scholarly journals Unraveling the Etiology of Periodontitis

2021 ◽  
Vol 4 (1) ◽  
pp. 1-4
Author(s):  
Dr. Zeenat Iqbal ◽  
◽  
Mohd. Aamir Mirza
Keyword(s):  
Antimicrobial Resistance ◽  
Anaerobic Bacteria ◽  
Personal Hygiene ◽  
Treatment Modalities ◽  
Tooth Surface ◽  
Ecological Niches ◽  
High Dose ◽  
Periodontal Pathogens ◽  
Facultative Anaerobic Bacteria ◽  
Micro Organisms

Across the globe, incidence of oral afflictions like gingivitis and periodontitis are increasing at a very fast pace. Evidencearethere to support the fact that despite of being an oro-dental infection, periodontitis is associated with the systemic diseases too. Different ecological niches of oral cavity can harbor both pathogenic and non-pathogenic micro-organisms. Although the main cause of the disease is the anaerobic or the facultative anaerobic bacteria, other factors such as poor personal hygiene, diet and immune related disorders are also responsible for the progression of the disease. The vicious circle starts from deposition of the bacterial plaque/biofilm on the tooth surface then leading to gingivitis. If left untreated, it progresses to the development of periodontal pockets and ultimately tooth loss. However traditional treatment modalities like high dose of systemic antibiotics are available but antimicrobial resistance and virulence of the periodontal pathogens is the major cause of the treatment failures. This review primarily focuses on the etiology, pathogenesis and microbiology of the periodontitis. It also discusses the virulence and antimicrobial resistance factors of the periodontopathic micro-organisms. It is an attempt to develop the thorough understanding of the disease so that better therapeutic outcomes of periodonto-therapy can be attained.

The Role of Facultative Anaerobic Micro-Organisms in Anaerobic Biodegradation of Chlorophenols

1985 ◽  
Vol 17 (1) ◽  
pp. 289-301 ◽  
Author(s):  
R Hakulinen ◽  
S Woods ◽  
J Ferguson ◽  
M Benjamin
Keyword(s):  
Anaerobic Bacteria ◽  
Experimental Period ◽  
Common Species ◽  
Methanogenic Bacteria ◽  
Mixed Cultures ◽  
Synthetic Wastewater ◽  
Anaerobic Conditions ◽  
Facultative Anaerobic ◽  
Facultative Anaerobic Bacteria ◽  
Micro Organisms

Pure cultures of facultative anaerobic bacteria and yeasts were isolated from anaerobic reactors fed synthetic wastewater which contained eight different chlorophenolic compounds. The concentration of facultative anaerobic micro-organisms was followed in the reactor throughout the experimental period, during which the chlorophenol concentrations were increased and many of the chloronated phenols were removed nearly completely. The most common species were Klebsiella spp. and K. Pneumoniae. Some of the common colonies were tentatively identified as Pseudomonas-like organisms and Aeromonas hydrofila. Methanogenic bacteria in the reactor were mainly acetate users. When the total chlorophenol concentration in the feed was increased from zero to 2.4 or 5.3 mg/1, the concentration of Pseudomonas-like organisms increased, as did the concentration of yeasts. Pure and mixed cultures were tested for use of 2,4,6-trichlorophenol (246-TCP) as a sole carbon and energy source under anaerobic conditions. None of the isolates were able to degrade 246-TCP under anaerobic conditions in pure culture. However, mixed cultures containing only P. aeruginosa and K. oxytoca were able to degrade 246-TCP.

STRUCTURE AND DYNAMICS OF ENVIRONMENTAL PARAMETERS OF HUMAN INTESTINAL MICROBIOME IN DIFFERENT CLIMATIC AND ECOLOGICAL ZONES OF ST. PETERSBURG

2020 ◽  
pp. 31-36
Author(s):  
Bugero N.V. ◽  
Ilyina N.A. ◽  
Aleksandrova S.M.
Keyword(s):  
Environmental Parameters ◽  
Intestinal Microbiome ◽  
Ecological Niches ◽  
Horizontal Structure ◽  
Ecological Zones ◽  
Qualitative And Quantitative ◽  
Symbiotic Relationships ◽  
Structure And Dynamics ◽  
Quantitative Changes ◽  
Micro Organisms

