scholarly journals Options and Limitations in Clinical Investigation of Bacterial Biofilms

2018 ◽  
Vol 31 (3) ◽  
Author(s):  
Maria Magana ◽  
Christina Sereti ◽  
Anastasios Ioannidis ◽  
Courtney A. Mitchell ◽  
Anthony R. Ball ◽  
...  
Keyword(s):  
Clinical Investigation ◽  
Bacterial Biofilm ◽  
Clinical Settings ◽  
Microbial Composition ◽  
The Past ◽  
Methodological Research ◽  
Current Trends ◽  
Literature Searches ◽  
Biofilm Development ◽  
Multispecies Biofilms

SUMMARYBacteria can form single- and multispecies biofilms exhibiting diverse features based upon the microbial composition of their community and microenvironment. The study of bacterial biofilm development has received great interest in the past 20 years and is motivated by the elegant complexity characteristic of these multicellular communities and their role in infectious diseases. Biofilms can thrive on virtually any surface and can be beneficial or detrimental based upon the community's interplay and the surface. Advances in the understanding of structural and functional variations and the roles that biofilms play in disease and host-pathogen interactions have been addressed through comprehensive literature searches. In this review article, a synopsis of the methodological landscape of biofilm analysis is provided, including an evaluation of the current trends in methodological research. We deem this worthwhile because a keyword-oriented bibliographical search reveals that less than 5% of the biofilm literature is devoted to methodology. In this report, we (i) summarize current methodologies for biofilm characterization, monitoring, and quantification; (ii) discuss advances in the discovery of effective imaging and sensing tools and modalities; (iii) provide an overview of tailored animal models that assess features of biofilm infections; and (iv) make recommendations defining the most appropriate methodological tools for clinical settings.

scholarly journals Microbial biofilm: a “sticky” problem

2018 ◽  
Vol 33 (1) ◽  
Author(s):  
Arianna Pompilio ◽  
Giovanni Di Bonaventura
Keyword(s):  
Biofilm Formation ◽  
Therapeutic Strategies ◽  
Review Article ◽  
Bacterial Biofilm ◽  
Formation Mechanisms ◽  
The Past ◽  
Underlying Mechanisms ◽  
Biofilm Development ◽  
Multispecies Biofilms

Bacteria can form, on virtually any surface, single- and multispecies biofilms intrinsically resistant/tolerant to antibiotics and elusive of the host immune response. The study of bacterial biofilm development has, therefore, received great interest over the past 20 years and is motivated by the well-recognized role of these multicellular communities in infectious diseases. In this review article, we provide a synopsis of (i) biofilm formation mechanisms; (ii) biofilm clinical significance and underlying mechanisms; (iii) the current methodologies for microbiological diagnosis of biofilm-related infections; and (iv) current and future therapeutic strategies to combat biofilm-associated infections.

Psychotropic Drugs in Somatic Disorders

1975 ◽  
Vol 6 (1-2) ◽  
pp. 267-282 ◽  
Author(s):  
Charles Solow
Keyword(s):  
Heart Disease ◽  
Ischemic Heart Disease ◽  
Clinical Investigation ◽  
Pulmonary Insufficiency ◽  
Gastrointestinal Disorders ◽  
Clinical Settings ◽  
Current Trends ◽  
Somatic Illness ◽  
Somatic Disorders ◽  
Theoretical Issues

Current trends in the employment of psychotropic medication in somatic illness are considered, and some of the theoretical issues raised by this practice are explored. While much further clinical investigation is needed, a review is made of currently available knowledge regarding psychopharmacotherapy in specific clinical settings: pain, delirium, ischemic heart disease, gastrointestinal disorders, dermatological illness, and in renal, hepatic and pulmonary insufficiency.

Periodontopathogens: a new view. Systematic review. Part 2

2020 ◽  
Vol 20 (2) ◽  
pp. 160-167
Author(s):  
E. S. Slazhneva ◽  
E. A. Tikhomirova ◽  
V. G. Atrushkevich
Keyword(s):  
Systematic Review ◽  
Periodontal Disease ◽  
Pathogenic Bacteria ◽  
Periodontal Diseases ◽  
Oral Microbiome ◽  
Controlled Trials ◽  
New Paradigm ◽  
Microbial Composition ◽  
Randomized Controlled ◽  
The Past

Relevance. The modern view of periodontitis as a dysbiotic disease that occurs as a result of changes in the microbial composition of the subgingival region is considered in a systematic review.Purpose. To study a new paradigm of development of generalized periodontitis.Materials and methods. Randomized controlled trials (RCTS) were selected for the study, including cluster RCTS, controlled (non-randomized) microbiological and clinical studies of the oral microbiome in adult patients with generalized periodontitis over the past 10 years.Results. The transition from a symbiotic microflora to a dysbiotic pathogenic community triggers the host's inflammatory response, which contributes to the development of periodontal diseases. Modern ideas about periodontal pathogenic bacteria dictate new requirements for the treatment of periodontal diseases. The second part of the review examines the microbial profiles of periodontal disease in various nosological forms, the mechanisms of the immune response and approaches to the treatment of periodontal disease from the perspective of biofilm infection.Conclusions. As follows from modern literature periodontitis is to a certain extent caused by the transition from a harmonious symbiotic bacterial community to a dysbiotic one. Recent scientific studies have shown that not single microorganism is not able to cause disease but the microbial community as a whole leads to the development of pathology.

