scholarly journals KlebsiellaandProvidenciaemerge as lone survivors following long-term starvation of oral microbiota

2019 ◽  
Vol 116 (17) ◽  
pp. 8499-8504 ◽  
Author(s):  
Jonathon L. Baker ◽  
Erik L. Hendrickson ◽  
Xiaoyu Tang ◽  
Renate Lux ◽  
Xuesong He ◽  
...  
Keyword(s):  
Klebsiella Oxytoca ◽  
Oral Microbiota ◽  
Nucleotide Polymorphisms ◽  
Human Pathogens ◽  
Oral Fluids ◽  
Providencia Alcalifaciens ◽  
Fold Reduction ◽  
Death Phase ◽  
Ecological Success

It is well-understood that many bacteria have evolved to survive catastrophic events using a variety of mechanisms, which include expression of stress-response genes, quiescence, necrotrophy, and metabolic advantages obtained through mutation. However, the dynamics of individuals leveraging these abilities to gain a competitive advantage in an ecologically complex setting remain unstudied. In this study, we observed the saliva microbiome throughout the ecological perturbation of long-term starvation, allowing only the species best equipped to access and use the limited resources to survive. During the first several days, the community underwent a death phase that resulted in a ∼50–100-fold reduction in the number of viable cells. Interestingly, after this death phase, only three species,Klebsiella pneumoniae,Klebsiella oxytoca, andProvidencia alcalifaciens, all members of the family Enterobacteriaceae, appeared to be transcriptionally active and recoverable.Klebsiellaare significant human pathogens, frequently resistant to multiple antibiotics, and recently, ectopic colonization of the gut by oralKlebsiellawas documented to induce dysbiosis and inflammation. MetaOmics analyses provided several leads for further investigation regarding the ecological success of the Enterobacteriaceae. The isolates accumulated single nucleotide polymorphisms in known growth advantage in stationary phase alleles and produced natural products closely resembling antimicrobial cyclic depsipeptides. The results presented in this study suggest that pathogenic Enterobacteriaceae persist much longer than their more benign neighbors in the salivary microbiome when faced with starvation. This is particularly significant, given that hospital surfaces contaminated with oral fluids, especially sinks and drains, are well-established sources of outbreaks of drug-resistant Enterobacteriaceae.

scholarly journals Facile Use of ZnO Nanopowders to Protect Old Manual Paper Documents

Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5452
Author(s):  
Ludmila Motelica ◽  
Aurelian Popescu ◽  
Anca-Gabriela Răzvan ◽  
Ovidiu Oprea ◽  
Roxana-Doina Truşcă ◽  
...  
Keyword(s):  
Hand Hygiene ◽  
Antimicrobial Agents ◽  
Storage Conditions ◽  
Human Pathogens ◽  
Accessible Method

One of the main problems faced by libraries, archives and collectors is the mold degradation of the paper-based documents, books, artworks etc. Microfungi (molds) emerge in regular storage conditions of such items (humidity, usually over 50%, and temperatures under 21 °C). If the removal of the visible mycelium is relatively easy, there is always the problem of the subsequent appearance of mold as the spores remain trapped in the cellulosic, fibrillary texture, which acts as a net. Moreover, due to improper hand hygiene bacteria contamination, old books could represent a source of biohazard, being colonized with human pathogens. An easy and accessible method of decontamination, which could offer long term protection is therefore needed. Here, we present a facile use of the ZnO nanopowders as antimicrobial agents, suitable for cellulose-based products, conferring an extended antibacterial and anti-microfungal effect. The proposed method does not adversely impact on the quality of the cellulose documents and could be efficiently used for biodegradation protection.

scholarly journals Cariogenic Biofilm: Pathology-Related Phenotypes and Targeted Therapy

2021 ◽  
Vol 9 (6) ◽  
pp. 1311
Author(s):  
Xiuqin Chen ◽  
Eric Banan-Mwine Daliri ◽  
Akanksha Tyagi ◽  
Deog-Hwan Oh
Keyword(s):  
Treatment Strategies ◽  
High Specificity ◽  
Low Ph ◽  
Oral Microbiota ◽  
Extracellular Polymers ◽  
Dental Biofilm ◽  
Health And Disease ◽  
Promising Treatment ◽  
Cariogenic Biofilm

