Effect of open windows on airborne contamination and its topographical distribution in the dental operatory.

Aerosols produced by dental handpieces represent a permanent risk of disease transmission in the dental environment. The current study evaluated the effects of natural ventilation (open windows) on Streptococcus mutans airborne contamination by dental handpieces in simulated clinical conditions. A dental phantom was placed on a dental chair at a standard university dental clinic operatory. An S. mutans suspension was infused into the phantom's mouth while an operator performed standardized dental procedures using low (contra-angle) and high speed (turbine) dental handpieces or an ultrasonic scaler, with windows open or closed. Selective medium Petri dishes were placed in 18 sites of the operatory environment to evaluate contamination topographically. Sites were clustered as: wall, floor, ceiling, dental chair, and cabinet. Contamination was expressed as log10 CFU/cm2 . A linear mixed model analysis was used, nesting the sites within each ventilation and handpiece combination. Open windows significantly reduced contamination. The high-speed handpiece provided the highest contamination, followed by the ultrasonic scaler and the low-speed handpiece. Contamination values were much smaller at the ceiling, and much larger at the chair. Opening windows produced more homogeneous contamination of the operatory compared to closed windows. Natural ventilation during dental procedures decreases contamination and affects its topographical distribution.

Genomic insight into Campylobacter jejuni isolated from commercial turkey flocks in Germany using whole-genome sequencing analysis.

Campylobacter (C.) jejuni is a zoonotic bacterium of public health significance. The present investigation was designed to assess the epidemiology and genetic heterogeneity of C. jejuni recovered from commercial turkey farms in Germany using whole-genome sequencing. The Illumina MiSeq® technology was used to sequence 66 C. jejuni isolates obtained between 2010 and 2011 from commercial meat turkey flocks located in ten German federal states. Phenotypic antimicrobial resistance was determined. Phylogeny, resistome, plasmidome and virulome profiles were analyzed using whole-genome sequencing data. Genetic resistance markers were identified with bioinformatics tools (AMRFinder, ResFinder, NCBI and ABRicate) and compared with the phenotypic antimicrobial resistance. The isolates were assigned to 28 different sequence types and 11 clonal complexes. The average pairwise single nucleotide-polymorphisms distance of 14,585 SNPs (range: 0-26,540 SNPs) revealed a high genetic distinction between the isolates. Thirteen virulence-associated genes were identified in C. jejuni isolates. Most of the isolates harbored the genes flaA (83.3%) and flaB (78.8%). The wlaN gene associated with the Guillain-Barré syndrome was detected in nine (13.6%) isolates. The genes for resistance to ampicillin (bla OXA), tetracycline [tet(O)], neomycin [aph(3')-IIIa], streptomycin (aadE) and streptothricin (sat4) were detected in isolated C. jejuni using WGS. A gene cluster comprising the genes sat4, aph(3')-IIIa and aadE was present in six isolates. The single point mutation T86I in the housekeeping gene gyrA conferring resistance to quinolones was retrieved in 93.6% of phenotypically fluoroquinolone-resistant isolates. Five phenotypically erythromycin-susceptible isolates carried the mutation A103V in the gene for the ribosomal protein L22 inferring macrolide resistance. An assortment of 13 ß-lactam resistance genes (bla OXA variants) was detected in 58 C. jejuni isolates. Out of 66 sequenced isolates, 28 (42.4%) carried plasmid-borne contigs. Six isolates harbored a pTet-like plasmid-borne contig which carries the tet(O) gene. This study emphasized the potential of whole-genome sequencing to ameliorate the routine surveillance of C. jejuni. Whole-genome sequencing can predict antimicrobial resistance with a high degree of accuracy. However, resistance gene databases need curation and updates to revoke inaccuracy when using WGS-based analysis pipelines for AMR detection.

Epidemiological Analysis on the Occurrence of Salmonella enterica Subspecies enterica Serovar Dublin in the German Federal State Schleswig-Holstein Using Whole-Genome Sequencing.

