scholarly journals Hybridization generates a hopeful monster: a hermaphroditic selfing cichlid

2016 ◽  
Vol 3 (3) ◽  
pp. 150684 ◽  
Author(s):  
Ola Svensson ◽  
Alan Smith ◽  
Javier García-Alonso ◽  
Cock van Oosterhout
Keyword(s):  
Mendelian Inheritance ◽  
Phylogenetic Groups ◽  
Hopeful Monster ◽  
Hybrid Individual ◽  
Novel Traits ◽  
Self Fertilization ◽  
Microsatellite Alleles ◽  
Rule Out

Compared with other phylogenetic groups, self-fertilization (selfing) is exceedingly rare in vertebrates and is known to occur only in one small clade of fishes. Here we report observing one F 1 -hybrid individual that developed into a functional hermaphrodite after crossing two closely-related sexually reproducing species of cichlids. Microsatellite alleles segregated consistent with selfing and Mendelian inheritance and we could rule out different modes of parthenogenesis including automixis. We discuss why selfing is not more commonly observed in vertebrates in nature, and the role of hybridization in the evolution of novel traits.

scholarly journals Effects of Rifaximin on Luminal and Wall-Adhered Gut Commensal Microbiota in Mice

2021 ◽  
Vol 22 (2) ◽  
pp. 500
Author(s):  
Marina Ferrer ◽  
Mònica Aguilera ◽  
Vicente Martinez
Keyword(s):  
Fluorescent In Situ Hybridization ◽  
Fragment Length Polymorphism ◽  
Functional Gastrointestinal Disorders ◽  
Antibacterial Properties ◽  
Broad Spectrum Antibiotic ◽  
Commensal Microbiota ◽  
Bacterial Biodiversity ◽  
Rule Out

Rifaximin is a broad-spectrum antibiotic that ameliorates symptomatology in inflammatory/functional gastrointestinal disorders. We assessed changes in gut commensal microbiota (GCM) and Toll-like receptors (TLRs) associated to rifaximin treatment in mice. Adult C57BL/6NCrl mice were treated (7/14 days) with rifaximin (50/150 mg/mouse/day, PO). Luminal and wall-adhered ceco-colonic GCM were characterized by fluorescent in situ hybridization (FISH) and microbial profiles determined by terminal restriction fragment length polymorphism (T-RFLP). Colonic expression of TLR2/3/4/5/7 and immune-related markers was assessed (RT-qPCR). Regardless the period of treatment or the dose, rifaximin did not alter total bacterial counts or bacterial biodiversity. Only a modest increase in Bacteroides spp. (150 mg/1-week treatment) was detected. In control conditions, only Clostridium spp. and Bifidobacterium spp. were found attached to the colonic epithelium. Rifaximin showed a tendency to favour their adherence after a 1-week, but not 2-week, treatment period. Minor up-regulation in TLRs expression was observed. Only the 50 mg dose for 1-week led to a significant increase (by 3-fold) in TLR-4 expression. No changes in the expression of immune-related markers were observed. Rifaximin, although its antibacterial properties, induces minor changes in luminal and wall-adhered GCM in healthy mice. Moreover, no modulation of TLRs or local immune systems was observed. These findings, in normal conditions, do not rule out a modulatory role of rifaximin in inflammatory and or dysbiotic states of the gut.

scholarly journals Role of the Ser-287-Asn Replacement in the Hydrolysis Spectrum Extension of AmpC β-Lactamases in Escherichia coli

2008 ◽  
Vol 53 (1) ◽  
pp. 323-326 ◽  
Author(s):  
Hedi Mammeri ◽  
Moreno Galleni ◽  
Patrice Nordmann
Keyword(s):  
Escherichia Coli ◽  
Biochemical Characterization ◽  
Catalytic Efficiency ◽  
Phylogenetic Groups ◽  
Extended Spectrum ◽  
Group A

ABSTRACT Two AmpC variants harboring the S287N substitution were obtained by mutagenesis from cephalosporinases representative of the phylogenetic groups A and B2 of Escherichia coli. Their biochemical characterization revealed that the S287N replacement led to an important increase in the catalytic efficiency toward extended-spectrum cephalosporins in the AmpC β-lactamase of group A only.

Narcolepsy: Differential Diagnosis or Etiology in Some Cases of Bipolar Disorder and Schizophrenia?