The initiation and development of cariogenic (that is, caries-related) biofilms are the result of the disruption of homeostasis in the oral microenvironment. There is a daily accumulation of dental biofilm on the surface of teeth and its matrix of extracellular polymers supports the host in its defense against invading microbes, thus helping to achieve oral microbial homeostasis. However, the homeostasis can be broken down under certain circumstances such as during long-term exposure to a low pH environment which results in the dominance of acidogenic and acid-tolerating species in the dental biofilm and, thus, triggers the shift of harmless biofilm to an acidic one. This work aims to explore microbial diversity and the quorum sensing of dental biofilm and their important contributions to oral health and disease. The complex and multispecies ecosystems of the cariogenic biofilm pose significant challenges for the modulation of the oral microenvironment. Promising treatment strategies are those that target cariogenic niches with high specificity without disrupting the balance of the surrounding oral microbiota. Here, we summarized the recent advances in modulating cariogenic biofilm and/or controlling its pathogenic traits.

scholarly journals Cumulative incidence and risk factors for radiation induced leukoencephalopathy in high grade glioma long term survivors

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Robert Terziev ◽  
Dimitri Psimaras ◽  
Yannick Marie ◽  
Loic Feuvret ◽  
Giulia Berzero ◽  
...  
Keyword(s):  
Risk Factors ◽  
Cumulative Incidence ◽  
High Grade Glioma ◽  
High Grade ◽  
Nucleotide Polymorphisms ◽  
Increased Risk ◽  
Radiation Induced ◽  
Long Term Survivors

AbstractThe incidence and risk factors associated with radiation-induced leukoencephalopathy (RIL) in long-term survivors of high-grade glioma (HGG) are still poorly investigated. We performed a retrospective research in our institutional database for patients with supratentorial HGG treated with focal radiotherapy, having a progression-free overall survival > 30 months and available germline DNA. We reviewed MRI scans for signs of leukoencephalopathy on T2/FLAIR sequences, and medical records for information on cerebrovascular risk factors and neurological symptoms. We investigated a panel of candidate single nucleotide polymorphisms (SNPs) to assess genetic risk. Eighty-one HGG patients (18 grade IV and 63 grade III, 50M/31F) were included in the study. The median age at the time of radiotherapy was 48 years old (range 18–69). The median follow-up after the completion of radiotherapy was 79 months. A total of 44 patients (44/81, 54.3%) developed RIL during follow-up. Twenty-nine of the 44 patients developed consistent symptoms such as subcortical dementia (n = 28), gait disturbances (n = 12), and urinary incontinence (n = 9). The cumulative incidence of RIL was 21% at 12 months, 42% at 36 months, and 48% at 60 months. Age > 60 years, smoking, and the germline SNP rs2120825 (PPARg locus) were associated with an increased risk of RIL. Our study identified potential risk factors for the development of RIL (age, smoking, and the germline SNP rs2120825) and established the rationale for testing PPARg agonists in the prevention and management of late-delayed radiation-induced neurotoxicity.

scholarly journals SUN-207 Modelling Long Term Glucocorticoid-Induced HPA Axis Suppression in Mice

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Nicola Romano ◽  
Peter James Duncan ◽  
Oscar Nolan ◽  
Paul Roussel Le Tissier ◽  
Mike Shipston ◽  
...  
Keyword(s):  
Drinking Water ◽  
Mouse Model ◽  
Hpa Axis ◽  
Adult Male ◽  
Male Mice ◽  
Dexamethasone Treatment ◽  
Mortality And Morbidity ◽  
Fold Reduction ◽  
The Uk

