microscopic analysis
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2022 ◽  
Vol 43 (2) ◽  
pp. 585-598
Author(s):  
Ana Paula Molinari Candeias ◽  
◽  
Gabrieli Maria Huff ◽  
Adriana Fiorini Rosado ◽  
André Luis Vriesman Beninca ◽  
...  

The objective of this study is to compare the direct fecal smear (DFS) and centrifugal sedimentation (CS) methods in the detection of Cryptosporidium spp. oocysts in fecal samples of dairy calves. One hundred and fourteen fecal samples were collected from calves aged up to six months from 10 dairy farms located in Palotina and Francisco Alves, Paraná, Brazil. The microscopic analysis revealed the presence of Cryptosporidium spp. oocysts in 51.75% (59/114) of the samples in both methods. In CS, 48.25% (55/114) of the samples were positive, while in DFS slides, only 6.14% (7/114) were positive. Only 4 samples were positive exclusively in DFS. To ensure that there were no false-negative results in the microscopic analysis, the 55 samples that were negative in both DFS and CS were selected for molecular analysis using the nested PCR (nPCR). Of these 55 samples, 24% (13/55) were positive and forwarded for sequencing part of the genome, which made it possible to identify C. parvum, C. bovis and C. ryanae. Besides the characterization of the Cryptosporidium species, it was possible to identify bacteria of the genus Acinetobacter interfering directly in the analyzed samples. The microscopic analysis also revealed higher sensitivity when CS was used to make the fecal smears. However, some samples that were negative in this technique had positive PCR results. Thus, molecular analysis is indicated to confirm cases of Cryptosporidium spp. Further studies are necessary to prove the specificities of the used primers since the results obtained in nPCR were positive for the protozoan but, when genetic sequencing was performed, Acinetobacter spp. was identified.


2022 ◽  
Author(s):  
Xinrui Wang ◽  
Zhihong Yin ◽  
Lingli Chen ◽  
Liushuai Hua ◽  
Fei Ren ◽  
...  

Abstract Bisphenol A (BPA) is one of the typical environmental endocrine disruptors. BPA was leached from polycarbonate containers into food and water, and it has been detected in collective samples from humans. Microtubule-associated protein 2 (MAP2) and Tau maintain microtubule normal function and promote the normal development of the nervous system. Synaptophysin (SYP) and drebrin (Dbn) proteins are involved in regulating synaptic plasticity. This study aimed to determine the adverse effects of BPA on Neuro-2a cells by investigating the synaptic and cytoskeletal damage. Cells were exposed to 0 (Minimum Essential Medium, MEM), 0.01% (v/v) DMSO and 150 µM BPA for 12, 24, or 36 h. Morphological analysis revealed that the cells in the BPA-treated groups shrank, collapsed, and had a reduced number of synapses compared with those in the control groups. CCK-8 and LDH assays showed that the mortality of Neuro-2a cells increased as the BPA treatment time was prolonged. Transmission electron microscopic analysis further revealed that cells demonstrated nucleolar swelling and nuclear membrane and partial mitochondrial dissolution or condensation following BPA exposure. BPA also significantly decreased the relative protein expression levels of MAP2, Tau, and Dbn (P < 0.01). Interestingly, the relative protein expression levels of SYP increased (P < 0.01). These results indicated that BPA damaged the development and proliferation of Neuro-2a cells by disrupting cytoskeleton and synaptic integrity.