Bifunctional Composites for Biofilms Modulation on Cervical Restorations

2021 ◽  
pp. 002203452110181
Author(s):  
A.A. Balhaddad ◽  
I.M. Garcia ◽  
L. Mokeem ◽  
M.S. Ibrahim ◽  
F.M. Collares ◽  
...  
Keyword(s):  
Free Energy ◽  
Surface Free Energy ◽  
Contact Angles ◽  
Bacterial Biofilm ◽  
Dental Composite ◽  
Log P ◽  
Rrna Gene ◽  
Cervical Lesions ◽  
Biofilm Growth ◽  
Biofilm Development

Cervical composites treating root carious and noncarious cervical lesions usually extend subgingivally. The subgingival margins of composites present poor plaque control, enhanced biofilm accumulation, and cause gingival irritation. A potential material to restore such lesions should combine agents that interfere with bacterial biofilm development and respond to acidic conditions. Here, we explore the use of new bioresponsive bifunctional dental composites against mature microcosm biofilms derived from subgingival plaque samples. The designed formulations contain 2 bioactive agents: dimethylaminohexadecyl methacrylate (DMAHDM) at 3 to 5 wt.% and 20 wt.% nanosized amorphous calcium phosphate (NACP) in a base resin. Composites with no DMAHDM and NACP were used as controls. The newly formulated 5% DMAHDM–20% NACP composite was analyzed by micro-Raman spectroscopy and transmission electron microscopy. The wettability and surface-free energy were also assessed. The inhibitory effect on the in vitro biofilm growth and the 16S rRNA gene sequencing of survival bacterial colonies derived from the composites were analyzed. Whole-biofilm metabolic activity, polysaccharide production, and live/dead images of the biofilm grown over the composites complement the microbiological assays. Overall, the designed formulations had higher contact angles with water and lower surface-free energy compared to the commercial control. The DMAHDM-NACP composites significantly inhibited the growth of total microorganisms, Porphyromonas gingivalis, Prevotella intermedia/nigrescens, Aggregatibacter actinomycetemcomitans, and Fusobacterium nucleatum by 3 to 5-log ( P < 0.001). For the colony isolates from control composites, the composition was typically dominated by the genera Veillonella, Fusobacterium, Streptococcus, Eikenella, and Leptotrichia, while Fusobacterium and Veillonella dominated the 5% DMAHDM–20% NACP composites. The DMAHDM-NACP composites contributed to over 80% of reduction in metabolic and polysaccharide activity. The suppression effect on plaque biofilms suggested that DMAHDM-NACP composites might be used as a bioactive material for cervical restorations. These results may propose an exciting path to prevent biofilm growth and improve dental composite restorations’ life span.

The Role of Histones and Heparin in Sepsis: A Review

2021 ◽  
pp. 088506662199232
Author(s):  
Xiaojuan Zhang ◽  
Xin Li
Keyword(s):  
Septic Shock ◽  
Multiple Organ ◽  
Clinical Settings ◽  
The Past ◽  
Life Saving ◽  
Extracellular Histones ◽  
Sepsis And Septic Shock ◽  
Development And Management ◽  
Made In

Septic shock with multiple organ failure is a devastating situation in clinical settings. Through the past decades, much progress has been made in the management of sepsis and its underlying pathogenesis, but a highly effective therapeutic has not been developed. Recently, macromolecules such as histones have been targeted in the treatment of sepsis. Histones primarily function as chromosomal organizers to pack DNA and regulate its transcription through epigenetic mechanisms. However, a growing body of research has shown that histone family members can also exert cellular toxicity once they relocate from the nucleus into the extracellular space. Heparin, a commonly used anti-coagulant, has been shown to possess life-saving capabilities for septic patients, but the potential interplay between heparin and extracellular histones has not been investigated. In this review, we summarize the pathogenic roles of extracellular histones and the therapeutic roles of heparin in the development and management of sepsis and septic shock.

The J. C. Richardson Lecture: Prospects for Canadian Medical Neurology

1975 ◽  
Vol 2 (2) ◽  
pp. 101-107 ◽  
Author(s):  
D.W. Baxter
Keyword(s):  
Clinical Investigation ◽  
Postgraduate Education ◽  
High Standard ◽  
Undergraduate Curriculum ◽  
Influential Factors ◽  
Work Patterns ◽  
Consultation Service ◽  
The Past ◽  
Fundamental Research

