The role of extracellular polysaccharide in cell viability and nitrogenase activity of Beijerinckia derxii

1992 ◽  
Vol 38 (9) ◽  
pp. 986-988 ◽  
Author(s):  
H. R. Barbosa ◽  
F. Alterthum

Cells of Beijerinckia derxii grown on NH4+ or N2 as the nitrogen source were treated to remove their extracellular polysaccharide layer without loss of viability. An adequate method for extracellular polysaccharide extraction was established. After extracellular polysaccharide removal N2-grown cells showed reduced nitrogenase activity, and when stirred for 90 min at 200 rpm, suffered a total loss of viability. In contrast, NH4+-grown cells were not affected when submitted to the same conditions. However, these cells showed a high sensitivity to saline solution. Key words: extracellular polysaccharide, nitrogenase, Beijerinckia derxii, exopolysaccharide.

1986 ◽  
Vol 39 (8) ◽  
pp. 1205 ◽  
Author(s):  
S Stojkovski ◽  
RJ Magee ◽  
J Liesegang

The uptake of molybdenum by certain bacteria hinders its role as a trace metal in the micronutrients for plant growth. The binding of molybdenum by the Gram-negative bacterium Pseudomonas aeruginosa, PAO1, has been investigated. A molybdenum complex of uronic acid, which forms in the extracellular polysaccharide layer (slime), was isolated and characterized by a variety of techniques. Comparisons with 'mimic' compounds of uronic acids suggest that Pseudomonas aeruginosa, PAO1, produces a binuclear, di-oxo-bridged magnesium salt MgMo2O4(C6H8O7)2.5H2O; this indicates the important role of uronic acids in metallic uptake by bacteria.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4230-4230
Author(s):  
Kodetthoor B. Udupa ◽  
Chhanda Bose

Abstract Erythropoietin (EPO) regulates the proliferation and differentiation of erythroid progenitors via its receptor, EPO-R and through various Mitogen activated protein kinase (MAPK) pathways. The role of EPO on other cell types is still unkown. In the present study we have elected to examine this aspect in a transformed pancreatic cell line, AR42J cells. We investigated the activation of two MAPKs, namely extracellular regulated kinase (ERK) and c-jun NH2-terminal kinase (JNK) after exposure of AR42J cells to 1 U/ml EPO using the Western blot analysis. We also examined cell viability during EPO exposure by high sensitivity fluoremetric method using CCK8. We found a rapid activation of ERK-1/2 in AR42J cells reaching the maximum of 3.3 fold in 5 min, while it took 30 min for JNK-1/2 to reach the maximum. In the absence of EPO, addition of specific JNK inhibitor, SP600125, reduced cell viability to 50% at a dose of 20 μM while with ERK inhibitor, UO126, cell viability was not reduced even up to 60 μM of the drug. To examine the effect of induction of MAPK by EPO on AR42J cell survival, cells were treated with inhibitors to ERK or JNK 1h prior to EPO addition and the cumulative cell survival were calculated from day 1 through 4. EPO addition to AR42J cells resulted in significantly higher cumulative cell survival of 1.00 ± 0.04 unit absorption compared to the value of 0.35 ± 0.02 unit absorption seen in controls without EPO. When cells were treated with EPO and ERK inhibitor a significantly higher cumulative cell survival of 1.50 ± 0.04 unit absorption was observed (p < 0.01) indicating ERK to be less effective in their survival. On the other hand, samples treated with EPO and JNK inhibitor had significantly lower cell survival (0.55 ± 0.06 unit absorption, p < 0.01) than the EPO control indicating an essential role of JNK in their survival. These results indicate that in EPO mediated survival of AR42J cells, activation of JNK appears to be more important than ERK activation thus indicating a key role of JNK in cell viability. It is very important to understand the role of EPO signaling in the viability of transformed cells since EPO is often supplemented after bone marrow transplantation to enhance the recovery after chemotherapy.