In order to understand the structure and dynamics of symbiotic relationships of human intestinal biotope micro-organisms, taxonomic constancy indices, the degree of contagion of the biocenosis under study and floristic significance were investigated, which made it possible to detect qualitative and quantitative changes in the microecology of the biotope being studied in persons living in different ecologically heterogeneous territories of Saint Petersburg. The contagiosity index estimated the distribution of species in space. Persons living in the ecologically disadvantaged Kirov district of the city have been found to show a reliable increase in this indicator for the obligate microflora: bifido and lacto bacteria, intestinal columns and bacteroids, compared to the resort district, which is considered a relatively favourable area for residence. On the contrary, there has been a reliable decrease in this indicator in the group of opportunistic micro-organisms (fungi of the genus Candida, staphylococcus, clostridium, etc.), resulting in the liberation of ecological niches successfully occupied by transient flora. This ratio reveals an imbalance of participation in the horizontal structure of the intestine ecosystem of the main symbiotes and representatives of the transient flora. To analyse the structure of symbiotic relationships, the constancy indices that form the microflora of the individuals of the groups studied were investigated. The analysis of the data obtained suggested that the dominant species in both groups were optional-anaerobic bifido and lactobacteria and oblique-anaerobic bacteroids. It should be noted, however, that in the residents of the dysfunctional Kirovsky district, against the background of the reduced constancy of the normal flora, opportunistic micro-organisms have entered. The floral significance index was also declining in the obligate flora of this group and increased for opportunistic species. Thus, the study of the environmental characteristics of the intestinal biotope using different ecological parameters for persons living in different technogenic load regions of St. Petersburg has shown that in the Kirov district with an unfavourable environmental situation there are compensated qualitative and quantitative changes in the intestinal microbiocenosis, resulting in a change in the hierarchy in the overall structure of micro-organisms.

CHANGES IN SMALL INTESTINE MICROFLORA IN PATIENTS WITH ACUTE INTESTINAL OBSTRUCTION

2020 ◽  
pp. 16-18
Author(s):  
V. M. Lykhman ◽  
O. M. Shevchenko ◽  
Ye. O. Bilodid ◽  
Igor Vladimirovich Volchenko ◽  
I. A. Kulyk ◽  
...  
Keyword(s):  
Small Intestine ◽  
Gastrointestinal Tract ◽  
Species Composition ◽  
Intestinal Obstruction ◽  
Bacterial Flora ◽  
Anaerobic Bacteria ◽  
Acute Intestinal Obstruction ◽  
Gram Positive ◽  
Mechanical Intestinal Obstruction ◽  
Facultative Anaerobic Bacteria

Among urgent surgical diseases of abdominal cavity, an acute intestinal obstruction is the most difficult to be diagnosed and treated. Leading factor, determining the development of pathophysiological processes is considered to be the progressive manifestations of enteric insufficiency syndrome, resulting in intestinal barrier impairment, negative changes in ecology of intestinal flora, increased endotoxins. To identify the small intestine microflora in acute intestinal obstruction and determine the role of dysbiotic disorders in clinical manifestations of main pathological process, a study was conducted in 60 patients with mechanical intestinal obstruction. The small intestine has a relatively rare microflora, consisting mainly of gram−positive facultative aerobic microorganisms, streptococci, lactobacilli. The distal ileum in nearly 30−55 % of healthy people contains scanty microflora, and yet the flora of this area differs from the microbial population of the higher gastrointestinal tract due to higher concentration of gram−negative bacteria. Optional−anaerobic coliform bacilli, anaerobic bifidobacteria and fusobacteria, bacteroids, the number of which starts exceeding the one of gram−positive species, are presented in significant quantities. Distal to the ileocecal valve there are significant changes in the microflora quantitative and species composition. Obligatory anaerobic bacteria become the predominant part of microflora, exceeding the number of aerobic and facultative anaerobic bacteria. The bacterial flora in different parts of gastrointestinal tract has its own specifics and is quite constant, as a result of the interaction of many factors, regulating the bacterial population in small intestine. The most important among them are: acidity of gastric juice, normal peristaltic activity of the intestine, bacterial interactions and immune mechanisms. Disorders of the intestine motor and evacuation function with its obstruction lead to slow passage of the chyme and contamination of the upper gastrointestinal tract with new types of microbes. There is a syndrome of small intestine excessive colonization, which means an increased concentration of bacterial populations in it, similar in species composition to the colon microflora. Pathological intra−intestinal contents become a source of endogenous infection and re−infection of the patient, leads to internal digestive disorders, which is manifested by syndrome of malabsorption of proteins, carbohydrates and vitamins. Key words: acute intestinal obstruction, small intestinal microflora, conditionally pathogenic microorganisms, intestinal biocenosis.

