scholarly journals Absolute quantification of E. coli virulence and housekeeping genes to determine pathogen loads in enumerated environmental samples

PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0260082
Author(s):  
K. B. Hoorzook ◽  
T. G. Barnard

Quantifying pathogenic genes with q-PCR in complex samples to determine the pathogen loads is influenced by a wide range of factors, including choice of extraction method, standard curve, and the decision to use relative versus absolute quantification of the genes. The aim was to investigate the standardisation of q-PCR methods to determine enumerated E. coli gene ratios grown with the IDEXX Colilert® Quanti-Trays® using enteropathogenic E. coli as the model pathogen. q-PCR targeting the eaeA and gadAB genes was used to calculate the eaeA: gadAB ratios for clinical strains collected between [2005–2006 (n = 55)] and [2008–2009 (n = 19)] using the LinRegPCR software and Corbett Research Thermal cycler software. Both programs grouped the isolates into two distinct groups based on the gene ratios although the Corbett Research Thermal cycler software gave results one log higher than the LinRegPCR program. Although the eaeA: gadAB ratio range was determined using extracted E. coli DNA, the impact of free DNA and other bacteria present in the sample needed to be understood. Standard curve variations using serially diluted extracted E. coli DNA, serially diluted pure E. coli culture followed by DNA extraction from each dilution with or without other bacteria was tested using the eaeA q-PCR to quantify the genes. Comparison of the standard curves showed no significant difference between standard curves prepared with diluted DNA or with cells diluted before the DNA is extracted (P = 0.435). Significant differences were observed when background DNA was included in the diluent or Coliform cells added to the diluent to dilute cells before the DNA is extracted (P < 0.001). The “carrier” DNA and Coliform cells enhanced the DNA extraction results resulting in better PCR efficiency. This will have an influence on the quantification of gene ratios and pathogen load in samples containing lower numbers of E. coli.

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
S C S Minderhoud ◽  
N Van Der Velde ◽  
J J Wentzel ◽  
M Attrach ◽  
P A Wielopolski ◽  
...  

Abstract Background Phase contrast (PC) CMR flow measurements (FM) are widely used for blood flow assessment, but they suffer from phase offset errors (POE). Stationary phantom correction limits these inaccuracies, however, this adds scan time. Stationary tissue (ST) correction is an alternative method that does not require additional scanning. The aim of this study was to evaluate the impact of POE, to assess interscanner variation, and to evaluate the ST correction usage. Methods We included 166 patients in which both aorta and main pulmonary artery FM were acquired including static gelatin phantom data. Subjects were scanned on three types of 1.5T scanners from the one vendor. Uncorrected and ST corrected FM were compared with phantom corrected FM, our reference value, and corrected for BSA. A difference of >10% in net flow was defined as clinically relevant. Regurgitation fraction was calculated and POE influences were assessed. Regurgitation severity was graded and POE influence on severity grading was assessed. Results Of the 166 cases included, the median age was 27 (5–74) years. Overall, the median difference between no corrected and phantom corrected FM was ≤6%, however, with a wide range of over- and underestimation (−155%–78% change) (figure). ST correction resulted in larger differences compared to no correction (p<0.01). Clinically significant differences were seen in 19% of all FM with no correction and in 30% of with ST correction (p<0.01). Furthermore, there were significant differences between scanners (no correction 10%, p<0.01; ST correction, p<0.01). Regurgitation severity indexing changed in 38 (11%) cases with no correction and in 48 (48%) with ST correction. Magnitude of flow change with and without offset corrections (n=332) Flow (ml/m2) Δ no correction and phantom correction (%) Δ ST correction and phantom correction (%) Clinically significant difference (>10%) Mean ± SD Median IQR Range Median IQR Range No correction, N (%) ST correction , N (%) MRI 1 (n=126) 50±12 3 0 to 6 −8 to 30 5 −3 to 9 −26 to 28 13 (10%) 34 (27%) MRI 2 (n=102) 48±13 −2 −15 to 6 −155 to 78 5 −3 to 11 −74 to 52 50 (49%) 50 (49%) MRI 3 (n=104) 48±12 −1 −1 to 0 −7 to 14 2 −2 to 5 −39 to 29 1 (1%) 16 (15%) Total (n=332) 49±12 0 −2 to 4 −155 to 78 3 −2 to 8 −74 to 52 64 (19%) 100 (30%) Conclusion Background POE have a significant impact on flow quantification and regurgitation severity. Unexpectedly, background correction using ST correction worsens accuracy compared to no correction. POE vary greatly between scanners. Therefore, careful assessment of FM at each scanner is essential to determine if routine phantom scanning is necessary.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 574-574 ◽  
Author(s):  
Christine Jeanblanc ◽  
Evan J Colletti ◽  
Christopher D Porada ◽  
Graca Almeida-Porada ◽  
Esmail Zanjani

