bluuebunny/crossref_metadata_2025_split huggingface dataset:
Growth of mammalian cells at high oxygen concentrations
Authors: Oller A. R. , Buser C. W. , Tyo M. A. , Thilly W. G. 
Published: April 2021

ABSTRACT
Oxygen, although essential to the growth of mammalian cells in vitro and in vivo, has been widely reported to be toxic at concentrations at or above the oxygen concentration in culture medium equilibrated with air (approximately 200 μM). We were therefore surprised to note that a diploid human B-cell line (TK6) was able to proliferate normally while exposed to 380 μM-oxygen. This observation was extended to Veto (African Green monkey kidney) cells, and Sp2/0-derived murine transfectomas producing antibody. Using an experimental system with a high capacity for oxygen transfer, we determined the growth rates of the three cell lines at controlled oxygen concentrations ranging from 80 μM to 910 μM. Each of these cell types was able to grow normally at oxygen concentrations up to 360-380 μM. At oxygen concentrations above 380 μM, a significant increase in the apparent doubling times of the cells was observed. No adverse effect of oxygen on TK6 cell survival was seen for concentrations ranging from 60 fOA to 410 μM. We conclude that exponential growth at nearly maximum growth rates was observed for Sp2/0-derived cells, TK6, and Vero cells at constant oxygen concentrations up to 400 μM (twice air saturation).
These findings have substantial implications for process control in the production of cells and cell-derived materials. The intrinsic oxygen transfer rate of any cell culture vessel can be increased severalfold by raising the oxygen gas concentration. In practice, this should permit significant increases in the operating cell density without the difficulty and expense of oxygen control feedback loops. Using this information it should be possible to eliminate oxygen transfer as a limiting factor in high-density cell culture technology.
The role of the cytoskeleton in positioning of the nucleus in premitotic tobacco BY-2 cells
Authors: Katsuta Junko , Hashiguchi Yuki , Shibaoka Hiroh 
Published: April 2021

ABSTRACT
In premitotic tobacco BY-2 cells, the nucleus moves from the periphery to the central region of the cell and settles there. This premitotic migration of the nucleus occurs in the presence of aphidicolin, an inhibitor of DNA polymerase α, which suppresses the formation of the preprophase band of microtubules (PPB). Thus, the formation of the PPB is not a prerequisite for this premitotic nuclear migration. Tethered by transvacuolar cytoplasmic strands, which contain both microtubules and actin filaments, the nucleus migrates to the site of future division. This migration is not prevented by disruption of actin filaments caused by treatment with cytochalasin, suggesting that microtubules play an important role in the premitotic migration of the nucleus.
In the preprophase cell, microtubules were present in the PPB and in cytoplasmic strands, which extended from the nucleus to the periphery of the cell near the PPB and near the poles, and which were associated with actin filaments. At the end of prophase, microtubules in the cytoplasmic strands and the PPB disappeared, leaving actin filaments in the transvacuolar cytoplasmic strands. Thereafter, the position of the mitotic apparatus (or that of the cytokinetic phragmoplast) was maintained by cytoplasmic strands that contained only actin filaments. The disruption of microtubules by treatment with propyzamide prevented the formation of the PPB-like band of actin filaments, as well as that of the PPB itself. From these results, we propose the following hypothesis. In premitotic tobacco BY-2 cells, microtubules change their arrangement irrespective of the presence of actin filaments. The resultant premitotic network of microtubules serves as a scaffold for building up the mitotic network of actin filaments, which plays an important role in maintaining the position of the mitotic apparatus and in controlling the direction of expansion of the phragmoplast.
Evidence for membrane differentiation in polarised leucocytes: the distribution of surface antigens analysed with lg–gold labelling
Authors: Haston W. S. , Maggs A. F. 
Published: April 2021