Abstract Glucocorticoids are prescribed for >3 months to 1% of the UK population. 10-50% of these long-term glucocorticoid treated patients develop persistent HPA axis suppression associated with mortality and morbidity. We have developed a mouse model of glucocorticoid-induced HPA axis dysfunction to determine the mechanisms resulting in persistent HPA axis suppression. Experiment 1: 36 C57BL/6 adult male mice received Dexamethasone (DEX,~10µg/day) or vehicle (CTL) via drinking water for 28 days, following which treatment was stopped and tissues were harvested at 0, 7 and 28 days. DEX suppressed waking serum corticosterone at days 0 and 7, recovering by day 28. Adrenal size remained lower 28 days following DEX withdrawal. DEX had no effect on whole pituitary pomc, nr3c1 or crhr1 expression, although avpr1b was increased at day 0. In the adrenal, hsd3b2 and cyp11a1 expression were reduced at time 0; normalising by 28 days. Experiment 2: 24 POMC-GFP male mice were treated as above. Tissues were collected at day 0 (n=6), 7 (n=3) and 10 (n=3) following withdrawal. Pooled corticotrophs (groups of 3) were isolated by FACS and RNA extracted for qPCR. DEX reduced corticotroph pomc expression at time 0 (x20 fold reduction), with x5 fold suppression at day 7, which recovered with evidence of compensation by day 10. DEX increased expression of avpr1b but not crhr1. CONCLUSION: 28 days dexamethasone treatment in mice suppresses the HPA axis. HPA suppression is evident 7 days following withdrawal of dexamethasone in the adrenal, corticotroph population and corticosterone production. Further analysis will determine mechanisms for delays in HPA axis recovery.

scholarly journals Long-Term Reciprocal Gene Flow in Wild and Domestic Geese Reveals Complex Domestication History

2020 ◽  
Vol 10 (9) ◽  
pp. 3061-3070 ◽  
Author(s):  
Marja E Heikkinen ◽  
Minna Ruokonen ◽  
Thomas A White ◽  
Michelle M Alexander ◽  
İslam Gündüz ◽  
...  
Keyword(s):  
Gene Flow ◽  
Wild Form ◽  
Nucleotide Polymorphisms ◽  
Anser Anser ◽  
Domestic Species ◽  
Genome Wide ◽  
Domestication Process ◽  
Historical Writings ◽  
The Impact

Abstract Hybridization has frequently been observed between wild and domestic species and can substantially impact genetic diversity of both counterparts. Geese show some of the highest levels of interspecific hybridization across all bird orders, and two of the goose species in the genus Anser have been domesticated providing an excellent opportunity for a joint study of domestication and hybridization. Until now, knowledge of the details of the goose domestication process has come from archaeological findings and historical writings supplemented with a few studies based on mitochondrial DNA. Here, we used genome-wide markers to make the first genome-based inference of the timing of European goose domestication. We also analyzed the impact of hybridization on the genome-wide genetic variation in current populations of the European domestic goose and its wild progenitor: the graylag goose (Anser anser). Our dataset consisted of 58 wild graylags sampled around Eurasia and 75 domestic geese representing 14 breeds genotyped for 33,527 single nucleotide polymorphisms. Demographic reconstruction and clustering analysis suggested that divergence between wild and domestic geese around 5,300 generations ago was followed by long-term genetic exchange, and that graylag populations have 3.2–58.0% admixture proportions with domestic geese, with distinct geographic patterns. Surprisingly, many modern European breeds share considerable (> 10%) ancestry with the Chinese domestic geese that is derived from the swan goose Anser cygnoid. We show that the domestication process can progress despite continued and pervasive gene flow from the wild form.

scholarly journals Multifactorial Activation of NLRP3 Inflammasome: Relevance for a Precision Approach to Atherosclerotic Cardiovascular Risk and Disease

2020 ◽  
Vol 21 (12) ◽  
pp. 4459 ◽  
Author(s):  
Andrea Baragetti ◽  
Alberico Luigi Catapano ◽  
Paolo Magni
Keyword(s):  
Cardiovascular Disease ◽  
Oral Microbiota ◽  
Low Grade ◽  
Atherosclerotic Cardiovascular Disease ◽  
Nucleotide Polymorphisms ◽  
Cvd Risk ◽  
Number Of Factors ◽  
Elevated Cholesterol ◽  
Inflammatory Pattern ◽  
Low Grade Inflammation

