Search results for "Vertebra"

Sabella spallanzanii mucus bacterial agglutinating activity after arsenic exposure. The equilibrium between predation safety and immune response stab…

2022

We report the Sabella spallanzanii mucus bacterial agglutination response after inorganic arsenic (As) exposure. As is actively adsorbed from the surrounding environment and accumulated at high concentrations in tissues as an anti-predatory strategy. Here we investigated the effect of high As concentrations on its immunobiological response. It may act on mucus lectins and on its ability to agglutinate bacteria. We concluded that As at high concentrations leads to the inhibition of pathogen recognition. Nevertheless, although its biological activity is significant reduced in winter, responses to As concentrations are very similar, and below a certain threshold do not induce alterations, supp…

Mugurkaulnieku salīdzināmā anatomija: īsa mācību grāmata augstākām mācību iestādēm un pašizglītībai

1938

Molecular evolution: Evidence for the monophyletic origin of multicellular animals

1995

Ecology and Diversity of Urban Pine Forest Soil Invertebrates in Rīga, Latvia / Augsnes Bezmugurkaulnieku Bioloģiskā Daudzveidība Urbānajos Priežu Me…

2015

Abstract A study on ecology and diversity of soil invertebrates of urban pine and mixed pine forests was carried out in seven different sampling plots in Rīga during 2014. Ninety eight soil samples were processed and in total, 40 426 specimens were extracted (of them, 25 237 specimens were identified to species level and 15 189 to order level). Indices (abundance, community similarity etc.) characterising faunal diversity and species communities of Rīga city soil fauna were estimated. The most numerous soil invertebrate groups were Collembola, Oribatida and Mesostigmata, accounting for 95% of all collected animals. There was rather high diversity of soil invertebrates in the disturbed urban…

ADDISC lumbar disc prosthesis: Analytical and FEA testing of novel implants

2023

The intact intervertebral disc is a six-freedom degree elastic deformation structure with shock absorption. 'Ball-and-socket' TDR do not reproduce these properties inducing zygapophyseal joint overload. Elastomeric TDRs reproduce better normal disc kinematics, but repeated core deformation causes its degeneration. We aimed to create a new TDR (ADDISC) reproducing healthy disc features. We designed TDR, analyzed (Finite Element Analysis), and measured every 500,000 cycles for 10 million cycles of the flexion-extension, lateral bending, and axial rotation cyclic compression bench-testing. In the inlay case, we weighted it and measured its deformation. ADDISC has two semi-spherical articular s…

Vertebrate Hedgehog is secreted on two types of extracellular vesicles with different signaling properties

2014

Hedgehog (Hh) is a secreted morphogen that elicits differentiation and patterning in developing tissues. Multiple proposed mechanisms to regulate Hh dispersion includes lipoprotein particles and exosomes. Here we report that vertebrate Sonic Hedgehog (Shh) is secreted on two types of extracellular-vesicles/exosomes, from human cell lines and primary chick notochord cells. Although largely overlapping in size as estimated from electron micrographs, the two exosomal fractions exhibited distinct protein and RNA composition. We have probed the functional properties of these vesicles using cell-based assays of Hh-elicited gene expression. Our results suggest that while both Shh-containing exo-ve…

Preliminary Studies on Microbial Biomass and the Microarthropod Community as Soil Health and Quality Indicators in Urban Grasslands, Rīga as an Examp…

2015

Antropogēnais piesārņojums tiek uzskatīts par vienu no galvenajiem faktoriem, kas ietekmē augsni pilsētās. 2014. gadā uzsākts pētījums par augsnes kvalitāti urbānajos zālājos Rīgā. Pētījuma mērķis bija noteikt augsnes mikrobiālo biomasu un augsnes sīkposmkāju kopienu dažādu zālāju augsnēs Rīgā un izvērtēt iespējas tos izmantot kā pilsētvides augsnes veselības un kvalitātes rādītājus. Rīgā atšķirīgos pilsētas rajonos tika izvēlēti seši dažāda lieluma parauglaukumi ar atšķirīgām vietas apbūves īpatnībām, ielu un dzelzceļu tīkla blīvumu un transporta noslogojumu, vidi piesārņojošo objektu iespējamo ietekmi, kā arī citām, urbānu vidi raksturojošām īpatnībām. Substrāta izraisītas elpošanas metod…

Serological prevalence of toxoplasmosis in pregnant women in Luanda (Angola): Geospatial distribution and its association with socio-demographic and …

2020

We report a study on toxoplasmosis in pregnant women in Luanda, Angola, determining the seroprevalence, geospatial distribution and its association with socio-economic features, dietary habits and hygiene and health conditions. Anti-Toxoplasma gondii IgG and IgM were quantified in serum samples of women attended at the Lucrecia Paim Maternity Hospital between May 2016 and August 2017. The IgG avidity test and qPCR assay were used for dating the primary infection. Data were collected by questionnaire after written consent, and spatial distribution was assessed through a Kernel Density Function. The potential risk factors associated with Toxoplasma infection were evaluated using bivariate and…

An extended Benthic Quality Index for assessment of lake profundal macroinvertebrates: addition of indicator taxa by multivariate ordination and weig…

2014

AbstractThe chironomid Benthic Quality Index (BQI) is a widely used metric in assessments of lake status. The BQI is based on 7 indicator taxa, which like most profundal fauna, often occur sporadically in low densities. Hence, a major weakness of the index is that it cannot be calculated when indicator taxa are not captured. Thus, an extension of the BQI that incorporates more macroinvertebrate taxa is desirable. We used 2 statistical approaches (Detrended Correspondence Analysis and Weighted Averaging) to estimate new benthic quality indicator scores for profundal macroinvertebrate taxa and to construct modified BQIs called Profundal Invertebrate Community Metrics (PICMs). We calibrated th…

Presacral Myelolipoma

2014

Many reports have described adrenal myelolipomas but there have been only a few reports of extra-adrenal myelolipomas. We describe a 74-year-old woman who came to our observation for MRI of the lumbar spine for typical lumbar back pain. In addition to signs of mild scoliosis and spondylo disc arthrosis, MR imaging revealed a presacral mass showing a heterogeneously high signal in all pulse sequences and almost completely suppressed on inversion recovery sequences for fat tissue. CT imaging confirmed the fatty nature of the lesion and no signs of bone involvement. These findings were most consistent with a diagnosis of a rare presacral myelolipoma as confirmed at histopathologic analysis. T…