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A promising yet clinically unexploited antibiotic target in difficult-to-treat Gram-negative bacteria is LpxC, the key enzyme in the biosynthesis of lipopolysaccharides, which are the major constituents of the outer membrane. Despite the development of dozens of chemically diverse LpxC inhibitor molecules, it is essentially unknown how bacteria counteract LpxC inhibition. Our study provides comprehensive insights into the response against five different LpxC inhibitors. All compounds bound to purified LpxC from Escherichia coli. Treatment of E. coli with these compounds changed the cell shape and stabilized LpxC suggesting that FtsH-mediated proteolysis of the inactivated enzyme is impaired. LpxC inhibition sensitized E. coli to vancomycin and rifampin, which poorly cross the outer membrane of intact cells. Four of the five compounds led to an accumulation of lyso-phosphatidylethanolamine, a cleavage product of phosphatidylethanolamine, generated by the phospholipase PldA. The combined results suggested an imbalance in lipopolysaccharides and phospholipid biosynthesis, which was corroborated by the global proteome response to treatment with the LpxC inhibitors. Apart from LpxC itself, FabA and FabB responsible for the biosynthesis of unsaturated fatty acids were consistently induced. Upregulated compound-specific proteins are involved in various functional categories, such as stress reactions, nucleotide, or amino acid metabolism and quorum sensing. Our work shows that antibiotics targeting the same enzyme do not necessarily elicit identical cellular responses. Moreover, we find that the response of E. coli to LpxC inhibition is distinct from the previously reported response in Pseudomonas aeruginosa.
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Amidohidrolasas , Inhibidores Enzimáticos , Escherichia coli , Amidohidrolasas/antagonistas & inhibidores , Amidohidrolasas/metabolismo , Antibacterianos/farmacología , Antibacterianos/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Escherichia coli/efectos de los fármacos , Escherichia coli/enzimología , Lipopolisacáridos/biosíntesis , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/enzimología , Farmacorresistencia Bacteriana/efectos de los fármacos , Membrana Celular/efectos de los fármacosRESUMEN
The outer membrane (OM) of Gram-negative bacteria functions as an essential barrier and is characterized by an asymmetric bilayer with lipopolysaccharide (LPS) in the outer leaflet. The enzyme LpxC catalyzes the first committed step in LPS biosynthesis. It plays a critical role in maintaining the balance between LPS and phospholipids (PL), which are both derived from the same biosynthetic precursor. The essential inner membrane proteins YejM (PbgA, LapC), LapB (YciM), and the protease FtsH are known to account for optimal LpxC levels, but the mechanistic details are poorly understood. LapB is thought to be a bi-functional protein serving as an adaptor for FtsH-mediated turnover of LpxC and acting as a scaffold in the coordination of LPS biosynthesis. Here, we provide experimental evidence for the physical interaction of LapB with proteins at the biosynthetic node from where the LPS and PL biosynthesis pathways diverge. By a total of four in vivo and in vitro assays, we demonstrate protein-protein interactions between LapB and the LPS biosynthesis enzymes LpxA, LpxC, and LpxD, between LapB and YejM, the anti-adaptor protein regulating LapB activity, and between LapB and FabZ, the first PL biosynthesis enzyme. Moreover, we uncovered a new adaptor function of LapB in destabilizing not only LpxC but also LpxD. Overall, our study shows that LapB is a multi-functional protein that serves as a protein-protein interaction hub for key enzymes in LPS and PL biogenesis presumably by virtue of multiple tetratricopeptide repeat (TPR) motifs in its cytoplasmic C-terminal region.