Abstract Abstract 574 Many of the most prevalent inherited disorders currently affecting the human population could potentially be treated with IUHSCT. IUHSCT does not require myeloablation, eliminating the risks inherent to this procedure. Moreover, performing IUHSCT during the period of preimmunity removes the recipient's immune response as a barrier to successful engraftment. Unfortunately, despite numerous clinical trials over the last 20 years for a variety of disorders, IUHSCT has only been successful in treating SCID, highlighting the need for a better understanding of the factors governing engraftment following IUHSCT. We hypothesized that the success of IUHSCT likely depends upon: 1) the maturity/receptivity of the bone marrow (BM) niches at the time of transplant; 2) the degree of donor/recipient MHC compatibility; and 3) the source of donor HSC. To test our hypothesis, we began by performing confocal analyses of fetal sheep bones at gestational days 30–145, using sheep as a model based on its immunologic, physiologic and developmental similarities with the human fetus. These analyses showed that the BM microenvironment commences development with the formation of the vascular niche, beginning by day 40 of gestation. In contrast, the osteoblastic niche, which is known to be critical for the engraftment and maintenance of primitive HCS, only starts developing at roughly day 51 of gestation, and does not reach maturity until day 65. These findings thus indicate that to achieve maximal levels of engraftment following IUHSCT, the transplant should likely be performed at gestational day 65 or later, to ensure that the crucial osteoblastic niche has fully developed. Unfortunately, partial immune-competence is also achieved by roughly day 65, suggesting that immune compatibility between the donor and the recipient will also need to be addressed to maximize engraftment. This issue was addressed by transplanting 65 day-old sheep fetuses (n=21) with eGFP-transduced CD34+ cells isolated from related and unrelated BM and cord blood (CB) donors and comparing the levels of engraftment. Cell counting, PCR, and flow cytometry at 63 days post-IUHSCT revealed that the engraftment levels of the related CB HSC were nearly double those of the unrelated CB HSC in BM (1.7% vs. 0.86%) and more than 4-fold higher in PB (2.77% vs. 0.66%). Interestingly, however, there was no significant difference between the engraftment levels of related and unrelated BM-derived HSC (1.77% vs. 1.88%). We presumed that a greater degree of MHC matching could explain the higher engraftment seen with related versus unrelated CB-derived HSC. This was experimentally confirmed by performing PCR-based MHC microsatellite typing at 12 selected MHC loci on the donor CB cells and on amniotic fluid-derived recipient cells. All related donor/recipient animals exhibited 5–7 perfect matches and 1–6 half matches at the 12 MHC loci. In contrast, non-related donor/recipient animals exhibited only 1–2 perfect matches and 4–6 half matches at these loci. To evaluate the impact of the source of HSC on IUHSCT outcome, we compared these same animals without consideration to donor/recipient relatedness. These analyses demonstrated that the CB-derived HSC engrafted in PB at nearly four-fold higher levels than their BM-derived counterparts (2.75% vs. 0.93%). Conversely, the BM-derived HSC engrafted within the recipient BM at three-fold higher levels than the CB-derived HSC (0.66% vs. 2.24%). Collectively, these results suggest that transplanted HSC show a predilection for engraftment in their site of origin. In conclusion, our data collectively indicate that: 1) delaying IUHSCT until a point in gestation when the osteoblastic and vascular niches of the BM are mature is likely to improve engraftment; 2) transplanted HSC exhibit a predilection for engraftment in their site of origin; and 3) higher degrees of CB donor/recipient MHC matching doubles the engraftment levels obtained following IUHSCT, but does not seem to impact upon engraftment levels of BM-derived HSC. By simultaneously addressing these issues, it is expected that curative levels of HSC engraftment can be obtained prior to birth, making it possible to establish clinically successful and reliable IUHSCT-based treatments for a wide range of inherited disorders. Disclosures: No relevant conflicts of interest to declare.