ABSTRACT
The distribution of a number of leucocyte surface antigens was studied on both round and polarised neutrophil or mononuclear leucocytes using Ig-gold conjugates with transmission electron microscopy. Thin sections of cells, which had been lightly fixed before antibody labelling, were analysed using a statistical method to determine: (1)whether the antigens had a non-random distribution or ‘clustering’ over the cell surface; and (2)whether there was any overall bias in labelling to give a polarised distribution. Comparison between the results of this analysis and cell morphology were made. The results indicated that with the antigens investigated here, CD45, CD15, HLA-DR and CR3, the majority of polarised cells had a calculated direction of overall asymmetry of gold particles that was aligned with the long axis of morphological polarity. Maximal asymmetry was seen in polarised cells labelled for CD45 and HLA-DR, with labelling ratios of up to 6:1 between the front and back of the cell. A number of round mononuclear cells demonstrated significant polarisation of gold particles but this had no apparent morphological correlation and, in general, round cells showed a low degree of asymmetry. However, there was evidence that both round and polarised cells had a non-random distribution or ‘clustering’ of gold particles, which was more marked in morphologically polarised cells and particularly significant in polarised neutrophil leucocytes labelled for CR3.
The significance of these results for models of cell locomotion involving membrane flow is discussed.
Polymorphonuclear leukocyte phagocytosis of Capnocytophaga ochracea in three-dimensional plasma clots
Authors: Hurst T. J. , Wilton J. M. A. 
Published: April 2021

ABSTRACT
We have studied the ability of human polymorphonuclear leukocytes (PMN) to phagocytose Capnocytophaga ochracea in three-dimensional fibrin meshworks. Phagocytosis was assessed in three systems: (1) the PMN and bacteria were mixed together with plasma and clotted; 60±13% phagocytosis occurred after 60 min; (2) PMN were overlaid on clots containing bacteria; the PMN migrated into the clot and after 60 min 52±7% phagocytosis was seen; (3) PMN had to migrate from within one clot into a second containing bacteria; phagocytosis after 60 min was 54±3 %. In the clots, PMN released lysozyme but this was not significantly enhanced by phagocytosis. These findings indicate that PMN are capable of phagocytosing in each of the threedimensional systems tested and that they are capable of both migration into and subsequent phagocytosis in a model that more closely mimics the in vivo structure in which PMN would normally perform.
Role of membrane phosphotyrosine proteins in human spermatozoa! function
Authors: Naz Rajesh K. , Ahmad Khaliq , Kumar Rakesh 
Published: April 2021

ABSTRACT
The monoclonal anti-phosphotyrosine antibody (PTA) recognized proteins related to relative molecular mass regions of 94 000±3000 and 46 000±3000 Mr on Western blots of detergent-solubilized non-capacitated human sperm extract (HSE). The pattern of phosphorylation at tyrosine residues depended upon the physiological state of the sperm cells. At least six protein bands corresponding to four molecular regions of 94 000±3000, 46 000 ±3000, 25 000 ± 7000 and 12 000±2000Afr, respectively, were labeled with 32P when human sperm were capacitated in vitro-, the proteins belonging to the former three regions were phosphotyrosine proteins as they were precipitable by PTA. In vitro kinase assay performed directly on HSE indicated autophosphorylation of proteins of the same four molecular regions, with the capacitated sperm preparations having 30% higher 32P incorporation into 94 000±3000Mr proteins and 17% less incorporation into 12 000±2000Mr proteins as compared to the non-capacitated sperm preparations. Both of these protein regions were also autophosphorylated at tyrosine residues when immunoprecipitated phosphotyrosine proteins were used for the kinase assay. Phosphorylation of tyrosine residues of 94 000 ± 3000 Mr proteins was further stimulated by 1.38- to 1.46-fold in response to exposure to zona pellucida proteins, namely the porcine ZP3 and human zona proteins (HZP); the HZP induced the highest response. Immunofluorescence observations on fixed human sperm demonstrated that capacitation as well as exposure to zona proteins increased the degree of tyrosine-specific fluorescence per sperm cell as well as the number of sperm cells that showed fluorescence at the acrosomal region of the spermhead. PTA showed a significant (P&lt;0.001) inhibition of human sperm binding and penetration of zona-free hamster eggs. These results indicate that the human sperm membrane proteins are phosphorylated at tyrosine residues during capacitation, and the degree of autophosphorylation of 94 000±3000Mr proteins increases after exposure to zona proteins, implying a vital role for tyrosine phosphorylation in the development of the fertilizing capacity of human sperm cells.
Monoclonal antibodies to Leishmania mexicana promastigote antigens II. Cellular localization of antigens in promastigotes and infected macrophages
Authors: Stierhof York-Dieter , Schwarz Heinz , Menz Beatrice , Russell David G. , Quinten Margret , Overath Peter 
Published: April 2021

