff ratio and the immunosuppressive cytokine IL-10 concentration in culture medium. The activity of indoleamine 2,3-dioxygenase (IDO), an established mediator of MSC immunosuppressive effects, was increased in supernatants of PBMCs cocultured with MSCs, but was not affected by the presence of MSC-EVs. MSC-EVs demonstrate immunomodulatory effects on T cells in vitro. However, these effects and the underlying mechanisms appear to be different from those exhibited by their cells of origin

A MALDI-TOF MS approach for mammalian, human, and formula milks’ profiling

Human milk composition is dynamic, and substitute formulae are intended to mimic its protein content. The purpose of this study was to investigate the potentiality of matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS), followed by multivariate data analyses as a tool to analyze the peptide profiles of mammalian, human, and formula milks. Breast milk samples from women at different lactation stages (2 (n = 5), 30 (n = 6), 60 (n = 5), and 90 (n = 4) days postpartum), and milk from donkeys (n = 4), cows (n = 4), buffaloes (n = 7), goats (n = 4), ewes (n = 5), and camels (n = 2) were collected. Different brands (n = 4) of infant formulae were also analyzed. Protein content (<30 kDa) was analyzed by MS, and data were exported for statistical elaborations. The mass spectra for each milk closely clustered together, whereas different milk samples resulted in well-separated mass spectra. Human samples formed a cluster in which colostrum constituted a well-defined subcluster. None of the milk formulae correlated with animal or human milk, although they were specifically characterized and correlated well with each other. These findings propose MALDI-TOF MS milk profiling as an analytical tool to discriminate, in a blinded way, different milk types. As each formula has a distinct specificity, shifting a baby from one to another formula implies a specific proteomic exposure. These profiles may assist in milk proteomics for easiness of use and minimization of costs, suggesting that the MALDI-TOF MS pipelines may be useful for not only milk adulteration assessments but also for the characterization of banked milk specimens in pediatric clinical settings

Microbial air monitoring in the operating theatres of Salam Center for Cardiac Surgery in Khartoum (Sudan)

The seriousness of postoperative infections and the increased susceptibility of patients undergoing cardiac surgery increase the demand for the operating theatre (OT) asepsis to prevent bacterial infections. In fact, the organisms carried by the air reach the wound after having sedimented onto sterile field. The air represents a critical point for quality control of air filtration systems, for sanitization procedures and for the evolution of hygienic features of the OT environment.Aim of the study is to evaluate the prevalence of microorganisms found in the operating rooms (OR) air monitoring in the Salam Center for Cardiac Surgery of Khartoum (Sudan) between July 2008 and March 2009.The specimens were collected every month in two different times: “OR at rest” (after sanitization) and “OR operational”, using sedimentation method (Fisher 1972). Results showed that each sample collected at rest had IMA (index of microbial air contamination) < 5CFU/plt, whereas the bacterial growth was between 25 and 50 CFU/plt when the samples had been collected in the same places during operating activities.This indicate the effectiveness of sanitization procedures and confirm that people working in OT are an important source of bacteria causing postoperative infections. Coagulase negative Staphylococci, Gram negative bacillus and Staphylococcus aureus spp. were the predominant organisms isolated

Epidemiology of pathogens isolated from blood cultures processed at the “Salam Center for Cardiac Surgery” in Khartoum (Sudan)

Introduction. Sepsis is a systemic inflammatory response to infection and it is a common cause of morbidity and mortality particularly in elderly, immunocompromised and critically ill patients. Blood culture represents the gold standard for bacteraemia diagnosis. Aim of our study was to assess Gram positive and Gram negative microorganisms isolated from bloodcultures collected from patients hospitalized in “Salam Center for Cardiac Surgery” of Khartoum (Sudan). Methods. The study was conduced from april 2008 and march 2009. In this period we analyzed 328 samples collected from hospitalized patients already operated or waiting for surgery, presenting fever of unknown origin (temperature >38°C). We analyzed at least 3 bloodcultures for each patient, which were incubated at 37°C for 8-10 days. During the incubation period the bottles were periodically examined for macroscopic evidence of growth and the laboratory staff performed blind subcultures after 48 h one from each other starting from the inoculation time. The isolated bacteria were finally tested for antibiotics sensitivity. Results. Of 328 bloodcultures processed 57 were positive (17.4%), of whom 40.3% caused by gram positive microorganisms and 59.7% by gram negative. The identification tests showed that among gram positive-related infections those caused by MRSA (Methicillin Resistant Staphylococcus aureus) predominated (65.2%), while the most prevalent causative agents among gram negative-related infections were Enterobacter spp. (20.6%), Serratia spp. (14.7%), Pseudomonas spp (8.8%) and Escherichia coli (8.8%). Conclusion. In this study we observed that the most frequent isolates were MRSA, whereas no infection caused by CNS (Coagulase-negative Staphylococci) was revealed. Susceptibility tests showed presence of presumptive extended-spectrum ß-lactamases (ESBLs) in Enterobacteriaceae and that aminoglycosides were the most effective antibiotics against both Gram positive and Gram negative bacteria. The infection process interested patients already operated more than patients waiting for surgery

Epidemiology of extended spectrum β-lactamase, AmpC and class A carbapenemases-producing organisms isolated at San Camillo Hospital of Treviso (Italy) between April 2012 and March 2014