2018 ◽  
Vol 30 (04) ◽  
pp. 1850028 ◽  
Author(s):  
Ateke Goshvarpour ◽  
Atefeh Goshvarpour ◽  
Ataollah Abbasi

Great range of electrocardiogram (ECG) signal processing methods can be found in the literature. In addition, the importance of gender differences in physiological activities was also identified in various conditions. This article aims to provide a comprehensive evaluation of linear and nonlinear ECG parameters to indicate suitable signal processing approaches which can show significant differences between men and women. These differences were investigated in two conditions: (i) during rest condition, and (ii) during the affective image inducements. A wide range of parameters from time-, frequency-, wavelet-, and nonlinear-techniques were examined. Applying the Wilcoxon rank sum test, significant differences between two genders were inspected. The analysis was performed on 47 college students at rest condition and while subjects watching four types of affective pictures, including sadness, happiness, fear, and peacefulness. The impact of these emotions on the results was also investigated. The results indicated that 72.95% and 72.61% of all features were significantly different between male and female in rest condition and affective inducements, respectively. In addition, the highest percentage of the significant difference between ECG parameters of men and women was achieved using nonlinear characteristics. Considering all features together, the highest significant difference between two genders was achieved for negative emotions, including sadness and fear. In conclusion, the results of this study emphasized the importance of gender role in cardiac responses during rest condition and different emotional states. Since these gender differences are well manifested by nonlinear signal processing techniques, dynamical gender-specific ECG system may improve the automatic emotion recognition accuracies.


2021 ◽  
Vol In Press (In Press) ◽  
Author(s):  
Ciamak Ghazaei

: Pseudomonas aeruginosa (P. aeruginosa) has a wide range of virulence factors. These factors have the potential to increase bacterial pathogenicity and serious infection. The purpose of this study was to evaluate the virulence profiles and antibiotic susceptibility of isolates of P. aeruginosa originated from animal and human samples. The samples were cultured on selective media before being extracted for DNA and subjected to a PCR technique to detect virulence genes. There was a significant difference in the isolation of P. areuginosa isolated from human and animal sources. Where, in humans, the percentage of P. areuginosa was 52 (68.42%) while in animals the percentage of P.aeruginosa was 24 (31.57%). In humans, the percentage of P. aeruginosa in blood was 26.92% (14 isolates), in urine it was 25% (13 isolates), in wound it was 40.38%21 isolates), and in sputum it was 7.69% (4 isolates). We used a PCR technique that produced highly specific and accurate results for detecting virulence factor genes in P. aeruginosa isolates that cause disease in humans and animals. The percentage of exoA genes was (83.33%) and (81.66%) in the animal and human, and that of lasB was (58.33%) and (92.30%) in animal and human samples respectively. Furthermore, both the exoA and lasB genes are found in 26.31% of animal strains and 17.10% of human strains. The disc diffusion method was used to determine antimicrobial susceptibility. In both animal and human isolates, P. aeruginosa showed the highest resistance to amikacin and the lowest resistance to ciprofloxacin. These findings could aid in the understanding of pathogenicity processes, treatment direction, and the development of strategies to control the spread of epidemic P. aeruginosa strains.