The cattle-adapted serovar Salmonella Dublin (S. Dublin) causes enteritis and systemic diseases in animals. In the German federal state Schleswig-Holstein, S. Dublin is the most important serovar in cattle indicating an endemic character of the infection. To gain information on dissemination and routes of infection, whole-genome sequencing (WGS) was used to explore the genetic traits of 78 S. Dublin strains collected over a period of six years. The phylogeny was analysed using core-genome single nucleotide polymorphisms (cgSNPs). Genomic clusters at 100, 15 and 1 cgSNPs were selected for molecular analysis. Important specific virulence determinants were detected in all strains but multidrug resistance in S. Dublin organisms was not found. Using 15 cgSNPs epidemiological links between herds were identified, clusters at 1 cgSNPs provided clear evidence on both persistence of S. Dublin at single farms in consecutive years and transmission of the organisms between herds in different distances. A possible risk factor for the repeated occurrence of S. Dublin in certain districts of Schleswig-Holstein might be the spreading of manure on pastures and grassland. Effective control of S. Dublin requires farm-specific analysis of the management supplemented by WGS of outbreak causing S. Dublin strains to clearly identify routes of infection.

Ameliorative Effects of Daphnopsis costaricensis Extract against Oxazolone-Induced Atopic Dermatitis-like Lesions in BALB/c Mice.

The genus Daphnopsis has been traditionally used as a purgative, diuretic, stimulant, and psoriasis treatment. In this study, the anti-AD (atopic dermatitis) activities of the Daphnopsis costaricensis EtOH extract (DCE) were investigated in an oxazolone (OX)-induced mouse model of AD, and the anti-inflammatory effects of its active compounds were confirmed in PI-sensitized or IgE/DNP-BSA-sensitized RBL-2H3 cells. DCE improved the symptoms of OX-induced inflammatory dermatitis (swelling, erythema, and increased ear thickening) in OX-induced BALB/c mice ears and reduced epidermal thickness and mast cell infiltration. Eleven flavonoid compounds were isolated from DCE, and two compounds (7,8-dimethoxyflavone and 7,2'-dimethoxyflavone) significantly inhibited IL-4 overexpression in PI-induced RBL-2H3 cells and mast cell degranulation in IgE + DNP-BSA-induced RBL-2H3 cells. Our study indicates that DCE and two compounds (7,8-dimethoxyflavone and 7,2'-dimethoxyflavone) might effectively improve inflammatory and atopic skin symptoms.

Different Phenotypes of Schimke Immuno-Osseous Dysplasia (SIOD) in Two Sisters with the Same Mutation in the SMARCAL1 Gene.

BACKGROUND: Schimke immuno-osseous dysplasia (SIOD) is a very rare autosomal recessive genetic disease caused by mutations in the SMARCAL1 gene. It is characterized by spondyloepiphyseal dysplasia, T-cell immunodeficiency, hypercromic nevi, hypercholestero-lemia, and steroid-resistant nephrotic syndrome with progressive renal failure to end-stage kidney disease. CASE PRESENTATION: We report two cases of SIOD in sisters, diagnosed after the debut of nephrotic syndrome. Both had a personal history of short stature, acetabular hip dysplasia, and hypercholesterolemia. The first case, a 6-year-old girl, presented peripheral refractory edema, severe arterial hypertension, and progressive decrease of the glomerular filtration rate. Steroid-resistance of nephrotic syndrome was confirmed, treated with tacrolimus without response. Renal function worsened over the following 4 months, so haemodialysis was started. Her sister, a 5-year-old girl, had the steroid-resistant nephrotic syndrome and normal blood pressure and renal function under enalapril treatment. In view of the suspicion of SIOD, genetic studies were carried out, revealing the same mutation in homozygosis. CONCLUSION: SIOD has a variable expression with multi-systemic involvement with a short life expectancy. Early diagnosis is important, which can encourage the early start of treatment and anticipation of complications that may be life-threatening.

