Search results for "δ"
showing 10 items of 315 documents
IL-12 Expands and Differentiates Human Vγ2Vδ2 T Effector Cells Producing Antimicrobial Cytokines and Inhibiting Intracellular Mycobacterial Growth
2019
While IL-12 plays a key role in differentiation of protective CD4+ Th1 response, little is known about mechanisms whereby IL-12 differentiates other T-cell populations. Published studies suggest that predominant Vγ2Vδ2 T cells in humans/nonhuman primates (NHP) are a fast-acting T-cell subset, with capacities to rapidly expand and produce Th1 and cytotoxic cytokines in response to phosphoantigen (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP) produced by Mycobacterium tuberculosis (Mtb) or others. However, whether IL-12 signaling pathway mediates fast-acting and Th1 or anti-microbial features of Vγ2Vδ2 T cells remains poorly defined. Here, we show that IL-12, but not other IL-12 fami…
Tumor-Infiltrating γδ T Lymphocytes: Pathogenic Role, Clinical Significance, and Differential Programing in the Tumor Microenvironment.
2014
There is increasing clinical evidence indicating that the immune system may either promote or inhibit tumor progression. Several studies have demonstrated that tumors undergoing remission are largely infiltrated by T lymphocytes [tumor-infiltrating lymphocytes (TILs)], but on the other hand, several studies have shown that tumors may be infiltrated by TILs endowed with suppressive features, suggesting that TILs are rather associated with tumor progression and unfavorable prognosis. γδ T lymphocytes are an important component of TILs that may contribute to tumor immunosurveillance, as also suggested by promising reports from several small phase-I clinical trials. Typically, γδ T lymphocytes …
Methodologies to study soil nitrogen Méthodes pour l'étude de l'azote dans le sol Metodologie per lo studio dell'azoto nel suolo
2011
Nitrogen (N) is a key element within terrestrial ecosystems and, thus, the whole knowledge of its transformation processes is crucial. Especially in soil, complex and heterogeneous system, N undergoes several transformations as it is indicated by its various oxidation states. Moreover, it mainly occurs under a number of organic forms, whose identification and quantification is still challenging. Here, we review some extraction methodologies of N from soil, but also the isotope dilution technique, which helps in assessing gross N mineralisation. Finally, we discuss the NanoSIMS technique, which shows a good potential for investigating soil N dynamics at nanoscale. Résumé L'azote (N) est un é…
Kalcīts un tā veidošanās apstākļi Franas stāva smilšakmeņos un dolomītos Latvijā
2019
Maģistra darbā “Kalcīts un tā veidošanās apstākļi Franas stāva smilšakmeņos un dolomītos Latvijā” raksturotas kalcīta fizikālās īpašības, ķīmiskais sastāvs un veidošanās apstākļi. Pētījumi veikti 16 Amatas, Pļaviņu, Daugavas un Stipinu svītas atradnēs un atsegumos. Dokumentēti ģeoloģiskie griezumi, pētītas kalcīta fluorescences izpausmes un citas fizikālās īpašības, attiecības ar smilšakmens un dolomīta komponentiem plānslīpējumos, noteikts kalcīta ķīmiskais sastāvs un oglekļa stabilo izotopu attiecības. Secināts, ka kalcīts Amatas svītas smilšakmeņos un Pļaviņu, Daugavas un Stipinu svītas dolomītos kristalizējies līdzīgos apstākļos – no atmosfēras izcelsmes pazemes ūdeņiem sauszemes apstāk…
Kalcīts un tā veidošanās apstākļi augšējā devona Daugavas svītas dolomītos Latvijas centrālajā un austrumu daļā
2017
Bakalaura darbā “Kalcīts un tā veidošanās apstākļi augšējā devona Daugavas svītas dolomītos Latvijas centrālajā un austrumu daļā” ir raksturotas minerāla kalcīta fizikālās īpašības, mikroelementu saturs un veidošanās apstākļi. Pētījumi veikti 8 dolomīta atradnēs; ģeoloģiskajā griezumā un atradņu teritorijā salīdzinātas kalcīta īpašības. Testētas kalcīta fluorescences izpausmes, pētīti plānslīpējumi, raksturoti kalcītā sastopamie mikroelementi un oglekļa stabilo izotopu attiecības tajā. Secināts, ka kalcīts kristalizējies no atmosfēras ūdeņiem sauszemes apstākļos. Šis minerāls veidojies paleokarsta procesa beigu stadijā pēc iegruvumu izveidošanās. Atslēgas vārdi: mineraloģija, paleokarsts, f…
Oxygen Vacancy Formation and Migration within the Antiphase Boundaries in Lanthanum Scandate-Based Oxides: Computational Study.