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Proteínas de Escherichia coli , Lipopolisacáridos , Lipopolisacáridos/metabolismo , Escherichia coli/metabolismo , Proteínas de la Membrana/metabolismo , Fosfolípidos/metabolismo , Amidohidrolasas/metabolismo , Proteínas de Escherichia coli/metabolismoRESUMEN
BACKGROUND: Somatisation is a highly prevalent psychiatric syndrome in both women and men, in which psychological distress is manifested in physical symptoms without a medical explanation. Many patients with somatisation disorder are high healthcare utilisers, particularly at emergency departments. Unnecessary investigations and diagnostic operations occur frequently, which cause both patient suffering and a significant burden on the healthcare system. Emergency department physicians' awareness of somatisation and its manifestations has not previously been studied. This study aimed to investigate awareness about somatisation disorder among physicians working at emergency departments in western Sweden, and to explore differences between gender, specialty, and work experience. METHODS: A web-based, cross-sectional survey consisting of six dichotomous questions about somatisation disorder was conducted, in December 2021 - January 2022, among licensed physicians of various specialties working at emergency departments in western Sweden. Descriptive analyses and comparative analyses were performed to investigate differences between gender, type of specialty, and years of practice. Data were analysed using chi2 tests and Fisher's exact test. RESULTS: Of the 526 eligible physicians who received the survey, 241 responded; response rate 45.8%. The majority of the respondents (56.4%) were women, and most (35.3%) were specialised in obstetrics/gynaecology. Average years of work experience was 11.1 (SD 8.7) years. Although 71% of respondents were aware of the diagnosis, only 7% knew the diagnostic criteria and only 6% had ever diagnosed a patient with somatisation disorder. Female physicians were more aware of underlying factors than their male colleagues (55.7% vs. 38.2%; p = .010). Type of specialty or years of practice did not affect awareness. CONCLUSIONS: Awareness of somatisation disorder is low among physicians working at emergency departments in western Sweden. The findings suggest a need to increase awareness and knowledge and provide training in diagnosing the condition, to ensure correct decisions and optimal patient management. Clinical guidelines need to be developed to support diagnosis, investigation, and treatment, in Sweden as well as internationally.
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Medicina , Médicos , Humanos , Masculino , Femenino , Estudios Transversales , Suecia , Servicio de Urgencia en Hospital , Encuestas y Cuestionarios , Médicos/psicologíaRESUMEN
INTRODUCTION: Team-based learning (TBL) is a well-established active teaching method which has been shown to have pedagogical advantages in some areas such as business education and preclinical disciplines in undergraduate medical education. Increasingly, it has been adapted to clinical disciplines. However, its superiority over conventional learning methods used in clinical years of medical school remains unclear. The aim of this study was to compare TBL with traditional seminars delivered in small group interactive learning (SIL) format in terms of knowledge acquisition and retention, satisfaction and engagement of undergraduate medical students during the 6-week obstetrics and gynecology clerkship. MATERIAL AND METHODS: The study was conducted at Karolinska Institutet, a medical university in Sweden, and had a prospective, crossover design. All fifth-year medical students attending the obstetrics and gynecology clerkship, at four different teaching hospitals in Stockholm (approximately 40 students per site), in the Autumn semester of 2022 were invited to participate. Two seminars (one in obstetrics and one in gynecology) were designed and delivered in two different formats, ie TBL and SIL. The student:teacher ratio was approximately 10:1 in the traditional SIL seminars and 20:1 in the TBL. All TBL seminars were facilitated by a single teacher who had been trained and certified in TBL. Student knowledge acquisition and retention were assessed by final examination scores, and the engagement and satisfaction were assessed by questionnaires. For the TBL seminars, individual and team readiness assurance tests were also performed and evaluated. RESULTS: Of 148 students participating in the classrooms, 132 answered the questionnaires. No statistically significant differences were observed between TBL and SIL methods with regard to student knowledge acquisition and retention, engagement and satisfaction. CONCLUSIONS: We found no differences in student learning outcomes or satisfaction using TBL or SIL methods. However, as TBL had a double the student to teacher ratio as compared with SIL, in settings where teachers are scarce and suitable rooms are available for TBL sessions, the method may be beneficial in reducing faculty workload without compromising students' learning outcomes.