Author(s):  
Svitlana Gruschko

The article investigates the role of communicative-functional approach in the translation of scientific and technical literature, when the translation itself is seen as a tool to accomplish purposeful activity of communicators, representatives of different interlingual groups. In practical terms, the difficulties of translating scientific and technical texts are due to the peculiarities of scientific style, insufficient understanding of the terminology of a particular field of knowledge, which complicates the choice of adequate translation solutions. In this context, an important role is played by the translation strategy, where the communicativefunctional approach dominates. The translation is implicitly included in the communication structure between the author and the recipient. The relevance of the article is determined by the necessity of studying the problems of scientific and technical literature translation, taking into account the current realities of interlanguage information exchange. Key words: communicative-functional approach, interlingual communication, translation, structure


Author(s):  
Баяманова М.С.

Summary: The article deals with the analysis of the interpretational field of the basic lexical units which represent the meaning of the concept “woman” in English and Kyrgyz languages and cultures. Comparative – contrastive analytical data of the most frequently used in both languages variants of the interpretation of the concept “woman” have been given. The semantic fields of nuclear and nearnuclear meanings of the lexical units, transforming the notion of “woman” in English and Kyrgyz languages and also the place and role of these notions in cultures and philosophy of the nations on the basis of mentality and traditional values have been studied and described. The situations of the use of this or that variant of the meaning of lexical unit. A comparative study of the definitions of the word “woman’ in English and Kyrgyz languages have been given. Key words: concept, woman, interpretational field, notion, definition, semantic field, culture, language, linguoculture, transformation Аннотация: В статье рассматриваются интерпретационные поля основных лексических единиц, репрезентирующих значение концепта «женщина» в английской и кыргызской лингвокультурах. Приводятся сравнительно-сопоставительные аналитические данные наиболее употребительных в речи обоих языков вариантов интерпретации концепта «женщина». Изучены и описаны семантические поля ядерных и околоядерных значений лексических единиц, трансформирующих понятие «женщина» в английском и кыргызском языке, а также роль и место этих понятий в культурах и философии народов на основе менталитета и традиционных ценностей. Приводятся ситуации использования того или ино- го варианта значения лексической единицы, проведено сравнительное изучение определений слова «женщина» в английском и кыргызском языках. Ключевые слова: концепт, женщина, интерпретационное поле, понятие, определение, семантическое поле, культура, язык, лингвокультура, трансформация Аннотация: Макалада англис жана кыргыз тилдеринде жана маданияттарында «аял» концептинин маанисин репрезентациалаган негизги лексикалык бирдиктер каралат. «Аял» концептин эки тилдеги кѳп колдонулуучу интерпретациялоо варианттарынын аналитикалык салыштырма маалыматтары изил- делип берилген. Англис жана кыргыз тилдеринде «аял» түшүнүгүн трансформациялаган лексикалык бирдиктердин түп нуска жана ага жакындашкан маанилери иликтелип каралган. Берилген түшүнүктѳрдүн элдик философиясында жана маданиятында, менталитеттин жана салттын негизинде эл арасына кеӊири тараган, элдик тилде жана маданиятта ойногон ролу менен орду чагылдырылган. Ар түрдү ситацияларда колдонулуучу тиги же бул лексикалык бирдиктердин маанисинин варианттары каралган, «аял» деген сѳздун англис жана кыргыз тилдериндеги түшүндүрмѳлѳрү салыштырылып изилделген. Түйүндүү сѳздѳр: концепт, аял, интерпретациялоо мейкиндиги, түшүнүк, түшүндүрмѳ, семантикалык чѳйрѳ, маданият, тил, лингвомаданият, трансформациялоо


2020 ◽  
Vol 23 (16) ◽  
Author(s):  
Nashwan S. Albabawaty ◽  
Ali Y. Majid ◽  
Mohammed H. Alosami ◽  
Halla G. Mahmood

2019 ◽  
Vol 15 (3) ◽  
pp. 198-206 ◽  
Author(s):  
Sarfaraz Ahmed Mahesar ◽  
Saeed Ahmed Lakho ◽  
Syed Tufail Hussain Sherazi ◽  
Hamid Ali Kazi ◽  
Kamran Ahmed Abro ◽  
...  