In 1975, medical neurology is a well established, viable, growing specialty in Canada. There are now almost 250 neurologists scattered across the country, congregated largely in the hospitals associated with our 16 medical schools. Neurology is a major component of the undergraduate curriculum in each of these schools, and the majority of schools are approved for postgraduate training in our specialty. The Royal College has certified an average of 18 new neurologists each year for the past five years. In our hospitals we work closely with our internist and neurosurgical colleagues and we receive the support of highly competent teams of neuropathologists, clinical electrophysiologists and neuroradiologists. We believe that we provide a generally high standard of consultation service to our medical and surgical colleagues. We accept direct responsibility for patients suffering from a host of acute neurological problems, but we accept long term responsibility for very few. We do a great deal of teaching at both the undergraduate and graduate levels. In fact, the major role which neurology plays in undergraduate curricula, and the stimulus of postgraduate education, probably have been the two most influential factors shaping the number, work patterns and distribution of Canadian neurologists. Many of us are engaged in clinical investigation, but relatively few medical neurologists in Canada make fundamental research contributions.

scholarly journals Repurposing Napabucasin as an Antimicrobial Agent against Oral Streptococcal Biofilms

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Xinyi Kuang ◽  
Tao Yang ◽  
Chenzi Zhang ◽  
Xian Peng ◽  
Yuan Ju ◽  
...  
Keyword(s):  
Dental Caries ◽  
Laser Scanning ◽  
Antibacterial Activities ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Oral Streptococci ◽  
Oral Keratinocytes ◽  
Microbial Composition ◽  
Biofilm Inhibition ◽  
Multispecies Biofilms

Objectives. Disruption of microbial biofilms is an effective way to control dental caries. Drug resistance and side effects of the existing antimicrobials necessitate the development of novel antibacterial agents. The current study was aimed at investigating the antibacterial activities of the repurposed natural compound napabucasin against oral streptococci. Methods. The minimum inhibitory concentration, minimum bactericidal concentration, minimum biofilm inhibition concentration, and minimum biofilm reduction concentration of Streptococcus mutans, Streptococcus gordonii, and Streptococcus sanguinis were examined by a microdilution method. Cytotoxicity of napabucasin against human oral keratinocytes, human gingival epithelia, and macrophage RAW264.7 was evaluated by CCK8 assays. The dead/live bacterium and exopolysaccharide in the napabucasin-treated multispecies biofilms were evaluated by confocal laser scanning microscopy. Microbial composition within the napabucasin-treated biofilms was further visualized by fluorescent in situ hybridization and qPCR. And the cariogenicity of napabucasin-treated biofilms was evaluated by transverse microradiography. Results. Napabucasin exhibited good antimicrobial activity against oral streptococcal planktonic cultures and biofilms but with lessened cytotoxicity as compared to chlorhexidine. Napabucasin reduced the cariogenic S. mutans and increased the proportion of the commensal S. gordonii in the multispecies biofilms. More importantly, napabucasin significantly reduced the demineralization capability of biofilms on tooth enamels. Conclusion. Napabucasin shows lessened cytotoxicity and comparable antimicrobial effects to chlorhexidine. Repurposing napabucasin may represent a promising adjuvant for the management of dental caries.

“Economics in Command?” Ideology and Policy Since the Third Plenum, 1978–1984

1984 ◽  
Vol 99 ◽  
pp. 417-461 ◽  
Author(s):  
Stuart R. Schram
Keyword(s):  
Policy Making ◽  
Question Mark ◽  
The Third ◽  
The Past ◽  
Great Leap ◽  
Current Trends

In this article, I shall attempt to give an overview of the most important political and ideological developments during the past six years, and in this context, to assess current trends in China. The three-word title is, of course, deliberately modelled on the Great Leap slogan “Politics in command”, and is intended to evoke the problem of whether or not policy-making since 1978 has been largely shaged by economic realities, and/or by the economic goals of the, leadership I have placed a question mark after it because, though I shall certainly express some opinions on this topic before I have done, I doubt that the issue can as yet be regarded as finally settled.

scholarly journals Current Trends in Dental Composites

1995 ◽  
Vol 6 (4) ◽  
pp. 302-318 ◽  
Author(s):  
J.L. Ferracane
Keyword(s):  
Wear Resistance ◽  
Clinical Performance ◽  
Color Stability ◽  
Dental Composites ◽  
Filler Materials ◽  
Posterior Teeth ◽  
The Past ◽  
Current Trends ◽  
Dentin Adhesives ◽  
High Concentrations

The clinical performance of dental composites has been significantly improved over the past decade through modifications in formulation that include: using more stable polymerization promoters for greater color stability; incorporating high concentrations of finely ground fillers to produce adequate strength and excellent wear resistance while retaining translucency ; adding radiopacifying agents for improved diagnostics; and utilizing dentin adhesives. However, there are problems which limit the use of composites, especially in posterior teeth. The materials remain very technique-sensitive, due to the extensive contraction which accompanies polymerization and negatively influences marginal sealing. In addition, the materials are generally considered to have inadequate mechanical properties and wear resistance in contact areas to serve as total replacements for amalgams. Current efforts are focusing on several areas, including the development of non- or minimally-shrinking dental composites containing spiro-orthocarbonates as additives to dimethacrylates or epoxy-base resins, and the production of alternative filler materials for ideal wear resistance and esthetics. This paper reviews the composition and characteristics of current dental composites, as well as recent areas of study.

Sign in / Sign up

Export Citation Format

Share Document