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Educación de Pregrado en Medicina , Ginecología , Obstetricia , Ginecología/educación , Humanos , Obstetricia/educación , Educación de Pregrado en Medicina/métodos , Estudios Prospectivos , Femenino , Suecia , Estudios Cruzados , Estudiantes de Medicina/psicología , Aprendizaje Basado en Problemas/métodos , Masculino , Evaluación Educacional , Prácticas Clínicas/métodos , Procesos de Grupo , Adulto , Encuestas y CuestionariosRESUMEN
INTRODUCTION: The mechanism underlying endometriosis-related pain remains poorly understood. Previous studies have indicated that γ-aminobutyric acid (GABA) type A (GABAA ) receptors and GABAergic substances (eg endogenous neurosteroids) play important mechanistic roles in various pain conditions. Our primary objective was to compare GABAA receptor function between women with endometriosis and healthy controls by performing a challenge test with diazepam, a GABAA receptor agonist, using the saccadic eye velocity as the main outcome. The secondary objective was to investigate the relation between GABAA receptor function and serum levels of allopregnanolone, an endogenous positive modulator of the GABAA receptor, in the participating women. MATERIAL AND METHODS: 15 women with pelvic pain and laparoscopically confirmed endometriosis and 10 healthy, symptom-free, control women, aged 18-40 years, underwent the diazepam challenge test during the follicular phase of the menstrual cycle. Basal serum allopregnanolone levels were measured prior to diazepam injection. RESULTS: Compared with healthy controls, women with pelvic pain and confirmed endometriosis had a significantly smaller change in saccadic eye velocity after GABAA receptor stimulation with diazepam, indicating lower sensitivity to diazepam. The saccadic eye velocity response was not correlated with the serum allopregnanolone levels. CONCLUSIONS: Women with painful endometriosis show altered GABAA receptor function, depicted as a muted response to an exogenous GABAA receptor agonist.
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Endometriosis , Receptores de GABA-A , Femenino , Humanos , Receptores de GABA-A/fisiología , Pregnanolona , Ácido gamma-Aminobutírico , Diazepam , Hormonas Esteroides Gonadales , Dolor PélvicoRESUMEN
In this study, we investigate the effect of sexual assault on sexual function in adult women. Participants consisted of 136 women recruited from the Emergency Clinic for Rape Victims in Stockholm. Seventy-three women returned for follow-up six months after the assault and completed the Female Sexual Function Index, assessing their current sexual function compared to that before the assault. A majority (44/73) reported impaired function, which was associated with a simultaneous diagnosis of PTSD (OR 5.7; 95% CI 1.7-19.1, p = .005) or moderate-severe depressive symptoms (OR 4.6; 95% CI 1.6-13.7, p = .006). 27% of women reported improved function.
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Víctimas de Crimen , Violación , Delitos Sexuales , Trastornos por Estrés Postraumático , Adulto , Femenino , Humanos , Factores de Riesgo , Trastornos por Estrés Postraumático/epidemiologíaRESUMEN
INTRODUCTION: Somatization, defined as a number of medically unexplained physical symptoms for many years, is a resource-intensive condition with much suffering. Adult somatization has been linked to childhood trauma in both men and women. Among women, sexual trauma affects somatization level to a greater extent than nonsexual trauma. Early diagnosis of a somatization disorder would be of great help for both patients and society. The purpose of this scoping review is to map and summarize the literature on symptoms within somatization in women who have been sexually abused, and investigate if any specific symptom can be linked to previous sexual abuse. MATERIAL AND METHODS: A scoping review methodology was used. The databases PubMed, PsycINFO, and the Cochrane Library were searched for original qualitative and quantitative research published between 2008 and 2019 that matched the objectives of the review. RESULTS: The database search identified 195 articles, of which 43 were retrieved in full text. Seven articles were included, involving 2076 women. All studies were quantitative. The included studies were heterogeneous. Four studies showed inconsistent findings regarding a link between sexual abuse and chronic or acute pain. Two studies showed an association between sexual abuse and increased incidence of somatic symptoms. One study showed an association between sexual abuse and symptoms of irritable bowel syndrome. No specific somatic symptoms in somatization were identifiable within the scope of this study. CONCLUSIONS: This is to our knowledge the first scoping review on sexual abuse and symptoms of somatization. The findings suggest a link between sexual abuse and somatic symptoms, but the identified association with pain and irritable bowel syndrome is inconsistent. No studies have clearly identified specific symptoms within somatization associated with sexual abuse. Qualitative research on the topic was identified as a knowledge gap.