CNS Spectrums ◽  
2003 ◽  
Vol 8 (2) ◽  
pp. 120-126 ◽  
Author(s):  
Alan B. Douglass
Keyword(s):  
Bipolar Disorder ◽  
Differential Diagnosis ◽  
Psychiatric Patients ◽  
Human Leukocyte ◽  
Sleep Paralysis ◽  
Leukocyte Antigen ◽  
Psychotic Features ◽  
Hypnagogic Hallucinations ◽  
Rule Out

AbstractDoes narcolepsy, a neurological disease, need to be considered when diagnosing major mental illness? Clinicians have reported cases of narcolepsy with prominent hypnagogic hallucinations that were mistakenly diagnosed as schizophrenia. In some bipolar disorder patients with narcolepsy, the HH resulted in their receiving a more severe diagnosis (ie, bipolar disorder with psychotic features or schizoaffective disorder). The role of narcolepsy in psychiatric patients has remained obscure and problematic, and it may be more prevalent than commonly believed. Classical narcolepsy patients display the clinical “tetrad”—cataplexy, hypnagogic hallucinations, daytime sleep attacks, and sleep paralysis. Over 85% also display the human leukocyte antigen marker DQB10602 (subset of DQ6). Since 1998, discoveries in neuroanatomy and neurophysiology have greatly advanced the understanding of narcolepsy, which involves a nearly total loss of the recently discovered orexin/hypocretin (hypocretin) neurons of the hypothalamus, likely by an autoimmune mechanism. Hypocretin neurons normally supply excitatory signals to brainstem nuclei producing norepinephrine, serotonin, histamine, and dopamine, with resultant suppression of sleep. They also project to basal forebrain areas and cortex. A literature review regarding the differential diagnosis of narcolepsy, affective disorder, and schizophrenia is presented. Furthermore, it is now possible to rule out classical narcolepsy in difficult psychiatric cases. Surprisingly, psychotic patients with narcolepsy will likely require stimulants to fully recover. Many conventional antipsychotic drugs would worsen their symptoms and make them appear to become a “chronic psychotic,” while in fact they can now be properly diagnosed and treated.

scholarly journals Inanimate Objects and the Environment Are Far From Contributing to COVID-19 Spread

2021 ◽  
Author(s):  
Ana Luiza Silva Rocha ◽  
Josilene Pinheiro ◽  
Thamilin Costa Nakamura ◽  
José Domingos Santos da Silva ◽  
Beatriz Gonçalves Silva Rocha ◽  
...  
Keyword(s):  
Sampling Method ◽  
Environmental Temperature ◽  
Cell Phones ◽  
Market Area ◽  
P Gene ◽  
Human Rnase ◽  
Reference Hospital ◽  
Market Areas ◽  
Rule Out

Abstract It is not clear if COVID-19 can be indirectly transmitted. It is not possible to conclude the role of environment in transmission of SARS-CoV-2 without studying areas in which people transit in great amounts, such as market areas. In this work we aimed to better understand the role of environment in the spread of COVID-19. We investigated the presence of SARS-CoV-2 in inanimate objects as well as in the air and in the sewage using RT-qPCR. We studied both, a reference market area and a COVID-19 reference hospital at Barreiras city, Brazil. We collected and analyzed a total of 268 samples from mask fronts, cell phones, paper moneys, card machines, sewage, air and bedding during the ascendant phase of the epidemiological curve of COVID-19 in Barreiras. As a result, we detected the human RNAse P gene in most of samples, which indicates the presence of human cells in specimens. However, we did not detect any trace of SARS-CoV-2 in all samples analyzed. To rule out the possibility of problems in sampling method we tested detection of SARS-CoV-2 by RT-qPCR in laboratory conditions to reproduce environmental temperature and humidity. As a result, we showed detection of the virus in different conditions. We conclude that our sampling method reliable and that, strikingly, the environment and inanimate materials do not have an important role in COVID-19 transmission.

scholarly journals Role of Aspirin for primary prevention of cardiovascular and all-cause mortality events in diabetes: An updated meta-analysis of randomized controlled trials.

2021 ◽  
Author(s):  
Hua Ma ◽  
QIng Gu ◽  
Huining Niu ◽  
Xiaohua Li ◽  
Rong Wang
Keyword(s):  
Cardiovascular Disease ◽  
Primary Prevention ◽  
Meta Analysis ◽  
Significant Risk ◽  
Diabetic Patients ◽  
Primary Endpoints ◽  
All Cause Mortality ◽  
Patients With Diabetes ◽  
Rule Out