scholarly journals Colonocyte metabolism shapes the gut microbiota

Science ◽  
2018 ◽  
Vol 362 (6418) ◽  
pp. eaat9076 ◽  
Author(s):  
Yael Litvak ◽  
Mariana X. Byndloss ◽  
Andreas J. Bäumler
Keyword(s):  
Gut Microbiota ◽  
Anaerobic Bacteria ◽  
Enteric Pathogens ◽  
Metabolic Reprogramming ◽  
Human Diseases ◽  
Fermentation Products ◽  
Colonic Microbiota ◽  
Obligate Anaerobic ◽  
Control Switch ◽  
Facultative Anaerobic Bacteria

An imbalance in the colonic microbiota might underlie many human diseases, but the mechanisms that maintain homeostasis remain elusive. Recent insights suggest that colonocyte metabolism functions as a control switch, mediating a shift between homeostatic and dysbiotic communities. During homeostasis, colonocyte metabolism is directed toward oxidative phosphorylation, resulting in high epithelial oxygen consumption. The consequent epithelial hypoxia helps to maintain a microbial community dominated by obligate anaerobic bacteria, which provide benefit by converting fiber into fermentation products absorbed by the host. Conditions that alter the metabolism of the colonic epithelium increase epithelial oxygenation, thereby driving an expansion of facultative anaerobic bacteria, a hallmark of dysbiosis in the colon. Enteric pathogens subvert colonocyte metabolism to escape niche protection conferred by the gut microbiota. The reverse strategy, a metabolic reprogramming to restore colonocyte hypoxia, represents a promising new therapeutic approach for rebalancing the colonic microbiota in a broad spectrum of human diseases.

scholarly journals Indications of Peptide Receptor Radionuclide Therapy (PRRT) in Gastroenteropancreatic and Pulmonary Neuroendocrine Tumors: An Updated Review

2021 ◽  
Vol 10 (6) ◽  
pp. 1267
Author(s):  
Baptiste Camus ◽  
Anne-Ségolène Cottereau ◽  
Lola-Jade Palmieri ◽  
Solène Dermine ◽  
Florence Tenenbaum ◽  
...  
Keyword(s):  
Neuroendocrine Tumors ◽  
Radionuclide Therapy ◽  
Somatostatin Receptors ◽  
Peptide Receptor Radionuclide Therapy ◽  
Phase Iii ◽  
Treatment Modalities ◽  
High Dose ◽  
Double Dose ◽  
Peptide Receptor ◽  
Phase Iii Study

Radionuclide therapy for neuroendocrine tumors is a form of systemic radiotherapy that allows the administration of targeted radionuclides into tumor cells that express a large quantity of somatostatin receptors. The two most commonly used radio-peptides for radionuclide therapy in neuroendocrine tumors are 90Y-DOTATOC and 177Lu-DOTATATE. Radio-peptides have been used for several years in the treatment of advanced neuroendocrine tumors. Recently, the randomized Phase III study NETTER-1 compared177Lu-DOTATATE versus high-dose (double-dose) octreotide LAR in patients with metastatic midgut neuroendocrine tumors, and demonstrated its efficacy in this setting. Strong signals in favor of efficiency seem to exist for other tumors, in particular for pancreatic and pulmonary neuroendocrine tumors. This focus on radionuclide therapy in gastroenteropancreatic and pulmonary neuroendocrine tumors addresses the treatment modalities, the validated and potential indications, and the safety of the therapy.

Effects of antibiotics on the development and intestinal bacterial diversity of black soldier fly larvae

2021 ◽  
pp. 1-14
Author(s):  
J.B. Zhang ◽  
Y. Meng ◽  
J. Xu ◽  
C. Rensing ◽  
D. Wang
Keyword(s):  
Bacterial Diversity ◽  
Larval Growth ◽  
Anaerobic Bacteria ◽  
Inhibitory Effect ◽  
High Dose ◽  
Streptomycin Sulphate ◽  
Black Soldier Fly ◽  
Operational Taxonomic Units ◽  
Black Soldier Fly Larvae ◽  
Hermetia Illucens Larvae