Author(s):  
Mrudev Gandhi ◽  
Utsav Patel

Background: Dementia is one of the most common and cognitive impairments growing over the globe. It encompasses a wide range of other neurodegenerative disorders with the symptoms such as loss of memory, inability in carrying out everyday activities, a decline in the brain function activities, and perplexity. However, it has been identified that there is an absolute lack of treatment modalities for dementia, but the early diagnosis plays an important role in identifying the cognitive impairment in the asymptomatic phase itself. It helps in preventing the disease from reaching a further complicated stage Aim: To assess the impact of cognitive impairment screening on the management of geriatric hip fractures Methods: It was an observational study carried out at Shree Krishna Hospital, Karamsad; for a period of two years (June 2018 to May 2020). Two hundred sixty patients were included in the study. The patients were divided into three groups, namely hemiarthroplasty (HA), Total Hip Arthroplasty (THA), hemiarthroplasty in patients with known dementia (HAd). Result: The study showed male preponderance in the study, and the majority of the patients were above 80 years of age. There was a significant difference in the patients who can perform their grocery or medication independently and not independently with respect to MMSE. However, there was no statistically significant difference in Hip Harris Score. There was a statistically significant difference among the three groups regarding the intraoperative blood, operation duration, hospital stay, ICU postoperative, in-hospital details. Conclusion: In light of the above literature, it was found that hip fractures and cognitive impairment were closely related. There are many risk factors of hip fracture, which are aggravated due to the late diagnosis of cognitive impairment. The incidence of hip fracture among patients suffering from dementia was much higher as compared to normal patients. Keywords: multi-morbidity, cognitive impairment, geriatric hip fracture


BJPsych Open ◽  
2021 ◽  
Vol 7 (S1) ◽  
pp. S242-S243
Author(s):  
Hongying Chen ◽  
Michael Devine ◽  
Waqar Khan ◽  
Iqbal Z Khan ◽  
Ronan P Waldron ◽  
...  

AimsPsychiatric disorders are increasingly prevalent and present as a comorbidity in many hospitalized patients. Studies have demonstrated that the presence of comorbid psychiatric conditions (CPC) is associated with worsened inpatient outcomes. Emergency surgical admissions and the impact of CPC on their outcomes has not been studied in Ireland to date. This study aims to provide a comprehensive analyses of the relationship between a wide range of psychiatric comorbidities and surgical presentations.MethodThe Hospital In-Patient Enquiry (HIPE) and prospectively maintained electronic patient records were used to identify all surgical emergency admissions between 31st August 2019 and 1st September 2020 to Mayo University Hospital, Ireland. Patient demographics, comorbidities, primary diagnoses, length of stay (LoS), discharge destination, and surgical interventions were recorded. Subgroup analyses were performed examining LoS variation in the type of surgical presentation. Physical comorbidities were scored using the Charlson Comorbidity Index (CCI). Statistical calculations were performed using SPSS.ResultA total of 995 admissions were recorded. The presence of CPC increased the overall mean LoS by 1.9 days (p = .002). This trend was observed in both operative and conservative management. Significant increase in LoS was noted in patients with a comorbid depression (2.4 days, p = .003), dementia (2.8 days, p = .019), and intellectual disability (6.7 days, p = .007). Subgroup analysis revealed greater LoS in patients with CPC diagnosed with non-specific abdominal pain (1.4 days, p = .019), skin and soft tissue infections (2.5 days, p = .040), bowel obstruction (4.3 days, p = .047), and medical disorders (18.6 days, p = .010). The odds of nursing home or convalescence as a discharge destination was 2.44 (95% CI: 1.37–4.35, p = 0.002) in patients with CPC and the odds of self-discharge against medical advice in this population was 4.89 (95% CI: 1.43–16.70, p = 0.005). No significant difference was observed in mortality and readmission rates.ConclusionPsychiatric comorbidities significantly impact length of hospital stay and influence discharge planning in surgical inpatients. Greater vigilance is required in providing care for patients with psychiatric comorbidities, particularly those with depression, dementia and intellectual disability. Better optimisation of facilities and a more personalised approach to patients with CPC are required to improve inpatient outcomes and resource allocation.


2020 ◽  
Vol 82 (6) ◽  
pp. 13-22
Author(s):  
L.A. Dankevych ◽  
◽  
N.O. Leonova ◽  
G.O. Iutynska ◽  
A.V. Kalinichenko ◽  
...  

