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1.
EFSA J ; 22(7): e8939, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39050025

RESUMEN

The food enzyme thermolysin (EC. 3.4.24.27) is produced with the non-genetically modified Anoxybacillus caldiproteolyticus strain AE-TP by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in eight food manufacturing processes. Subsequently, the applicant has requested to extend its use to one additional process, to withdraw two processes and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme for use in a total of seven food manufacturing processes. The dietary exposure to the food enzyme-total organic solids (TOS) was calculated to be up to 0.989 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level reported in the previous opinion (700 mg TOS/kg bw per day, the mid-dose tested), the Panel derived a revised margin of exposure of at least 708. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

2.
EFSA J ; 22(7): e8940, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39050021

RESUMEN

The food enzyme oryzin (EC 3.4.21.63) is produced with the non-genetically modified Aspergillus ochraceus strain AE-P by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in nine food manufacturing processes. Subsequently, the applicant has requested to extend its use to one additional process, to withdraw two food processes and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of eight food manufacturing processes. The dietary exposure to the food enzyme-total organic solids (TOS) was calculated to be up to 0.354 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level reported in the previous opinion (1862 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 5260. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

3.
EFSA J ; 22(7): e8944, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39050023

RESUMEN

The food enzyme triacylglycerol lipase (triacylglycerol acylhydrolase; EC 3.1.1.3) is produced with the non-genetically modified Rhizopus arrhizus strain AE-TL(B) by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in two food manufacturing processes. Subsequently, the applicant requested to extend its use to include four additional processes and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of six food manufacturing processes. As the food enzyme-total organic solids (TOS) are removed from one food manufacturing process, the dietary exposure to the food enzyme-TOS was estimated only for the remaining five processes. Dietary exposure was calculated to be up to 0.086 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level reported in the previous opinion (1960 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 22,791. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use.

4.
EFSA J ; 22(7): e8936, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39040571

RESUMEN

The food enzyme lysophospholipase (2-lysophosphatidylcholine acylhydrolase, EC 3.1.1.5) is produced with the genetically modified Trichoderma reesei strain DP-Nyc81 by Genencor International B.V. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. It is intended to be used in the processing of cereals and other grains for the production of glucose syrups and other starch hydrolysates. Since residual amounts of food enzyme-total organic solids are removed during these food manufacturing processes, dietary exposure was not calculated and toxicological studies were considered unnecessary. A search for the identity of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that the risk of allergic reactions upon dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.

5.
Bioessays ; 46(7): e2300238, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38736323

RESUMEN

Genetic mosaicism has long been linked to aging, and several hypotheses have been proposed to explain the potential connections between mosaicism and susceptibility to cancer. It has been proposed that mosaicism may disrupt tissue homeostasis by affecting intercellular communications and releasing microenvironmental constraints within tissues. The underlying mechanisms driving these tissue-level influences remain unidentified, however. Here, we present an evolutionary perspective on the interplay between mosaicism and cancer, suggesting that the tissue-level impacts of genetic mosaicism can be attributed to Indirect Genetic Effects (IGEs). IGEs can increase the level of cellular stochasticity and phenotypic instability among adjacent cells, thereby elevating the risk of cancer development within the tissue. Moreover, as cells experience phenotypic changes in response to challenging microenvironmental conditions, these changes can initiate a cascade of nongenetic alterations, referred to as Indirect non-Genetic Effects (InGEs), which in turn catalyze IGEs among surrounding cells. We argue that incorporating both InGEs and IGEs into our understanding of the process of oncogenic transformation could trigger a major paradigm shift in cancer research with far-reaching implications for practical applications.


