34 research outputs found
Prolonged light exposure induces widespread phase shifting in the circadian clock and visual pigment gene expression of the Arvicanthis ansorgei retina.
PURPOSE: Prolonged periods of constant lighting are known to perturb circadian clock function at the molecular, physiological, and behavioral levels. However, the effects of ambient lighting regimes on clock gene expression and clock outputs in retinal photoreceptors--rods, cones and intrinsically photosensitive retinal ganglion cells--are only poorly understood.
METHODS: Cone-rich diurnal rodents (Muridae: Arvicanthis ansorgei) were maintained under and entrained to a 12 h:12 h light-dark cycle (LD; light: ~300 lux). Three groups were then examined: control (continued maintenance on LD); animals exposed to a 36 h dark period before sampling over an additional 24 h period of darkness (DD); and animals exposed to a 36 h light period before sampling over an additional 24 h period of light (~300 lux, LL). Animals were killed every 3 or 4 h over 24 h, their retinas dissected, and RNA extracted. Oligonucleotide primers were designed for the Arvicanthis clock genes Per1, Per2, Cry1, Cry2, and Bmal1, and for transcripts specific for rods (rhodopsin), cones (short- and mid-wavelength sensitive cone opsin, cone arrestin, arylalkylamine N-acetyltransferase) and intrinsically photosensitive retinal ganglion cells (melanopsin). Gene expression was analyzed by real-time PCR.
RESULTS: In LD, expression of all genes except cone arrestin was rhythmic and coordinated, with acrophases of most genes at or shortly following the time of lights on (defined as zeitgeber time 0). Arylalkylamine N-acetyltransferase showed maximal expression at zeitgeber time 20. In DD conditions the respective profiles showed similar phase profiles, but were mostly attenuated in amplitude, or in the case of melanopsin, did not retain rhythmic expression. In LL, however, the expression profiles of all clock genes and most putative output genes were greatly altered, with either abolition of daily variation (mid-wavelength cone opsin) or peak expression shifted by 4-10 h.
CONCLUSIONS: These data are the first to provide detailed measures of retinal clock gene and putative clock output gene expression in a diurnal mammal, and show the highly disruptive effects of inappropriate (nocturnal) lighting on circadian and photoreceptor gene regulationjournal articleresearch support, non-u.s. gov't20132013 05 21importe
Biochemical profile of the proteolytic processes in blood serum and in the prostatic lodge fluid at the patients with transvesical adenomectomy with the usage of endourethral drainage
IP USMF "Nicolae Testemiţanu", IMSP Spitalul Clinic Municipal "Sf. Treime", Secţia Urologie, Al VI-lea Congres de Urologie, Dializă şi Transplant Renal din Republica Moldova cu participare internaţională (21-23 octombrie 2015)Studiului constă în evaluarea proceselor proteolitice în serul sanguin în perioada pre - şi postoperatorie la pacienţii cu AP şi în eliminările din loja după
adenomectomie întru determinarea rolului lorpredictiv în evoluţia proceselor lezionare concomitente şi monitorizării hemostazeiîn loja prostatică utilizând
drenarea endouretrală a lo je i. Cercetările actualului studiu sunt de tip prospectiv fiind bazate pe un eşantion de 65 bărbaţi, conlocuitori ai R. Moldova, cu
vârsta între 50-75 ani. Eşantionul general de studiu a fost divizat în două loturi specifice Lf - lotul de cercetare cu AP (n=45)şi LM - lotul m artor(n=20). în
lotul de cercetare, sa inclus pacienţi cu AP rezolvat chirurgical prin metoda transvezicală în modificarea elaborată şi propusă de noi, [3] (fig.1). Sa constatat
că în cadrul evoluţiei AP are loc creşterea pronunţată a funcţionalităţii majorităţii enzimelor proteolitice atât în serul sanguin cât şi în eliminările din lojă. Sa
stabilit unii parametrii aşa ca SN şi MMM în serul sanguin şi la nivel de lojă, servind drept marcheri ale prezenţei intoxicaţiei endogene şi toxicităţii din serul
sanguin ca rezultat a proceselor proteolitice derulate în cadrul AP şi postoperatoriu. Este relevantă importanţa rezultatelor obţinute privind sensibilitatea
diferită a proteazelor acide în AP, fapt ce confirmă că utilizarea drenării lojei deschide noi posibilităţi a unei tactici medico-chirurgicale şi terapeutice
alternative în optimizarea unei hemostaze la nivel de lojă.Summary
The aim of study is to appreciate proteolytic processes both in blood serum and the lodge drainage fluid in the pre-and post-operative period in patients
with BPH after adenomectomy in order to identify their predictive role in the development of concomitant injurious processes and monitoring of the
hemostasis in the prostatic lodge using endourethral drainage. Current research is a prospective study based on a sample of 65 men from the Republic of
Moldova, aged 50-75 years. General study sample was divided into two specific lots: Rg - research group with PA, (n = 45) and Cg - control group (n = 20).