Chronic low-grade inflammation, through the specific activation of the NACHT leucine-rich repeat- and PYD-containing (NLRP)3 inflammasome-interleukin (IL)-1β pathway, is an important contributor to the development of atherosclerotic cardiovascular disease (ASCVD), being triggered by intracellular cholesterol accumulation within cells. Within this pathological context, this complex pathway is activated by a number of factors, such as unhealthy nutrition, altered gut and oral microbiota, and elevated cholesterol itself. Moreover, evidence from autoinflammatory diseases, like psoriasis and others, which are also associated with higher cardiovascular disease (CVD) risk, suggests that variants of NLRP3 pathway-related genes (like NLRP3 itself, caspase recruitment domain-containing protein (CARD)8, caspase-1 and IL-1β) may carry gain-of-function mutations leading, in some individuals, to a constitutive pro-inflammatory pattern. Indeed, some reports have recently associated the presence of specific single nucleotide polymorphisms (SNPs) on such genes with greater ASCVD prevalence. Based on these observations, a potential effective strategy in this context may be the identification of carriers of these NLRP3-related SNPs, to generate a genomic score, potentially useful for a better CVD risk prediction, and, possibly, for personalized therapeutic approaches targeted to the NLRP3-IL-1β pathway.

scholarly journals Next Generation Sequencing Discoveries of the Nitrate-Responsive Oral Microbiome and Its Effect on Vascular Responses

2019 ◽  
Vol 8 (8) ◽  
pp. 1110 ◽  
Author(s):  
Melissa M. Grant ◽  
Daniel Jönsson
Keyword(s):  
Nitric Oxide ◽  
Next Generation Sequencing ◽  
Human Condition ◽  
Oral Microbiome ◽  
Oral Microbiota ◽  
Next Generation ◽  
Contributing Factors ◽  
Future Directions ◽  
Generation Sequencing

Cardiovascular disease is a worldwide human condition which has multiple underlying contributing factors: one of these is long-term increased blood pressure—hypertension. Nitric oxide (NO) is a small nitrogenous radical species that has a number of physiological functions including vasodilation. It can be produced enzymatically through host nitric oxide synthases and by an alternative nitrate–nitrite–NO pathway from ingested inorganic nitrate. It was discovered that this route relies on the ability of the oral microbiota to reduce nitrate to nitrite and NO. Next generation sequencing has been used over the past two decades to gain deeper insight into the microbes involved, their location and the effect of their removal from the oral cavity. This review article presents this research and comments briefly on future directions.

scholarly journals Functional Inflammatory Genotypes in Ischemic Stroke: Could We Use Them to Predict Age of Onset and Long-Term Outcome?

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Stella Marousi ◽  
Anna Antonacopoulou ◽  
Haralambos Kalofonos ◽  
Panagiotis Papathanasopoulos ◽  
Marina Karakantza ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Cox Regression ◽  
Age Of Onset ◽  
Adverse Outcome ◽  
Nucleotide Polymorphisms ◽  
Term Outcome ◽  
Single Nucleotide ◽  
Long Term Outcome ◽  
Tnf Α

Functional single-nucleotide polymorphisms (SNPs) of inflammatory cytokines have been previously related to the occurrence of an ischemic stroke (IS). We investigated whether five functional SNPs (i.e., TNF-α-308G>A, IL6-174G>C, IL12B 1188A>C, IL4-589C>T, and IL10-1082G>A) might be associated with the age of onset and 6-month outcome of an acute IS. A probe-free real-time PCR methodology was used to genotype 145 consecutively admitted cases with a first-ever IS. Simple Kaplan-Mayer and adjusted Cox regression analyses showed no association between inflammatory genotypes and the age of IS onset. IL6-174G>C, IL12B 1188A>C, IL4-589C>T, and IL10-1082G>A were not found to significantly contribute to the long-term outcome of the disease. However, carriage of the TNF-α-308 GG genotype was significantly associated with reduced odds for an adverse outcome. Larger studies are needed to confirm our results.

