Repeated insecticide pulses increase harmful effects on stream macroinvertebrate biodiversity and function

2020 ◽  
pp. 116404
Author(s):  
Peter Wiberg-Larsen ◽  
Ulrik Nørum ◽  
Jes Jessen Rasmussen
2021 ◽  
Author(s):  
Keya Li ◽  
Guiying Shi ◽  
Xuepei Lei ◽  
Yiying Huang ◽  
Xinyue Li ◽  
...  

Abstract Background and ObjectivesAdipose-tissue derived stem cells (ADSCs) autologous transplantation have been a promising strategy for aging-related disorder. But the relationship between ADSCs senescence and organismal aging were still no consistent conclusions. Toward this end, we analyzed the senescence properties of ADSCs from different age donors to furthermore understand the differences of cells between young and senile donors and verify the influence of organismal aging on the proliferation and function of ADSCs in vitro, providing the theoretical basis for the clinical application of autologous ADSCs transplantation.Methods and ResultsWe detected the characteristics, function, gene expression, apoptosis, cell cycle, SA-β-gal staining, and transcription features of ADSCs from 1-month mice and 20-month mice. ADSCs from old donors had some senescence-associated changes with less ability to proliferation than ADSCs from 1-month mice. Differentiation ability, cell surface markers, and SA-β-Gal staining did not differ across donor age, while cells exhibit a more remarkable age-related changes through continuous passages. According to the results of transcriptome analysis, the CCL7-CCL2-CCR2 axis and Hippo signaling pathway would be considered as its possible mechanisms. ConclusionsOur study reveals that ADSCs from old donors have some age-related alterations. The CCL7-CCL2-CCR2 which lies behind this change would be a potential target for gene therapy to reduce harmful effects of ADSCs from old donors. To make autologous transplantation work better, we would recommend that ADSCs should be cryopreserved in youth with minimum number of passages.


2020 ◽  
Vol 9 (2) ◽  
pp. 471 ◽  
Author(s):  
Francesco Pallotti ◽  
Marianna Pelloni ◽  
Daniele Gianfrilli ◽  
Andrea Lenzi ◽  
Francesco Lombardo ◽  
...  

Great attention has been paid in recent years to the harmful effects of various chemicals that interfere with our natural hormone balance, collectively known as endocrine-disrupting chemicals (EDCs) or endocrine disruptors. The effects on the reproductive system of bisphenol A (BPA) and phthalates have received particular attention: while they have a short half-life, they are so widespread that human exposure can be considered as continuous. Evidence is often limited to the animal model, disregarding the likelihood of human exposure to a mixture of contaminants. Data from animal models show that maternal exposure probably has harmful effects on the male fetus, with an increased risk of urogenital developmental abnormalities. After birth, exposure is associated with changes in the hypothalamic-pituitary-testicular axis, hindering the development and function of the male genital pathways through the mediation of inflammatory mechanisms and oxidative stress. The epidemiological and clinical evidence, while generally confirming the association between reproductive abnormalities and some phthalate esters and BPA, is more contradictory, with wildly different findings. The aim of this review is therefore to provide an update of the potential mechanisms of the damage caused by BPA and phthalates to reproductive function and a review of the clinical evidence currently available in the literature.


2021 ◽  
Vol 9 (12) ◽  
pp. 540-552
Author(s):  
Saad Fahad Aldaihani

Vitamins are a heterogeneous group of organic compounds that help ensure the human bodys wellbeing and function. This paper introduces the importance of all vitamins, both water-soluble and fat-soluble, as well as problems deriving from their deficiency. Additionally, vitamin supplements as part of treating vitamin deficiency, and possible harmful effects on the human body areshowcased. The main focus of the paper is on the vitamin B complex, and vitamin B12 specifically. The benefits of vitamin B12, as well as its action in the human body and the noxious effects of any lack of vitamin B12 in the human body, are also discussed. Some of the health conditionsan individual may need to face when they have vitamin B12 deficiency include neural tube defects, Alzheimers disease, depression, and megaloblastic anaemia, which are also introduced and further discussed, in terms of symptomatology, causes and suggested treatment. The toxicity of vitamin B12 is also introduced, and possible causes for vitamin B12 deficiency are showcased.


2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Kevin Anthony ◽  
Katie Robinson ◽  
Philippa Logan ◽  
Adam L. Gordon ◽  
Rowan H. Harwood ◽  
...  

Introduction. Frail older people are often unable to undertake high-intensity exercise programmes. Chair-based exercises (CBEs) are used as an alternative, for which health benefits are uncertain.Objective. To examine the effects of CBE programmes for frail older people through a systematic review of existing literature.Method. A systematic search was performed for CBE-controlled trials in frail populations aged ≥65 years published between 1990 and February 2011 in electronic databases. Quality was assessed using the Jadad method.Results. The search identified 164 references: with 42 duplicates removed, 122 reviewed, 116 excluded, and 6 analysed. 26 outcome measures were reported measuring 3 domains: mobility and function, cardiorespiratory fitness, mental health. All studies were of low methodological quality (Jadad score ≤2; possible range 0–5). Two studies showed no benefit, and four reported some evidence of benefit in all three domains. No harmful effects were reported; compliance was generally good.Conclusion. The quality of the evidence base for CBEs is low with inconclusive findings to clearly inform practice. A consensus is required on the definition and purpose of CBEs. Large well-designed randomised controlled trials to test the effectiveness of CBE are justified.


