337 research outputs found
Use of Glauconite in Potato Cultivation Technology
In intensive technologies of cultivation of potatoes, the need for trace elements is increasing. The concentration of trace elements in plants is very small, but the importance of these elements in biochemical processes is difficult to overestimate. The deficiency of trace elements is the root cause of many functional disorders. Trace elements in plants are part of enzymes, stimulate and accelerate plant development, increase resistance to adverse environmental conditions, etc. Also, with their shortage, crop productivity decreases. The use of natural minerals, such as glauconite, containing trace elements, allows improving comprehensive nutrition and increase productivity. Getting early production of high quality potatoes in the summer is important and relevant in the modern world. The use of glauconite in the conditions of the Moscow region, along with fertilizers and irrigation, allows obtaining high-quality products and increasing productivity by 6.3... 29.0%
Problems of digital transformation of laboratory practicum during teaching of natural science disciplines
The problems of increasing the share of digital learning resources in educational practice for the natural science disciplines, in particular chemistry, within the system of higher technical educational institutions have been analyzed. The elements that should include a laboratory practicum, which is delivered with the use of information and communication technologies, are considered. The necessity of combined use of virtual elements of the practicum with the implementation of real experimental laboratory work is reasoned. One of the possible forms of implementation of virtual laboratory work in chemistry is considered, the necessary components in the content, structure and form of interaction between the teacher and students when performing such work are noted. The problems of digital transformation of laboratory practice during teaching of general and inorganic chemistry are discussed
LABORATORY CHANGES OF ORAL FLUIDS AT EXACERBATION OF PARENCHYMATOUS PAROTITIS
In this work authors have studied the laboratory parameters of mixed saliva and the severity of the carious process of patients with parenchymal parotitis without complications and complicated by abscess formation in the parotid gland. More pronounced changes in the mixed saliva with severe caries process are observed at patients with an exacerbation of parenchymatous parotitis on the background of abscess formation. Adverse conditions associated with abscess formation, can be explained as a "vicious circle" in the form of violation of mineralizing and secretory functions of mixed saliva and poor oral hygiene, which is an additional source of infection
SECTIONAL DIAGNOSTICS OF THE CONNECTING TISSUE DYSPLASIA
The analysis of the morphological phenomena met during sectional observations of persons with a dysplasia of a connecting tissue is given. Authors underline inter-relations between the phenomena connected with a locomotorium and pathology of the skin and visceral organs. Recommendations concerning the analysis of morphological phenomena at dysplasia of the connecting tissue in the diagnostic aspect are given
Duplications of KIAA1549 and BRAF screening by Droplet Digital PCR from formalin-fixed paraffin-embedded DNA is an accurate alternative for KIAA1549-BRAF fusion detection in pilocytic astrocytomas
Pilocytic astrocytomas represent the most common glioma subtype in young patients and account for 5.4% of all gliomas. They are characterized by alterations in the RAS–MAP kinase pathway, the most frequent being a tandem duplication on chromosome 7q34 involving the BRAF gene, resulting in oncogenic BRAF fusion proteins. BRAF fusion involving the KIAA1549 gene is a hallmark of pilocytic astrocytoma, but it has also been recorded in rare cases of gangliogliomas, 1p/19q co-deleted oligodendroglial tumors, and it is also a common feature of disseminated oligodendroglial-like leptomeningeal neoplasm. In some difficult cases, evidence for KIAA1549-BRAF fusion is of utmost importance for the diagnosis. Moreover, because the KIAA1549-BRAF fusion constitutively activates the MAP kinase pathway, it represents a target for drugs such as MEK inhibitors, and therefore, the detection of this genetic abnormality is highly relevant in the context of clinical trials applying such new approaches. In the present study, we aimed to use the high sensitivity of Droplet Digital PCR (DDPCR™) to predict KIAA1549-BRAF fusion on very small amounts of formalin-fixed paraffin-embedded tissue in routine practice. Therefore, we analyzed a training cohort of 55 pilocytic astrocytomas in which the KIAA1549-BRAF fusion status was known by RNA sequencing used as our gold standard technique. Then, we analyzed a prospective cohort of 40 pilocytic astrocytomas, 27 neuroepithelial tumors remaining difficult to classify (pilocytic astrocytoma versus ganglioglioma or diffuse glioma), 15 dysembryoplastic neuroepithelial tumors, and 18 gangliogliomas. We could demonstrate the usefulness and high accuracy (100% sensitivity and specificity when compared to RNA sequencing) of DDPCR™ to assess the KIAA1549-BRAF fusion from very low amounts of DNA isolated from formalin-fixed paraffin-embedded specimens. BRAF duplication is both necessary and sufficient to predict this fusion in most cases and we propose that this single analysis could be used in routine practice to save time, money, and precious tissue