Dry Stress and Survival Time of Enterobacter sakazakii and Other Enterobacteriaceae in Dehydrated Powdered Infant Formula

2007 ◽  
Vol 70 (9) ◽  
pp. 2111-2117 ◽  
Author(s):  
JUNCAL CAUBILLA BARRON ◽  
STEPHEN J. FORSYTHE
Keyword(s):  
Infant Formula ◽  
Salmonella Enteritidis ◽  
Klebsiella Oxytoca ◽  
Powdered Infant Formula ◽  
Enterobacter Sakazakii ◽  
Opportunistic Pathogens ◽  
Term Survival ◽  
E Coli ◽  
Sterile Product

Powdered infant formula is not a sterile product, and opportunistic pathogens could multiply in the reconstituted product, resulting in neonatal infections. In this study, the generation of sublethally injured Enterobacteriaceae during desiccation and their persistence in dehydrated powdered infant formula was assessed during a 2.5-year period. The study included 27 strains of Enterobacter sakazakii, Enterobacter cloacae, Salmonella Enteritidis, Citrobacter koseri, Citrobacter freundii, Escherichia coli, Escherichia vulneris, Pantoea spp., Klebsiella oxytoca, and Klebsiella pneumoniae. The number of sublethally injured cells generated during desiccation was lower for K. oxytoca, Pantoea spp., Salmonella Enteritidis, and capsulated strains of E. sakazakii than for the other Enterobacteriaceae. The Enterobacteriaceae could be divided into three groups with respect to their long-term survival in the desiccated state. C. freundii, C. koseri, and E. cloacae were no longer recoverable after 6 months, and Salmonella Enteritidis, K. pneumoniae, and E. coli could not be recovered after 15 months. Pantoea spp., K. oxytoca, and E. vulneris persisted over 2 years, and some capsulated strains of E. sakazakii were still recoverable after 2.5 years.

scholarly journals LB1. Regional Assessment and Containment of Candida auris Transmission in Post-Acute Care Settings—Orange County, California, 2019

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S993-S993 ◽  
Author(s):  
Ellora Karmarkar ◽  
Ellora Karmarkar ◽  
Kathleen O’Donnell ◽  
Christopher Prestel ◽  
Kaitlin Forsberg ◽  
...  
Keyword(s):  
Acute Care ◽  
Orange County ◽  
Invasive Disease ◽  
Nucleotide Polymorphisms ◽  
Nursing Facilities ◽  
Candida Auris ◽  
Single Nucleotide ◽  
Skilled Nursing ◽  
And Control

Abstract Background Patients in long-term acute care hospitals (LTACHs) and skilled nursing facilities with ventilator units (VSNFs) are at high risk for Candida auris colonization; among patients colonized with this emerging pathogen, 5%–10% develop invasive disease with >45% mortality. In September 2018, a California LTACH-affiliated laboratory began enhanced C. auris surveillance by classifying species of Candida isolated from routine urine specimens. In February 2019, the first known Southern California case was detected in an Orange County (OC) LTACH; the patient had not traveled outside the region, indicating local acquisition. We performed point prevalence surveys (PPS) and infection prevention (IP) assessments at all OC LTACHs and VSNF subacute units to identify patients colonized with C. auris and control transmission. Methods During March–August 2019, we conducted PPS at facilities by collecting composite axilla and groin swabs for C. auris polymerase chain reaction testing and reflex culture from all patients who assented. Facilities with ≥1 C. auris-colonized patient repeated a PPS every 2 weeks to assess for new transmission. Isolate relatedness was assessed by whole-genome sequencing (WGS). We evaluated hand hygiene (HH) adherence, access to alcohol-based hand rubs (ABHR), and cleaning of high-touch surfaces to guide IP recommendations. Results The first PPS at all OC LTACHs (n = 3) and adult VSNFs (n = 14) identified 45 C. auris-colonized patients in 3 (100%) LTACHs and 6 (43%) VSNFs; after repeated PPS, the total count reached 124. Most patients (70%) were at 2 facilities (Table 1). Three of 124 patients developed candidemia. To date, isolates from 48 patients have completed WGS; all were highly related (<11 single-nucleotide polymorphisms) in the African clade. Of 9 facilities with C. auris, 5 had HH adherence < 50%, 3 had limited ABHR, and at 2, <60% of assessed high-touch surfaces were clean. We recommended regular HH and cleaning audits, and increased ABHR. Conclusion Our investigation, prompted by enhanced surveillance, identified C. auris at 9 OC facilities. WGS indicated a single introduction and local transmission. Early detection, followed by rapid county-wide investigation and IP support, enabled containment efforts for C. auris in OC. Disclosures All authors: No reported disclosures.

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