Left Ventricular Hypertrophy in Patients with X-Linked Hypophosphataemia

X-linked hypophosphatemia (XLH) is a rare genetic disorder with X-linked dominant inheritance. Mutations in the PHEX gene increase fibroblast growth factor 23 (FGF23) concentrations, causing loss of phosphorus at the proximal tubule. Most pediatric patients debut in the first two years with short stature and bowed legs. Conventional treatment consists of oral supplements with phosphorus and calcitriol. Since 2018, burosumab has been approved as a novel therapeutic option for XLH, with promising results. The purpose of this study was to share our experience with two cases of XLH treated with burosumab. These patients presented with a broad phenotypical differences. One had the most severe radiological phenotype and developed left ventricular hypertrophy (LVH) and left ventricular dysfunction with preserved ejection fraction. Treatment with burosumab was well-tolerated and was followed by radiological stability and a striking improvement in both blood biochemistry and quality of life. The LVH was stable and left ventricular function normalized in the patient with cardiac involvement. In recent years many studies have been carried out to explain the role of FGF23 in cardiovascular damage, but the exact pathophysiological mechanisms are as yet unclear. The most intensively studied populations are patients with XLH or chronic kidney disease, as both are associated with high levels of FGF23. To date, cardiovascular involvement in XLH has been described in patients treated with conventional treatment, so it would be of interest to investigate if early use of burosumab at the time of diagnosis of XLH would prevent the occurrence of cardiovascular manifestations.

Evidence-based medicine in neurosurgery: why and how?

Since its inception, medical training and practice are based primarily on the clinical experience provided by the mentors of each of the medical schools. In the 1990s, the first steps were taken for the construction of what we now know as evidence-based medicine. Evidence-based medicine is the set of studies, methods, and principles for the prevention of medical diseases, management guidelines, and algorithms used in sources of evidence. Neurosurgery based on evidence has emerged thanks to advances in neuroscience and information technology that allows the globalization of current scientific information. The results of important reviews on the levels of evidence in neurosurgery are low in percentages of high-quality evidence in this field of medicine. Based on the above, the aim of this manuscript was to describe the application of evidence in neurosurgery, the current state of the art in evidence-based medicine, and the steps needed to create evidence of the best quality in neurosurgery.

Genomic Characterization of Multidrug-Resistant Salmonella Serovars Derby and Rissen From the Pig Value Chain in Vietnam.

Nontyphoidal Salmonella (NTS) is the most reported cause of bacterial foodborne zoonoses in Vietnam, and contaminated pork is one of the main sources of human infection. In recent years, the prevalence of NTS carrying multiple antimicrobial resistance genes (ARGs) have been increased. The genomic characterization along the pig value chain and the identification of ARGs and plasmids have the potential to improve food safety by understanding the dissemination of ARGs from the farm to the table. We report an analysis of 13 S. Derby and 10 S. Rissen isolates, collected in 2013 at different stages in Vietnamese slaughterhouses and markets. VITEK 2 Compact System was used to characterize the phenotypical antimicrobial resistance of the isolates. In addition, whole-genome sequencing (WGS) was used to detect ARGs and plasmids conferring multidrug resistance. Whole genome single nucleotide polymorphism typing was used to determine the genetic diversity of the strains and the spread of ARGs along the pig value chain. Altogether, 86.9% (20/23) of the samples were resistant to at least one antibiotic. Resistance to ampicillin was most frequently detected (73.9%), followed by piperacillin and moxifloxacin (both 69.6%). At least one ARG was found in all strains, and 69.6% (16/23) were multidrug-resistant (MDR). The observed phenotype and genotype of antimicrobial resistance were not always concordant. Plasmid replicons were found in almost all strains [95.6% (22/23)], and the phylogenetic analysis detected nine clusters (S. Derby, n = 5; S. Rissen, n = 4). ARGs and plasmid content were almost identical within clusters. We found six MDR IncHI1s with identical plasmid sequence type in strains of different genetic clusters at the slaughterhouse and the market. In conclusion, high rates of multidrug resistance were observed in Salmonella strains from Vietnam in 2013. Genomic analysis revealed many resistance genes and plasmids, which have the potential to spread along the pig value chain from the slaughterhouse to the market. This study pointed out that bioinformatics analyses of WGS data are essential to detect, trace back, and control the MDR strains along the pig value chain. Further studies are necessary to assess the more recent MDR Salmonella strains spreading in Vietnam.

