scholarly journals Filamentous phages reduce bacterial growth in low salinities

2019 ◽  
Vol 6 (12) ◽  
pp. 191669 ◽  
Author(s):  
Henry Goehlich ◽  
Olivia Roth ◽  
Carolin C. Wendling
Keyword(s):  
Bacterial Growth ◽  
Network Structure ◽  
Bacterial Communities ◽  
Marine Bacterium ◽  
Indirect Measure ◽  
High Frequencies ◽  
Fitness Effects ◽  
Significant Difference ◽  
Bacterial Fitness ◽  
Filamentous Phages

Being non-lytic, filamentous phages can replicate at high frequencies and often carry virulence factors, which are important in the evolution and emergence of novel pathogens. However, their net effect on bacterial fitness remains unknown. To understand the ecology and evolution between filamentous phages and their hosts, it is important to assess (i) fitness effects of filamentous phages on their hosts and (ii) how these effects depend on the environment. To determine how the net effect on bacterial fitness by filamentous phages changes across environments, we constructed phage–bacteria infection networks at ambient 15 practical salinity units (PSU) and stressful salinities (11 and 7 PSU) using the marine bacterium, Vibrio alginolyticus and its derived filamentous phages as model system. We observed no significant difference in network structure at 15 and 11 PSU. However, at 7 PSU phages significantly reduced bacterial growth changing network structure. This pattern was mainly driven by a significant increase in bacterial susceptibility. Our findings suggest that filamentous phages decrease bacterial growth, an indirect measure of fitness in stressful environmental conditions, which might impact bacterial communities, alter horizontal gene transfer events and possibly favour the emergence of novel pathogens in environmental Vibrios .

scholarly journals The distribution of plasmid fitness effects explains plasmid persistence in bacterial communities

2020 ◽  
Author(s):  
Aida Alonso-del Valle ◽  
Ricardo León-Sampedro ◽  
Jerónimo Rodríguez-Beltrán ◽  
Javier DelaFuente ◽  
Marta Hernández-García ◽  
...  
Keyword(s):  
Bacterial Communities ◽  
Plasmid Stability ◽  
Wild Type ◽  
Bacterial Populations ◽  
Beneficial Effects ◽  
Fitness Effects ◽  
Population Dynamics Model ◽  
Bacterial Fitness ◽  
Plasmid Carriage ◽  
General Explanation

Introductory paragraphPlasmid persistence in bacterial populations is strongly influenced by the fitness effects associated with plasmid carriage. However, plasmid fitness effects in wild-type bacterial hosts remain largely unexplored. In this study, we determined the distribution of fitness effects (DFE) for the major antibiotic resistance plasmid pOXA-48 in wild-type, ecologically compatible enterobacterial isolates from the human gut microbiota. Our results show that although pOXA-48 produced an overall reduction in bacterial fitness, the DFE was dominated by quasi-neutral effects, and beneficial effects were observed in several isolates. Incorporating these data into a simple population dynamics model revealed a new set of conditions for plasmid stability in bacterial communities, with plasmid persistence increasing with bacterial diversity and becoming less dependent on conjugation. Moreover, genomic results showed a link between plasmid fitness effects and bacterial phylogeny, helping to explain pOXA-48 epidemiology. Our results provide a simple and general explanation for plasmid persistence in natural bacterial communities.

scholarly journals Variability of plasmid fitness effects contributes to plasmid persistence in bacterial communities

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Aida Alonso-del Valle ◽  
Ricardo León-Sampedro ◽  
Jerónimo Rodríguez-Beltrán ◽  
Javier DelaFuente ◽  
Marta Hernández-García ◽  
...  
Keyword(s):  
Bacterial Communities ◽  
Plasmid Stability ◽  
Wild Type ◽  
Bacterial Populations ◽  
Beneficial Effects ◽  
Fitness Effects ◽  
Population Dynamics Model ◽  
High Prevalence ◽  
Bacterial Fitness ◽  
Plasmid Carriage

