Genetic variation within and among animal populations

2004 ◽  
Vol 30 ◽  
pp. 67-84
Author(s):  
W.G. Hill ◽  
X.-S. Zhang
Keyword(s):  
Quantitative Traits ◽  
Potential Role ◽  
Term Selection ◽  
Animal Populations ◽  
Breeding Programmes ◽  
Simplifying Assumptions ◽  
Commercial Breeding ◽  
Race Horses

AbstractFactors that influence variability between and within populations at levels ranging from the molecular to quantitative traits are reviewed. For quantitative traits, models of how levels of variation are determined and how they change have to be based on simplifying assumptions. At its simplest, variation is maintained by a balance between gain by mutation and loss by sampling due to finite population size. Rates of response in commercial breeding programmes and long-term selection experiments are reviewed. It is seen that rates of progress continue to be high in farmed livestock, but not in race horses, and that continuing responses have been maintained for 100 generations in laboratory experiments. Hence variability can be maintained over long periods despite intense selection in populations of limited size. The potential role of conserved populations is reviewed, and it is suggested that their role is unlikely to be as a useful source of variation in commercial populations but mainly to preserve our culture and to fill particular niches.

Prevention of Cardiac Hypertrophy in Experimental Chronic Renal Failure by Long-Term ACE Inhibitor Administration: Potential Role of Lysosomal Proteinases

1995 ◽  
Vol 15 (2) ◽  
pp. 129-136 ◽  
Author(s):  
Hiroaki Suzuki ◽  
Liliana Schaefer ◽  
Hong Ling ◽  
Roland M. Schaefer ◽  
Jobst Dämmrich ◽  
...  
Keyword(s):  
Renal Failure ◽  
Chronic Renal Failure ◽  
Cardiac Hypertrophy ◽  
Potential Role ◽  
Ace Inhibitor ◽  
Lysosomal Proteinases

scholarly journals Duodenal Dysbiosis and Relation to the Efficacy of Proton Pump Inhibitors in Functional Dyspepsia

2021 ◽  
Vol 22 (24) ◽  
pp. 13609
Author(s):  
Lucas Wauters ◽  
Raúl Y. Tito ◽  
Matthias Ceulemans ◽  
Maarten Lambaerts ◽  
Alison Accarie ◽  
...  
Keyword(s):  
Functional Dyspepsia ◽  
Proton Pump Inhibitors ◽  
Proton Pump ◽  
Potential Role ◽  
Short Term ◽  
Beneficial Effects ◽  
Rrna Sequencing ◽  
Before And After

Proton pump inhibitors (PPI) may improve symptoms in functional dyspepsia (FD) through duodenal eosinophil-reducing effects. However, the contribution of the microbiome to FD symptoms and its interaction with PPI remains elusive. Aseptic duodenal brushings and biopsies were performed before and after PPI intake (4 weeks Pantoprazole 40 mg daily, FD-starters and controls) or withdrawal (2 months, FD-stoppers) for 16S-rRNA sequencing. Between- and within-group changes in genera or diversity and associations with symptoms or duodenal factors were analyzed. In total, 30 controls, 28 FD-starters and 19 FD-stoppers were followed. Mucus-associated Porphyromonas was lower in FD-starters vs. controls and correlated with symptoms in FD and duodenal eosinophils in both groups, while Streptococcus correlated with eosinophils in controls. Although clinical and eosinophil-reducing effects of PPI therapy were unrelated to microbiota changes in FD-starters, increased Streptococcus was associated with duodenal PPI effects in controls and remained higher despite withdrawal of long-term PPI therapy in FD-stoppers. Thus, duodenal microbiome analysis demonstrated differential mucus-associated genera, with a potential role of Porphyromonas in FD pathophysiology. While beneficial effects of short-term PPI therapy were not associated with microbial changes in FD-starters, increased Streptococcus and its association with PPIeffects in controls suggest a role for duodenal dysbiosis after long-term PPI therapy.

scholarly journals Neuroinflammation and Its Impact on the Pathogenesis of COVID-19

2021 ◽  
Vol 8 ◽  
Author(s):  
Mohammed M. Almutairi ◽  
Farzane Sivandzade ◽  
Thamer H. Albekairi ◽  
Faleh Alqahtani ◽  
Luca Cucullo
Keyword(s):  
Immune System ◽  
Molecular Mechanisms ◽  
Potential Role ◽  
Immune Cell ◽  
Clinical Manifestations ◽  
Cell Infiltration ◽  
Cellular Mechanisms ◽  
Cytokine Levels

