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991.
José-Manuel Cruz Karem Hernández-Lechuga Israel Domínguez-Valle Alejandro Fuentes-Beltrán Javier Ulises Sánchez-Morales Jorge Luis Ocampo-Espindola Carlos Polanco Jean-Claude Micheau Thomas Buhse 《Chirality》2020,32(1):120-134
NaClO3 is achiral in solution. If crystallization is performed under a static set-up, it is recognized that the stochastic nucleation probability results in a racemic mixture of the conglomerate. In this paper, we report a reexamination of the crystallization of NaClO3 from static solution in petri dishes that was conducted over a number of years and is based on the count and analysis of several thousand d- vs. l-NaClO3 crystals. Remarkably, instead of an expected nearly 50/50 coin-tossing situation for the d/l crystal frequency, in most of our experiments a statistically significant bias in favor of d- over l-NaClO3 crystals was found. The experiments also showed that the NaClO3 system was relatively insensitive regarding the intentional addition of a variety of optically active agents. Only in some cases, the persisting d-bias observed in the unseeded experiments slightly increased upon the presence of such additives. Nevertheless, experiments in plastic petri dishes or in presence of fungal spores were able to reverse this bias. A literature survey shows that mainly d-directed non-stochastic behavior in the NaClO3 system has been previously observed in other laboratory settings and by the application of different crystallization techniques. So far, the kind of chiral influence that could be at the origin of the observed bias remains unknown. After the examination of several possible chiral influences of physical, chemical and biological origin, we carefully consider the presence of bio-contaminants as most likely for the cause of this effect. 相似文献
992.
993.
Maria Lucena‐Perez Elena Marmesat Daniel Kleinman‐Ruiz Begoa Martínez‐Cruz Karolina Wcek Alexander P. Saveljev Ivan V. Seryodkin Innokentiy Okhlopkov Mikhail G. Dvornikov Janis Ozolins Naranbaatar Galsandorj Milan Paunovic Mirosaw Ratkiewicz Krzysztof Schmidt Jos A. Godoy 《Molecular ecology》2020,29(4):812-828
Disentangling the contribution of long‐term evolutionary processes and recent anthropogenic impacts to current genetic patterns of wildlife species is key to assessing genetic risks and designing conservation strategies. Here, we used 80 whole nuclear genomes and 96 mitogenomes from populations of the Eurasian lynx covering a range of conservation statuses, climatic zones and subspecies across Eurasia to infer the demographic history, reconstruct genetic patterns, and discuss the influence of long‐term isolation and/or more recent human‐driven changes. Our results show that Eurasian lynx populations shared a common history until 100,000 years ago, when Asian and European populations started to diverge and both entered a period of continuous and widespread decline, with western populations, except Kirov, maintaining lower effective sizes than eastern populations. Population declines and increased isolation in more recent times probably drove the genetic differentiation between geographically and ecologically close westernmost European populations. By contrast, and despite the wide range of habitats covered, populations are quite homogeneous genetically across the Asian range, showing a pattern of isolation by distance and providing little genetic support for the several proposed subspecies. Mitogenomic and nuclear divergences and population declines starting during the Late Pleistocene can be mostly attributed to climatic fluctuations and early human influence, but the widespread and sustained decline since the Holocene is more probably the consequence of anthropogenic impacts which intensified in recent centuries, especially in western Europe. Genetic erosion in isolated European populations and lack of evidence for long‐term isolation argue for the restoration of lost population connectivity. 相似文献
994.
Harini Narayanan Martin F. Luna Moritz von Stosch Mariano Nicolas Cruz Bournazou Gianmarco Polotti Massimo Morbidelli Alessandro Butt Michael Sokolov 《Biotechnology journal》2020,15(1)
In this age of technology, the vision of manufacturing industries built of smart factories is not a farfetched future. As a prerequisite for Industry 4.0, industrial sectors are moving towards digitalization and automation. Despite its tremendous growth reaching a sales value of worth $188 billion in 2017, the biopharmaceutical sector distinctly lags in this transition. Currently, the challenges are innovative market disruptions such as personalized medicine as well as increasing commercial pressure for faster and cheaper product manufacturing. Improvements in digitalization and data analytics have been identified as key strategic activities for the next years to face these challenges. Alongside, there is an emphasis by the regulatory authorities on the use of advanced technologies, proclaimed through initiatives such as Quality by Design (QbD) and Process Analytical Technology (PAT). In the manufacturing sector, the biopharmaceutical domain features some of the most complex and least understood processes. Thereby, process models that can transform process data into more valuable information, guide decision‐making, and support the creation of digital and automated technologies are key enablers. This review summarizes the current state of model‐based methods in different bioprocess related applications and presents the corresponding future vision for the biopharmaceutical industry to achieve the goals of Industry 4.0 while meeting the regulatory requirements. 相似文献
995.