Epidemiological Analysis of Salmonella enterica subsp. enterica Serovar Dublin in German Cattle Herds Using Whole-Genome Sequencing.

Salmonella enterica subsp. enterica serovar Dublin is a cattle-adapted serovar that causes enteritis and systemic diseases in animals. In Germany, S. Dublin is not detected or is very rarely detected in some federal states but is endemic in certain regions. Information on detailed genetic characteristics of S. Dublin is not available. An understanding of the paths and spreading of S. Dublin within and between regions and over time is essential to establish effective control strategies. Whole-genome sequencing (WGS) and bioinformatic analysis were used to explore the genetic traits of S. Dublin and to determine their epidemiological context. Seventy-four S. Dublin strains collected in 2005 to 2018 from 10 federal states were studied. The phylogeny was analyzed using core-genome single-nucleotide polymorphisms (cgSNPs) and core-genome multilocus sequence typing. Genomic clusters at 100 cgSNPs, 40 cgSNPs, and 15 cgSNPs were selected for molecular epidemiology. WGS-based genoserotyping confirmed serotyping. Important specific virulence determinants were detected in all strains, but multidrug resistance in German S. Dublin organisms is uncommon. Use of different thresholds for cgSNP analysis enabled a broad view and also a detailed view of the occurrence of S. Dublin in Germany. Genomic clusters could be allocated nationwide, to a limited number of federal states, or to special regions only. Results indicate both persistence and spread of S. Dublin within and between federal states in short and longer time periods. However, to detect possible routes of infection or persistence of S. Dublin indicated by genomic analysis, information on the management of the cattle farms and contacts with corresponding farms are essential. IMPORTANCE Salmonella enterica subsp. enterica serovar Dublin is a bovine host-adapted serovar that causes up to 50% of all registered outbreaks of salmonellosis in cattle in Germany. S. Dublin is not detected or is only rarely detected in some federal states but has been endemic in certain regions of the country for a long time. Information on genetic traits of the causative strains is essential to determine routes of infection. WGS and bioinformatic analysis should be used to explore the genetic characteristics of S. Dublin. Combining the genomic features of S. Dublin strains with information on the management of the cattle farms concerned should enable the detection of possible routes of infection or persistence of S. Dublin. This approach is regarded as a prerequisite to developing effective intervention strategies.

Salmonella Derby: A Comparative Genomic Analysis of Strains From Germany.

Salmonella enterica subspecies enterica serovar Derby (S. Derby) is one of the most frequent causes for salmonellosis in humans and animals. Understanding the genetic diversity of S. Derby, as well as the nature and origin of its resistance to antimicrobial treatment are thus the key to epidemiological control and surveillance. Here, we report an analysis of 15 S. Derby strains isolated from pig and cattle in slaughterhouses across Germany (2000-2015), which belonged to multilocus sequence types (ST) ST39, ST40 and ST682. Strains were compared to publicly available S. Derby sequence data of these three STs from Germany, comprising 65 isolates collected between 2004 and 2018 from different sources (i.e., pigs, humans, cattle, wild boar, and poultry). A total of 80 sequences (ST39 = 34, ST40 = 21, and ST682 = 25) were analyzed to assess genetic diversity, to identify virulence-associated and antimicrobial resistance genes (ARGs), and to characterize plasmid content. Strains belonging to all three STs were identified in each source examined. Strains with the same ST were closely related regardless of origin. Altogether, 72.5% of the isolates carried at least one resistance gene, furthermore ST40 carried most of the ARGs and the plasmid replicons. The IncI1 replicon was detected in eleven isolates, four of them carried IncI1 plasmid ST26 with clonal complex 2. The comparison of these four isolates with an IncI1 ST26 plasmid reported in 2010 from a German pig (JX566770), showed only variations in a region carrying different ARGs and mobile genetic elements. The strains of our collection had similar genetic diversity as the strains taken from the public database. Moreover, we found that strains harboring multidrug resistant IncI plasmid were found in different animal species, indicating that S. Derby may be implicated in the spread of antimicrobial resistance among animal species. Results may contribute to the knowledge about the diversity in S. Derby in Germany, which may be useful for the future surveillance and antimicrobial resistance of this serovar.