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The clinical manifestations of COVID-19 include dry cough, difficult breathing, fever, fatigue, and may lead to pneumonia and respiratory failure. There are significant gaps in the current understanding of whether SARS-CoV-2 attacks the CNS directly or through activation of the peripheral immune system and immune cell infiltration. Although the modality of neurological impairments associated with COVID-19 has not been thoroughly investigated, the latest studies have observed that SARS-CoV-2 induces neuroinflammation and may have severe long-term consequences. Here we review the literature on possible cellular and molecular mechanisms of SARS-CoV-2 induced-neuroinflammation. Activation of the innate immune system is associated with increased cytokine levels, chemokines, and free radicals in the SARS-CoV-2-induced pathogenic response at the blood-brain barrier (BBB). BBB disruption allows immune/inflammatory cell infiltration into the CNS activating immune resident cells (such as microglia and astrocytes). This review highlights the molecular and cellular mechanisms involved in COVID-19-induced neuroinflammation, which may lead to neuronal death. A better understanding of these mechanisms will help gain substantial knowledge about the potential role of SARS-CoV-2 in neurological changes and plan possible therapeutic intervention strategies.

scholarly journals Case Report: Clostridium neonatale Bacteremia in a Preterm Neonate With Necrotizing Enterocolitis

2021 ◽  
Vol 9 ◽  
Author(s):  
Nadim Cassir ◽  
Isabelle Grandvuillemin ◽  
Manon Boxberger ◽  
Priscilla Jardot ◽  
Farid Boubred ◽  
...  
Keyword(s):  
Necrotizing Enterocolitis ◽  
Potential Role ◽  
Preterm Neonate ◽  
Gastrointestinal Disorder ◽  
Etiologic Agent ◽  
Preterm Neonates ◽  
Environmental Cleaning ◽  
Life Threatening

Necrotizing enterocolitis is a life-threatening acquired gastrointestinal disorder among preterm neonates and is associated with a high mortality rate and long-term neurodevelopmental morbidity. No etiologic agent has been definitively established; nonetheless, the most implicated bacteria include members of the Clostridium genus. We reported here on a case of Clostridium neonatale bacteremia in a preterm neonate with necrotizing enterocolitis, providing more information regarding the potential role of this bacterium in pathogenesis of necrotizing enterocolitis. We emphasized the sporulating form of C. neonatale that confers resistance to disinfectants usually applied for the hospital environmental cleaning. Further works are needed to establish the causal relationship between the occurrence of NEC and the isolation of C. neonatale, with promising perspectives in terms of diagnostic and therapeutic management.

Radiotherapy after Prostatectomy

2002 ◽  
Vol 88 (6) ◽  
pp. 445-452 ◽  
Author(s):  
Giuseppe Sanguineti ◽  
Paola Franzone ◽  
Laura Culp ◽  
Michela Marcenaro ◽  
Salvina Barra ◽  
...  
Keyword(s):  
High Risk ◽  
Radical Prostatectomy ◽  
Adjuvant Radiotherapy ◽  
Potential Role ◽  
Specific Antigen ◽  
Salvage Treatment ◽  
Salvage Radiotherapy ◽  
Risk Of Failure

Aims and background The role of radiotherapy after prostatectomy is controversial. This paper tries to give some guidelines for everyday practice through an analysis of literature data. Methods The potential role of radiotherapy in the adjuvant and salvage setting is discussed. We also report and interpret available literature data for both settings. Results As regards an increase in or detectable prostate-specific antigen (PSA) after radical prostatectomy, about 40–50% of patients are rendered bNED with local salvage radiotherapy, but only 10–50% are long-term (5 years) biochemically controlled. A timely salvage treatment is crucial to optimize control probability. As regards adjuvant radiotherapy for undetectable postoperative PSA in patients at high risk of failure as judged on pathology, results are more encouraging. Recent data report bNED rates ≥70% at 5 years. Conclusions Although results are far from satisfactory, salvage radiotherapy should be considered for every patient with an increased or detectable PSA after surgery. Adjuvant radiotherapy seems preferable to salvage radiotherapy for patients at high (>30%) risk of failure.

scholarly journals A Study on the Potential Role of Occlusal Fissure Fractures in the Etiopathogenesis of Equine Cheek Teeth Apical Infections

2019 ◽  
Vol 36 (3) ◽  
pp. 171-178 ◽  
Author(s):  
Katherina Y. Wellman ◽  
Padraic M. Dixon
Keyword(s):  
Computed Tomography ◽  
Methylene Blue ◽  
Potential Role ◽  
Histological Study ◽  
Extraction Process ◽  
Dental Tissue ◽  
Rule Out

Thirty-nine equine cheek teeth diagnosed as having anachoretic apical infections and also having occlusal fissure fractures, but without occlusal pulpar exposure, that had been orally extracted without causing occlusal damage and 10 control teeth were used in this study. The teeth were individually imaged by computed tomography, occlusally stained with methylene blue and visually reexamined, then sectioned subocclusally at 5 mm intervals until the fissure fractures could no longer be detected. A limited histological study was then performed on 7 apically infected and 5 control teeth. Standard computed tomography only detected 1 of 39 fissure fractures. Thirteen of the 39 stained teeth had subocclusal fissure fractures visually identified at approximately 6 mm beneath the surface, and in 9 of these 13 teeth the fissure fractures had deeper staining to a level immediately above or into a pulp horn, indicating a potential route for bacterial pulpitis. However, the current study cannot rule out the possibility that the extraction process, long-term formalin storage, or the processing of teeth may have allowed for deeper staining. Additionally, methylene blue may penetrate dental tissue more readily than bacteria can invade. Further studies on the potential role of fissure fractures in the etiopathogenesis of cheek teeth apical infection are warranted.