ABSTRACT
In the accompanying paper by IIg et al., it was shown that Leishmania mexicana promastigotes covalently modify a secreted acid phosphatase and other proteins by carbohydrate epitopes characteristic for lipophosphoglycan (LPG). In this study, the reaction of the anti-LPG monoclonal antibodies (mAbs AP3 and L7.25) and of mAb L3.13, an antibody directed against an epitope present on the secreted acid phosphatase but not on LPG, with promastigotes and infected peritoneal macrophages is studied by immunofluorescence and immunoelectron microscopy. AP3 labels the surface, the flagellar pocket and intracellular structures in promastigotes, while L3.13 reacts predominantly with an antigen located in the flagellar pocket Early after infection with promastigotes, but not amastigotes, AP3 or L7.25 transiently label epitopes at the surface of live macrophages. No L3.13-reactive material is detected at the surface of infected macrophages. In permeabilized, infected macrophages, AP3 heavily labels the surface of amastigotes and the lumen of the parasitophorous vacuole, while L3.13 reveals antigen in the flagellar pocket, intracellular vesicles of amastigotes, and components in the lumen of the parasitophorous vacuole. Possible mechanistic implications for Leish- marua-macrophage interaction raised by these findings are discussed.
Blue Stentorin.—The Colouring Matter of Stentor Cæruleus
Authors: Lankester E. Ray 
Published: April 2021

ABSTRACT
In the spring of 1871, when I was staying at Jena, a small aquarium tank belonging to Professor Haeckel was swarming with Stentor cceruleus. I had often thought that the peculiar blue tint of this infusorian was likely to give a detached absorption band or bands, and was, therefore, glad of the opportunity of examining its effect on the spectrum by means of the Sorby-Browning micro-spectroscope. I need hardly point out here that it is only by means of the application of the spectroscope to the microscope that the colouring matter of so minute ail Organism as a Stentor could be examined. I succeeded in bringing the instrument to bear on single specimens of the Stentor placed on a glass slip and covered in the usual way with a thin glass cover. But my observations were greatly facilitated by the presence in the tank which contained the Stentors of a number of Chœtogaster diaphanus. Many of these worms had gorged themselves with Stentor cœruleus, and their stomachs were distended with the blueish-green undigested bodies of these Infusoria. In fact the Clnctogasters had acted as most excellent collectors of the material I wished to examine, and on account of their perfect transparency I was able to make use of the Stentors packed in their stomachs just as they were, in order to obtain a greater mass of the colouring matter through which to pass the light before submitting it to spectrum analysis.
On Double Staining Nucleated Blood-Corpuscles with Anilin Dyes
Authors: Harris Vincent 
Published: April 2021

ABSTRACT
The usefulness of the process of staining tissues with several dyes has been abundantly proved. The general effect aimed at is the staining of each separate part in a different colour, so that for the purposes of histological demonstration each shall be distinct and clear. In the use of certain of the most commonly employed and easily manipulated dyes, e. g. hematoxylin and picrocarmine, it is believed that a definite effect may be always calculated upon when they are used in combination. With anilin stains, however, the results arrived at appear to differ very materially if the methods of employment are made to vary in even a very slight degree, and this has been one of the causes of the restricted use of very beautiful staining colours. It has been shown by several experimenters that with combinations of anilin colours, there is a tendency at any rate for certain dyes to pick out and stain different parts of a tissue; but I think I am right in believing that no certain result has hitherto been expected, except in the case of a very few combinations.
Note on a Minute Point in the Structure of the Spermatozoon of the Newt.
Authors: Dowdeswell G. F. 
Published: April 2021

ABSTRACT
The general structure of the spermatozoon of the water Newt (Triton cristalus) has recently been well and accurately described by Dr. H. Gibbes in this Journal.1 It is to a point therein, which has hitherto escaped notice, that I wish here to call attention.
Adult neurogenesis in the central nervous system of teleost fish: from stem cells to function and evolution
Authors: Zupanc Günther K. H. 
Published: April 2021