2022 ◽  
pp. 38-44
Author(s):  
М.С. Жанибек ◽  
К.К. Орынбасарова

В данной статье представлены результаты микроскопического исследования особенностей анатомического строения (листья, цветки) растения пижмы сантолинной (Tanacetum Santolina). Цель работы: изучение анатомического строения надземных органов, определение подлинности и отличия от других видов. Материалы и методы: объект исследования - цветки пижмы сантолинной, собранные в период цветения в мае 2020 года в предгорных равнинах Каратау. Микроскопическое исследование цветков пижмы сантолинной проводилось в соответствии с требованиями государственной фармакопеи Республики Казахстан. С помощью микроскопа Биолам-5 изучался объект с увеличением от х40 до х400. Исследование срезов и создание микрорисунков проводили с помощью цифрового камерного тринокулярного микроскопа «МТ300L» (Япония) (увеличенный 7х1,5х4,5; 7х1,5х8; 7х1,5х40). Результаты и обсуждения: изучены диагностические признаки для определения цельного сырья: диагностические признаки листьев, форма клеток эпидермиса, тип аппарата устьиц, строение волосков и эфирномасличных желез; формы оксалата кальция. Выводы: проведен микроскопический анализ цветков пижмы сантолинной. Для определения подлинности этого сырья были выявлены анатомодиагностические признаки. Во всех частях растения встречаются одноклеточные волоски и пучковые волокна. На обеих частях листовой пластины хорошо видны волокна и волоски, устьица, пигментные полости. Кристаллы оксалата кальция, находятся в мезофильных полостях листа. В цветках оксалат кальция встречается только в виде четырехугольного кристалла. На анатомическом признаке измельченного сырья видны эфирномасличные железки. Форма эфирно-масличных желез обнаруживает основные диагностические признаки цветков и листьев пижмы сантолинной. Анатомические характеристики позволяют повысить уровень стандартизации, дальнейшее изучение лекарственного растительного сырья This article presents the results of a microscopic study of the anatomical structure (leaves, flowers) of the Santolina’s tansy plant (Tanacetum Santolina). The purpose of the work: to study the anatomical structure of aerial organs, to determine authenticity and differences from other species. Materials and methods: the object of research is the flowers of Santolina’s tansy collected during the flowering period in May 2020 in the foothill plains of Karatau. Microscopic examination of the flowers of Santolina’s tansy was carried out in accordance with the requirements of the State Pharmacopoeia of the Republic of Kazakhstan. Using a Biolam-5 microscope with magnification from x40 to x400 an object was studied. The study of sections and the creation of micro-nozzles was carried out using a digital chamber trinocular microscope "MT300L" (Japan) (enlarged 7x1.5x4.5; 7x1.5x8; 7x1.5x40). Results and discussions: diagnostic signs for the determination of whole raw materials were studied: diagnostic signs of leaves, the shape of epidermis cells, the type of stomatal apparatus, the structure of hairs and essential oil glands; forms of calcium oxalate. Conclusions: microscopic analysis of flowers of Santolina’s tansy was carried out. Anatomical and diagnostic signs were identified to determine the authenticity of this raw material. Unicellular hairs and beam fibers are found in all parts of the plant. Fibers and hairs, stomata, pigment cavities are clearly visible on both parts of the leaf plate. Calcium oxalate crystals are located in the mesophilic cavities of the leaf. In flowers, calcium oxalate occurs only in the form of a quadrangular crystal. On the anatomical feature of the crushed raw materials, essential oil glands are visible. The shape of the essential oil glands reveals the main diagnostic signs of flowers and leaves of santolina tansy. Anatomical characteristics make it possible to increase the level of standardization, further study of medicinal plant raw materials.


Haematologica ◽  
2022 ◽  
Author(s):  
Joanne Lacey ◽  
Simon J. Webster ◽  
Paul R. Heath ◽  
Chris J. Hill ◽  
Lucinda Nicholson-Goult ◽  
...  

Germline defects affecting the DNA-binding domain of the transcription factor FLI1 are associated with a bleeding disorder that is characterised by the presence of large, fused α-granules in platelets. We investigated whether the genes showing abnormal expression in FLI1-deficient platelets could be involved in platelet α-granule biogenesis by undertaking transcriptome analysis of control platelets and platelets harbouring a DNA-binding variant of FLI1. Our analysis identified 2276 transcripts that were differentially expressed in FLI1- deficient platelets. Functional annotation clustering of the coding transcripts revealed significant enrichment for gene annotations relating to protein transport, and identified Sorting nexin 24 (SNX24) as a candidate for further investigation. Using an iPSC-derived megakaryocyte model, SNX24 expression was found to be increased during the early stages of megakaryocyte differentiation and downregulated during proplatelet formation, indicating tight regulatory control during megakaryopoiesis. CRISPR-Cas9 mediated knockout (KO) of SNX24 led to decreased expression of immature megakaryocyte markers, CD41 and CD61, and increased expression of the mature megakaryocyte marker CD42b (p=0.0001), without affecting megakaryocyte polyploidisation, or proplatelet formation. Electron microscopic analysis revealed an increase in empty membrane-bound organelles in SNX24 KO megakaryocytes, a reduction in α-granules and an absence of immature and mature multivesicular bodies, consistent with a defect in the intermediate stage of α-granule maturation. Co-localisation studies showed that SNX24 associates with each compartment of α-granule maturation. Reduced expression of CD62P and VWF was observed in SNX24 KO megakaryocytes. We conclude that SNX24 is required for α-granule biogenesis and intracellular trafficking of α-granule cargo within megakaryocytes.


2022 ◽  
Vol 906 ◽  
pp. 31-37
Author(s):  
Smbat V. Mazmanyan ◽  
Gayane Papyan ◽  
Tamara Sargsyan ◽  
Armine Baghdagyulyan ◽  
Tatevik Paytyan ◽  
...  

