Acidity of SiO2-Supported Metal Oxides in the Presence of H2O Using the Adsorption Equilibrium Infrared Spectroscopy Method: 1. Adsorption and Coadsorption of NH3 and H2O on SiO2.

The present study is dedicated to the characterization (identification, heats of adsorption, and coverages) of the adsorbed species formed by the adsorption and coadsorption of NH3 and H2O on two SiO2 solids. Adsorption equilibrium infrared spectroscopy allowed us (a) to show that NH3 and H2O are mostly adsorbed on free SiOH groups via H bonds and (b) to determine their individual heats of adsorption: 53 and 49 kJ/mol, whatever be their coverages (Langmuir adsorption model), for NH3ads and H2Oads, respectively. These values consistent with the microcalorimetry literature data explain that their coverages are decreased upon NH3-H2O coadsorption, considering a competitive Langmuir model. However, the temperature-programmed adsorption equilibrium procedure achieved from MS data indicated that a minor amount of other NH3 species (not detected using Fourier-transform infrared) is more strongly adsorbed and that hydrolysis of SiOSi siloxane by H2O could occur in parallel. NH3-H2O coadsorption leads to the formation of NH4+ species, which involves H2O adsorbed species. Both NH3 and H2O are not adsorbed above 450 K, which means that the SiO2 contribution to the characterization of the acidity of metal oxide catalysts supported on SiO2 using NH3 as the probe molecule in the presence of H2O is negligible above this temperature.

Acidity of SiO2-Supported Metal Oxides in the Presence of H2O Using the AEIR Method: 2. Adsorption and Coadsorption of NH3 and H2O on TiO2/SiO2 Catalysts.

Two different TiO2/SiO2 compounds containing TiO2 nanodomains dispersed over SiO2 were investigated applying the AEIR method at the adsorption equilibrium of NH3 and H2O from 300 to 723 K, particularly for the measurement of the individual heats of adsorption of the different species on Lewis acidic sites (LAS) and Brønsted acidic sites (BAS) as evaluation of the strength of the sites. It revealed two types of NH3 adsorption sites: the first ones could correspond either to NH3 species H-bonded to free OH groups or to coordinated weak LAS (named L1). The second ones (L2) were attributed to strongest LAS similar to those present at the surface of TiO2 nanocrystallites. They also correspond to the stronger adsorption sites of H2O. Two types of Brønsted acid sites (BAS) were additionally evidenced by the AEIR method and proposed to be specifically located on the Si-O-Ti bridging bonds at the TiO2/SiO2 interface. The heats of adsorption of the different adsorbed species provided by the AEIR method were consistent with literature data on average values of the heats of adsorption of NH3 and H2O from microcalorimetry measurements. The surface acidity of the two compounds in the presence of H2O was determined using NH3-H2O coadsorption. At T ≥ 473 K, the NH3 species on the L2 sites were not significantly displaced from the surface whatever the partial pressure of H2O studied in agreement with the Temkin competitive model using the individual heats of adsorption of the NH3 and H2O species. This model also revealed the presence of a small amount of H2O species adsorbed on L2 sites allowing H2O dissociation or/and hydrolysis of SiOTi or TiOTi bridges, leading to the formation of a much higher amount of BAS. Therefore, this original work combining the AEIR method and the Temkin competitive model provided new insights for understanding water effects on acidic oxide catalysts.

Intravescical prostatic protrusion is a predictor of alpha blockers response: results from an observational study.