Background: The use of Aspirin in the primary prevention of cardiovascular disease (CVD) is still a topic of debate, especially in patients with diabetes. The present meta-analysis aims to rule out the efficacy of Aspirin in patients with diabetes and to compare the effectiveness of Aspirin with a placebo (or no treatment) for the primary prevention of CVD and all-cause mortality events in people with diabetes. Materials and Methods: An extensive and systematic search was conducted in Medline (via PubMed), Cinahl (via Ebsco), Scopus, and Web of Sciences from 1988 to December 2020. A detailed literature search was conducted using Aspirin, cardiovascular disease (CVD), diabetes, and efficacy to identify trials of patients with diabetes who received Aspirin for primary prevention of CVD. Demographic details with the primary outcome of events and bleeding outcomes were analyzed. The risk of bias (RoB) in included studies was evaluated using the QUADAS-2 tool. Results: A total of 5 studies out of 13 were included with 23,570 diabetic patients; 11,738 allocated to Aspirin and 11,832 allocated to the placebo group. In patients with diabetes, there was no difference between Aspirin and placebo with respect to the risk of all-cause death with a confidence interval (CI) varying 0.63 to 1.17. In addition, there were no differences in the bleeding outcomes with an odds ratio of 1.4411 (CI 0.47 to 4.34). Conclusion: Aspirin has no significant risk on primary endpoints of cardiovascular events and the bleeding outcomes in diabetic patients compared to placebo. More research on the use of Aspirin alone or in combination with other antiplatelet drugs is required in patients with diabetes to supplement currently available research.

Species Size and Reproductive Economy in Herbaceous Vegetation

2016 ◽  
Author(s):  
Amanda Tracey
Keyword(s):  
Species Coexistence ◽  
Plant Size ◽  
Future Research ◽  
Traditional Theory ◽  
Old Field ◽  
Critical Question ◽  
Self Fertilization ◽  
Reproductive Economy ◽  
Competition For Resources

According to traditional theory, larger plants generaly have an advantage with respect to competition, especially for light. It seems a paradox then that most species that coexist within natural vegetation are relatively small; specis size distributions are right-skewed at virtually every scale. The critical question then becomes: if bigger is better in competition for resources, why then are there so many small plants? A potential explanation for this paradox is that smaller species may have greater reproductive economy-i.e. the ability to reproduce despite suppression from intense competition. Selection for greater reproductive economy may be associated with smaller seed sizes, increased rates of self-fertilization and/or clonality, and in the case of this study, smaller size at reproductive maturity. Random plots in an old field at Queen's University Biological Station were sampled and the largest and smallest reproductive individuals of each species were collected, dried and weighed - to test the hypothesis that smaller species can reproduce at a smaller proportion of their maximum potential plant sizes. The results did not support this, but the hypothesis that smaller plants have greater reproductive economy could not be rejected as it was not possible to record data for the largest possible plant size for each species (since even the largest plants were subjected to competition from neighbours). This provides a focus for future research. Understanding the role of plant size in affecting the process of species assembly has important implications for species coexistence and mechanisms of biodiversity preservation, and thus efforts involving conservation and ecosystem management.

Abstract 19143: Role of Cardiac Biomarkers in Diagnosing Takotsubo Cardiomyopathy from Left Anterior Descending Artery ST Elevation Myocardial Infarction

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Ghulam Akbar ◽  
Marwan Badri ◽  
Catherine Prince ◽  
Wajeeha Saeed ◽  
Ghazi Mirrani ◽  
...  
Keyword(s):  
Coronary Angiography ◽  
Observational Studies ◽  
Troponin I ◽  
Cardiac Biomarkers ◽  
Lv Function ◽  
St Elevation ◽  
Subsequent Improvement ◽  
Echocardiographic Findings ◽  
Rule Out

Introduction: Takostubo cardiomyopathy (TK) and STEMI in the proximal to mid LAD territory (LAD-S) may have similar clinical, ECG and echocardiographic presentation. The two can only be differentiated using coronary angiography. Hypothesis: We hypothesized that the ratio of serum BNP to troponin-I(TnI) will help in distinguishing TK from LAD-S. Previously it has been studied in TK and STEMI from any coronary artery lesion. This is the first study to tease out LAD-S and TK by using BNP/TnI ratio . Methods: We retrospectively compared patients who presented with LAD-S and patients with TK (confirmed with non-obstructive coronary angiography, classic echocardiographic appearance and subsequent improvement of LV function). Patients who did not have BNP and TnI available were excluded. Results: Out of 313 patients with LAD-S and 464 with possible TK, 39 and 62 patients were included respectively. Mean BNP and TnI levels were 788, 57.6ng/dl and 923, 3.4ng/dl in LAD-S and TK respectively. A BNP/TnI ratio of ≤6.4 was 100% sensitive and 41% specific to diagnose LAD-S, and therefore has 100% negative predictive value. A BNP/TnI ratio of ≥2388 was 80% sensitive and 93% specific for diagnosing TK. Conclusion: BNP/TnI ratio <6.4 is reliable to rule out TK and lead to the diagnosis of LAD-S in patients with typical echocardiographic findings. Further, larger observational studies are needed to validate the use of biomarkers for this purpose.