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Delitos Sexuales/psicología , Trastornos Somatomorfos/psicología , Dolor Crónico/psicología , Femenino , Humanos , Síndrome del Colon Irritable/psicologíaRESUMEN
INTRODUCTION: Active resistance is considered to be the 'normal' reaction during rape. However, studies have indicated that similar to animals, humans exposed to extreme threat may react with a state of involuntary, temporary motor inhibition known as tonic immobility. The aim of the present study was to assess the occurrence of tonic immobility during rape and subsequent post-traumatic stress disorder and severe depression. MATERIAL AND METHODS: Tonic immobility at the time of the assault was assessed using the Tonic Immobility Scale in 298 women who had visited the Emergency clinic for raped women within 1 month of a sexual assault. Information about the assault and the victim characteristics were taken from the structured clinical data files. After 6 months, 189 women were assessed regarding the development of post-traumatic stress disorder and depression. RESULTS: Of the 298 women, 70% reported significant tonic immobility and 48% reported extreme tonic immobility during the assault. Tonic immobility was associated with the development of post-traumatic stress disorder (OR 2.75; 95% CI 1.50-5.03, p = 0.001) and severe depression (OR 3.42; 95% CI 1.51-7.72, p = 0.003) at 6 months. Further, previous trauma history (OR 2.36; 95% CI 1.48-3.77, p < 0.001) and psychiatric treatment history (OR 2.00; 95% CI 1.26-3.19, p = 0.003) were associated with the tonic immobility response. CONCLUSIONS: Tonic immobility during rape is a common reaction associated with subsequent post-traumatic stress disorder and severe depression. Knowledge of this reaction in sexual assault victims is important in legal matters and for healthcare follow up.
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Trastorno Depresivo/psicología , Pérdida de Tono Postural , Violación , Trastornos por Estrés Postraumático/psicología , Adolescente , Adulto , Femenino , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Escalas de Valoración Psiquiátrica , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Introduction: Diabetes in pregnancy is associated with impaired offspring cardiac function. The objective of this systematic review was to determine the effect of diabetes in pregnancy on cardiac function in the offspring measured by echocardiography. Methods: PubMed, Embase, Cochrane CENTRAL and Web of Science databases were searched from 1992 to June 27, 2023. Studies reporting offspring (age < 18 years) cardiac function by echocardiography compared between any type of diabetes in pregnancy and healthy control pregnancies were included. Study selection, quality assessment and risk of bias was independently performed by two reviewers. Meta-analyses was performed where possible. Results: Thirty-one observational studies were included 1,679 cases and 2,694 controls. In the first week of life (23 studies, n = 2,663), intraventricular septum diastolic diameter (hypertrophy) was increased, while myocardial performance index (global function) and LV E/A-ratio (diastolic function) were decreased. No difference was found for left ventricular ejection fraction (systolic function). At 1-6 months (4 studies, n = 454) studies found hypertrophy, and decreased global function, but no difference in systolic or diastolic function. At 1-8 years (7 studies, n = 1,609) no difference was found. The available data did not allow for sub-analysis based on the type of diabetes, treatment, or glycemic control. Conclusions: Diabetes in pregnancy is associated with cardiac hypertrophy and impaired global cardiac function in infants up to six months old. The few studies reporting on older children found no difference in the parameters investigated. Longitudinal studies employing more advanced echocardiographic measures or MRI are needed to evaluate consequences for long-term cardiac health. Systematic Review Registration: https://www.crd.york.ac.uk/, identifier (CRD42022312471).
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This article proposes a more individualized approach to organizational and food safety culture development through the creation of culture change agents. The study used action research with individual therapeutic training of sensory and emotional skills as the action intervention to reveal underlying mechanisms of the culture and create long-term culture change. The study was conducted with a group of voluntary employees over a 3-year period at a department under Food Safety and Veterinary Issues in Danish Agriculture and Food Council. Data was collected using individual in-depth qualitative interviews with a novel questionnaire technique that facilitated participants to bring otherwise unconscious underlying assumptions to awareness. The study found that working intensely and therapeutically on an individual and group level, had a significant impact on the surrounding culture and social capital. Five underlying mechanisms were revealed linking individual culture change to changes in the social capital and culture of the department. Going through the five underlying mechanisms may enable individuals to get to the root causes of issues, facilitate more sharing and collaboration to learn from near-misses and failures, and take action despite facing uncomfortable situations, all important abilities to develop FSC. Based on the underlying mechanisms a 'Change Agent Model' was developed. The model illustrates the important underlying mechanisms that any individual or group can work through to become culture change agents and drivers for organizational culture and FSC development. This is the first of two articles.