AbstractPlasmid persistence in bacterial populations is strongly influenced by the fitness effects associated with plasmid carriage. However, plasmid fitness effects in wild-type bacterial hosts remain largely unexplored. In this study, we determined the fitness effects of the major antibiotic resistance plasmid pOXA-48_K8 in wild-type, ecologically compatible enterobacterial isolates from the human gut microbiota. Our results show that although pOXA-48_K8 produced an overall reduction in bacterial fitness, it produced small effects in most bacterial hosts, and even beneficial effects in several isolates. Moreover, genomic results showed a link between pOXA-48_K8 fitness effects and bacterial phylogeny, helping to explain plasmid epidemiology. Incorporating our fitness results into a simple population dynamics model revealed a new set of conditions for plasmid stability in bacterial communities, with plasmid persistence increasing with bacterial diversity and becoming less dependent on conjugation. These results help to explain the high prevalence of plasmids in the greatly diverse natural microbial communities.

scholarly journals Detection of Myocardial Infarction Using ECG and Multi-Scale Feature Concatenate

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1906
Author(s):  
Jia-Zheng Jian ◽  
Tzong-Rong Ger ◽  
Han-Hua Lai ◽  
Chi-Ming Ku ◽  
Chiung-An Chen ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Network Structure ◽  
Class Imbalance ◽  
Class Imbalance Problem ◽  
Multi Scale ◽  
Imbalance Problem ◽  
Average Accuracy ◽  
Significant Difference ◽  
Electrocardiogram Ecg

Diverse computer-aided diagnosis systems based on convolutional neural networks were applied to automate the detection of myocardial infarction (MI) found in electrocardiogram (ECG) for early diagnosis and prevention. However, issues, particularly overfitting and underfitting, were not being taken into account. In other words, it is unclear whether the network structure is too simple or complex. Toward this end, the proposed models were developed by starting with the simplest structure: a multi-lead features-concatenate narrow network (N-Net) in which only two convolutional layers were included in each lead branch. Additionally, multi-scale features-concatenate networks (MSN-Net) were also implemented where larger features were being extracted through pooling the signals. The best structure was obtained via tuning both the number of filters in the convolutional layers and the number of inputting signal scales. As a result, the N-Net reached a 95.76% accuracy in the MI detection task, whereas the MSN-Net reached an accuracy of 61.82% in the MI locating task. Both networks give a higher average accuracy and a significant difference of p < 0.001 evaluated by the U test compared with the state-of-the-art. The models are also smaller in size thus are suitable to fit in wearable devices for offline monitoring. In conclusion, testing throughout the simple and complex network structure is indispensable. However, the way of dealing with the class imbalance problem and the quality of the extracted features are yet to be discussed.

scholarly journals Characterisation of Bt maize IE09S034 in decomposition and response of soil bacterial communities

2021 ◽  
Author(s):  
Xiaoli Zhou ◽  
Jingang Liang ◽  
Ying Luan ◽  
Xinyuan Song ◽  
Zhengguang Zhang
Keyword(s):  
Metabolic Activity ◽  
Bacterial Communities ◽  
Bt Maize ◽  
Gm Crop ◽  
Soil Bacterial Communities ◽  
Significant Difference ◽  
Maize Residues ◽  
Soil Bacterial ◽  
June July ◽  
The Impact

Returning straw to the soil is an effective way to improve the soil quality. As genetically modified (GM) crops experience expanded growing scales, returning straw to the soil could also be necessary. However, the impact of GM crop straws on soil safety remains unclear. The environment (including soil types, humidity and temperature) can result in a significant difference in the diversity of soil bacterial communities. Here, we compared the impacts of the straw from Bt maize IE09S034 (IE) and near-isogenic non-Bt maize Zong31 (CK) on soil bacterial community and microbial metabolic activity in three different environments. Sampling was carried out following 6–10 months of decomposition (May, June, July, and August) in three localities in Chinese cities (Changchun, Jinan, and Beijing). Our results showed that Bt maize residues posed no direct impact on soil bacterial communities in contrast to the environment and decomposed time. The microbial functional diversity and metabolic activity showed no significant difference between IE and CK. The results could be a reference for further assessing the effect of Bt maize residues on the soil that promotes the commercialisation of Bt maize IE09S034.

