scholarly journals Migration of aerobic bacteria from the duodenum to the pancreas with tumors: a mechanistic understanding

Author(s):  
Hiroaki Shirai ◽  
Cocoro Ito ◽  
Kosuke Tsukada

Abstract More aerobic bacteria are found in the pancreas with tumors than in the healthy pancreas. We provide a mechanistic understanding of the migration of intestinal bacteria from the duodenum to the pancreas with tumors. Mathematical models of migration of aerobic bacteria from the duodenum to the pancreas with tumors in the hepatopancreatic duct were developed. In addition, the behaviors of GFP E. coli under a pH gradient in a microfluidic device were analyzed. Moreover, upstream migrations of Pseudomonas fluorescens against flow were measured in a polydimethylsiloxane (PDMS) T-shaped cylinder mimicking a pancreatic duct. The simulated bacterial concentration of the pancreas with tumors was higher than that of the healthy pancreas and agreed reasonably well with the literature. Migration of aerobic bacteria in the hepatopancreatic duct is counteracted by bile and pancreatic juice flow but facilitated greatly by bacterial pH taxis from lower pH in duodenum fluid toward slightly alkaline pH in pancreatic juice, favorable for them. Migration of bacteria to the pancreas with tumors is made easier by solid tumors on the pancreatic duct, which compresses the pancreatic duct and thus reduces the fluid flow rate. On the other hand, GFP E. coli migrated under the pH gradient in a microfluidic device from acidic areas toward neutral or slightly alkaline pH, validating pH taxis. Furthermore, Pseudomonas fluorescens migrated upstream from hydrochloride solution but not from bicarbonate solution against bicarbonate flow at >20 µm/s, with an advancing velocity of approximately 60 µm/s, validating the models (244 words).

2009 ◽  
Vol 72 (4) ◽  
pp. 856-859 ◽  
Author(s):  
HOIKYUNG KIM ◽  
YOUNGJUN LEE ◽  
LARRY R. BEUCHAT ◽  
BONG-JUNE YOON ◽  
JEE-HOON RYU

Sprouted vegetable seeds used as food have been implicated as sources of outbreaks of Salmonella and Escherichia coli O157:H7 infections. We profiled the microbiological quality of sprouts and seeds sold at retail shops in Seoul, Korea. Ninety samples of radish sprouts and mixed sprouts purchased at department stores, supermarkets, and traditional markets and 96 samples of radish, alfalfa, and turnip seeds purchased from online stores were analyzed to determine the number of total aerobic bacteria (TAB) and molds or yeasts (MY) and the incidence of Salmonella, E. coli O157:H7, and Enterobacter sakazakii. Significantly higher numbers of TAB (7.52 log CFU/g) and MY (7.36 log CFU/g) were present on mixed sprouts than on radish sprouts (6.97 and 6.50 CFU/g, respectively). Populations of TAB and MY on the sprouts were not significantly affected by location of purchase. Radish seeds contained TAB and MY populations of 4.08 and 2.42 log CFU/g, respectively, whereas populations of TAB were only 2.54 to 2.84 log CFU/g and populations of MY were 0.82 to 1.69 log CFU/g on alfalfa and turnip seeds, respectively. Salmonella and E. coli O157:H7 were not detected on any of the sprout and seed samples tested. E. sakazakii was not found on seeds, but 13.3% of the mixed sprout samples contained this potentially pathogenic bacterium.


2020 ◽  
Vol 08 (12) ◽  
pp. E1765-E1768
Author(s):  
Ryoko Shimizuguchi ◽  
Masataka Kikuyama ◽  
Terumi Kamisawa ◽  
Sawako Kuruma ◽  
Kazuro Chiba

Abstract Background and study aims Acute obstructive suppurative pancreatic ductitis (AOSPD) is a suppurative pancreatic duct infection with main pancreatic duct (MPD) or accessory pancreatic duct obstruction in the absence of a pancreatic pseudocyst or necrosis, which is experienced usually in chronic pancreatitis. The diagnosis is confirmed by the finding of pancreatic duct obstruction on endoscopic retrograde cholangiopancreatography (ERCP) with evidence of infection, such as a positive pancreatic juice culture or drainage of purulent pancreatic juice. Patients and methods We studied five patients with pancreatic ductal adenocarcinoma (PDAC) and one with chronic myelogenous leukemia (CML), who suffered from AOSPD. Results Of the 281 PDAC and 39 CML patients who we treated in the past 2 years in our hospital, five with PDAC (1.8 %) and one with CML (2.6 %) experienced AOSPD. Each patient had fever, abdominal pain, and increased blood C-reactive protein. Pancreatography found that each patient had a MPD stricture and an upstream dilatation. Four had a disruption of the MPD in the upper stream of the stricture. Nasopancreatic drainage was successfully performed in all patients. Pancreatic juice culture was positive for Klebsiella pneumonia, Enterobacter agerogenes, or Enterococcus cloacae in four patients. Conclusion AOSPD should be considered in pancreatic malignancy with fever and abdominal pain. Prompt diagnosis of AOSPD could avoid shortening of survival of patients with an already poor prognosis by infection.