ABSTRACTAdult neurogenesis, the generation of functional neurons from adult neural stem cells in the central nervous system (CNS), is widespread, and perhaps universal, among vertebrates. This phenomenon is more pronounced in teleost fish than in any other vertebrate taxon. There are up to 100 neurogenic sites in the adult teleost brain. New cells, including neurons and glia, arise from neural stem cells harbored both in neurogenic niches and outside these niches (such as the ependymal layer and parenchyma in the spinal cord, respectively). At least some, but not all, of the stem cells are of astrocytic identity. Aging appears to lead to stem cell attrition in fish that exhibit determinate body growth but not in those with indeterminate growth. At least in some areas of the CNS, the activity of the neural stem cells results in additive neurogenesis or gliogenesis – tissue growth by net addition of cells. Mathematical and computational modeling has identified three factors to be crucial for sustained tissue growth and correct formation of CNS structures: symmetric stem cell division, cell death and cell drift due to population pressure. It is hypothesized that neurogenesis in the CNS is driven by continued growth of corresponding muscle fibers and sensory receptor cells in the periphery to ensure a constant ratio of peripheral versus central elements. This ‘numerical matching hypothesis’ can explain why neurogenesis has ceased in most parts of the adult CNS during the evolution of mammals, which show determinate growth.
Expression of TNF, IL1B, and iNOS2 in the neural cell after induced by Porphyromonas gingivalis with and without coating antibody anti-Porphyromonas gingivalis
Authors: Bachtiar Endang Winiati , Putri Citra F. , Soejoedono Retno D. , Bachtiar Boy M. 
Published: April 2021

Porphyromonas gingivalis has virulence factors such as gingipain and lipopolysaccharide, causing bacteremia to reach the brain and activate neuroinflammatory release cytokines. This study analyzed the effect of the co-culture of neuron cells with P. gingivalis coated with anti-P. gingivalis antibodies against cytokines produced by neuron cells. The gene expressions of the TNF, IL1B, iNOS2 in neurons was evaluated using RT-qPCR. The results showed that P. gingivalis coated with anti-P. gingivalis antibody before co-culture with neuron cells could decrease the gene expression of TNF, IL1B, and iNOS2 of neuron cells.
Three-Color FISH Method: Dose-Effect Curves for Translocations in Peripheral Blood Lymphocyte Cultures after Gamma-Irradiation In Vitro
Authors: Nugis V. , Snigiryova G , Lomonosova E. , Kozlova M. , Nikitina V. 
Published: April 2021

Purpose: Plotting dose-effect curves for translocations identified using the tricolor FISH method based on the results of cytogenetic analysis of cultures of peripheral blood lymphocytes of healthy donors after in vitro gamma irradiation.
Material and methods: Venous blood was obtained from three donors (2 men and 1 woman aged from 28 to 41 years) and subjected to in vitro gamma irradiation from a 60Co source at doses of 0.10; 0.15; 0.25; 0.35; 0.50; 0.75; 1.00; 1.50; 2.00 and 3.00 Gy at 37 ° C (dose rate 0.5 Gy / min). For tricolor FISH staining, two different sets of DNA probes were used for chromosome pairs 1, 4, 12 and 2, 3, 8. Metaphases with a quasi-diploid number of chromosomes (40-46) and a complete set of all FISH-stained chromosomes, taking into account their total length, were selected for analysis. Differentiation of stable and unstable cells was also carried out. In the cytogenetic analysis, traditional terminology was used with the designation of translocations as reciprocal (complete, two-sided), non-reciprocal (terminal, incomplete, or unilateral), or interstitial.
Results: The obtained numerical data were used to statistically compare the frequencies of FISH-recorded translocations when using different sets of DNA probes, when calculating of chromosome aberrations were in all (unstable and stable) and stable metaphase cells, when comparing of the frequencies of FISH-recorded translocations and dicentrics, and assessing of the contribution of the level of translocations between FISH-stained chromosome pairs in the total translocation frequency. The plotted dose-effect curves generally corresponded to the linear-quadratic form.
Conclusion: Dose dependences obtained for translocations using two different selected tricolor sets of DNA probes did not differ statistically significantly. At the same time, cytogenetic analysis of only stable metaphase cells revealed a tendency to register lower levels of translocations than when analyzing all cells (unstable and stable ), at the highest doses of 2 and 3 Gy. The levels of dicentrics formed with the participation of FISH-stained chromosomes were significantly lower than the number of observed translocations. The quantitative contribution of translocations between FISH-stained pairs of chromosomes turned out to be very low, which clearly does not contribute to an increase in the sensitivity of the FISH method of retrospective dose estimation as compared to its one-color version. At the same time, the three-color FISH-staining makes it possible to identify such variants of chromosomal rearrangements that are not recorded using the one-color FISH method.
Possibilities of Multislice Computed Tomography in the Diagnosis of Atheroclerotic Lesions of the Main Vessels for Type 2 Diabetes and Other Variants Disorders of Carbohydrate Metabolism
Authors: Praskurnichiy E , Ionova E , Begunova I , Knyazev A 
Published: April 2021