Asunto(s)
Carcinogénesis , Mosaicismo , Neoplasias , Humanos , Neoplasias/genética , Neoplasias/patología , Carcinogénesis/genética , Animales , Transformación Celular Neoplásica/genética
6.
J Turk Ger Gynecol Assoc ; 25(1): 1-6, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38444293

RESUMEN

Objective: To evaluate the feasibility of hysteroscopy with morcellator without anesthesia and the diagnostic accuracy of 2D, 3D and power Doppler transvaginal sonography (TVS) in patients with abnormal uterine bleeding (AUB). Material and Methods: This was a retrospective study including women with AUB. All patients underwent 2D, 3D and power Doppler TVS evaluation of the uterine cavity, and patients with suspicion on ultrasound (US) of endometrial pathology (EP) underwent hysteroscopy with morcellator without anesthesia. The painful symptomatology was assessed during the procedure using a visual analogue scale (VAS). Additionally, histological evaluation was performed. Results: A total of 182 women underwent US imaging, of whom 131 (72%) had hysteroscopy. 130/131 patients completed the hysteroscopic examination with good compliance (VAS <4). One patient (0.8%) was unable to complete the procedure due to nulliparity and cervical stenosis. Of the 130 patients the US diagnosis was confirmed in 120 (92.3%), while in 10 patients (7.7%) the hysteroscopic diagnosis was different from the US diagnosis. Histological examination confirmed benign endometrial polyps in 115/130 patients (88.5%), while premalignant conditions were diagnosed in 3/130 patients (2.3%) and malignant conditions in 2/130 (1.5%). Of the 10 patients with endometrial thickening, two were diagnosed with a malignant condition. Conclusion: This study confirmed the feasibility of managing patients with AUB and suspicion of EP using "see-and-treat" hysteroscopy with morcellator without anesthesia. This procedure has the potential to yield desired outcomes while minimizing pain and discomfort, presenting a feasible outpatient approach for both treating and preventing endometrial carcinoma without requiring anesthesia.

7.
Clin Anat ; 37(3): 270-277, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37165994

RESUMEN

Endometriosis is a common benign gynecological disease characterized by the presence of endometrial glands and stroma outside the uterus. It can be defined as endometrioma, superficial peritoneal endometriosis or deep infiltrating endometriosis (DIE) depending on the location and the depth of infiltration of the organs. In 5%-12% of cases, DIE affects the digestive tract, frequently involving the distal part of the sigmoid colon and rectum. Surgery is generally recommended in cases of obstructive symptoms and in cases with pain that is non-responsive to medical treatment. Selection of the most optimal surgical technique for the treatment of bowel endometriosis must consider different variables, including the number of lesions, eventual multifocal lesions, as well as length, width and grade of infiltration into the bowel wall. Except for some major and widely accepted indications regarding bowel resection, established international guidelines are not clear on when to employ a more conservative approach like rectal shaving or discoid resection, and when, instead, to opt for bowel resection. Damage to the pelvic autonomic nervous system may be avoided by detection of the middle rectal artery, where its relationship with female pelvic nerve fibers allows its use as an anatomical landmark. To reduce the risk of potential vascular and nervous complications related to bowel resection, a less invasive approach such as shaving or discoid resection can be considered as potential treatment options. Additionally, the middle rectal artery can be used as a reference point in cases of upper bowel resection, where a trans mesorectal technique should be preferred to prevent devascularization and denervation of the bowel segments not affected by the disease.


Asunto(s)
Endometriosis , Laparoscopía , Enfermedades del Recto , Femenino , Humanos , Recto/cirugía , Endometriosis/cirugía , Endometriosis/complicaciones , Laparoscopía/métodos , Enfermedades del Recto/complicaciones , Enfermedades del Recto/patología , Enfermedades del Recto/cirugía , Resultado del Tratamiento
8.
Minerva Obstet Gynecol ; 75(5): 491-497, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36255159