Background: Captopril is the synthetic dipeptide used as an angiotensin converting enzyme inhibitor. Captopril is used to treat hypertension as well as for the treatment of moderate heart failure. Analytical instrumentation and methodology plays an important role in pharmaceutical analysis. Methods: This review presents some important applications of electrochemical modes used for the analysis of captopril. So far captopril has been analyzed by using different bare and modified working electrodes with a variety of modifiers from organic and inorganic materials to various types of nano particles/materials. Results: This paper presents some of the methods which have been published in the last few years i.e. from 2003 to 2016. This review highlights the role of the analytical instrumentation, particularly electrochemical methods in assessing captopril using various working electrodes. Conclusion: A large number of studies on voltammetry noted by means of various bare and modified electrodes. Among all of the published voltammetric methods, DPV, SWV, CV and miscellaneous modes were trendy techniques used to analyze captopril in pharmaceutical formulations as well as biological samples. Electrodes modified with nanomaterials are promising sensing tools as this showed high sensitivity, good accuracy with precision as well as selectivity. In comparison to chromatographic methods, the main advantages of electrochemical methods are its cheaper instrumentation, lower detection limit and minimal or no sample preparation.


Author(s):  
Upasana Ray ◽  
Debarshi Roy ◽  
Ling Jin ◽  
Prabhu Thirusangu ◽  
Julie Staub ◽  
...  

Abstract Background Aberrant lipogenicity and deregulated autophagy are common in most advanced human cancer and therapeutic strategies to exploit these pathways are currently under consideration. Group III Phospholipase A2 (sPLA2-III/PLA2G3), an atypical secretory PLA2, is recognized as a regulator of lipid metabolism associated with oncogenesis. Though recent studies reveal that high PLA2G3 expression significantly correlates with poor prognosis in several cancers, however, role of PLA2G3 in ovarian cancer (OC) pathogenesis is still undetermined. Methods CRISPR-Cas9 and shRNA mediated knockout and knockdown of PLA2G3 in OC cells were used to evaluate lipid droplet (LD) biogenesis by confocal and Transmission electron microscopy analysis, and the cell viability and sensitization of the cells to platinum-mediated cytotoxicity by MTT assay. Regulation of primary ciliation by PLA2G3 downregulation both genetically and by metabolic inhibitor PFK-158 induced autophagy was assessed by immunofluorescence-based confocal analysis and immunoblot. Transient transfection with GFP-RFP-LC3B and confocal analysis was used to assess the autophagic flux in OC cells. PLA2G3 knockout OVCAR5 xenograft in combination with carboplatin on tumor growth and metastasis was assessed in vivo. Efficacy of PFK158 alone and with platinum drugs was determined in patient-derived primary ascites cultures expressing PLA2G3 by MTT assay and immunoblot analysis. Results Downregulation of PLA2G3 in OVCAR8 and 5 cells inhibited LD biogenesis, decreased growth and sensitized cells to platinum drug mediated cytotoxicity in vitro and in in vivo OVCAR5 xenograft. PLA2G3 knockdown in HeyA8MDR-resistant cells showed sensitivity to carboplatin treatment. We found that both PFK158 inhibitor-mediated and genetic downregulation of PLA2G3 resulted in increased number of percent ciliated cells and inhibited cancer progression. Mechanistically, we found that PFK158-induced autophagy targeted PLA2G3 to restore primary cilia in OC cells. Of clinical relevance, PFK158 also induces percent ciliated cells in human-derived primary ascites cells and reduces cell viability with sensitization to chemotherapy. Conclusions Taken together, our study for the first time emphasizes the role of PLA2G3 in regulating the OC metastasis. This study further suggests the therapeutic potential of targeting phospholipases and/or restoration of PC for future OC treatment and the critical role of PLA2G3 in regulating ciliary function by coordinating interface between lipogenesis and metastasis.