The paper presents the study of morphological characteristics of cement particles and reveals the influence of the structure of the cement grain composition on the physical and mechanical properties of cement. The following portland cements produced by “Hrazdan Cement Corporation” LLC, which have 52,5 MPa and 42,5 MPa compressive strength limit and hydraulic additives up to 20% and over 20% have been used for the experiment: CEM II/ A-P 42,5N, CEM II/ B-P 42,5N, CEM II/A-Q 42,5N, CEM II/B-Q, CEM II/A-L 42,5N, CEM II/B-L 42,5N, CEM II/A-M 42,5N, CEM II/B-M, CEM III/A-S 42,5N and CEM III/B-S 42,5N. Grain distribution in all the samples has been studied using a CILAS laser analyzer. Microscopic analysis of all the fractions has been carried out with the help of James Swift optical microscope. The given grain compositions have undergone chemical analysis in compliance with the requirements of interstate ISO 5382-2019 and ASTM C114-18 standards. Experimental studies and analyses show that the cements with microsilica have the highest value of water-cement ratio-W/C = 0.7, the highest by volume compression are the cements with volcanic slag-4 mm, the beginning of the bonding period is the longest in case of limestone cements - t = 140 minutes, followed by microsilica cements, and in third place there are artificial slag cements, the results of which are as follows: 130; 124 minutes. The summarized data show that microsilica cements have the highest compressive strength limit among the cements having the same percentage of additives-48.87 MPa.


Biomedicines ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 138
Author(s):  
Andreas Hammer ◽  
Geraldine Cerretti ◽  
Dario A. Ricciardi ◽  
David Schiffmann ◽  
Simon Maranda ◽  
...  

Calcium (Ca2+) elevation is an essential secondary messenger in many cellular processes, including disease progression and adaptation to external stimuli, e.g., gravitational load. Therefore, mapping and quantifying Ca2+ signaling with a high spatiotemporal resolution is a key challenge. However, particularly on microgravity platforms, experiment time is limited, allowing only a small number of replicates. Furthermore, experiment hardware is exposed to changes in gravity levels, causing experimental artifacts unless appropriately controlled. We introduce a new experimental setup based on the fluorescent Ca2+ reporter CaMPARI2, onboard LED arrays, and subsequent microscopic analysis on the ground. This setup allows for higher throughput and accuracy due to its retrograde nature. The excellent performance of CaMPARI2 was demonstrated with human chondrocytes during the 75th ESA parabolic flight campaign. CaMPARI2 revealed a strong Ca2+ response triggered by histamine but was not affected by the alternating gravitational load of a parabolic flight.


2022 ◽  
Vol 23 (2) ◽  
pp. 607
Author(s):  
Agnieszka Krakowiak ◽  
Liliana Czernek ◽  
Marta Pichlak ◽  
Renata Kaczmarek

In this study, we present a new selenium derivative, 2′-deoxyguanosine-5′-O-selenophosphate (dGMPSe), synthesized by the oxathiaphospholane method and adapted here for the synthesis of nucleoside selenophosphates. Using biochemical assays (HPLC- and fluorescence-based), we investigated the enzymatic activity of HINT1 towards dGMPSe in comparison with the corresponding thiophosphate nucleoside, i.e., dGMPS. Both substrates showed similar kcat and a small difference in Km, and during the reactions the release of reducing agents such as H2Se and H2S were expected and detected. MTT viability assay and microscopic analysis showed that dGMPSe was toxic to HeLa cancer cells, and this cytotoxicity was due to the release of H2Se. The release of H2Se or H2S in the living cells after administration of dGMPSe and/or dGMPS, both without carrier and by electroporation, was observed using a fluorescence assay, as previously for NMPS. In conclusion, our comparative experiments with dGMPSe and dGMPS indicate that the HINT1 enzyme is capable of converting (d)NMPSe to (d)NMP and H2Se, both in vitro and intracellularly. Since the anticancer activity of various selenium compounds depends on the formation of hydrogen selenide, the actual inducer of cell death, we propose that selenium-containing nucleotides represent another option as novel compounds with anticancer therapeutic potential.


2022 ◽  
Vol 9 ◽  
Author(s):  
Jia He ◽  
Xunyu Mao ◽  
Yundong Zhou ◽  
Qiang Tang

Calcium carbonate precipitation and crystallization induced by urease enzyme to solidify soil is known as biocement technology. The uses of waste and cheap materials can make this technology more cost-effective and practical for applications. In this study, calcium ions were obtained by dissolving waste concretes in acidic liquid. Sand columns were treated by enzyme-induced carbonate precipitation (EICP) with either concrete-extracted calcium or reagent calcium for comparison. Compressive strengths, calcium carbonate contents, and microscopic analysis on the treated sand were carried out. It was found that the compressive strength of the former could reach 833 kPa in the dry state and 204 kPa in the wet state after 5 times of EICP treatment, both of which were higher than that of the latter. The calcium carbonate contents could reach 2–3% after 3–5 times of treatment. Based on the scanning electron microscope (SEM) and X-ray diffractometer (XRD) analyses, the crystal type of calcium carbonate produced in sand was calcite. The comparative results showed that the treatment effect using concrete-extracted calcium was similar or better than that using reagent calcium.


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