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Background: Preterm birth is the leading cause of childhood mortality and morbidity. We aimed to provide a comprehensive systematic review on randomized controlled trials (RCTs) on progesterone, cerclage, pessary, and acetylsalicylic acid (ASA) to prevent preterm birth in asymptomatic women with singleton pregnancies defined as risk of preterm birth and multifetal pregnancies. Methods: Six databases (including PubMed, Embase, Medline, the Cochrane Library) were searched up to February 2022. RCTs published in English or Scandinavian languages were included through a consensus process. Abstracts and duplicates were excluded. The trials were critically appraised by pairs of reviewers. The Cochrane risk-of-bias tool was used for risk of bias assessment. Predefined outcomes including preterm birth, perinatal/neonatal/maternal mortality and morbidity, were pooled in meta-analyses using RevMan 5.4, stratified for high and low risk of bias trials. The certainty of evidence was assessed using the GRADE approach. The systematic review followed the PRISMA guideline. Results: The search identified 2,309 articles, of which 87 were included in the assessment: 71 original RCTs and 16 secondary publications with 23,886 women and 32,893 offspring. Conclusions were based solely on trials with low risk of bias (n = 50).Singleton pregnancies: Progesterone compared with placebo, reduced the risk of preterm birth <37 gestational weeks: 26.8% vs. 30.2% (Risk Ratio [RR] 0.82 [95% Confidence Interval [CI] 0.71 to 0.95]) (high certainty of evidence, 14 trials) thereby reducing neonatal mortality and respiratory distress syndrome. Cerclage probably reduced the risk of preterm birth <37 gestational weeks: 29.0% vs. 37.6% (RR 0.78 [95% CI 0.69 to 0.88]) (moderate certainty of evidence, four open trials). In addition, perinatal mortality may be reduced by cerclage. Pessary did not demonstrate any overall effect. ASA did not affect any outcome, but evidence was based on one underpowered study.Multifetal pregnancies: The effect of progesterone, cerclage, or pessary was minimal, if any. No study supported improved long-term outcome of the children. Conclusion: Progesterone and probably also cerclage have a protective effect against preterm birth in asymptomatic women with a singleton pregnancy at risk of preterm birth. Further trials of ASA are needed. Prevention of preterm birth requires screening programs to identify women at risk of preterm birth. Systematic Review Registration: [https://www.crd.york.ac.uk/prospero/], identifier [CRD42021234946].
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A long-term objective of network medicine is to replace our current, mainly phenotype-based disease definitions by subtypes of health conditions corresponding to distinct pathomechanisms. For this, molecular and health data are modeled as networks and are mined for pathomechanisms. However, many such studies rely on large-scale disease association data where diseases are annotated using the very phenotype-based disease definitions the network medicine field aims to overcome. This raises the question to which extent the biases mechanistically inadequate disease annotations introduce in disease association data distort the results of studies which use such data for pathomechanism mining. We address this question using global- and local-scale analyses of networks constructed from disease association data of various types. Our results indicate that large-scale disease association data should be used with care for pathomechanism mining and that analyses of such data should be accompanied by close-up analyses of molecular data for well-characterized patient cohorts.
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The outer membrane (OM) protects Gram-negative bacteria from harsh environmental conditions and provides intrinsic resistance to many antimicrobial compounds. The asymmetric OM is characterized by phospholipids in the inner leaflet and lipopolysaccharides (LPS) in the outer leaflet. Previous reports suggested an involvement of the signaling nucleotide ppGpp in cell envelope homeostasis in Escherichia coli. Here, we investigated the effect of ppGpp on OM biosynthesis. We found that ppGpp inhibits the activity of LpxA, the first enzyme of LPS biosynthesis, in a fluorometric in vitro assay. Moreover, overproduction of LpxA resulted in elongated cells and shedding of outer membrane vesicles (OMVs) with altered LPS content. These effects were markedly stronger in a ppGpp-deficient background. We further show that RnhB, an RNase H isoenzyme, binds ppGpp, interacts with LpxA, and modulates its activity. Overall, our study uncovered new regulatory players in the early steps of LPS biosynthesis, an essential process with many implications in the physiology and susceptibility to antibiotics of Gram-negative commensals and pathogens.