Author(s):  
K. H. Sedeek ◽  
K. Aboualfotouh ◽  
S. M. Hassanein ◽  
N. M. Osman ◽  
M. H. Shalaby

Abstract Background Acute bilateral lower limb weakness is a common problem in children which necessitates a rapid method for diagnosis. MRI is a non-invasive imaging technique that produces high-quality images of the internal structure of the brain and spinal cord. Results MRI was very helpful in reaching rapid and prompt diagnosis in children with acute inability to walk. Acute disseminated encephalomyelitis (ADEM), Guillain–Barré syndrome (GBS), and acute transverse myelitis (ATM) were the most common causes in our study. MRI proved to be of high sensitivity in detecting the lesions and reaching the diagnosis in ADEM and GBS; however, there was no significant relation between the lesions’ size, enhancement pattern, and severity of the disease or prognosis, yet in ATM the site of the lesion and number of cord segment affection were significantly related to the severity of the disease and prognosis. Conclusion MRI is a quick tool to reach the diagnosis of children with acute secondary inability to walk, and to eliminate other differential diagnosis which is essential for proper treatment and rapid full recovery. It is highly sensitive in detecting the lesions, their site and size.


2021 ◽  
pp. 201010582110061
Author(s):  
Raja Ezman Raja Shariff ◽  
Hafisyatul Aiza Zainal Abidin ◽  
Sazzli Kasim

Cardiac amyloidosis is a severely underdiagnosed cause of heart failure with preserved ejection fraction. We report a case of highly probable transthyretin (ATTR) cardiac amyloidosis (ATTR-CA) diagnosed through the assistance of non-invasive multimodality imaging. An 81-year-old man presented with worsening dyspnoea, reduced effort tolerance and limb swelling. Examination and bedside investigations demonstrated congestive cardiac failure. On arrival, N-terminal-pro B-type natriuretic peptide was 2400 ng/L, and high-sensitivity troponin T was 78 mmol/L. Echocardiography showed severe left and right ventricular hypertrophy, and a Doppler study revealed diastolic dysfunction. Cardiac magnetic resonance imaging revealed on non-conventional dark blood sequence an abnormal inversion time for nulling myocardium suggestive of infiltrative disease, including amyloidosis. The patient was referred for nuclear-based studies involving technetium-99m pyrophosphate which demonstrated changes highly diagnostic of ATTR-CA. Early diagnosis of ATTR-CA remains paramount due to the increasing availability of disease-modifying therapies. Current guidelines recognise the role of multimodality imaging in confidently recognising the disease without the need for histological evidence in the appropriate context, providing an alternative means of diagnosis.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Xu Zhou ◽  
Jingliang He ◽  
Jinbo Chen ◽  
Yu Cui ◽  
Zhenyu Ou ◽  
...  

Abstract Background Leydig cells reflect the activation of inflammation, decrease of androgen production, inhibition of cell growth and promotion of cell apoptosis under orchitis. Maternally expressed gene 3 (MEG3) exerts a crucial role in various human diseases, but under orchitis, the role and underlying molecular mechanism of MEG3 in Leydig cells remain unclear. Methods Lipofectamine 2000 was used for the cell transfections. qPCR and western blots assay were applied to assess the gene expression. ELISA assay was used to measure the TNFα, IL6 and testosterone secretion. CCK8 and EdU assay was employ to test the cell viability and proliferation respectively. Luciferase reporter and RIP assay were introduced to detect the binding of miR-93-5p with MEG3 and PTEN. Results Lipopolysaccharides (LPS) induced TNFα and IL6 secretion, lowered testosterone production, inhibited cell viability and proliferation, and induced cell apoptosis in Leydig cells. MEG3 was upregulated in Leydig cells treated with LPS and that knockdown of MEG3 inhibited the role of LPS in Leydig cells. MEG3 absorbed miR-93-5p and that suppression of miR-93-5p restored the role of silenced MEG3 in Leydig cells under LPS treatment. miR-93-5p inhibited PTEN expression and that over-expressed PTEN alleviated the effect of miR-93-5p in Leydig cells treated with LPS. LPS activated the MEG3/miR-93-5p/PTEN signalling pathway in Leydig cells. Conclusions This study revealed that MEG3 serves as a molecular sponge to absorb miR-93-5p, thus leading to elevation of PTEN expression in Leydig cells under LPS treatment, offering a theoretical basis on which to establish potential new treatment strategies for orchitis.


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