The research group included patients with PA surgically solved by the changed transvesical method developed and proposed by us. It was found that in the
evolution of PA most proteolytic enzymes functionality is increasing both in the blood serum and in the fluid drained from the lodge. Were determined
some parameters such as SN and MMM in blood serum and in the lodge, serving as markers of endogenous intoxication presence and toxicity of blood
serum as a result of proteolytic processes developed within BPH and postoperatively. The results revealed the importance of the different sensitivity of the
acidic proteases in BPH, which confirms that the use of lodge drainage opens new possibilities of alternative surgical and therapeutic tactics to optimize
the hemostasis in the prostatic lodge
The estimation of the peculiarities and the activity degree of the consisting inflammatory processes in the benign prostatic hyperplasia
Secţia Urologie, IMSP Spitalul Clinic Municipal “ Sf. Treime”, Catedra Morfopatologie, USMF „N. Testemiţanu”, Secţia Ştiinţifică Morfopatologie, IMSP Institutul de Cercetări Ştiinţifice în Domeniul Ocrotirii Sănătăţii Mamei şi Copilului, Catedra Urologie şi Nefrologie Chirurgicală, USMF „N. Testemiţanu”, Al V-lea Congres de Urologie, Dializă şi Transplant Renal din Republica Moldova cu participare internaţională (1-13 iunie 2011)Summary. The conducted study has the aim to estimate the histopathological peculiarities of the inflammatory processes, evaluated in prostatic nodular hyperplasia, the character and the activity of these processes in the area of nodular hyperplasia structures, and the border limit in the adenectomy. The results of the morphopathological study allowed detailed diagnosis of the prostatic hyperplasia. Severe modifications of inflammatory origin and considerable implications of the structural-architectonical components indicate concomitant persisting or coexisting of chronic or acute prostatitis. The establishment of the lesion character, activity degree of the inflammatory process, saving border limit in the surgical management regarding the residual cavity of cleavage and postoperative prognosis was the second aim of the study. It facilitates the choice of the best therapeutic and surgical approach. The character of the inflammatory processes coexisting with prostatic benign hyperplasia was evaluated. A clinical-morphological concept of inflammatory associations in prostate benign hyperplasia was formulated
Human organotypic retinal cultures (HORCs) as a chronic experimental model for investigation of retinal ganglion cell degeneration
There is a growing need for models of human diseases that utilise native, donated human tissue in order to model disease processes and develop novel therapeutic strategies. In this paper we assessed the suitability of adult human retinal explants as a potential model of chronic retinal ganglion cell (RGC) degeneration. Our results confirmed that RGC markers commonly used in rodent studies (NeuN, bIII Tubulin and Thy-1) were appropriate for labelling human RGCs and followed the expected differential expression patterns across, as well as throughout, the macular and para-macular regions of the retina. Furthermore, we showed that neither donor age nor post-mortem time (within 24 h) significantly affected the initial expression levels of RGC markers. In addition, the feasibility of using human post mortem donor tissue as a long-term model of RGC degeneration was determined with RGC protein being detectable up to 4 weeks in culture with an associated decline in RGC mRNA and significant, progressive, apoptotic labelling of NeuNþ cells. Differences in RGC apoptosis might have been influenced by medium compositions indicating that media constituents could play a role in supporting axotomised RGCs. We propose that using ex vivo human explants may prove to be a useful model for testing the effectiveness of neuroprotective strategies
Getting aligned on representational alignment
Biological and artificial information processing systems form representations
that they can use to categorize, reason, plan, navigate, and make decisions.
How can we measure the extent to which the representations formed by these
diverse systems agree? Do similarities in representations then translate into
similar behavior? How can a system's representations be modified to better
match those of another system? These questions pertaining to the study of
representational alignment are at the heart of some of the most active research
areas in cognitive science, neuroscience, and machine learning. For example,
cognitive scientists measure the representational alignment of multiple
individuals to identify shared cognitive priors, neuroscientists align fMRI
responses from multiple individuals into a shared representational space for
group-level analyses, and ML researchers distill knowledge from teacher models
into student models by increasing their alignment. Unfortunately, there is
limited knowledge transfer between research communities interested in
representational alignment, so progress in one field often ends up being
rediscovered independently in another. Thus, greater cross-field communication
would be advantageous. To improve communication between these fields, we
propose a unifying framework that can serve as a common language between
researchers studying representational alignment. We survey the literature from
all three fields and demonstrate how prior work fits into this framework.