Evaluation of Hepatitis C Patients' Satisfaction Regarding Care and Treatment in Different Hospitals in Cairo, Egypt, 2020

QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Shaimaa S Yousef ◽  
Lamyaa S Al Bagoury ◽  
Sahar A Dewedar ◽  
Sahar M Sabbour ◽  
Wagida A Anwar
Keyword(s):  
Viral Hepatitis ◽  
Demographic Data ◽  
University Hospital ◽  
Health Providers ◽  
Cross Sectional ◽  
Indirect Measure ◽  
Patients Satisfaction ◽  
Significant Difference ◽  
Care And Treatment

Abstract Background Patient satisfaction can be considered as an indirect measure of health outcomes and quality of provided services. Objectives To compare HCV patients' satisfaction regarding care and treatment in different selected Viral Hepatitis Outpatients Clinics in Cairo. Method: The current study is a cross sectional study. It recruited 300 HCV patients from Viral Hepatitis Outpatients Clinics in University, Ministry of Health (MOH) and Insurance Hospitals (100 HCV patients from each clinic). Recruited HCV patients attended at least 2 visits to the Viral Hepatitis Clinics. They completed an interview questionnaire about socio- demographic data, history of diagnosis of HCV, onset and type of treatment and Hepatitis Patients Satisfaction Questionnaire (HPSQ). Results Mean age of HCV patients were (48.9 ±13.5), (50.4 ± 10.4), and (54.8 ± 10.9) from University, MOH and Insurance Hospitals, respectively. Females accounted for (63%) of HCV patients in University Hospital sample however, males were (54%) and (57%) in MOH and Insurance Hospitals, respectively. Most of studied HCV patients were referred by specialists; (59%), (86%) and (87%) from University, MOH, and Insurance Hospitals, respectively. A statistically significant difference was found between the 3 Clinics as regards rating the quality of received HCV services, meeting patients’ needs, coping with HCV disease, and helping patients access to specialist services (p &lt; 0.01). The study revealed that the majority of health providers in the 3 Viral Hepatitis Clinics didn't involve HCV patients in making decisions about their treatment. Conclusion HPSQ findings identified University Hospital's patients more satisfied about their HCV treatment management than MOH and Insurance Hospitals' patients except for involvement of HCV patients in making decisions which was lacking in the 3 hospitals.

scholarly journals Profiling the Bacterial Diversity in a Typical Karst Tiankeng of China

Biomolecules ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 187 ◽  
Author(s):  
Gaozhong Pu ◽  
Yanna Lv ◽  
Lina Dong ◽  
Longwu Zhou ◽  
Kechao Huang ◽  
...  
Keyword(s):  
Bacterial Community ◽  
Bacterial Communities ◽  
Soil Microorganisms ◽  
Operational Taxonomic Unit ◽  
Soil Characteristics ◽  
Soil Samples ◽  
Controlling Factors ◽  
Bacterial Composition ◽  
Microbial Distribution ◽  
Significant Difference

While karst tiankengs have a higher capacity to act as safe havens for biodiversity in changing climates, little is known about their soil microorganisms. To fill this gap, we investigate the distribution and driving factors of the bacterial community in karst tiankeng systems. There is a significant difference in the soil characteristics between the inside and the outside of a karst tiankeng. At the karst tiankeng considered in this study, the bacterial composition, in terms of the operational taxonomic unit (OTU), was found to be significantly different in different soil samples, taken from diverse sampling sites within the collapsed doline or the external area, and showed a high habitat heterogeneity. The dominant phylum abundances vary with the sampling sites and have their own indicator taxa from phylum to genus. Unlike the primary controlling factors of plant diversity, the microclimate (soil moisture and temperature), soil pH, and slope dominated the distribution of the bacterial community in karst tiankeng systems. Our results firstly showed the distribution characteristics of bacterial communities and then revealed the importance of microhabitats in predicting the microbial distribution in karst tiankeng systems.

