scholarly journals Rotifers in Lake Orta: a potential ecological and evolutionary model system

2016 ◽  
Vol 75 (s2) ◽  
Author(s):  
Stefan Sommer ◽  
Sarma Nandini ◽  
S.S.S. Sarma ◽  
Arpat Ozgul ◽  
Diego Fontaneto

<p>Lake Orta experienced for a few decades a unique history of chronic pollution, with extreme changes in pH and copper concentration. Currently, the lake has recovered to its almost pristine oligotrophic conditions, but its sediments still preserve the record of all the changes that happened since the establishment of the first polluting factories in the 1920s, through to the liming activities in 1989-1990, and to the recovery phase that is still going on. Here we review the current knowledge for Lake Orta regarding rotifers, a diverse component of the zooplankton of the lake, through studies on living organisms and on their resting stages accumulated in the sediments. We also report a brief review of what is known in general on the effects of changes in pH and copper concentration on rotifers at the population, species and community level, providing expectations for such effects on the rotifers of Lake Orta. Then, we conclude our review with a perspective on the potential use of rotifers hatched from the resting stages in the sediment of Lake Orta with the description of experiments that can be performed in the future in the framework of resurrection ecology, in order to understand the mechanisms of past and future changes in the environment.</p>

2017 ◽  
Vol 4 ◽  
pp. 1-53 ◽  
Author(s):  
Paul Murphey ◽  
K.E. Townsend ◽  
Anthony Friscia ◽  
James Westgate ◽  
Emmett Evanoff ◽  
...  

The Bridger Formation is restricted to the Green River Basin in southwest Wyoming, and the Uinta and Duchesne River Formations are located in the Uinta Basin in Utah. These three rock units and their diverse fossil assemblages are of great scientific importance and historic interest to vertebrate paleontologists. Notably, they are also the stratotypes from oldest to youngest for the three middle Eocene North American Land Mammal Ages—the Bridgerian, Uintan, and Duchesnean. The fossils and sediments of these formations provide a critically important record of biotic, environmental, and climatic history spanning approximately 10 million years (49 to 39 Ma). This article provides a detailed field excursion through portions of the Green River and Uinta Basins that focuses on locations of geologic, paleontologic, and historical interest. In support of the field excursion, we also provide a review of current knowledge of these formations with emphasis on lithostratigraphy, biochronology, depositional, and paleoenvironmental history, and the history of scientific exploration.


Author(s):  
Kathryn H. Jacobsen

This chapter discusses the history of and responses to global epidemics of serious diseases. Case studies of cholera, influenza, and HIV/AIDS illustrate typical reactions to pandemic events. The initial stages of a pandemic are often characterized by collective anxiety and a desire for isolation. As the pandemic progresses, there are calls for collective global responses to protect human security and contain outbreaks while maintaining international trade and travel. As pandemics enter a recovery phase, there is often a shift toward the use of advocacy to promote international cooperation, secure continued funding for global health activities, and advance other strategic goals. The rhetoric of pandemics is now being used to describe obesity and other emerging noncommunicable diseases because the language of pandemics connotes risk and demands global action. Pandemics are the result of global interactions and globalization processes, and studies of pandemics are, by definition, global studies.


Genes ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 682
Author(s):  
Matthias Christen ◽  
Nils Janzen ◽  
Anne Fraser ◽  
Adrian C. Sewell ◽  
Vidhya Jagannathan ◽  
...  

A 7-month-old, spayed female, domestic longhair cat with L-2-hydroxyglutaric aciduria (L-2-HGA) was investigated. The aim of this study was to investigate the clinical signs, metabolic changes and underlying genetic defect. The owner of the cat reported a 4-month history of multiple paroxysmal seizure-like episodes, characterized by running around the house, often in circles, with abnormal behavior, bumping into obstacles, salivating and often urinating. The episodes were followed by a period of disorientation and inappetence. Neurological examination revealed an absent bilateral menace response. Routine blood work revealed mild microcytic anemia but biochemistry, ammonia, lactate and pre- and post-prandial bile acids were unremarkable. MRI of the brain identified multifocal, bilaterally symmetrical and T2-weighted hyperintensities within the prosencephalon, mesencephalon and metencephalon, primarily affecting the grey matter. Urinary organic acids identified highly increased levels of L-2-hydroxyglutaric acid. The cat was treated with the anticonvulsants levetiracetam and phenobarbitone and has been seizure-free for 16 months. We sequenced the genome of the affected cat and compared the data to 48 control genomes. L2HGDH, coding for L-2-hydroxyglutarate dehydrogenase, was investigated as the top functional candidate gene. This search revealed a single private protein-changing variant in the affected cat. The identified homozygous variant, XM_023255678.1:c.1301A>G, is predicted to result in an amino acid change in the L2HGDH protein, XP_023111446.1:p.His434Arg. The available clinical and biochemical data together with current knowledge about L2HGDH variants and their functional impact in humans and dogs allow us to classify the p.His434Arg variant as a causative variant for the observed neurological signs in this cat.


Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 299
Author(s):  
Vítor Ennes-Vidal ◽  
Marta Helena Branquinha ◽  
André Luis Souza dos Santos ◽  
Claudia Masini d’Avila-Levy

Calpains are calcium-dependent cysteine peptidases that were originally described in mammals and, thereafter, their homologues were identified in almost all known living organisms. The deregulated activity of these peptidases is associated with several pathologies and, consequently, huge efforts have been made to identify selective inhibitors. Trypanosomatids, responsible for life-threatening human diseases, possess a large and diverse family of calpain sequences in their genomes. Considering that the current therapy to treat trypanosomatid diseases is limited to a handful of drugs that suffer from unacceptable toxicity, tough administration routes, like parenteral, and increasing treatment failures, a repurposed approach with calpain inhibitors could be a shortcut to successful chemotherapy. However, there is a general lack of knowledge about calpain functions in these parasites and, currently, the proteolytic activity of these proteins is still an open question. Here, we highlight the current research and perspectives on trypanosomatid calpains, overview calpain description in these organisms, and explore the potential of targeting the calpain system as a therapeutic strategy. This review gathers the current knowledge about this fascinating family of peptidases as well as insights into the puzzle: are we unable to measure calpain activity in trypanosomatids, or are the functions of these proteins devoid of proteolytic activity in these parasites?


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Victoria Hale ◽  
Maren Weischer ◽  
Jong Y. Park

Although the causes of prostate cancer are largely unknown, previous studies support the role of genetic factors in the development of prostate cancer.CHEK2plays a critical role in DNA replication by responding to double-stranded breaks. In this review, we provide an overview of the current knowledge of the role of a genetic variant, 1100delC, ofCHEK2on prostate cancer risk and discuss the implication for potential translation of this knowledge into clinical practice. Currently, twelve articles that discussedCHEK2∗1100delC and its association with prostate cancer were identified. Of the twelve prostate cancer studies, five studies had independent data to draw conclusive evidence from. The pooled results of OR and 95% CI were 1.98 (1.23–3.18) for unselected cases and 3.39 (1.78–6.47) for familial cases, indicating thatCHEK2∗1100delC mutation is associated with increased risk of prostate cancer. Screening for CHEK2∗1100delC should be considered in men with a familial history of prostate cancer.


2021 ◽  
pp. jim-2020-001659
Author(s):  
Amir Mousapasandi ◽  
Cristan Herbert ◽  
Paul Thomas

Sarcoidosis is a systemic granulomatous disease of unknown etiology and pathogenesis with a heterogeneous clinical presentation. In the appropriate clinical and radiological context and with the exclusion of other diagnoses, the disease is characterized by the pathological presence of non-caseating epithelioid cell granulomas. Sarcoidosis is postulated to be a multifactorial disease caused by chronic antigenic stimulation. The immunopathogenesis of sarcoidosis encompasses a complex interaction between the host, genetic factors and postulated environmental and infectious triggers, which result in granuloma development.The exact pathogenesis of the disease has yet to be elucidated, but some of the inflammatory pathways that play a key role in disease progression and outcomes are becoming apparent, and these may form the logical basis for selecting potential biomarkers.Biomarkers are biological molecules that are altered pathologically. To date, there exists no single reliable biomarker for the evaluation of sarcoidosis, either diagnostically or prognostically but new candidates are emerging. A diagnosis of sarcoidosis ideally requires a biopsy confirming non-caseating granulomas, but the likelihood of progression that requires intervention remains unpredictable. These challenging aspects could be potentially resolved by incorporating biomarkers into clinical practice for both diagnosis and monitoring disease activity.This review outlines the current knowledge on sarcoidosis with an emphasis on pulmonary sarcoidosis, and delineates the understanding surrounding the implication of biomarkers for the clinical evaluation of sarcoidosis.


Stroke ◽  
2016 ◽  
Vol 47 (suppl_1) ◽  
Author(s):  
Ahmed Z Obeidat ◽  
Heidi Sucharew ◽  
Charles J Moomaw ◽  
Dawn O Kleindorfer ◽  
Brett M Kissela ◽  
...  

Background: Current knowledge on ischemic stroke in sarcoid patients stems from sporadic case reports. The mechanism is thought to be related to granulomatous involvement of brain vasculature. However, clinical, demographic, and radiographic features of sarcoid patients with ischemic stroke are lacking. If sarcoid patients are at higher risk for ischemic stroke event, we hypothesized that the risk factors for ischemic stroke and stroke subtype distribution would differ between sarcoid and non-sarcoid ischemic stroke patients. Methods: Cases of ischemic stroke were identified for the years 2005 and 2010 from the population-based Greater Cincinnati/Northern Kentucky Stroke Study (population 1.3 million). Ischemic stroke cases were physician study confirmed and patients with a history of sarcoid were identified through medical chart review. Clinical variables were compared between stroke patients with history of sarcoid and those with no prior sarcoid history. Results: A total of 4258 cases of ischemic stroke were identified; of them, only 18 had prior diagnosis of sarcoid (0.04%). Brain MRI showed diffusion restriction in 14 out of 15 (93%) MRIs performed in sarcoid patients. The table presents risk factor and subtype data on sarcoid patients compared with non-sarcoid patients. Conclusions: We identified only a few cases of prior sarcoid history in our two-year ascertainment of ischemic stroke patients in our population. In comparison with stroke patients with no prior history of sarcoid, the sarcoid patients tended to be of younger age at presentation, female, have a history of diabetes and hyperlipidemia, and more likely of African descent, perhaps related to the diagnosis of sarcoid itself. We were unable to detect differences in stroke subtype distributions between sarcoid and non-sarcoid ischemic stroke patients.