2021 ◽  
Author(s):  
Sarka Klementova ◽  
Martina Poncarová ◽  
Helena Langhansová ◽  
Jaroslava Lieskovská ◽  
David Kahoun ◽  
...  

Abstract Photochemical degradation of fluoroquinolones ciprofloxacin, enrofloxacin and norfloxacin in aqueous solution under light conditions relevant to surface waters at neutral and alkaline pH was found to proceed readily with half-lives between 0.9 and 2.7 min. The products of photochemical degradation identified by HPLC-MS included defluorinated, hydroxylated, and decarboxylated structures as well as structures with opened cyclic structures. For all of the studied substances, the reaction pathways were influenced significantly by the pH of the reaction system, with more products formed at alkaline pH than at neutral pH: the ratios of products in neutral and alkaline pH were 16/26, 9/19, 15/23 for ciprofloxacin, enrofloxacin, and norfloxacin, respectively. The structures of photoproducts and pathways of photochemical degradation are proposed. The antibacterial activities of photoproduct mixtures tested on E. coli and S. epidermidis were significantly higher in comparison to parental antibiotics in the case of both ciprofloxacin and enrofloxacin with p-values less than 0.0001 in most cases. The effect of the photoproducts was shown to be dependent on the pH value of the original antibiotic solutions before photodegradation: for ciprofloxacin, antibacterial activity against E. coli was more notably pronounced with regard to neutral pH photoproducts, while a less significant, or in one case not significant, effect of pH was observed against S. epidermidis ; for norfloxacin, antibacterial activity against both E. coli and S. epidermidis were especially high with regard to alkaline pH photoproducts


2021 ◽  
Vol 2021 ◽  
pp. 1-5
Author(s):  
Emmanuelle Guérin ◽  
Paule Poirier ◽  
Marine Nervo ◽  
Christophe Le Terrier

Because of its characteristic features of autoinfection, the parasitic nematode Strongyloides stercoralis can infect patients for years. An acceleration of its autoinfective cycle can be triggered by human T-lymphotropic virus-1 (HTLV-1) infection, mainly by the deviation of the protective Th2- to Th1-type immune response and can lead to severe disease by dissemination of Strongyloides stercoralis larvae carrying intestinal bacteria to multiple organs. Meningitis caused by enteric Gram-negative bacteria is a potentially fatal complication of disseminated strongyloidiasis. Herein, we present the case of a Strongyloides-HTLV-1 coinfected patient, admitted for E. coli meningitis. One day after initiation of ivermectin, the patient developed significant S. stercoralis dissemination, complicated by multiorgan failure syndrome, and died from neurological failure. While the initial clinical scenario of our case has already been well described in the literature, its course after antihelminthic treatment initiation remains unclear and needs to be discussed.


2019 ◽  
Vol 41 (3) ◽  
Author(s):  
Pham Hoang Long ◽  
Nguyen Hoai Chau ◽  
Nguyen Chi Thanh ◽  
Ngo Quoc Buu

This research aims to study on the disinfection efficiency of Hoa Sen medical instrument sterilizing equipment based on the application of ECA technology at General Hospital and Obstetrics and Paediatrics Hospitals in Tra Vinh. Disinfection using ECA technology is a method that does not require the introduction of special oxidizing agents except of water and salt. ECA solution - Anolyte solution has very strong oxidants, which oxidize components such as protein, lipid, etc. (usually of the bacterial cell membrane) that make the cell membrane decomposed, reducing 77−93% of the respiratory ability of bacterial cells, weakening them and eventually being destroyed. Hoa Sen medical instrument sterilizing equipment has a similar construction form as a regular double washing table with two wash basins, wherein one sink with a faucet which produces purified water, while other one has a faucet that gives anolyte solution for sterilization. Both faucets are based on a touch support. At the bottom of the sink an anolyte solution production system was installed. Valorization of the disinfection ability of the Hoa Sen medical instrument sterilizing equipment was based on the determination of the number of microorganisms on the surface of the instrument before and after being soaked with an antiseptic washing table. Microbiological criteria are the number of aerobic bacteria, E. Coli and Coliforms. Analytical samples were quantified by culture method on agar plates. Analysis of total aerobic bacteria, E. Coli and Coliforms bacteria according to Vietnam Standard TCVN 4884:2015, TCVN 6846:2007 and TCVN 6848:2007, respectively. The results showed that bacterial removal efficiency was elevated with a novel Hoa Sen sterilizing equipment anolyte. In laboratory scale, E. Coli and Coliforms bacteria with a density of 105 CFU/mL were completely removed in 30 sec contact with an anolyte solution of 300 mg/L active chlorine concentration. In hospital scale, the removal efficiency of total aerobic bacteria on the surface of medical instruments after surgery was 99% for one minute disinfection time. For E. Coli and Coliforms bacteria, the results of the analysis were not detected in both cases before and after sterilization. 