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We report on the effect of processing, particularly heating, on the digestion dynamics of pea proteins using the standardised semi-dynamic in vitro digestion method. Fractions with native proteins were obtained by mild aqueous fractionation of pea flour. A commercial pea protein isolate was chosen as a benchmark. Heating dispersions of pea flour and mild protein fractions reduced the trypsin inhibitory activity to levels similar to that of the protein isolate. Protein-rich and non-soluble protein fractions were up to 18% better hydrolysed after being thermally denatured, particularly for proteins emptied later in the gastric phase. The degree of hydrolysis throughout the digestion was similar for these heated fractions and the conventional isolate. Further heating of the protein isolate reduced its digestibility as much as 9%. Protein solubility enhances the digestibility of native proteins, while heating aggregates the proteins, which ultimately reduces the achieved extent of hydrolysis from gastro-small intestinal enzymes.
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Proteínas de Guisantes , Digestión , Harina , Tracto Gastrointestinal/metabolismo , Hidrólisis , Proteínas de Guisantes/metabolismoRESUMEN
Currently, food industries typically favour formulation of food products using highly refined techno-functional ingredients of high purity. However, there is a growing interest in less pure techno-functional ingredients with a lower degree of refining as they deliver the same functional properties with reduced environmental impact. We propose that instead of selecting formulations based on purity, they should be selected based on their techno-functional properties. This article illustrates that the shift in perspective may increase the sustainability of food production. The functionality-driven product formulation is explored through a case study in which yellow pea ingredients are selected to increase the viscosity of a salad dressing. The relation between the ingredients (in terms of composition; protein, starch fibre, and a residual fraction) and the final viscosity was quantified and validated using multiple linear regression. The model described the observations well: the final viscosity is mostly dominated by the starch content; protein content has only a marginal impact; and dietary fibre contributes to viscosity with an antagonistic effect with starch. Based on the multiple linear regression model and further formulation optimisation, we identified various combinations of ingredients (with either a high or low degree of refining) that would result in the target final viscosity. An evaluation of the global warming potential of all blends showed that the desired viscosity could be achieved using only isolates, as well as by using only mildly refined fractions. The latter is associated with a global warming potential that is 80% lower than the one based on isolates. This case study demonstrates the proof of concept for this approach, showing it can aid in identifying alternative product formulations with similar techno-functional properties but with a higher sustainability.
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Fibras de la Dieta , Almidón , Condimentos , Industria de Alimentos , ViscosidadRESUMEN
Techno-functional properties of multi-component blends and ingredients are determined by the contribution of each ingredient and the water distribution between those ingredients in the blends. However, ingredients can consist of multiple components, which should be considered to better understand the properties of ingredients and blends thereof. Recently, empirical models were used to describe the viscosity of mildly refined ingredient blends. While many compositions were described well by the empirical models, blends with high fiber contents were not predicted sufficiently well. Therefore, in this research, the multi-component blends of commercial pea protein, pea starch, and pea fiber isolates were investigated on their rheological properties as a function of dry matter content. The same properties were then measured for blends of two of these isolates mixed in different ratios. From the rheological experiments, estimations of the water distribution were made with the polymer blending law. The results were compared with CLSM images. A quantitative analysis of the CLSM images mostly confirmed the model outcomes. The isolate ratio could describe the isolate blends sufficiently well, meaning that it was not necessary to know the exact compositions of the ingredients. It was concluded that changes in meso-structure of the blends, for example a phase transition at high fiber contents, caused the lower predictability by the recently published empirical viscosity models. This study demonstrates that the water distribution in multi-component blends plays a crucial role for their viscoelastic properties and the contribution of the individual isolates and components. Moreover, these polymer blending laws that include water distribution provide extra mechanical insights into the fraction behavior in multi-component blends.
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Vehículos Farmacéuticos , Agua , Reología , Viscosidad , Transición de Fase , Fibras de la Dieta , PolímerosRESUMEN
Collateral sensitivity and resistance occur when resistance development toward one antimicrobial either potentiates or deteriorates the effect of others. Previous reports on collateral effects on susceptibility focus on newly acquired resistance determinants and propose that novel treatment guidelines informed by collateral networks may reduce the evolution, selection, and spread of antimicrobial resistance. In this study, we investigate the evolutionary stability of collateral networks in five ciprofloxacin-resistant, clinical Escherichia coli strains. After 300 generations of experimental evolution without antimicrobials, we show complete fitness restoration in four of five genetic backgrounds and demonstrate evolutionary instability in collateral networks of newly acquired resistance determinants. We show that compensatory mutations reducing efflux expression are the main drivers destabilizing initial collateral networks and identify rpoS as a putative target for compensatory evolution. Our results add another layer of complexity to future predictions and clinical application of collateral networks. IMPORTANCE Antimicrobial resistance occurs due to genetic alterations that affect different processes in bacteria. Thus, developing resistance toward one antimicrobial drug may also alter the response toward others (collateral effects). Understanding the mechanisms of such collateral effects may provide clinicians with a framework for informed antimicrobial treatment strategies, limiting the emergence of antimicrobial resistance. However, for clinical implementation, it is important that the collateral effects of resistance development are repeatable and temporarily stable. Here, we show that collateral effects caused by resistance development toward ciprofloxacin in clinical Escherichia coli strains are not temporarily stable because of compensatory mutations restoring the fitness burden of the initial resistance mutations. Consequently, this instability is complicating the general applicability and clinical implementation of collateral effects into treatment strategies.