BACKGROUND: To investigate the efficacy of tamsulosin in patients with lower urinary tract symptoms (LUTS) and benign prostatic enlargement (BPE) with intravesical prostatic protrusion (IPP). Ultrasound measurement of the IPP has been previously described as an effective instrument for the evaluation of benign prostatic obstruction (BPO) and could help in clarifying the role of alpha-blockers in patients with (BPE). METHODS: Patients with BPE and LUTS were enrolled in this observational study. Intravesical prostatic protrusion was graded as grade 1 (< 5 ml), 2 (5 < IPP < 10 ml) and 3 (> 10 ml). Patients were treated with tamsulosin for twelve weeks. Evaluation was performed before and at the end of treatment by means of International Prostate Symptom Score (IPSS) and uroflowmetry. Patients were considered responders if a reduction of IPSS > 3 points was reported. RESULTS: One hundred forty-two patients were enrolled. Twelve patients were excluded because of incomplete data. Fifty patients showed an IPP grade 1 (group A), 52 a grade 2 (group B) and 28 a grade 3 (group C). Treatment success was obtained in 82%, 38,5% and 7,1% of patients respectively; these differences (group A vs B-C and group B vs C) were highly significant. The odd ratio to obtain a treatment success was of 59 and 8.1 in group A and group B respectively, in comparison to group C. After a multivariate regression, the relationship between IPP grade and treatment success remained significant. Improvement of uroflowmetry parameters has been reported in all the groups especially in patients with a low grade IPP (p value = 0,016 group A vs group B; p value = 0,005 group A vs group C). Prostate volume seems not to influence this relationship. CONCLUSIONS: Intravesical prostatic protrusion has found to be significantly and inversely correlated with treatment success in patients with LUTS and BPE under alpha-blockers therapy. Alpha blockers odd ratio of success is 59 times higher in patients with a low grade IPP in comparison to patients with a high grade.

Behavior of Escherichia coli O157:H7 during the manufacture and ripening of Fontina Protected Designation of Origin cheese.

This study was conducted to describe the cheese-making procedure of Fontina Protected Designation of Origin (PDO) cheese and to evaluate the behavior of Escherichia coli O157:H7 during cheese manufacture and ripening. The study was divided into 2 phases: the production of Fontina PDO cheese was monitored at 3 different dairies in the Aosta Valley and an E. coli O157 challenge was conducted at a fourth dairy. The dairies employ different commercial starter cultures for cheese making. The growth of lactic acid bacilli (LAB) and the decrease in pH were slower in the first hours and the LAB concentrations were overall higher in dairy A than in the other 2 dairies. The pH remained substantially unchanged during ripening (range 5.2 to 5.4) in all dairies. Water activity remained constant at around 0.98 until d 21, when it decreased to around 0.97 until d 80 in dairies A and B and 0.95 in dairy E. Whole raw cow milk was used for making Fontina cheese according to the standard procedure. For the experimental production, the milk was inoculated with E. coli O157:H7 at a concentration of approximately 5 log10 cfu/mL and commercial starter cultures were used according to the Fontina PDO regulation. An increase of 2.0 log10 cfu/g in E. coli O157:H7 was observed during the first 9.5 h of cheese making, followed by a decrease at 46 h when pH decreased to 5.4 in all trials. Fresh cheeses were salted and held at 10°C for ripening for 80 d. Water activity was decreased to 0.952 at the end of the ripening stage. The LAB concentrations declined gradually; this trend was more marked for the lactobacilli than either the thermophilic or the mesophilic lactococci. The increase in LAB count and the decrease in pH in the first hours did not seem to affect E. coli O157 growth. Ripening was found to inhibit pathogen survival, however, as seen in the reduction of 3 log10 from the maximum concentration measured during the earlier stages of production.

Confined placental mosaicism for 22q11.2 deletion as the etiology for discordant positive NIPT results.

22q11.2 deletion, the most common microdeletion syndrome within the general population, is estimated to have a prevalence of 1 in 3000 to 6000. Non-invasive prenatal testing has recently expanded to include screening for several microdeletions including 22q11.2. Given the expansion of prenatal screening options to include microdeletions, it is important to understand the limits of this technology and the variety of reasons that a discordant positive result can occur. Here, we describe a case of a pregnant woman who received a positive non-invasive prenatal maternal plasma screen for 22q11.2 deletion. Maternal and postnatal neonatal peripheral blood cytogenetic, PCR, and fluorescence in situ hybridization studies were normal, but the placenta was mosaic for 22q11.2 deletion in two of three biopsy sites. This case illustrates both the complexities of pre- and post-test counseling for microdeletion screening and the potential for a discordant positive microdeletion result because of confined placental mosaicism. © 2017 John Wiley & Sons, Ltd.

Assessing the fetal effects of maternal obesity via transcriptomic analysis of cord blood: a prospective case-control study.