2017 ◽  
Vol 8 (1-IT) ◽  
Author(s):  
Mario Tanga ◽  
Giacomo Gelati ◽  
Marco Casazza

6Contemporary science and culture show more and more extended and meaningful signs about the increasing explaining power of evolutionary paradigm. This power overcomes the field of the history of living species. We consider “On the Origin of Species” of 1859 by Charles Darwin as the establishment of this paradigm, but this original and fruitful idea has received the several and different contributions from near and (seemingly) far scientific fields. This process happened according distinguishable waves and leaded the evolutionary theory very far from its starting point, making it something wider and different. The current knowledge of this theory involves many kinds of scholars: biologists, zoologists, botanists, development biologists, genetics/genomics scholars and also scholars of many other disciplines, as statistics, mathematics, ecology, environmental sciences, physics, chemistry, linguistics, sociology, neuro-sciences, epidemiology, informatics, immunology. During the end of XX Century, the study of complexity, of self-organization and of emerging properties has been a decisive factor to extend evolution until beyond the boundaries of Biology. These phenomena, or properties, or features, that are shown by “living” and “not-living” systems (so called basing ourselves on traditional definitions), have deeply modified even the “properly” biologic evolution itself and besides this has demonstrated that, mutatis mutandis, evolutionary processes or phenomena happen also out of biologic dominion, referring “biologic” to “wet-ware world”. This is to say the class of evolutionary phenomena is more widely and more inclusively extended than our opinion. We can mean this as a revolution (according to Kuhn’s definition) that imposes us to restructure the definition of evolution itself and even to redraw the boundaries and the map of Biology itself. Aiming to establish a name of this field of study we propose “PanEvolutionary Theory” (PanEvo Theory). No doubt Prigogine offered an important contribution to this area. The thinking and the work of Enzo Tiezzi can be placed seen in the same perspective. Disregarding direct connections and contacts with the Nobel Prize Prigogine, however the studies of Enzo Tiezzi are neither a fully unexpected work nor a theory lacking of important potentialities: it is not a strange or eccentric academic exercise. Except the close contact and the dense exchanges with Prigogine, we collocate Enzo Tiezzi in the same context of Gregory Chaitin, of Rachel Carson, of John Harte and Robert H. Socolow, of James Paul Wesley, of Sertorio, of Oort and Peixoto, just to cite the most strictly related. Our Academy had the privilege and the honor of having Enzo Tiezzi in its ranks. We think that merits and developments of the thinking of this scholar have to produce important and lasting fruits in the future.


2020 ◽  
Vol 105 (1) ◽  
pp. 55-66
Author(s):  
Wolfgang Hüttel

Abstract Echinocandins are a clinically important class of non-ribosomal antifungal lipopeptides produced by filamentous fungi. Due to their complex structure, which is characterized by numerous hydroxylated non-proteinogenic amino acids, echinocandin antifungal agents are manufactured semisynthetically. The development of optimized echinocandin structures is therefore closely connected to their biosynthesis. Enormous efforts in industrial research and development including fermentation, classical mutagenesis, isotope labeling, and chemical synthesis eventually led to the development of the active ingredients caspofungin, micafungin, and anidulafungin, which are now used as first-line treatments against invasive mycosis. In the last years, echinocandin biosynthetic gene clusters have been identified, which allowed for the elucidation but also engineering of echinocandin biosynthesis on the molecular level. After a short description of the history of echinocandin research, this review provides an overview of the current knowledge of echinocandin biosynthesis with a special focus of the diverse structural elements, their biosynthetic background, and structure−activity relationships. Key points • Complex and highly oxidized lipopeptides produced by fungi. • Crucial in the design of drugs: side chain, solubility, and hydrolytic stability. • Genetic methods for engineering biosynthesis have recently become available.


2011 ◽  
Vol 50 ◽  
pp. 19-42 ◽  
Author(s):  
Elie Dassa

In recent years, our understanding of the functioning of ABC (ATP-binding cassette) systems has been boosted by the combination of biochemical and structural approaches. However, the origin and the distribution of ABC proteins among living organisms are difficult to understand in a phylogenetic perspective, because it is hard to discriminate orthology and paralogy, due to the existence of horizontal gene transfer. In this chapter, I present an update of the classification of ABC systems and discuss a hypothetical scenario of their evolution. The hypothetical presence of ABC ATPases in the last common ancestor of modern organisms is discussed, as well as the additional possibility that ABC systems might have been transmitted to eukaryotes, after the two endosymbiosis events that led to the constitution of eukaryotic organelles. I update the functional information of selected ABC systems and introduce new families of ABC proteins that have been included recently into this vast superfamily, thanks to the availability of high-resolution three-dimensional structures.


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