Molecular detection of extended spectrum ß-lactamase genes in Escherichia coli clinical isolates from diarrhoeic children in Kano, Nigeria.

The increase in antimicrobial resistance in developed and developing countries is a global public health challenge. In this context ß-lactamase production is a major contributing factor to resistance globally. The aim of this study was to determine the prevalence of phenotypic and genotypic extended spectrum ß-lactamases (ESBLs) in 296 E. coli isolates recovered from diarrhoeic children younger than five years in Kano whose susceptibility profile against 7 antimicrobials had been determined. The E. coli isolates were subjected to double disc synergy test for phenotypic ESBLs detection and ESBL associated genes (blaCTX-M, blaTEM and blaSHV) were detected using conventional PCR. Phenotypically, 12.8% (38/296) E. coli isolates presented a ESBLs phenotype, with a significantly higher proportion in isolates from females compared with males (P-value = 0.024). blaCTX-M 73.3% and blaTEM 73.3% were the predominant resistance genes in the ESBLs positive E. coli (each detected in 22/30 isolates, of which 14 harboured both). In addition, 1/30 harboured blaCTX-M + blaTEM + blaSHV genes simultaneously. This study demonstrates the presence of ESBLs E. coli isolates in clinically affected children in Kano, and demonstrates the circulation of blaCTX-M and blaTEM associated with those phenotypes. Enactment of laws on prudent antibiotic use is urgently needed in Kano.

Lung ultrasound score and diuretics in preterm infants born before 32 weeks: A pilot study.

OBJECTIVE: To describe if weekly determined lung ultrasound (LU) scores in preterm infants born before 32 weeks (PTB32W) change with diuretic therapy. DESIGN: We included infants who received diuretics and compared LU scores according to their evolution on respiratory support (RS) before and after diuretics. RESULTS: We included 18 PTB32W divided into two groups. Both groups were similar in terms of median gestational age: 26 weeks (interquartile range [IQR]: 25-28) in the responders' group and 27 weeks (IQR: 24-28) in the other. They differed, however, in the median number of days on invasive mechanical ventilation: 27 (IQR: 11-43) versus 76 (IQR: 35-117), p = .03; in addition to the number of infants with moderate-severe bronchopulmonary dysplasia: 3 (33%) versus 8 (89%), p = .025. The responders' group showed lower LU scores 2 days after diuretics, with a median LU score of 6 (IQR: 3-12) versus 14 (IQR: 12-17) in the nonresponders group, p = .03; 1 week after (3 [IQR: 0-10] versus 12 [12-12], p = .04); and 3 weeks after (5 [IQR: 3-6] versus 12 [10-15], p = .01). RS also decreased at the same time: 7 out of 9 (78%) were extubated in the responders' group, and 1 out of 9 (11%) in the nonresponders group, p = .02, and these differences remained throughout the entire follow-up. CONCLUSIONS: There is a group of PTB32W patients whose LU score improves after diuretics. This change appears only in those patients that can be weaned off from RS, and at the same period of time as the administration of diuretics.

Emergence of Multidrug-Resistant Salmonella enterica Subspecies enterica Serovar Infantis of Multilocus Sequence Type 2283 in German Broiler Farms.