Purpose: Study of structural and morphological features of atherosclerotic lesions of large main vessels (carotid arteries) in
type 2 diabetes mellitus.
Material and methods: The study included 78 patients. Exclusion criteria: age under 40 years, pregnancy, acute infectious
diseases, as well as chronic diseases within less than 2 weeks from the onset of complete clinical and laboratory remission, severe
cardiac (LVEF < 30 %) and renal (blood creatinine > 300 mmol/l) insufficiency, alcohol abuse or drug dependence.
There were 44 men (56.4 %) and 34 women (43.6 %) in the group surveyed. Coronary heart disease was detected in 54 (69.2 %)
individuals, 24 (30.8 %) of the examined individuals had no signs of coronary heart disease; 19 (24.4 %) people had a history of stroke,
18 (23 %) people — myocardial infarction. 42 people (53.8 %) had dyscirculatory encephalopathy of various degrees, 34 (43.6 %) had
hypertension, 42 patients had carbohydrate metabolism disorders, 12 (15.3 %) patients had type 2 diabetes, and 30 (38.4 %) patients
had metabolic syndrome.
Three groups of subjects were formed. The group of people without metabolic syndrome included 48 people (61.5 % of the
total number of examined). The group of people with metabolic syndrome without type 2 diabetes included 18 individuals (23.1 %
of the total number of examined). The group of people with type 2 diabetes included 12 individuals (15.4 % of the total number of
examined).
The examination of patients included: physical examination; laboratory diagnostics; electrocardiography; transthoracic
echocardiography; multislice computed tomography with angiocontrast.
Results: 78 patients were found to have different density of atherosclerotic plaques. There were no differences in volume
among the groups of people surveyed. In patients with type 2 diabetes, there is a decrease in the lipid-fibrous component and an
increase in the density of atherosclerotic plaque.
Conclusion: Multislice computed tomography can detect various forms of vascular damage, the progression of the process, and
assess the severity of structural and morphological manifestations of atherosclerosis in type 2 diabetes and metabolic syndrome
at an early stage.
Calculation of Internal Dose and Possible Limits for Intakes of Radionuclides in Case of Plutonium Wounds
Authors: Molokanov A. , Kukhta B. , Galushkin B. 
Published: April 2021

Purpose: Assessment of the degree of compliance with the principles of radiation safety and regulatory requirements in case of plutonium wounds.
Material and methods: Using a wound intake of plutonium by a worker as an example, issues of the formation of the internal dose due to the wound intake and formal comparison of calculated dose values with regulatory requirements are considered. The calculations are carried out using expert analysis of the experimental data on the urine excretion of plutonium during the observation period of 7 years based on the ICRP model for direct intake into blood. In addition, calculations are carried out using prognostic assessment of the same dose values based on the biokinetic model for radionuclide-contaminated wounds published by NCRP Report No 156 together with the above model of the ICRP for plutonium compounds Strong, Colloids, Particles and Fragment.
Results: Based on the calculations, possible annual limits on intakes (ALI) of radionuclides in case of plutonium wounds are derived. As criteria for determining the ALI, dose values were taken that due to the uptake of the radionuclide into the systemic circulation from the wound for any calendar year considered for 50 years after the wound intake of selected plutonium compound. Namely, the committed effective dose; the effective dose implemented in a year and the organ annual equivalent dose (to bone surface and liver).
Conclusion: Based on the analysis of the above calculations, the authors formulated the formation features of the employee’s internal exposure due to wound intake of plutonium and recommendations for determining the value of plutonium intake in the wound, evaluating the effectiveness of decorporation therapy and determining the type of radionuclide compound. This allows one to more accurately assess the degree of compliance with regulatory requirements and make an informed decision on the necessary measures of medical intervention and their urgency.