RESUMEN

Insertion of a LNG-Intra-uterine System (LNG-IUS) has many gynecological indications. The approved indications worldwide are contraception, treatment of abnormal uterine bleeding depending on not organic disease, and endometrial protection in case of an estrogenic therapy. Instead adenomyosis, fibroids, and fertility-sparing management of endometrial hyperplasia or early endometrial cancer in patients with desire of pregnancy are off label indications. Hydroureteronephrosis is an uncommon complication during LNG-IUS insertion. There are few cases described in the literature. The first diagnostic approach for this complication is an abdominal-pelvic ultrasound scan to identify the abnormal position of the device. Diagnostic management includes computed tomography (CT) or magnetic resonance imaging (MRI), which are necessary to confirm hydroureteronephrosis and to assess the exact location of the LNG-IUS in the abdomen. A minimally invasive approach is the standard of care with the removal of the device, while the therapeutic management of the hydroureteronephrosis depends on ureteral and kidney involvement. We report the history of a dislocated LNG-IUS in the left paracervical space with subsequent ipsilateral hydroureteronephrosis. In our case we removed the device through hysteroscopy and later inserted a J-J stent. Follow-up at three months revealed the persistence of left hydroureteronephrosis, so we performed ureter reimplantation. We also performed a review of the literature to analyze common diagnostic and therapeutic pathways for this rare complication.


Asunto(s)
Hiperplasia Endometrial , Neoplasias Endometriales , Dispositivos Intrauterinos Medicados , Embarazo , Femenino , Humanos , Levonorgestrel/uso terapéutico , Dispositivos Intrauterinos Medicados/efectos adversos , Hiperplasia Endometrial/tratamiento farmacológico , Hiperplasia Endometrial/prevención & control , Neoplasias Endometriales/complicaciones , Neoplasias Endometriales/tratamiento farmacológico , Neoplasias Endometriales/prevención & control , Endometrio
9.
Artículo en Inglés | MEDLINE | ID: mdl-36554582

RESUMEN

Many clinical conditions require radiological diagnostic exams based on the emission of different kinds of energy and the use of contrast agents, such as computerized tomography (CT), positron emission tomography (PET), magnetic resonance (MR), ultrasound (US), and X-ray imaging. Pregnant patients who should be submitted for diagnostic examinations with contrast agents represent a group of patients with whom it is necessary to consider both maternal and fetal effects. Radiological examinations use different types of contrast media, the most used and studied are represented by iodinate contrast agents, gadolinium, fluorodeoxyglucose, gastrographin, bariumsulfate, and nanobubbles used in contrast-enhanced ultrasound (CEUS). The present paper reports the available data about each contrast agent and its effect related to the mother and fetus. This review aims to clarify the clinical practices to follow in cases where a radiodiagnostic examination with a contrast medium is indicated to be performed on a pregnant patient.


Asunto(s)
Medios de Contraste , Tomografía Computarizada por Rayos X , Femenino , Embarazo , Humanos , Tomografía Computarizada por Rayos X/métodos , Tomografía de Emisión de Positrones/métodos , Imagen por Resonancia Magnética/métodos , Ultrasonografía
10.
Microorganisms ; 10(10)2022 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-36296178

RESUMEN

The conventionally clear distinction between exons and introns in eukaryotic genes is actually blurred. To illustrate this point, consider sequences that are retained in mature mRNAs about 50% of the time: how should they be classified? Moreover, although it is clear that RNA splicing influences gene expression levels and is an integral part of interdependent cellular networks, introns continue to be regarded as accidental insertions; exogenous sequences whose evolutionary origin is independent of mRNA-associated processes and somewhat still elusive. Here, we present evidence that aids to resolve this disconnect between conventional views about introns and current knowledge about the role of RNA splicing in the eukaryotic cell. We first show that coding sequences flanked by cryptic splice sites are negatively selected on a genome-wide scale in Paramecium. Then, we exploit selection intensity to infer splicing-related evolutionary dynamics. Our analyses suggest that intron gain begins as a splicing error, involves a transient phase of alternative splicing, and is preferentially completed at the 5' end of genes, which through intron gain can become highly expressed. We conclude that relaxed selective constraints may promote biological complexity in Paramecium and that the relationship between exons and introns is fluid on an evolutionary scale.