It is known that plant protection against diseases is based mainly on the use of pesticides. These chemicals or their degradation products have a detrimental effect on the environment and human health. Due to this, the search for methods of plant protection that are safe for the environment is becoming increasingly popular. Induction of plant resistance to disease is one of the promising non-chemical ways of protection, in which plant enzymes play a key role. It was shown that in response to pathogen invasion, plants enhance protective properties by inducing the activity of a wide range of enzymes that slow the spread of infection, in particular: peroxidases, β-1,3-glucanases, chitinases, polyphenol oxidases and L-phenylalanine ammonia-lyase (PAL). The aim of the research was to study the change in PAL activity in soybean and lupine plants under conditions of artificial infection with some phytopathogenic bacteria of the Pseudomonas genus and under the action of Ecovital and EPAA-M biological preparations. Methods. PAL activity was determined spectrophotometrically. Changes of soybean (Glycine max) and lupine (Lupinus luteus L.) plants resistance to diseases caused by bacteria of the Pseudomonas genus were evaluated using phytopathological methods. Statistical processing of the research results was performed using MS Excel computer program with Student’s t-test and estimation of least significant difference (LSD). Results. It was found that under conditions of soybean and lupine plants infection with phytopathogenic bacteria of the Pseudomonas genus on the background of pre-sowing seed treatment with Ekovital and EPAA-M biological preparations, composition based on them and synthetic standard – salicylic acid a significant increase in FAL activity in the aboveground and the degree of infectious roots – reducing of plants with pathogens was observed. It has been established that the growth of PAL activity under the condition of infection with phytopathogenic bacteria of the Pseudomonas genus occurs after 2–6 h and lasts up to 7 days from the moment of phytopathogen invasion into the plant. The most increasing of PAL activity was after treatment of seeds with Ecovital and EPAA-M composition – by 38.1–73.3% (Lupinus luteus L.) and 60.4–110% (Glycine max) compared to the control. Treatment with the composition of biological products also helped to reduce the degree of plant damage. PAL activity increasing and reducing the area of soybean and lupine leaves affected surface can indicate the induction of protective reactions in plants. Conclusions. The use of the composition of EPAA-M with the microbial preparation Ecovital contribute to the increase of PAL activity and the formation of resistance to phytopathogenic bacteria of the genus Pseudomonas in Glycine max and Lupinus luteus L. plants.


2019 ◽  
Vol 150 (3) ◽  
pp. 512-517
Author(s):  
Maryanne T Perrin ◽  
Roman Pawlak ◽  
Lindsay H Allen ◽  
Daniela Hampel

ABSTRACT Background Choline is an essential nutrient for brain growth and other processes in the developing neonate. The impact of a maternal plant-based diet on the choline composition of breast milk is unknown. Objective We assessed the water-soluble choline content of milk from lactating women in the United States following 3 dietary patterns: vegan, vegetarian, and nonvegetarian. Methods We conducted a cross-sectional study of 74 healthy lactating women who provided a single breast-milk sample using a standardized collection protocol. Participants completed a food-frequency screener and were classified as follows: nonvegetarians (NONVEG) consumed meat; vegetarians (VEGT) consumed milk, dairy, and/or fish; and vegans (VEGAN) consumed animal products less than monthly. Primary outcomes measured were the concentration (in milligrams per liter) and distribution (percentage) of choline from the following water-soluble forms: free choline, phosphocholine (PCho), and glycerophosphocholine (GPC). Differences between diet groups were evaluated with ANOVA. Results There was a wide range in breast-milk total water-soluble choline (4–301 mg/L), with no significant difference (P &gt; 0.05) by maternal diet pattern. There were differences in choline forms, with VEGAN having a greater mean ± SD concentration and distribution of choline derived from GPC (62.7 ± 25.3 mg/L) than VEGT (47.7 ± 21.2 mg/L) and NONVEG (42.4 ± 14.9 mg/L) (P = 0.0052). There was a lower mean ± SD percentage of choline from PCho (P = 0.0106) in VEGAN (32.5% ± 18.3%) than in VEGT (46.1% ± 18.3%) and NONVEG (44.8% ± 15.7%). Lactation stage and maternal BMI were significantly associated with some choline forms. Conclusions There was a wide range of water-soluble choline concentrations in the milk of healthy lactating women following vegan, vegetarian, and nonvegetarian diets, with no observed difference in total water-soluble choline concentration by maternal diet. This suggests that maternal plant-based diet by itself is not a risk factor for low breast-milk choline.