A synopsis of the species of Myxidium Bütschli, 1882 (Myxozoa: Myxosporea: Bivalvulida) is presented. It includes a total of 232 nominal species, whose principal
morphological and morphometric characteristics, site of infection within the host, and original hosts and locality are indicated
in a tabulated format. A diagrammatic illustration of a spore of most of the species is also provided. 相似文献
996.
Cruz Quintana Y Rodríguez Canul R Vidal Martínez VM 《Diseases of aquatic organisms》2011,93(2):141-147
The present study documents the first finding of Panulirus argus Virus 1 (PaV1) in spiny lobster Panulirus argus from Cuba. Samples originated from 2 nursery sites, Matias Keys and Bocas de Alonso Keys, and 2 fishing sites, La Grifa and El Ramajo. Lobsters from the nursery sites (artificial reefs) were collected by SCUBA diving, while those from the fishing sites were collected from artificial shelters known as 'casitas cubanas'. In these shelters it was observed that healthy lobsters tended to avoid infected lobsters. Prevalence of PaV1 in the sampling sites was assessed by using clinical signs such as lethargy, an opaque reddish shell coloration, and milky white hemolymph with loss of clotting activity. The presence of PaV1 was subsequently confirmed by histology and PCR of tissues and hemolymph samples from suspected individuals. Histological sections of the hepatopancreas, gills, gonads, and gut showed infected hemocytes with hypertrophied nuclei and eosinophilic intranuclear Cowdry type A inclusions. A 499 bp band was observed by PCR. The sequence of the amplified fragments was 96% similar to the PaV1 sequence in GenBank. The overall mean prevalence of PaV1 was 4.48% (range: 0 to 9.3%) after pooling the results of the 4 sampling sites. 相似文献
997.
Appleyard CB Cruz ML Isidro AA Arthur JC Jobin C De Simone C 《American journal of physiology. Gastrointestinal and liver physiology》2011,301(6):G1004-G1013
Evidence supports involvement of microflora in the transition of chronic inflammation to neoplasia. We investigated the protective efficacy of the probiotic VSL#3 in a model of colitis-associated colorectal cancer. Chronic colitis was induced in Sprague-Dawley rats by administration of trinitrobenzene sulfonic acid (TNBS), followed 6 wk later by systemic reactivation. To induce colitis-associated dysplasia and cancer, the animals received TNBS (intravenously) twice a week for 10 wk. One group received VSL#3 in drinking water from 1 wk before colitis induction until death. The colons were examined for damage and presence of dysplasia or cancer. Samples were analyzed for cell proliferation and apoptosis, vitamin D receptor (VDR) expression, angiogenic factors, and presence of alkaline sphingomyelinase or phosphatase. Microbial community composition was evaluated by terminal restriction fragment-length polymorphism analysis of the bacterial 16S rRNA gene. None of the probiotic-treated animals developed carcinoma, and no high-grade dysplasia was found in either the proximal or mid colon. In contrast, 29% of the animals in the control group developed carcinoma in one or more regions of the colon. VSL#3-treated animals had significantly less damage than the vehicle treated-controls in all areas of the colon, and this correlated with decreased richness and diversity of the mucosally adherent microbiota. Treatment with the probiotic increased the antiangiogenic factor angiostatin, VDR expression, and alkaline sphingomyelinase. We concluded that pretreatment with the probiotic VSL#3 can attenuate various inflammatory-associated parameters, delaying transition to dysplasia and cancer, thus offering its potential therapeutic use in patients with long-standing colitis. 相似文献
998.
Misawa N Nodate M Otomatsu T Shimizu K Kaido C Kikuta M Ideno A Ikenaga H Ogawa J Shimizu S Shindo K 《Applied microbiology and biotechnology》2011,92(1):147-157
Deposit of useful microorganisms in culture collections requires long-term preservation and successful reactivation techniques.
The goal of this study was to develop a simple preservation protocol for the long-term storage and reactivation of the anammox
biomass. To achieve this, anammox biomass was frozen or lyophilized at two different freezing temperatures (−60°C and in liquid
nitrogen (−200°C)) in skim milk media (with and without glycerol), and the reactivation of anammox activity was monitored
after a 4-month storage period. Of the different preservation treatments tested, only anammox biomass preserved via freezing
in liquid nitrogen followed by lyophilization in skim milk media without glycerol achieved stoichiometric ratios for the anammox
reaction similar to the biomass in both the parent bioreactor and in the freshly harvested control treatment. A freezing temperature
of −60°C alone, or in conjunction with lyophilization, resulted in the partial recovery of the anammox bacteria, with an equal
mixture of anammox and nitrifying bacteria in the reactivated biomass. To our knowledge, this is the first report of the successful
reactivation of anammox biomass preserved via sub-zero freezing and/or lyophilization. The simple preservation protocol developed
from this study could be beneficial to accelerate the integration of anammox-based processes into current treatment systems
through a highly efficient starting anammox biomass. 相似文献
999.