2022
The study was performed with the financial support from the Latvian Council of Science under the grant agreement LZP-2020/2-0009. Calculations were performed at the HLRS, University of Stuttgart, within the project 12939 DEFTD. The Institute of Solid State Physics, University of Latvia (Latvia), as the Centre of Excellence has received funding from the European Union’s Horizon 2020 Frame-work Programme H2020-WIDESPREAD-01-2016-2017-Teaming Phase2 under grant agreement No. 739508, project CAMART2.
Modificētās L-ornitīna δ-aminotransferāzes strukturālie pētījumi jaunu diazonamīda A struktūranalogu dizainam
2015
Darba mērķi ir izstrādāt metodi rekombinantas modificētās ornitīna δ-aminotransferāzes (MOAT) produkcijai un kristalizēšanai, analizēt MOAT strukturālās atšķirības no ornitīna δ-aminotransferāzes (OAT), kā arī noteikt MOAT kristālu struktūru kompleksā ar Latvijas Organiskās sintēzes institūta pētnieku sintezētajiem diazonamīda A struktūranalogiem. Tādejādi, varētu noteikt MOAT un diazonamīda A struktūranalogu ķīmisko mijiedarbību veidu, iegūstot zināšanas jaunu MOAT inhibitoru dizainam. Bakalaura darba laikā tika iegūts rekombinants, E.coli producēts, MOAT, kā arī MOAT kristālstruktūra kompleksā ar piridoksāla 5´ fosfātu. Bakalaura darbs tika izstrādāts Latvijas Biomedicīnas pētījumu un stu…
Regulación del factor transcripcional Whi7 y la proteinquinasa C en el proceso de Start y el checkpoint de integridad del DNA
2019
Start es el principal punto de control del ciclo celular en el que las células se comprometen a una nueva ronda de división celular. Este punto de control implica la activación irreversible de un programa transcripcional por los complejos Cdc28-Cln a través de la inactivación del represor transcripcional de Start Whi5. En este trabajo se proporcionan nuevas claves sobre cómo Whi7, una proteína relacionada a nivel de secuencia con Whi5, reprime Start. Nuestros resultados demuestran que Whi7 es un parálogo genuino de Whi5. Ambas proteínas colaboran en la represión de Start, aunque presentan diferencias importantes en su regulación que convierten a Whi7 en el represor de Start por excelencia e…
Benthic foodweb structure in a large shallow lake studied by stable isotope analysis
2014
The benthic foodweb structure of Lake Võrtsjärv, a large (270 km2), shallow, and turbid Estonian lake, was evaluated based on C and N stable-isotope signatures (δ13C, δ15N). Variation in δ13C between sampling sites was not related to site proximity to the littoral zone or the more vegetated southern part of the lake, but rather appeared to be influenced by in-situ site peculiarities. δ13C was stable temporally and between functional feeding groups, a result implying that the whole benthic food web of the lake relies largely on the same C source admixture, essentially particulate organic matter (POM). Thus, the foodweb composition of Lake Võrtsjärv is remarkably homogeneous given the lake’s …
Metabolic Changes in Tumor Microenvironment: How Could They Affect γδ T Cells Functions?
2021
The metabolic changes that occur in tumor microenvironment (TME) can influence not only the biological activity of tumor cells, which become more aggressive and auto sustained, but also the immune response against tumor cells, either producing ineffective responses or polarizing the response toward protumor activity. γδ T cells are a subset of T cells characterized by a plasticity that confers them the ability to differentiate towards different cell subsets according to the microenvironment conditions. On this basis, we here review the more recent studies focused on altered tumor metabolism and γδ T cells, considering their already known antitumor role and the possibility of manipulating th…