2020 ◽  
Author(s):  
Yibelu Yitayih ◽  
Dessalegn Ejigu ◽  
Misganaw Mola

Abstract Background: Grivet monkey (Chlorocebus aethiops) is an Old World monkey with long white tufts of hair along the sides of the face. They inhabit a wide range of habitat types. A study on population size and human-grivet monkey conflict in Zegie Peninsula was carried out from August 2019 to March 2020; the study comprised both the wet and dry seasons. The line transect method was used to collect data on the population size of grivet monkeys. Questionnaire and focus group discussions were used to study the human-grivet monkey conflict and its conservation status. Results: The estimated population of grivets in the study area was 4808. Population structure of grivets indicated that there were 634 adult males, 1236 adult females, 1733 juveniles, and 1205 infants. Grivet population estimate between the wet and dry seasons did not show significant differences (ᵡ2 = 0.938, df = 1, p > 0.05). But there was a significant difference in the population estimate of grivets among the different habitats (ᵡ2 = 238.295, df = 3, p < 0.05).Conclusion: There was a human-grivet monkey conflict in the Peninsula and grivets were damaged crops, not only crops but also predating poultry, steal an egg, and human food. Consequently, grivets were killed in response to the damage they cause to crops. Grivet’s habitat in the Peninsula is highly disturbed because the local people cut trees for sale to support their livelihood. Awareness creation of the residents about wildlife and their habitat is necessary, and people should understand the impact of deforestation, illegal hunting, and the role of grivets in the ecosystem at large. Hence there is a need to protect the forest in order to ensure sustainable conservation of biodiversity in general and grivet monkeys in particular.


2019 ◽  
Vol 31 (1) ◽  
pp. 197 ◽  
Author(s):  
M. Stoltzfus ◽  
J. Wayman ◽  
R. Stilz ◽  
D. Bresnahan

Goats are important livestock species because they produce meat, milk, and fibre and are also easily maintainable on small farms. Although goats provide many products and consumption of goat meat is increasing in the United States, the industry lags compared with many species with regard to IVF techniques to enhance goat production. It has been demonstrated in other species that male IVF embryos tend to develop faster than those of females. This may be due to increased tolerance of male embryos to inadequate conditions, particularly, glucose concentrations in culture media. However, the sex ratio of goat embryos produced utilising IVF remains unknown. The aim of this study was to determine the sex ratio of goat embryos utilising a commercially available media suite (IVF Biosciences, Falmouth, UK). Oocytes were harvested from ovaries obtained from 2 local abattoirs and matured in vitro. Frozen sperm from 1 of 2 billy goats were randomly assigned for each round of IVF. Embryos were evaluated daily from Days (D) 6 through 9 of in vitro culture. On the day an embryo reached the expanded blastocyst stage, it was removed from culture and placed into DNA extraction buffer (PicoPureTM DNA Extraction Kit, Applied Biosystems, Waltham, MA, USA) and stored at −20 for PCR analysis, typically within one month of collection. In all unknown samples, positive male (sperm) and female (uterus) controls, the amelogenin gene was amplified and products were evaluated on a 1.5% agarose gel with ethidium bromide. Embryos with 2 bands (202 and 262bp) were classified as male, and those with 1 band (262bp) were classified as female. Embryos with no bands were not included in analysis. Embryos reached the expanded blastocyst stage on D6 (n=29), D7 (n=39), and D8/9 (n=35, combined for evaluation). A chi-squared analysis comparing the percentage of male and female embryos to the expected 50% was completed for each time point (D6, D7, D8/9), as well as overall ratios (D6-9). In total, 350 oocytes were utilised in 6 rounds of IVF resulting in a mean blastocyst rate of 32% (range 17-47%). There was no significant difference in the number of embryos that were male on D6 (55%) and D7 (46%). However, on D8/9 significantly fewer embryos were male (29% male; P=0.01). Overall, there was no significant difference (P=0.14) in the sex ratio, with 41% male and 59% female embryos. Our findings are somewhat consistent with other species, in that male goat embryos produced via IVF develop more quickly in culture conditions; however, female embryos were still able to tolerate culture conditions. Delayed blastocyst development may not necessarily be an indication of a reduced quality embryo but one that is slower to develop based on its sex. This could be due to expression of X-linked genes being unbalanced during pre-implantation embryo development stages and warrants further study. One influencer of sex ratio we are currently investigating is the impact of glucose during culture, to further understand metabolism in IVF embryos.


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