scholarly journals Biotic Stress-Induced Priming and De-Priming of Transcriptional Memory in Arabidopsis and Apple

Epigenomes ◽  
2019 ◽  
Vol 3 (1) ◽  
pp. 3 ◽  
Author(s):  
Kay Gully ◽  
Jean-Marc Celton ◽  
Alexandre Degrave ◽  
Sandra Pelletier ◽  
Marie-Noelle Brisset ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Potential Role ◽  
Defense Responses ◽  
Pathogen Resistance ◽  
Growth Conditions ◽  
Treatment Level ◽  
Transcriptional Memory ◽  
Pre Treatment

Under natural growth conditions, plants experience various and repetitive biotic and abiotic stresses. Salicylic acid (SA) is a key phytohormone involved in the response to biotic challenges. Application of synthetic SA analogues can efficiently prime defense responses, and leads to improved pathogen resistance. Because SA analogues can result in long-term priming and memory, we identified genes for which expression was affected by the SA analogue and explored the role of DNA methylation in this memorization process. We show that treatments with an SA analogue can lead to long-term transcriptional memory of particular genes in Arabidopsis. We found that subsequent challenging of such plants with a bacterial elicitor reverted this transcriptional memory, bringing their expression back to the original pre-treatment level. We also made very similar observations in apple (Malus domestica), suggesting that this expression pattern is highly conserved in plants. Finally, we found a potential role for DNA methylation in the observed transcriptional memory behavior. We show that plants defective in DNA methylation pathways displayed a different memory behavior. Our work improves our understanding of the role of transcriptional memory in priming, and has important implication concerning the application of SA analogues in agricultural settings.

scholarly journals Cardiac preconditioning with 4-h, 17°C ischemia reduces [Ca2+]i load and damage in part via KATP channel opening

2002 ◽  
Vol 282 (6) ◽  
pp. H1961-H1969 ◽  
Author(s):  
Qun Chen ◽  
Amadou K. S. Camara ◽  
Jianzhong An ◽  
Matthias L. Riess ◽  
Enis Novalija ◽  
...  
Keyword(s):  
Infarct Size ◽  
Potential Role ◽  
K Channel ◽  
Moderate Hypothermia ◽  
Channel Opening ◽  
Cardioprotective Effects ◽  
Hypothermic Storage ◽  
Cardiac Preconditioning

Brief ischemia before normothermic ischemia protects hearts against reperfusion injury (ischemic preconditioning, IPC), but it is unclear whether it protects against long-term moderate hypothermic ischemia. We explored in isolated guinea pig hearts 1) the influence of two 2-min periods of normothermic ischemia before 4 h, 17°C hypothermic ischemia on cardiac cytosolic [Ca2+], mechanical and metabolic function, and infarct size, and 2) the potential role of KATP channels in eliciting cardioprotection. We found that IPC before 4 h moderate hypothermia improved myocardial perfusion, contractility, and relaxation during normothermic reperfusion. Protection was associated with markedly reduced diastolic [Ca2+] loading throughout both hypothermic storage and reperfusion. Global infarct size was markedly reduced from 36 ± 2 (SE)% to 15 ± 1% with IPC. Bracketing ischemic pulses with 200 μM 5-hydroxydecanoic acid or 10 μM glibenclamide increased infarct size to 28 ± 3% and 26 ± 4%, respectively. These results suggest that brief ischemia before long-term hypothermic storage adds to the cardioprotective effects of hypothermia and that this is associated with decreased cytosolic [Ca2+] loading and enhanced ATP-sensitive K channel opening.

The Role of Peritoneal Fibrosis in Encapsulating Peritoneal Sclerosis

2005 ◽  
Vol 25 (4_suppl) ◽  
pp. 48-56 ◽  
Author(s):  
Masanobu Miyazaki ◽  
Yukio Yuzawa
Keyword(s):  
Peritoneal Dialysis ◽  
Collagen Synthesis ◽  
Potential Role ◽  
Curative Treatment ◽  
Peritoneal Fibrosis ◽  
Dialysis Therapy ◽  
Continuous Peritoneal Dialysis

Encapsulating peritoneal sclerosis (EPS) is a serious complication of long-term continuous peritoneal dialysis therapy. The progression of EPS has been classified into four stages by Kawanishi and colleagues: pre-EPS, and the inflammatory, encapsulating, and ileus stages. The key issue is how to diagnose EPS early enough to allow for curative treatment. In this article, we review the mechanisms of peritoneal fibrosis, especially from the perspective of collagen synthesis, and the potential role of that fibrosis in the pathogenesis of EPS.

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