11.
Front Endocrinol (Lausanne) ; 13: 1014519, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36120472

RESUMEN

Introduction: Adenomyosis is a form of endometriosis characterized by the presence of endometrial tissue in the myometrium. The correlation between anti-Mullerian hormone (AMH) expression and adenomyosis is unclear. Few studies investigated this possible correlation with promising results. The aim of this mini-review is to illustrate the potential prognostic and therapeutic role of AMH in adenomyosis. Materials and methods: A study protocol was completed conforming to the Preferred Reporting Items for Reviews and Meta-Analyses (PRISMA) guidelines for systematic reviews. We performed an electronic databases search from each database's inception from August 2017 to August 2022 for full-text articles and published abstracts. For database searches, the following main keywords were the following text words: "adenomyosis" or "uterine endometriosis" [Mesh] AND "AMH" or "anti-mullerian hormone". Results: From the literature search, 8 abstracts of studies were retrieved and independently screened for inclusion by three authors. It was found that the most common therapeutic strategies (such as adenomyomectomy and high-intensity focused ultrasound (HIFU) do not alter AMH levels. Moreover, a higher expression of the AMH receptor II was observed in adenomyotic tissue, hence a possible therapeutic use of AMH was hypothesized. Conclusion: The available evidence shows an unclear relationship between adenomyosis and AMH. Probably, women with adenomyosis have lower levels of AMH and the surgical treatment (adenomyomectomy, HIFU) does not alter this characteristic, therefore in all of them, ovarian function is not influenced.


Asunto(s)
Adenomiosis , Endometriosis , Hormonas Peptídicas , Adenomiosis/terapia , Hormona Antimülleriana , Endometriosis/terapia , Femenino , Humanos , Pronóstico
12.
Genome Biol Evol ; 13(12)2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34849843

RESUMEN

Mutation accumulation (MA) experiments are conventionally employed to study spontaneous germline mutations. However, MA experiments can also shed light on somatic genome plasticity in a habitual and genetic drift-maximizing environment. Here, we revisit an MA experiment that uncovered extraordinary germline genome stability in Paramecium tetraurelia, a single-celled eukaryote with nuclear dimorphism. Our re-examination of isogenic P. tetraurelia MA lines propagated in nutrient-rich medium for >40 sexual cycles reveals that their polyploid somatic genome accrued hundreds of intervening DNA segments (IESs), which are normally eliminated during germline-soma differentiation. These IESs frequently occupy a fraction of the somatic DNA copies of a given locus, producing IES excision/retention polymorphisms, and preferentially fall into a class of epigenetically controlled sequences. Relative to control lines, retained IESs are flanked by stronger cis-acting signals and interrupt an excess of highly expressed coding exons. These findings suggest that P. tetraurelia's elevated germline DNA replication fidelity is associated with pervasive somatic genome plasticity. They show that MA regimes are powerful tools for investigating the role that developmental plasticity, somatic mutations, and epimutations have in ecology and evolution.


Asunto(s)
Paramecium tetraurelia , Paramecium , ADN Protozoario/genética , Inestabilidad Genómica , Células Germinativas/metabolismo , Humanos , Paramecium/genética , Paramecium tetraurelia/genética , Paramecium tetraurelia/metabolismo
13.
Front Oncol ; 11: 732081, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34568068

RESUMEN

Although neo-Darwinian (and less often Lamarckian) dynamics are regularly invoked to interpret cancer's multifarious molecular profiles, they shine little light on how tumorigenesis unfolds and often fail to fully capture the frequency and breadth of resistance mechanisms. This uncertainty frames one of the most problematic gaps between science and practice in modern times. Here, we offer a theory of adaptive cancer evolution, which builds on a molecular mechanism that lies outside neo-Darwinian and Lamarckian schemes. This mechanism coherently integrates non-genetic and genetic changes, ecological and evolutionary time scales, and shifts the spotlight away from positive selection towards purifying selection, genetic drift, and the creative-disruptive power of environmental change. The surprisingly simple use-it or lose-it rationale of the proposed theory can help predict molecular dynamics during tumorigenesis. It also provides simple rules of thumb that should help improve therapeutic approaches in cancer.