2008 ◽  
Vol 11 (16) ◽  
pp. 2001-2006 ◽  
Author(s):  
M. Haghighati ◽  
M.R. Mofid ◽  
M.K. Nekouei ◽  
P. Yaghmaei ◽  
A.H. Tafreshi

1996 ◽  
Vol 59 (6) ◽  
pp. 666-669 ◽  
Author(s):  
C. O. GILL ◽  
M. BADONI ◽  
T. JONES

Swab samples were obtained from the surfaces of randomly selected beef carcasses passing through a high-speed dressing process. A single sample was obtained from a randomly selected site on the surface of each selected carcass. Fifty such samples were collected at each of four stages in the process. The aerobic bacteria, coliforms, and Escherichia coli recovered from each sample were enumerated. Values for the mean log units and standard deviations of each set of 50 log values were calculated on the assumption that the log values were normally distributed. The log of the arithmetic mean was estimated from the mean log and standard deviation values for each set. The results show that the average numbers of E. coli, coliforms, and aerobic bacteria which are deposited on carcasses during skinning and evisceration are not reduced by trimming, and that washing approximately halves the average numbers of those bacteria on carcasses. It is concluded that commercial trimming and washing operations are not effective means of decontaminating beef carcasses.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Samuel Miller ◽  
Alison A. Weiss ◽  
William R. Heineman ◽  
Rupak K. Banerjee

Abstract The presence of bacterial pathogens in water can lead to severe complications such as infection and food poisoning. This research proposes a point-of-care electroosmotic flow driven microfluidic device for rapid isolation and detection of E. coli in buffered solution (phosphate buffered saline solution). Fluorescent E. coli bound to magnetic microbeads were driven through the microfluidic device using both constant forward flow and periodic flow switching at concentrations ranging from 2 × 105 to 4 × 107 bacteria/mL. A calibration curve of fluorescent intensity as a function of bacteria concentration was created using both constant and switching flow, showing an increase in captured fluorescent pixel count as concentration increases. In addition, the use of the flow switching resulted in a significant increase in the capture efficiency of E. coli, with capture efficiencies up to 83% ± 8% as compared to the constant flow capture efficiencies (up to 39% ± 11%), with a sample size of 3 µL. These results demonstrate the improved performance associated with the use of the electroosmotic flow switching system in a point-of-care bacterial detection assay.


Nutrients ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1613 ◽  
Author(s):  
Ronald Hills ◽  
Benjamin Pontefract ◽  
Hillary Mishcon ◽  
Cody Black ◽  
Steven Sutton ◽  
...  

The gut microbiome plays an important role in human health and influences the development of chronic diseases ranging from metabolic disease to gastrointestinal disorders and colorectal cancer. Of increasing prevalence in Western societies, these conditions carry a high burden of care. Dietary patterns and environmental factors have a profound effect on shaping gut microbiota in real time. Diverse populations of intestinal bacteria mediate their beneficial effects through the fermentation of dietary fiber to produce short-chain fatty acids, endogenous signals with important roles in lipid homeostasis and reducing inflammation. Recent progress shows that an individual’s starting microbial profile is a key determinant in predicting their response to intervention with live probiotics. The gut microbiota is complex and challenging to characterize. Enterotypes have been proposed using metrics such as alpha species diversity, the ratio of Firmicutes to Bacteroidetes phyla, and the relative abundance of beneficial genera (e.g., Bifidobacterium, Akkermansia) versus facultative anaerobes (E. coli), pro-inflammatory Ruminococcus, or nonbacterial microbes. Microbiota composition and relative populations of bacterial species are linked to physiologic health along different axes. We review the role of diet quality, carbohydrate intake, fermentable FODMAPs, and prebiotic fiber in maintaining healthy gut flora. The implications are discussed for various conditions including obesity, diabetes, irritable bowel syndrome, inflammatory bowel disease, depression, and cardiovascular disease.


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