The effects of four antibiotics (metronidazole (M) levofloxacin (L), sodium ampicillin (A), and streptomycin sulphate (S)) and their pair-wise combinations at three doses on the development and intestinal bacterial diversity of the black soldier fly (BSF; Hermetia illucens) larvae were studied. At a low dose M and L were able to inhibit larval growth. At a high dose, all antibiotics were shown to inhibit larval growth. However, the pair-wise combinational use of the antibiotics did not effectively enhance the inhibitory effect. The gut bacterial diversity of the normal control (NC) was significantly higher than the antibiotic-treated groups with 737 operational taxonomic units (OTUs) from the larval guts of NC, compared to 305 and 227 from ML and AS. The number of anaerobic bacteria in ML was significantly lower than in NC and AS, with the relative abundance of OTUs from larval guts of ML being only about 0.01, compared to 0.4 for NC and 0.15 for AS. These results indicated that antibiotics at the experimental concentration did not affect the palatability of food for insects, but they would affect the diversity of food and intestinal microorganisms of BSF larvae, and the inhibitory effect of antibiotics on growth and development of BSF larvae displayed in this study was a complex effect.

scholarly journals De Novo Collapsing Glomerulopathy: An Unusual Cause of Early Graft Failure following Kidney Transplantation

2011 ◽  
Vol 2011 ◽  
pp. 1-3 ◽  
Author(s):  
Kalathil K. Sureshkumar ◽  
Imran Dosani ◽  
Katherine M. Jasnosz ◽  
Swati Arora
Keyword(s):  
Renal Failure ◽  
De Novo ◽  
Clinical Manifestations ◽  
Deceased Donor ◽  
Treatment Modalities ◽  
High Dose ◽  
Collapsing Glomerulopathy ◽  
Early Graft ◽  
Rapidly Progressive Renal Failure ◽  
Deceased Donor Kidney Transplant

Collapsing glomerulopathy (CG) is a variant of focal segmental glomerulosclerosis (FSGS) characterized histologically by prominent glomerular capillary tuft collapse with hypertrophy and hyperplasia of podocytes and tubulointerstitial damage. Patients usually present with heavy proteinuria and rapidly progressive renal failure. We report a patient who developed de novo CG with severe clinical manifestations including worsening renal failure and nephrotic syndrome within six months of receiving deceased donor kidney transplant. Secondary work-up was negative, and despite therapy with high-dose steroids and plasmapheresis, allograft function rapidly deteriorated with the need for dialysis. Theories about the pathogenesis of this entity as well as treatment modalities are discussed.

scholarly journals Streptomycin-Induced Inflammation Enhances Escherichia coli Gut Colonization Through Nitrate Respiration

mBio ◽  
2013 ◽  
Vol 4 (4) ◽  
Author(s):  
Alanna M. Spees ◽  
Tamding Wangdi ◽  
Christopher A. Lopez ◽  
Dawn D. Kingsbury ◽  
Mariana N. Xavier ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Microbial Community ◽  
Intestinal Inflammation ◽  
Anaerobic Bacteria ◽  
Nitrate Respiration ◽  
Colonization Resistance ◽  
Content Type ◽  
E Coli ◽  
Gut Colonization ◽  
Facultative Anaerobic Bacteria

ABSTRACTTreatment with streptomycin enhances the growth of human commensalEscherichia coliisolates in the mouse intestine, suggesting that the resident microbial community (microbiota) can inhibit the growth of invading microbes, a phenomenon known as “colonization resistance.” However, the precise mechanisms by which streptomycin treatment lowers colonization resistance remain obscure. Here we show that streptomycin treatment rendered mice more susceptible to the development of chemically induced colitis, raising the possibility that the antibiotic might lower colonization resistance by changing mucosal immune responses rather than by preventing microbe-microbe interactions. Investigation of the underlying mechanism revealed a mild inflammatory infiltrate in the cecal mucosa of streptomycin-treated mice, which was accompanied by elevated expression ofNos2, the gene that encodes inducible nitric oxide synthase. In turn, this inflammatory response enhanced the luminal growth ofE. coliby nitrate respiration in aNos2-dependent fashion. These data identify low-level intestinal inflammation as one of the factors responsible for the loss of resistance toE. colicolonization after streptomycin treatment.IMPORTANCEOur intestine is host to a complex microbial community that confers benefits by educating the immune system and providing niche protection. Perturbation of intestinal communities by streptomycin treatment lowers “colonization resistance” through unknown mechanisms. Here we show that streptomycin increases the inflammatory tone of the intestinal mucosa, thereby making the bowel more susceptible to dextran sulfate sodium treatment and boosting theNos2-dependent growth of commensalEscherichia coliby nitrate respiration. These data point to the generation of alternative electron acceptors as a by-product of the inflammatory host response as an important factor responsible for lowering resistance to colonization by facultative anaerobic bacteria such asE. coli.

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