The indiscriminate use of broad-spectrum cephalosporins of the last years has favoured the selection of extended spectrum β-lactamases (ESBLs), AmpC and class A carbapenemases (KPC)-producing Enterobacteriaceae strains, representing a real health emergency. At San Camillo Hospital of Treviso, Italy, between April 2012 and March 2014, we isolated 263 suspected ESBL-producing strains from various specimens, including urine (76.4%), wound swabs (9.9%), blood cultures (4.6%), vaginal swabs (2.7%), fragments of bone (1.5%) and other materials (4.9%). The majority of the isolated bacteria were represented by Escherichia coli (43.3%), followed by Klebsiella pneumoniae (34.2%), Proteus mirabilis (15.2%), Enterobacter spp. (3.8%), Morganella morganii (1.1%), Serratia spp. (0.8%), Proteus vulgaris (0.4%), Citrobacter freudii (0.4%), Providencia spp. (0.4%) and Pseudomonas aeruginosa (0.4%). Using confirmatory phenotypic tests, 89.4% of the isolated resulted ESBL producer, 15.3% of which were also AmpC-producers, 1.5% were ESBL negative and AmpC positive, 4.2% were ESBL negative and AmpC negative, and 4.9%, consisting solely of K.pneumoniae, were confirmed as KPC positive. ESBL-mediated resistance to cephalosporin is not always clearly evident using susceptibility testing performed by agar diffusion-disc or dilution methods, for this reason it is strictly recommended to use specific tests able to reveal important mechanisms of resistance. The optimal use of diagnostic tools in microbiology is necessary to fight the spreading of pathogens with multiple antibiotic resistance mechanisms and in order to avoid giving useless antibiotic therapies to the patients

CVC related infections reported from Salam Center for Cardiac Surgery of Khartoum

Introduction: Central venous catheter (CVC) plays an essential part in clinical management of patients admitted in Intensive Care Unit (ICU), even though catheterization is an invasive procedure that may facilitate bacterial migration from the skin surrounding the catheter insertion site to the catheter tip, representing a risk factor for the arise of bacteraemia and sepsis. Aim of our study was to assess the prevalence of micro-organisms found as responsibles of CVC-related infections and check their correspondence with those found in blood cultures collected from the same patients. Methods: The study was conduced from April 2008 to March 2009. In this period were analysed 29 CVC samples sent from ICU to the laboratory of the Salam Center for Cardiac Surgery of Khartoum (Sudan). CVC was removed after pericatheter skin disinfection and its tip was cut, put in a sterile container and finally sent to the laboratory, where it was immersed in Brain Heart Infusion (BHI) and incubated at 37°C.A first culture of the sample on Blood Agar plate was done after an incubation period of 1 hour, the second one after 24 hours. In case of bacterial growth were practiced identification and sensitivity test of the isolated bacteria. Results: Of the 29 analysed samples 38% showed bacterial growth of which 27% caused by gram positive and 73% by gram negative bacteria. The identification tests showed also that among gram positive-related infection predominated those caused by Methicillin-Resistent Staphylococcus aureus (MRSA) (67%), while among the gram negative infections predominated those caused by Pseudomonas spp (57%), followed by Enterobacter spp and Serratia spp. Conclusion: All the above mentioned infections were confirmed by examination of blood cultures collected simultaneously from the same patients. Furthermore the study showed that 73% of infections affected post-operative patients rather than those waiting for surgery

Prevalence and antimicrobial susceptibility of genital Mycoplasmas detected by Mycoplasma IST 2 from urogenital samples in Padua, Italy, between January 2014 and December 2015

Background and aims. The aim of this study is to define the epidemiology and the antimicrobial resistance profile of Ureaplasma spp. and Mycoplasma hominis isolated from urogenital specimens of patients attending the Microbiology and Virology Unit of Padua between January 2014 and December 2015. Materials and methods. The analysis was carried out on a total of 10861 samples. Species identification and antimicrobial susceptibility tests were performed using bioMérieux Mycoplasma IST 2. Results. 2668 samples (24.6%) from 2043 patients were positive: 2466 samples positive for Ureaplasma spp. (1897 patients) and 8 samples positive for M. hominis (8 patients), while in 194 samples (138 patients) was detected a coinfection. As for antimicrobial susceptibility of Ureaplasma spp. we found a resistance (R+I) rate of 90.6% for ciprofloxacin, of 74,1% for ofloxacin, of 52.8% for azithromycin and of 47.0% for erythromycin.Conclusions. Our report shows a high prevalence of Ureaplasma spp. in the study population. Surveillance of antibiotic resistance is critical for an appropriate therapeutic approach, which must always be contextualized with patient’s symptomatology

A simple and effective mass spectrometric approach to identify the adulteration of the mediterranean diet component extra-virgin olive oil with corn oil

Extra virgin olive oil (EVOO) with its nutraceutical characteristics substantially contributes as a major nutrient to the health benefit of the Mediterranean diet. Unfortunately, the adulteration of EVOO with less expensive oils (e.g., peanut and corn oils), has become one of the biggest source of agricultural fraud in the European Union, with important health implications for consumers, mainly due to the introduction of seed oil-derived allergens causing, especially in children, severe food allergy phenomena. In this regard, revealing adulterations of EVOO is of fundamental importance for health care and prevention reasons, especially in children. To this aim, effective analytical methods to assess EVOO purity are necessary. Here, we propose a simple, rapid, robust and very sensitive method for non-specialized mass spectrometric laboratory, based on the matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS) coupled to unsupervised hierarchical clustering (UHC), principal component (PCA) and Pearson’s correlation analyses, to reveal corn oil (CO) adulterations in EVOO at very low levels (down to 0.5%)