OBJECTIVE: To analyse fetal gene expression at term using umbilical cord blood, in order to provide insights into the effects of maternal obesity on human development. DESIGN: Prospective case-control study. SETTING: Academic tertiary care centre. POPULATION: Eight obese (body mass index ≥30 kg/m(2)) and eight lean (body mass index <25 kg/m(2)) pregnant women undergoing prelabour caesarean delivery at term. METHODS: Women were matched for gestational age and fetal sex. Cord blood RNA was extracted and hybridised to gene expression arrays. Differentially regulated genes were identified using paired t-tests and the Benjamini-Hochberg correction. Functional analyses were performed using Ingenuity Pathway Analysis, BioGPS and Gene Set Enrichment Analysis with a fetal-specific annotation. Z-scores ≥2.0 or P-values <0.01 were considered significant. MAIN OUTCOME MEASURE: Functions of differentially regulated genes in fetuses of obese women. RESULTS: A total of 701 differentially regulated genes were identified, producing an expression profile implicating neurodegeneration, decreased survival of sensory neurons, and decreased neurogenesis in the fetuses of obese women. Upstream regulators related to inflammatory signalling were significantly activated; those related to insulin receptor signalling, lipid homeostasis, regulation of axonal guidance, and cellular response to oxidative stress were significantly inhibited. Of 26 tissue-specific genes that were differentially regulated in fetuses of obese women, six mapped to the fetal brain. CONCLUSION: Maternal obesity affects fetal gene expression at term, implicating dysregulated brain development, inflammatory and immune signalling, glucose and lipid homeostasis, and oxidative stress. This may have implications for postnatal neurodevelopment and metabolism.

Applicability of Macroscopic Wear and Friction Laws on the Atomic Length Scale.

Using molecular dynamics, we simulate the abrasion process of an atomically rough Fe surface with multiple hard abrasive particles. By quantifying the nanoscopic wear depth in a time-resolved fashion, we show that Barwell's macroscopic wear law can be applied at the atomic scale. We find that in this multiasperity contact system, the Bowden-Tabor term, which describes the friction force as a function of the real nanoscopic contact area, can predict the kinetic friction even when wear is involved. From this the Derjaguin-Amontons-Coulomb friction law can be recovered, since we observe a linear dependence of the contact area on the applied load in accordance with Greenwood-Williamson contact mechanics.

Methicillin resistance in Staphylococcus aureus strains isolated from food and wild animal carcasses in Italy.

Following the detection of methicillin-resistant Staphylococcus aureus (MRSA) ST398 in food-producing animals, both livestock and wildlife, and derived products, are considered potential sources of MRSA in humans. There is a paucity of data on MRSA in foods in Italy, and the data regarding wild animals are particularly scarce. A total of 2162 food samples collected during official monitoring activities in 2008 were analyzed for the detection of S. aureus. Also, samples from 1365 wild animals collected by the National Reference Center for Wild Animal Diseases in 2003-2009 were subjected to anatomopathological examination. S. aureus isolates were processed for phenotypic and molecular methicillin resistance determinations. S. aureus was found in 2.0% of wild animal carcasses and in 3.2% of wild boar lymph nodes: none showed methicillin resistance. The prevalence of S. aureus in food was 17.1%. Two MRSA strains, both from bulk tank milk (prevalence 0.77%) were isolated: the strains were resistant to tetracycline, had spa-type t899, and were negative for the Panton-Valentine leukocidin gene. The low prevalence of MRSA suggests that the risk of transmission to humans via food is limited. However, attention should be paid to the cattle food chain, which may be a potential route of transmission of LA-MRSA.

Enterotoxin gene profiles of Staphylococcus aureus isolated from milk and dairy products in Italy.