During the last decade, Salmonella enterica subspecies enterica serovar Infantis (S. Infantis) has become more prevalent across Europe with an increased capability to persist in broiler farms. In this study, we aimed to identify potential genetic causes for the increased emergence and longer persistence of S. Infantis in German poultry farms by high-throughput-sequencing. Broiler derived S. Infantis strains from two decades, the 1990s (n = 12) and the 2010s (n = 18), were examined phenotypically and genotypically to detect potential differences responsible for increased prevalence and persistence. S. Infantis organisms were characterized by serotyping and determining antimicrobial susceptibility using the microdilution method. Genotypic characteristics were analyzed by whole genome sequencing (WGS) to detect antimicrobial resistance and virulence genes as well as plasmids. To detect possible clonal relatedness within S. Infantis organisms, 17 accessible genomes from previous studies about emergent S. Infantis were downloaded and analyzed using complete genome sequence of SI119944 from Israel as reference. In contrast to the broiler derived antibiotic-sensitive S. Infantis strains from the 1990s, the majority of strains from the 2010s (15 out of 18) revealed a multidrug-resistance (MDR) phenotype that encodes for at least three antimicrobials families: aminoglycosides [ant(3")-Ia], sulfonamides (sul1), and tetracyclines [tet(A)]. Moreover, these MDR strains carry a virulence gene pattern missing in strains from the 1990s. It includes genes encoding for fimbriae clusters, the yersiniabactin siderophore, mercury and disinfectants resistance and toxin/antitoxin complexes. In depth genomic analysis confirmed that the 15 MDR strains from the 2010s carry a pESI-like megaplasmid with resistance and virulence gene patterns detected in the emerged S. Infantis strain SI119944 from Israel and clones inside and outside Europe. Genotyping analysis revealed two sequence types (STs) among the resistant strains from the 2010s, ST2283 (n = 13) and ST32 (n = 2). The sensitive strains from the 1990s, belong to sequence type ST32 (n = 10) and ST1032 (n = 2). Therefore, this study confirms the emergence of a MDR S. Infantis pESI-like clone of ST2283 in German broiler farms with presumably high tendency of dissemination. Further studies on the epidemiology and control of S. Infantis in broilers are needed to prevent the transfer from poultry into the human food chain.

Draft genome sequence of multi-resistant Salmonella enterica subsp. enterica serovar Rissen strain 19CS0416 isolated from Vietnam reveals mcr-1 plasmid mediated resistance to colistin already in 2013.

We report the first draft genome sequence of a Salmonella strain with plasmid-mediated resistance to colistin encoded by mcr-1 gene in Vietnam. Salmonella enterica subsp. enterica serovar Rissen was isolated from a Vietnamese pig slaughterhouse in 2013. We can confirm that mcr-1 gene is identical to the first reported mcr-1 gene of the Escherichia coli strain SHP45, isolated in 2015 from a Chinese pig. The plasmid containing this gene in the strain 19CS0416 was highly related (96.86% identity) to the plasmid (pHNSHP45) contained in this Chinese strain. Moreover, this plasmid was determined to be 100% identical to a plasmid (p13P477T-7) belonging to an Escherichia coli (13P477T) found in Hong Kong during the same year in pigs. Our results will aid in understanding the dissemination of mcr-1 gene in East Asia, dating back to as early as 2013.

Metabolome-microbiome signatures in the fermented beverage, Kombucha.

Kombucha is a fermented tea. Here we investigate the fermentation kinetics, metabolite production, microbiome and potential health promoting properties of three different kombucha consortia. Shotgun metagenomic sequencing revealed several dominant bacterial genera such as Komagataeibacter, Gluconacetobacter and Gluconobacter. Brettanomyces and Schizosaccharomyces were the most dominant yeasts identified. Species distribution reflected different patterns of sugar consumption, with S. pombe being present in samples with the highest sugar conversion. Liquid-liquid extractions were performed with organic solvents in order to obtain dried extracts, which were later characterized. HPLC-DAD and GC-MS analysis revealed differences in the production of organic acids, sugars, alcohols and phenolic compounds, where the presence of caffeine, propanoic acid and 2,3 butanediol differ greatly across the three kombuchas. Metabolomic analysis exhibited a link between the microbiota and the production of bioactive compounds in kombucha fermentation. In vitro assays were carried out in order to evaluate potential health-promoting features of the fermented teas, with notable outcomes including antioxidant ability against DPPH radical and against the 15-lipoxygenase enzyme, indicating a potential anti-inflammatory activity. These investigations considerably enhance our understanding of the relationship between the microbiota and metabolites as well as health promoting potential of kombucha and have the potential for the development of future generations of kombucha products in which these relationships are optimized.