Biomolecules ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 768
Author(s):  
Stefanos Roumeliotis ◽  
Evangelia Dounousi ◽  
Marios Salmas ◽  
Theodoros Eleftheriadis ◽  
Vassilios Liakopoulos

One of the main limitations to successful long-term use of peritoneal dialysis (PD) as a renal replacement therapy is the harmful effects of PD solutions to the structure and function of the peritoneal membrane (PM). In PD, the PM serves as a semipermeable membrane that, due to exposure to PD solutions, undergoes structural alterations, including peritoneal fibrosis, vasculopathy, and neoangiogenesis. In recent decades, oxidative stress (OS) has emerged as a novel risk factor for mortality and cardiovascular disease in PD patients. Moreover, it has become evident that OS plays a pivotal role in the pathogenesis and development of the chronic, progressive injury of the PM. In this review, we aimed to present several aspects of OS in PD patients, including the pathophysiologic effects on the PM, clinical implications, and possible therapeutic antioxidant strategies that might protect the integrity of PM during PD therapy.


Author(s):  
M. Boublik ◽  
W. Hellmann ◽  
F. Jenkins

The present knowledge of the three-dimensional structure of ribosomes is far too limited to enable a complete understanding of the various roles which ribosomes play in protein biosynthesis. The spatial arrangement of proteins and ribonuclec acids in ribosomes can be analysed in many ways. Determination of binding sites for individual proteins on ribonuclec acid and locations of the mutual positions of proteins on the ribosome using labeling with fluorescent dyes, cross-linking reagents, neutron-diffraction or antibodies against ribosomal proteins seem to be most successful approaches. Structure and function of ribosomes can be correlated be depleting the complete ribosomes of some proteins to the functionally inactive core and by subsequent partial reconstitution in order to regain active ribosomal particles.


Author(s):  
S. K. Pena ◽  
C. B. Taylor ◽  
J. Hill ◽  
J. Safarik

Introduction: Oxidized cholesterol derivatives have been demonstrated in various cell cultures to be very potent inhibitors of 3-hvdroxy-3- methylglutaryl Coenzyme A reductase which is a principle regulator of cholesterol biosynthesis in the cell. The cholesterol content in the cells exposed to oxidized cholesterol was found to be markedly decreased. In aortic smooth muscle cells, the potency of this effect was closely related to the cytotoxicity of each derivative. Furthermore, due to the similarity of their molecular structure to that of cholesterol, these oxidized cholesterol derivatives might insert themselves into the cell membrane, alter membrane structure and function and eventually cause cell death. Arterial injury has been shown to be the initial event of atherosclerosis.


Author(s):  
Caroline A. Miller ◽  
Laura L. Bruce

The first visual cortical axons arrive in the cat superior colliculus by the time of birth. Adultlike receptive fields develop slowly over several weeks following birth. The developing cortical axons go through a sequence of changes before acquiring their adultlike morphology and function. To determine how these axons interact with neurons in the colliculus, cortico-collicular axons were labeled with biocytin (an anterograde neuronal tracer) and studied with electron microscopy.Deeply anesthetized animals received 200-500 nl injections of biocytin (Sigma; 5% in phosphate buffer) in the lateral suprasylvian visual cortical area. After a 24 hr survival time, the animals were deeply anesthetized and perfused with 0.9% phosphate buffered saline followed by fixation with a solution of 1.25% glutaraldehyde and 1.0% paraformaldehyde in 0.1M phosphate buffer. The brain was sectioned transversely on a vibratome at 50 μm. The tissue was processed immediately to visualize the biocytin.


Author(s):  
J. Metz ◽  
M. Merlo ◽  
W. G. Forssmann

Structure and function of intercellular junctions were studied under the electronmicroscope using conventional thin sectioning and freeze-etch replicas. Alterations of tight and gap junctions were analyzed 1. of exocrine pancreatic cells under cell isolation conditions and pancreatic duct ligation and 2. of hepatocytes during extrahepatic cholestasis.During the different steps of cell isolation of exocrine pancreatic cells, gradual changes of tight and gap junctions were observed. Tight junctions, which formed belt-like structures around the apex of control acinar cells in situ, subsequently diminished, became interrupted and were concentrated into macular areas (Fig. 1). Aggregations of membrane associated particles, which looked similar to gap junctions, were intermixed within tight junctional areas (Fig. 1). These structures continously disappeared in the last stages of the isolation procedure. The intercellular junctions were finally separated without destroying the integrity of the cell membrane, which was confirmed with porcion yellow, lanthanum chloride and horse radish peroxidase.


Author(s):  
M. Boublik ◽  
R.M. Wydro ◽  
W. Hellmann ◽  
F. Jenkins

Ribosomes are ribonucleoprotein particles necessary for processing the genetic information of mRNA into proteins. Analogy in composition and function of ribosomes from diverse species, established by biochemical and biological assays, implies their structural similarity. Direct evidence obtained by electron microscopy seems to be of increasing relevance in understanding the structure of ribosomes and the mechanism of their role in protein synthesis.The extent of the structural homology between prokaryotic and eukaryotic ribosomes has been studied on ribosomes of Escherichia coli (E.c.) and Artemia salina (A.s.). Despite the established differences in size and in the amount and proportion of ribosomal proteins and RNAs both types of ribosomes show an overall similarity. The monosomes (stained with 0.5% aqueous uranyl acetate and deposited on a fine carbon support) appear in the electron micrographs as round particles with a diameter of approximately 225Å for the 70S E.c. (Fig. 1) and 260Å for the 80S A.s. monosome (Fig. 2).


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