UNLABELLED: Staphylococcal foodborne intoxication, occurring after consumption of staphylococcal enterotoxins (SEs) in food, is considered one of the most common forms of bacterial foodborne outbreaks worldwide. Milk and dairy products account for 5% of all the incriminated foods in staphylococcal outbreaks, referring to Europe. The distribution of genes encoding for enterotoxins in Staphylococcus aureus strains is highly variable, with some carried on stable regions of the chromosome and others carried on mobile genetic elements. The aim of this study was to analyse the distribution of genes encoding for SEs in Staph. aureus strains isolated from milk and dairy products. In the period from January 2010 to June 2011, a total of 1245 dairy samples (848 of raw milk and 397 of dairy products) were collected and analysed for detection of genes encoding for 11 SEs and SEls (SEA, SEB, SEC, SED, SEE, SEG, SEH, SEI, SER SElJ and SElP) according to the procedures of the Italian National Reference Laboratory for coagulase-positive Staphylococci including Staph. aureus. Staphylococcus aureus strains were isolated in 481 (39%) samples. Of the 481 isolates of Staph. aureus tested, 255 (53%) were positive for one or more SE genes, and thirty-five different enterotoxin gene profiles were distinguished among the isolates. ser gene, found in 134 (28%) of the isolates, was the most frequent, followed by sed (25%) and selj genes (25%). The identification of new SEs increased the isolation frequency of enterotoxigenic staphylococci, thus suggesting that the pathogenic potential of Staph. aureus may be of greater importance than previously thought. Further studies are needed to quantify the expression of these new enterotoxins, and to assess their contribution to foodborne disease burden. SIGNIFICANCE AND IMPACT OF THE STUDY: The analyses targeted 11 staphylococcal enterotoxins genes and 35 different enterotoxin gene profiles were distinguished among the isolates. A total of 255 Staph. aureus isolates were positive for one or more SE genes while ser gene was the most prevalent. In 93% of the isolates bearing genes located on the enterotoxin gene cluster (n = 89), both seg and sei genes were present.

Advantages and drawbacks of different methods to measure marginal gaps in fixed dental prostheses: A scoping review.

OBJECTIVES: This review aimed to compare traditional and digital methods to assess marginal gaps in fixed dental prostheses. Each method's characteristics, advantages, and limitations were identified and discussed, also addressing the knowledge gaps in the current scientific literature. DATA: Studies comparing currently available techniques for marginal gap examination were investigated. The main techniques analyzed were the Cross-Sectional Method (CSM), Direct View (DV), Silicone Replica Technique (SRT), Dual-Scan Method (DSM), Triple-Scan Method (TSM), Optical Coherence Tomography (OCT), and Micro-Computed Tomography (MCT). SOURCES: Two experienced independent reviewers screened online databases (MEDLINE via PubMed and Scopus) to identify studies published in English up to March 2024. References from primary studies and the main peer-reviewed scientific journals were manually searched. STUDY SELECTION: From an initial pool of 8126 articles, the reviewers meticulously selected 25 in vitro studies on objective comparisons between two or more methods for assessing marginal gaps in fixed dental prostheses on natural teeth. Publications that assessed marginal gaps in implant-supported fixed dental prostheses were excluded. CONCLUSIONS: This study highlights that while traditional methods like CSM and SRT are widely used and validated, they have limitations in comprehensive gap assessment, often neglecting recommended measurement points. The DV technique, focusing solely on external gaps, may be less relevant for modern assessments. Conversely, three-dimensional techniques like TSM, DSM, OCT, and MCT offer a more thorough evaluation of dental restoration fit. Moreover, digital methods such as TSM and DSM have a significant potential for future clinical application. CLINICAL SIGNIFICANCE: This review examined methods for evaluating marginal gaps in fixed dental prostheses. The review aids dental professionals and researchers in choosing the most suitable technique for clinical in vivo or laboratory assessment of the marginal adaptation of dental restorations. This study also indicates the need for an established and standardized assessment protocol for the marginal fit.

Mutations in RAB27A cause Griscelli syndrome associated with haemophagocytic syndrome.