14.
Microorganisms ; 9(9)2021 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-34576874

RESUMEN

Amitosis is a widespread form of unbalanced nuclear division whose biomedical and evolutionary significance remain unclear. Traditionally, insights into the genetics of amitosis have been gleaned by assessing the rate of phenotypic assortment. Though powerful, this experimental approach relies on the availability of phenotypic markers. Leveraging Paramecium tetraurelia, a unicellular eukaryote with nuclear dualism and a highly polyploid somatic nucleus, we probe the limits of single-cell whole-genome sequencing to study the consequences of amitosis. To this end, we first evaluate the suitability of single-cell sequencing to study the AT-rich genome of P. tetraurelia, focusing on common sources of genome representation bias. We then asked: can alternative rearrangements of a given locus eventually assort after a number of amitotic divisions? To address this question, we track somatic assortment of developmentally acquired Internal Eliminated Sequences (IESs) up to 50 amitotic divisions post self-fertilization. To further strengthen our observations, we contrast empirical estimates of IES retention levels with in silico predictions obtained through mathematical modeling. In agreement with theoretical expectations, our empirical findings are consistent with a mild increase in variation of IES retention levels across successive amitotic divisions of the macronucleus. The modest levels of somatic assortment in P. tetraurelia suggest that IESs retention levels are largely sculpted at the time of macronuclear development, and remain fairly stable during vegetative growth. In forgoing the requirement for phenotypic assortment, our approach can be applied to a wide variety of amitotic species and could facilitate the identification of environmental and genetic factors affecting amitosis.

15.
Cancers (Basel) ; 13(9)2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-34063648

RESUMEN

Many aspects of cancer biology remain puzzling, including the proliferative and survival success of malignant cells in spite of their high genetic and epigenetic instability as well as their ability to express migrating phenotypes and/or enter dormancy despite possible fitness loss. Understanding the potential adaptive value of these phenotypic traits is confounded by the fact that, when considered separately, they seem to be rather detrimental at the cell level, at least in the short term. Here, we argue that cancer's biology and success could frequently be governed by processes underlying Parrondo's paradox, whereby combinations of intrinsically losing strategies may result in winning outcomes. Oncogenic selection would favor Parrondo's dynamics because, given the environmental adversity in which malignant cells emerge and evolve, alternating between various less optimal strategies would represent the sole viable option to counteract the changing and deleterious environments cells are exposed to during tumorigenesis. We suggest that malignant processes could be viewed through this lens, and we discuss how Parrondo's principles are also important when designing therapies against cancer.

16.
Bioessays ; 43(6): e2100049, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33829521

RESUMEN

Dietary changes can alter the human microbiome with potential detrimental consequences for health. Given that environment, health, and evolution are interconnected, we ask: Could diet-driven microbiome perturbations have consequences that extend beyond their immediate impact on human health? We address this question in the context of the urgent health challenges posed by global climate change. Drawing on recent studies, we propose that not only can diet-driven microbiome changes lead to dysbiosis, they can also shape life-history traits and fuel human evolution. We posit that dietary shifts prompt mismatched microbiome-host genetics configurations that modulate human longevity and reproductive success. These mismatches can also induce a heritable intra-holobiont stress response, which encourages the holobiont to re-establish equilibrium within the changed nutritional environment. Thus, while mismatches between climate change-related genetic and epigenetic configurations within the holobiont increase the risk and severity of diseases, they may also affect life-history traits and facilitate adaptive responses. These propositions form a framework that can help systematize and address climate-related dietary challenges for policy and health interventions.


Asunto(s)
Rasgos de la Historia de Vida , Microbiota , Cambio Climático , Dieta , Disbiosis , Humanos
17.
Front Cell Dev Biol ; 8: 584219, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33195230

RESUMEN

Unicellular organisms such as ciliates are largely neglected in research on adaptive developmental plasticity, although their nuclear dualism offers ideal circumstances to study development outside an embryonic context. Here, we gain first insights into the ability of the ciliate Paramecium to develop potentially adaptive phenotypic changes in response to early-life adversity. We show that, upon exposure to unconventional culture temperatures, germ line-to-soma differentiation gives rise to coordinated molecular changes that may help attune the number of functional gene copies to the new external conditions. The non-random somatic heterogeneity that developmental plasticity generates is largely epigenetically controlled, shaped by the parental experience, and may prompt a stress response. These findings establish Paramecium as a new model system to study the molecular basis and evolutionary significance of developmental plasticity. In echoing previous indications in mammals, they call for an incorporation of intergenerational effects in adaptation studies.