scholarly journals The role of marine mammals in the Barents Sea foodweb

2019 ◽  
Vol 76 (Supplement_1) ◽  
pp. i37-i53 ◽  
Author(s):  
Marie-Anne Blanchet ◽  
Raul Primicerio ◽  
André Frainer ◽  
Susanne Kortsch ◽  
Mette Skern-Mauritzen ◽  
...  
Keyword(s):  
Marine Mammals ◽  
Barents Sea ◽  
Phylogenetic Group ◽  
The Arctic ◽  
Phylogenetic Groups ◽  
Baleen Whales ◽  
Trophic Links ◽  
The Barents Sea ◽  
Network Modularity

Abstract Marine mammals are important players in the Barents Sea ecosystem but their structural role in the foodweb has been little explored. We compare foodweb-related characteristics within and between phylogenetic groups for 19 marine mammals. As a group, they directly connect to the most central species (i.e cod and haddock) in the Barents Sea (i.e. cod and haddock) and consume over half of the available species. Pinnipeds are the most homogenous phylogenetic group with high omnivory and high prey richness. Mysticetes are split between well-connected species with high omnivory like the humpback whale, and peripheral specialists like the blue whale. Based on foodweb-derived indices some species consistently cluster together forming two groups, suggesting topological redundancy within them. One is dominated by Arctic seals and the other includes most of the baleen whales. Marine mammals generally contribute to network modularity as their trophic links are mainly within their own module. However, Atlantic species such as the grey seal act as a module connector decreasing modularity. This might negatively affect ecosystem robustness with perturbation effects spreading further and quicker in the foodweb. In the Arctic reaches of the Barents Sea, climate warming is likely to bring about extensive changes in the foodweb structure through a redistribution of species.

Intracellular pH regulation in rabbit S3 proximal tubule: basolateral Cl-HCO3 exchange and Na-HCO3 cotransport

1990 ◽  
Vol 258 (2) ◽  
pp. F371-F381 ◽  
Author(s):  
N. L. Nakhoul ◽  
L. K. Chen ◽  
W. F. Boron
Keyword(s):  
Proximal Tubule ◽  
Intracellular Ph ◽  
Initial Rate ◽  
Ph Regulation ◽  
Basolateral Membrane ◽  
Intracellular Ph Regulation ◽  
S3 Segment ◽  
Absorbance Spectra ◽  
Rule Out

We studied the role of basolateral HCO3- transport in the regulation of intracellular pH (pHi) in the isolated perfused S3 segment of the rabbit proximal tubule. pHi was calculated from absorbance spectra of the pH-sensitive dye dimethylcarboxyfluorescein. Solutions were normally buffered to pH 7.4 at 37 degrees C with 25 mM HCO3- 5% CO2. pHi fell by approximately 0.17 when luminal [HCO3-] was lowered to 5 mM at fixed PCO2 (i.e., reducing pH to 6.8) but by approximately 0.42 when [HCO3-] in the bath (i.e., basolateral solution) was lowered to 5 mM. The pHi decrease elicited by reducing bath [HCO3-] was substantially reduced by removal of Cl- or Na+, suggesting that components of basolateral HCO3- transport are Cl- and/or Na+ dependent. We tested for the presence of basolateral Cl-HCO3 exchange by removing bath Cl-. This caused pHi to increase by approximately 0.23, with an initial rate of approximately 100 X 10(-4) pH/s. Although the initial rate of this pHi increase was not reduced by removing Na+ bilaterally, it was substantially lowered by the nominal removal of HCO3- from bath and lumen or by the addition of 0.1 mM 4,4'-diisothiocyanostilbene-2,2'-disulfonate (DIDS) to the bath. The results thus suggest that a Na-independent Cl-HCO3 exchanger is present at the basolateral membrane. We tested for the presence of basolateral Na-HCO3 cotransport by removing bath Na+. This caused pHi to fall reversibly by approximately 0.26 with initial rates of pHi decline and recovery being approximately 30 and approximately 41 X 10(-4) pH/s, respectively. Although the bilateral removal of Cl- had no effect on these rates, the nominal removal of HCO3- or the presence of DIDS substantially slowed the pHi changes. Thus, in addition to a Cl-HCO3 exchanger, the basolateral membrane of the S3 proximal tubule also appears to possess a Na-HCO3 cotransport mechanism. The data do not rule out the possibility of other basolateral HCO3- transporters.

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.

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