Griscelli syndrome (GS, MIM 214450), a rare, autosomal recessive disorder, results in pigmentary dilution of the skin and the hair, the presence of large clumps of pigment in hair shafts and an accumulation of melanosomes in melanocytes. Most patients also develop an uncontrolled T-lymphocyte and macrophage activation syndrome (known as haemophagocytic syndrome, HS), leading to death in the absence of bone-marrow transplantation. In contrast, early in life some GS patients show a severe neurological impairment without apparent immune abnormalities. We previously mapped the GS locus to chromosome 15q21 and found a mutation in a gene (MYO5A) encoding a molecular motor in two patients. Further linkage analysis suggested a second gene associated with GS was in the same chromosomal region. Homozygosity mapping in additional families narrowed the candidate region to a 3.1-cM interval between D15S1003 and D15S962. We detected mutations in RAB27A, which lies within this interval, in 16 patients with GS. Unlike MYO5A, the GTP-binding protein RAB27A appears to be involved in the control of the immune system, as all patients with RAB27A mutations, but none with the MYO5A mutation, developed HS. In addition, RAB27A-deficient T cells exhibited reduced cytotoxicity and cytolytic granule exocytosis, whereas MYO5A-defective T cells did not. RAB27A appears to be a key effector of cytotoxic granule exocytosis, a pathway essential for immune homeostasis.

Investigation on a focus of human trichinellosis revealed by an atypical clinical case: after wild-boar (Sus scrofa) pork consumption in northern Italy.

Trichinellosis is one of the most serious foodborne parasitic zoonoses in Europe. Wild carnivorous and omnivorous hosts are the main reservoirs of Trichinella spp. nematodes in nature. In the winter of 2008-2009, an atypical clinical case of trichinellosis occurred for the consumption of pork from a wild boar (Sus scrofa) hunted in southwestern Alps in Italy. The symptomatic individual showed delayed development of oedemas in the lower limbs and eosinophilia, which appeared three months after infection. Muscle samples harboured 3.8 larvae/g, which were identified as Trichinella britovi. During the epidemiological investigation, anti-Trichinella IgG were detected in five hunters.

Clinical spectrum of SIX3-associated mutations in holoprosencephaly: correlation between genotype, phenotype and function.

BACKGROUND: Holoprosencephaly (HPE) is the most common structural malformation of the human forebrain. There are several important HPE mutational target genes, including the transcription factor SIX3, which encodes an early regulator of Shh, Wnt, Bmp and Nodal signalling expressed in the developing forebrain and eyes of all vertebrates. OBJECTIVE: To characterise genetic and clinical findings in patients with SIX3 mutations. METHODS: Patients with HPE and their family members were tested for mutations in HPE-associated genes and the genetic and clinical findings, including those for additional cases found in the literature, were analysed. The results were correlated with a mutation-specific functional assay in zebrafish. RESULTS: In a cohort of patients (n = 800) with HPE, SIX3 mutations were found in 4.7% of probands and additional cases were found through testing of relatives. In total, 138 cases of HPE were identified, 59 of whom had not previously been clinically presented. Mutations in SIX3 result in more severe HPE than in other cases of non-chromosomal, non-syndromic HPE. An over-representation of severe HPE was found in patients whose mutations confer greater loss of function, as measured by the functional zebrafish assay. The gender ratio in this combined set of patients was 1.5:1 (F:M) and maternal inheritance was almost twice as common as paternal. About 14% of SIX3 mutations in probands occur de novo. There is a wide intrafamilial clinical range of features and classical penetrance is estimated to be at least 62%. CONCLUSIONS: Our data suggest that SIX3 mutations result in relatively severe HPE and that there is a genotype-phenotype correlation, as shown by functional studies using animal models.

A case of mixed-pattern calcifications in multinodular goiter associated with a benign diagnosis.

BACKGROUND: Calcified nodules are often found in a goiter when performing an ultrasound of the neck. An analysis of different calcification patterns could contribute to discriminating between nodules with a lower malignancy risk and those with a higher malignancy risk. In certain cases, the results of a simple cytological analysis of a nodule are not specific enough to be completely trusted. CASE PRESENTATION: We present the case of a goiter with a mixed calcification pattern, including a type of calcification that is strongly associated with a malignant diagnosis, for which a completely benign diagnosis was determined. CONCLUSION: We believe that further studies examining a combination of ultrasound (US) and computed tomography (CT) scan presentations of thyroid nodules need to be performed.

Georg Schmorl on trophoblasts in the maternal circulation.