Finally, we lay out open problems in representational alignment where progress
can benefit all three of these fields. We hope that our work can catalyze
cross-disciplinary collaboration and accelerate progress for all communities
studying and developing information processing systems. We note that this is a
working paper and encourage readers to reach out with their suggestions for
future revisions.Comment: Working paper, changes to be made in upcoming revision
Novel Rodent Models for Macular Research
BACKGROUND: Many disabling human retinal disorders involve the central retina, particularly the macula. However, the commonly used rodent models in research, mouse and rat, do not possess a macula. The purpose of this study was to identify small laboratory rodents with a significant central region as potential new models for macular research.
METHODOLOGY/PRINCIPAL FINDINGS: Gerbillus perpallidus, Meriones unguiculatus and Phodopus campbelli, laboratory rodents less commonly used in retinal research, were subjected to confocal scanning laser ophthalmoscopy (cSLO), fluorescein and indocyanine green angiography, and spectral-domain optical coherence tomography (SD-OCT) using standard equipment (Heidelberg Engineering HRA1 and Spectralis™) adapted to small rodent eyes. The existence of a visual streak-like pattern was assessed on the basis of vascular topography, retinal thickness, and the topography of retinal ganglion cells and cone photoreceptors. All three species examined showed evidence of a significant horizontal streak-like specialization. cSLO angiography and retinal wholemounts revealed that superficial retinal blood vessels typically ramify and narrow into a sparse capillary net at the border of the respective area located dorsal to the optic nerve. Similar to the macular region, there was an absence of larger blood vessels in the streak region. Furthermore, the thickness of the photoreceptor layer and the population density of neurons in the ganglion cell layer were markedly increased in the visual streak region.
CONCLUSIONS/SIGNIFICANCE: The retinal specializations of Gerbillus perpallidus, Meriones unguiculatus and Phodopus campbelli resemble features of the primate macula. Hence, the rodents reported here may serve to study aspects of macular development and diseases like age-related macular degeneration and diabetic macular edema, and the preclinical assessment of therapeutic strategies
Review of the techniques used in motor‐cognitive human‐robot skill transfer
Abstract A conventional robot programming method extensively limits the reusability of skills in the developmental aspect. Engineers programme a robot in a targeted manner for the realisation of predefined skills. The low reusability of general‐purpose robot skills is mainly reflected in inability in novel and complex scenarios. Skill transfer aims to transfer human skills to general‐purpose manipulators or mobile robots to replicate human‐like behaviours. Skill transfer methods that are commonly used at present, such as learning from demonstrated (LfD) or imitation learning, endow the robot with the expert's low‐level motor and high‐level decision‐making ability, so that skills can be reproduced and generalised according to perceived context. The improvement of robot cognition usually relates to an improvement in the autonomous high‐level decision‐making ability. Based on the idea of establishing a generic or specialised robot skill library, robots are expected to autonomously reason about the needs for using skills and plan compound movements according to sensory input. In recent years, in this area, many successful studies have demonstrated their effectiveness. Herein, a detailed review is provided on the transferring techniques of skills, applications, advancements, and limitations, especially in the LfD. Future research directions are also suggested
Eightfold increased membrane flux of NF 270 by O3 oxidation of natural humic acids without deteriorated permeate quality
BACKGROUND:
Membrane fouling by humic acids limits the water recovery of nanofiltration in drinking water production. This article investigates if membrane fouling can be reduced by decomposition of humic acids in the concentrate stream by O3 oxidation.
RESULTS:
At a specific O3 dose of 2.11 g O3 per g COD (17.0 g m-3 O3 (g) for 20 minutes), a COD reduction of 38% and a hydrophobic COD reduction of 69% is achieved. The membrane permeability of the ozonated solution by NF 270 membranes is higher (20.6 . 10-9 L s-1 m-2 Pa-1) than the permeability if the untreated solution is filtered (2.4 . 10-9 L s-1 m-2 Pa-1). The COD retention of the ozonated solution was similar to the retention of the untreated samples. The addition of H2O2 allows to obtain a better mineralization degree, i.e., UVA removal increased from 53% to 66% if H2O2 was added as from 10 minutes oxidation at the same molar flow rate as O3.
CONCLUSION:
O3 oxidation can substantially alleviate membrane fouling by humic acids in nanofiltration systems and the addition of H2O2 can slightly improve its decomposition.status: publishe