ATOMIC-FORCE MICROSCOPY AS THE ADDITIONAL METHOD OF EXAMINATION OF FIRM TISSUES
The purpose of the work: to study opportunities of application of atomic-force microscopy for morphological diagnostics of the pathology of the connecting tissue on firm tissues of teeth and bones.Materials and research methods: the analysis of the packing extent, size and form of bone plates, enamel prisms, size of an inter-prismatic interval and its height on 30 removed teeth and the bone tissue of persons with a connecting tissue dysplasia and 27 removed teeth and the bone tissue of a control group by the nuclear-power microscopy method.Results: research of a bone tissue and enamel of teeth is carried out in conditions of the connecting tissue pathology in comparison with patients without it. It was established that collagen configuration in conditions of the connecting tissue pathology assumes increase of an interval between fibers up to 98 nm which reduce the quantitative content of the mineral matrix in a bone. In enamel of teeth we have also determined violations of forms and sizes of enamel prisms (5.5х5.4 microns) with increasing distance between enamel prisms up to 1.6 micron.Conclusions: 1. Results of examination of the ultra-structure and mineral structure allow to talk about violation of mineralization and organization of enamel of teeth and the bone tissue of persons with the connecting tissue pathology symptoms. 2. Use of the nuclear-power microscopy allows to study native cellular cultures, including firm tissue of teeth and the bone tissue. 3. The specified facts can be used as a basis for the diagnostics of the connecting tissue pathology and for determination of individual characteristics in the process of identification of the personality
DNA copy number alterations in central primitive neuroectodermal tumors and tumors of the pineal region: an international individual patient data meta-analysis
Little is known about frequency, association with clinical characteristics, and prognostic impact of DNA copy number alterations (CNA) on survival in central primitive neuroectodermal tumors (CNS-PNET) and tumors of the pineal region. Searches of MEDLINE, Pubmed, and EMBASE—after the original description of comparative genomic hybridization in 1992 and July 2010—identified 15 case series of patients with CNS-PNET and tumors of the pineal region whose tumors were investigated for genome-wide CNA. One additional case study was identified from contact with experts. Individual patient data were extracted from publications or obtained from investigators, and CNAs were converted to a digitized format suitable for data mining and subgroup identification. Summary profiles for genomic imbalances were generated from case-specific data. Overall survival (OS) was estimated using the Kaplan-Meier method, and by univariable and multivariable Cox regression models. In their overall CNA profiles, low grade tumors of the pineal region clearly diverged from CNS-PNET and pineoblastoma. At a median follow-up of 89months, 7-year OS rates of CNS-PNET, pineoblastoma, and low grade tumors of the pineal region were 22.9±6, 0±0, and 87.5±12%, respectively. Multivariable analysis revealed that histology (CNS-PNET), age (≤2.5years), and possibly recurrent CNAs were associated with unfavorable OS. DNA copy number profiling suggests a close relationship between CNS-PNET and pineoblastoma. Low grade tumors of the pineal region differed from CNS-PNET and pineoblastoma. Due to their high biological and clinical variability, a coordinated prospective validation in future studies is necessary to establish robust risk factor
Overcoming multiple drug resistance mechanisms in medulloblastoma
Introduction: Medulloblastoma (MB) is the most common malignant paediatric brain tumour. Recurrence and progression of disease occurs in 15-20% of standard risk and 30-40% of high risk patients. We analysed whether circumvention of chemoresistance pathways (drug export, DNA repair and apoptotic inhibition) can restore chemotherapeutic efficacy in a panel of MB cell lines. Results: We demonstrate, by immunohistochemistry in patient tissue microarrays, that ABCB1 is expressed in 43% of tumours and is significantly associated with high-risk. We show that ABCB1, O6-methylguanine-DNA-methyltransferase (MGMT) and BCL2 family members are differentially expressed (by quantitative reverse transcription polymerase chain reaction, Western blotting and flow cytometry) in MB cell lines. Based on these findings, each pathway was then inhibited or circumvented and cell survival assessed using clonogenic assays. Inhibition of ABCB1 using vardenafil or verapamil resulted in a significant increase in sensitivity to etoposide in ABCB1-expressing MB cell lines. Sensitivity to temozolomide (TMZ) was MGMT-dependent, but two novel imidazotetrazine derivatives (N-3 sulfoxide and N-3 propargyl TMZ analogues) demonstrated ≥7 fold and ≥3 fold more potent cytotoxicity respectively compared to TMZ in MGMT-expressing MB cell lines. Activity of the BAD mimetic ABT-737 was BCL2A1 and ABCB1 dependent, whereas the pan-BCL2 inhibitor obatoclax was effective as a single cytotoxic agent irrespective of MCL1, BCL2, BCL2A1, or ABCB1 expression. Conclusions: ABCB1 is associated with high-risk MB; hence, inhibition of ABCB1 by vardenafil may represent a valid approach in these patients. Imidazotetrazine analogues of TMZ and the BH3 mimetic obatoclax are promising clinical candidates in drug resistant MB tumours expressing MGMT and BCL2 anti-apoptotic members respectively
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