Trafficking of cells between the fetus and its mother provides indirect clues to the underlying pathophysiology of pregnancy. Georg Schmorl first documented the presence of fetal cells in the maternal body and emphasized the importance of the placenta in eclampsia. Although his classic paper, written in 1893, is widely cited today, few investigators have actually read the paper, as it was published in German [Schmorl G., Pathologisch-anatomische Untersuchungen über Puerperal-Eklampsie. Verlag FCW Vogel, Leipzig; 1893]. Our goal was to translate the paper into English and critically re-evaluate its conclusions from a 21st century perspective. Schmorl was remarkably astute in his assessment of the pathologic changes that were seen in the 17 women on whom he performed complete autopsies. He found similar severe changes in all of the women, implying a common pathogenesis. This was in direct contrast to the then current doctrine. He was the first to observe the presence of thrombi containing multinucleated syncytial giant cells in the lungs of the women and speculated that they were of placental origin. To support his hypothesis he performed animal experiments. He also recognized that feto-maternal trafficking occurred in normal gestations but was increased in pregnancies affected by eclampsia. Using sophisticated molecular techniques we can now precisely confirm what Schmorl so elegantly described.

A coupled human-Earth model perspective on long-term trends in the global marine fishery.

The global wild marine fish harvest increased fourfold between 1950 and a peak value near the end of the 20th century, reflecting interactions between anthropogenic and ecological forces. Here, we examine these interactions in a bio-energetically constrained, spatially and temporally resolved model of global fisheries. We conduct historical hindcasts with the model, which suggest that technological progress can explain most of the 20th century increase of fish harvest. In contrast, projections extending this rate of technological progress into the future under open access suggest a long-term decrease in harvest due to over-fishing. Climate change is predicted to gradually decrease the global fish production capacity, though our model suggests that this is of secondary importance to social and economic factors. Our study represents a novel way to integrate human-ecological interactions within a single model framework for long-term simulations.

Paediatric HUS Cases Related to the Consumption of Raw Milk Sold by Vending Machines in Italy: Quantitative Risk Assessment Based on Escherichia coli O157 Official Controls over 7 years.

A quantitative risk assessment (RA) was developed to estimate haemolytic-uremic syndrome (HUS) cases in paediatric population associated with the consumption of raw milk sold in vending machines in Italy. The historical national evolution of raw milk consumption phenomenon since 2008, when consumer interest started to grow, and after 7 years of marketing adjustment, is outlined. Exposure assessment was based on the official Shiga toxin-producing Escherichia coli O157:H7 (STEC) microbiological records of raw milk samples from vending machines monitored by the regional Veterinary Authorities from 2008 to 2014, microbial growth during storage, consumption frequency of raw milk, serving size, consumption preference and age of consumers. The differential risk considered milk handled under regulation conditions (4°C throughout all phases) and the worst time-temperature field handling conditions detected. In case of boiling milk before consumption, we assumed that the risk of HUS is fixed at zero. The model estimates clearly show that the public health significance of HUS cases due to raw milk STEC contamination depends on the current variability surrounding the risk profile of the food and the consumer behaviour has more impact than milk storage scenario. The estimated HUS cases predicted by our model are roughly in line with the effective STEC O157-associated HUS cases notified in Italy only when the proportion of consumers not boiling milk before consumption is assumed to be 1%. Raw milk consumption remains a source of E. coli O157:H7 for humans, but its overall relevance is likely to have subsided and significant caution should be exerted for temporal, geographical and consumers behaviour analysis. Health education programmes and regulatory actions are required to educate people, primarily children, on other STEC sources.

Synthesis and antimicrobial activity of pyranobenzoquinones related to the pyranonaphthoquinone antibiotics.

The synthesis and antimicrobial activity of isochromane-type analogs of the pyranonaphthoquinone antibiotics are reported. Isochromane derivatives with (17a, b) and without (22a, b) a C-4 hydroxyl moiety and their corresponding quinones (19a and 23), were prepared. Both quinones exhibited antimicrobial activity against Staphylococcus aureus, Bacillus atrophaeus and Streptococcus agalactiae, while the related isochromanes were inactive. The results suggest that the quinone moiety is important for biological activity while the C-4 hydroxyl may not be essential.