18.
Genome Biol Evol ; 12(5): 626-638, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32163147

RESUMEN

The pervasiveness of sex despite its well-known costs is a long-standing puzzle in evolutionary biology. Current explanations for the success of sex in nature largely rely on the adaptive significance of the new or rare genotypes that sex may generate. Less explored is the possibility that sex-underlying molecular mechanisms can enhance fitness and convey benefits to the individuals that bear the immediate costs of sex. Here, we show that the molecular environment associated with self-fertilization can increase stress resistance in the ciliate Paramecium tetraurelia. This advantage is independent of new genetic variation, coupled with a reduced nutritional input, and offers fresh insights into the mechanistic origin of sex. In addition to providing evidence that the molecular underpinnings of sexual reproduction and the stress response are linked in P. tetraurelia, these findings supply an integrative explanation for the persistence of self-fertilization in this ciliate.


Asunto(s)
Variación Genética , Paramecium/crecimiento & desarrollo , Paramecium/genética , Autofecundación , Inanición , Animales
19.
Genome Res ; 29(10): 1693-1704, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31548355

RESUMEN

Can ecological changes impact somatic genome development? Efforts to resolve this question could reveal a direct link between environmental changes and somatic variability, potentially illuminating our understanding of how variation can surface from a single genotype under stress. Here, we tackle this question by leveraging the biological properties of ciliates. When Paramecium tetraurelia reproduces sexually, its polyploid somatic genome regenerates from the germline genome through a developmental process that involves the removal of thousands of ORF-interrupting sequences known as internal eliminated sequences (IESs). We show that exposure to nonstandard culture temperatures impacts the efficiency of this process of programmed DNA elimination, prompting the emergence of hundreds of incompletely excised IESs in the newly developed somatic genome. These alternative DNA isoforms display a patterned genomic topography, impact gene expression, and might be inherited transgenerationally. On this basis, we conclude that environmentally induced developmental thermoplasticity contributes to genotypic diversification in Paramecium.


Asunto(s)
Adaptación Fisiológica/genética , ADN Protozoario/genética , Genómica , Paramecium tetraurelia/genética , Animales , Diploidia , Regulación de la Expresión Génica , Reordenamiento Génico/genética , Genoma/genética , Células Germinativas , Paramecium tetraurelia/fisiología
20.
BMC Microbiol ; 18(1): 152, 2018 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-30348081

RESUMEN

BACKGROUND: The airways of the majority of adolescent cystic fibrosis (CF) patients are persistently colonized or infected by Staphylococcus aureus. Using whole genome sequencing, we studied the evolutionary traits within a S. aureus population in the airways of a CF patient hypothesizing that horizontal gene transfer (HGT) and inter-bacterial interaction play a major role in adaptation during long-term persistence. RESULTS: Whole genome sequencing of 21 S. aureus isolates spanning 13 years resulted in seven lineages defined by the spa types t012, t021, t331, t338, t364, t056, and t2351. Of these, the successfully persisting lineages t012 and t021 were closely related suggesting the evolution of t021 from t012, which was further corroborated by a nearly identical, syntenic set of mobile genetic elements. During transformation from t012 to t021, an increase of genomic changes including HGT from other S. aureus lineages was detected. CONCLUSIONS: In summary, our in vivo data enabled us to conceptualize an evolutionary model showing the impact of HGT and inter-bacterial interaction on bacterial long-term adaptation to the human host during CF.


Asunto(s)
Adaptación Fisiológica/genética , Fibrosis Quística/microbiología , Evolución Molecular , Transferencia de Gen Horizontal , Staphylococcus aureus/genética , Humanos , Secuencias Repetitivas Esparcidas , Interacciones Microbianas , Fenotipo , Sistema Respiratorio/microbiología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/crecimiento & desarrollo , Secuenciación Completa del Genoma
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