scholarly journals Characterization of bacterial communities of rhizosphere and rhizoplane of Early Zhukovsky potato

2020 ◽  
Vol 222 ◽  
pp. 02050
Author(s):  
Marat Lutfulin ◽  
Darya Zaripova ◽  
Oksana Moiseeva ◽  
Semen Vologin ◽  
Ayslu Mardanova
Keyword(s):  
Bacterial Communities ◽  
Functional Role ◽  
Agricultural Crop ◽  
Potato Root ◽  
Bacterial Microbiota ◽  
16S R Rna ◽  
Significant Difference ◽  
Dominant Bacteria

Identification of patterns of formation of bacterial communities of the rhizosphere and rhizoplane of potato (Solanum tuberosum L.), the most important agricultural crop, is necessary for the introduction and maintenance of sustainable organic farming. The purpose of this work was the study of the biodiversity of the bacterial microbiota of the rhizosphere and rhizoplane of Early Zhukovsky potato, cultivated on gray forest soils. Comparative analysis based on sequencing of the 16S R RNA gene showed a significant difference in the representation of different groups of bacteria in these potato root compartments. Thus, the proportions of the dominant bacteria in the rhizosphere and rhizoplane of the Proteobacteria phylum reach 47.66% ± 7.22 % and 86.35 % ± 0.53%, respectively (P < 0.05). In contrast, the representation of phylum Bacteroidetes and Firmicutes in the rhizosphere is significantly higher and reaches 41.45 % ± 10.42% and 6.49 % ± 3.23%, respectively, compared to the rhizoplane (7.84 % ± 1.24 % and 0.43 % ± 0.48 %, (P < 0.05). At the same time, Actinobacteria phylum bacteria are present in both compartments in approximately equal amounts (4.40 % ± 1.81% in the rhizosphere and 5.37 % ± 1.42% in the rhizoplane). Thus, it was found that potato forms different bacterial communities in the rhizosphere and rhizoplane in quantitative proportions, which is probably determined by the functional role of these microorganisms in the plant physiology.

scholarly journals Bacterial growth response to copepod grazing in aquatic ecosystems

2007 ◽  
Vol 87 (3) ◽  
pp. 667-674 ◽  
Author(s):  
Cristian A. Vargas ◽  
L. Antonio Cuevas ◽  
Humberto E. González ◽  
Giovanni Daneri
Keyword(s):  
Food Web ◽  
Bacterial Growth ◽  
Bacterial Communities ◽  
Aquatic Ecosystems ◽  
Field Measurements ◽  
Zooplankton Biomass ◽  
Aquatic Environments ◽  
Coastal Embayment ◽  
Copepod Grazing ◽  
Bacterial Assemblages

The growth rate response of bacterial communities to the potential increase of dissolved organic matter (DOM) produced by the copepod Acartia tonsa was assessed in experiments conducted in three stations representing three contrasting aquatic environments (coastal embayment, shelf and ocean). Bacterial assemblages were inoculated in filtered seawater where A. tonsa had previously grazed. Utilization of DOM over time was evaluated after the addition of bacterial inoculums as the biomass changes in both ‘control’ and ‘copepod’ treatments. In the embayment and ocean a high bacterial growth was observed in the treatments with seawater where copepod were feeding. Additional field measurements of bacterial, primary production and zooplankton biomass support the idea that bacterial communities living in oceanic environments can be efficient to utilize the newly available substrate. Copepods play a key role not only as conveyors of carbon up through the classical food-web, but also generated significant amounts of bacterial substrate in the microbial loop food-web.