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Infecciones por Escherichia coli , Proteínas de Escherichia coli , Antibacterianos/farmacología , Ciprofloxacina/farmacología , Farmacorresistencia Bacteriana/genética , Escherichia coli/metabolismo , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Humanos , Pruebas de Sensibilidad MicrobianaRESUMEN
Rape is the most common trauma leading to post-traumatic stress disorder (PTSD) among women, with a conditioned prevalence of up to 50%. PTSD is considered to be a lethal condition associated with increased risk of suicide, drug- and alcohol dependence, neurological- and vascular problems, as well as sick leave. Given the scope of this problem, novel and swiftly delivered interventions for this large vulnerable population are clearly warranted. One previous trial conducted in the United States (N = 137) showed that an adapted brief version of prolonged exposure (PE) to the fearful memory of the event and situations, provided in the immediate aftermath after trauma (<72 h after a traumatic event), was effective in reducing early PTSD symptoms in rape victims. The aims of the present study were to adapt the brief PE protocol to a Swedish context and investigate its feasibility and delivery in 10 executive patients recruited at the Emergency Clinic for Rape Victims in Stockholm. Ten participants were provided with three sessions of early PE with overall successful results in terms of session attendance, home-work compliance, and also symptom reduction of PTSD and depressive symptoms. However, only a fraction of the screened patients at the Emergency Clinic (5.2%) were eligible to be included in the study, where the majority (40%) were excluded due to the time criteria of 72 h. In this article, we will present detailed results of the intervention and elaborate on how to increase feasibility of preventive interventions for rape victims. In the current form, providing PE with the strict time criteria was not feasible in the clinical setting that constitutes the Emergency Department for rape.
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Plants and insects are key components of terrestrial ecosystems and insect herbivory is the most important type of interaction in these ecosystems. This study presents the first analysis of associations between plants and insects for the early Miocene Hindon Maar fossil lagerstätte, Otago, New Zealand. A total of 584 fossil angiosperm leaves representing 24 morphotypes were examined to determine the presence or absence of insect damage types. Of these leaves, 73% show signs of insect damage; they comprise 821 occurrences of damage from 87 damage types representing all eight functional feeding groups. In comparison to other fossil localities, the Hindon leaves display a high abundance of insect damage and a high diversity of damage types. Leaves of Nothofagus(southern beech), the dominant angiosperm in the fossil assemblage, exhibit a similar leaf damage pattern to leaves from the nearby mid to late Miocene Dunedin Volcano Group sites but display a more diverse spectrum and much higher percentage of herbivory damage than a comparable dataset of leaves from Palaeocene and Eocene sites in the Antarctic Peninsula.
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Pluripotency can be induced in vitro from adult somatic mammalian cells by enforced expression of defined transcription factors regulating and initiating the pluripotency network. Despite the substantial advances over the last decade to improve the efficiency of direct reprogramming, exact mechanisms underlying the conversion into the pluripotent stem cell state are still vaguely understood. Several studies suggested that induced pluripotency follows reversed embryonic development. For somatic cells of mesodermal and endodermal origin that would require the transition through a Primitive streak-like state, which would necessarily require an Eomesodermin (Eomes) expressing intermediate. We analyzed reprogramming in human and mouse cells of mesodermal as well as ectodermal origin by thorough marker gene analyses in combination with genetic reporters, conditional loss of function and stable fate-labeling for the broad primitive streak marker Eomes. We unambiguously demonstrate that induced pluripotency is not dependent on a transient primitive streak-like stage and thus does not represent reversal of mesendodermal development in vivo.