Distance from the anal verge as an indirect measure to predict response to anti-EGFR therapy in left side metastatic colon cancer.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. e15153-e15153
Author(s):  
Daniela Pezzutti DOMINGUES Armentano ◽  
Mariana Ribeiro Monteiro ◽  
Raphael Araujo ◽  
Renata Arakelian ◽  
Paula Freire Cardoso ◽  
...  
Keyword(s):  
Anal Verge ◽  
Tumor Location ◽  
Response To Therapy ◽  
Rank Test ◽  
Metastatic Colon Cancer ◽  
Indirect Measure ◽  
Colon Cancers ◽  
Significant Difference ◽  
Group A ◽  
Group B

e15153 Background: Right and left sided colon cancers (RC, LC) differ with respect to biology and response to therapy. Several retrospective analyses have assessed the clinical effect of epidermal growth fator receptor (EGFR) targeted agents in patients with metastatic CRC (mCRC) according to the primary tumor location. Differentiating only right from left. But can in the LC responses differ according to the distance from the anal verge (DAV)? Methods: Exploratory retrospective analyses was planned to evaluate if LC responses differ according to the DAV. LC was defined as tumors originating anywhere from the distal rectum to the left colic flexure (splenic flexure). DAV was describe in cm measured by previous to surgery or treatment, colonoscopy, CT or MRI. Patients were divided for analysis purposes in two groups: Group A (tumors above 12cm from de anal verge), Group B (tumors below 12cm from the anal verge). Results: We retrospectively evaluated 29 patients with left metastatic colorectal cancer treated with anti-EGFR therapy as part of their treatment at the Paulistano Hospital -São Paulo from 2011 to 2018. Median population age 51.8 years (48.5-62.3). Median DAV 14.5 (4.6-25 cm). Median follow-up 12.8 months. No significant difference on stable and partial response rate was detected (Group A 43.7% vs Gropup B 56.3%), p=0.211. Long-rank test with a median pFS 8,5 meses and a PFS at 6 months of 66.7 vs 78,8 (Group A and Group B respectively ), p=0.901. Two-year OS was 58.4 % in Group A and 100% in Group B, p=0.17. Conclusions: Although no significant diferences were detected, responses rates were numerically higher in patients with tumors located below 12 cm from the anal verge. Further studies are needed to evaluate the association between response and DAV.

scholarly journals Extended High Frequency Audiometry in Polycystic Ovary Syndrome

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Cuneyt Kucur ◽  
Suna Kabil Kucur ◽  
Ilay Gozukara ◽  
Ali Seven ◽  
Kadriye Beril Yuksel ◽  
...  
Keyword(s):  
Hearing Impairment ◽  
High Frequency ◽  
Polycystic Ovary ◽  
Endothelial Damage ◽  
Reproductive Age ◽  
Control Group ◽  
Fasting Insulin ◽  
High Frequencies ◽  
High Frequency Audiometry ◽  
Significant Difference

Objective. Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder affecting 5–10% of women in reproductive age. Insulin resistance, dyslipidemia, glucose intolerance, hypertension, and obesity are metabolic disorders accompanying the syndrome. PCOS is a chronic proinflammatory state and the disease is associated with endothelial dysfunction. In diseases with endothelial damage, hearing in high frequencies are mostly effected in early stages. We evaluated extended high frequency hearing loss in PCOS patients.Material Methods. Forty women diagnosed as PCOS and 25 healthy controls were included in this study. Age and BMI of PCOS and control groups were comparable. Each subject was tested with low (250–2000 Hz), high (4000–8000 Hz), and extended high frequency audiometry (8000–20000). Hormonal and biochemical values including LH, LH/FSH, testosterone, fasting glucose, fasting insulin, HOMA-I, and CRP were calculated.Results. PCOS patients showed high levels of LH, LH/FSH, testosterone, fasting insulin, glucose, HOMA-I, and CRP levels. The hearing thresholds of the groups were similar at frequencies of 250, 500, 1000, 2000, and 4000 Hz; statistically significant difference was observed in 8000–14000 Hz in PCOS group compared to control group.Conclusion. PCOS patients have hearing impairment especially in extended high frequencies. Further studies are needed to help elucidate the mechanism behind hearing impairment in association with PCOS.

Sign in / Sign up

Export Citation Format

Share Document