Estimation of cell distribution heterogeneity at toxicological experiments with clonal cultures of benthic diatoms

An increase in anthropogenic pressure on coastal water areas requires regular monitoring of marine ecosystems. The appropriate bioindicators for indirect assessment of the quality of the near-shore environment are benthic diatom algae, which are a key element of coastal communities and are highly sensitive to environmental impact. Changes in the development of diatoms under the influence of various toxicants may be used as relevant tool for monitoring of marine environment quality. However, scientific and methodological approaches to application of benthic diatom algae as test objects remain unstudied. One of the important methodological problems is the assessment of the significance of the samples in experimental vessels when counting cells abundance at different stages of toxicological test. The study is focused on assessment of the statistical significance of the equality of the initial mean number of cells of clonal culture inoculum placed into each of the replicates, as well as the statistical uniformity of cell distribution over the entire bottom area of Petri dishes. We used clonal cultures of three benthic diatom species belonging to different classes of Bacillariophyta: Thalassiosira excentrica Cleve, 1903 (Coscinodiscophycea), Ardissonea crystallina (C. Agardh) Grunow, 1880 (Fragilariophyceae), and Pleurosigma aestuarii (Bréb. in Kütz.) W. Smith, 1853 (Bacillariophyceae). They significantly differ in valve morphology and life history (floating in water mass, attached to substrate, and motile). The results of statistical comparison of cell number variability in the experiment for all studied species confirmed the absence of significant differences between the mean values of the tested parameter at a standard significance level (0.05). It was shown that despite specific differences in cell growth rate during the experiment, the variability in cell number in the microscope viewing fields varies irregularly. The highest value of the variability coefficient was observed on the 5th day for the small-sized species T. excentrica (Cv = 42…55 %), and the lowest variability – for the large-cell species A. crystallina (Cv = 27…31 %). The absence of significant differences in cell number between three replicates (for each species) was established both during the initial placing of inoculum into the dishes and on the following days of the experiment. The conclusion is applicable for each of diatom species studied, which allows to consider all replicates as subsamples of the replicate sample and to average the results obtained at different stages of the toxicological experiment. The uniformity of cell distribution throughout experimental dishes bottom, which does not depend on species and absolute cell number, was statistically proven. The results obtained allow to statistically reliably estimate the changes in cell number at different stages of toxicological experiment according to replicate sampling, based on cell counting in a limited number of viewing fields.

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Whole-brain 3D MR fingerprinting brain imaging: clinical validation and feasibility to patients with meningioma

Magnetic Resonance Materials in Physics Biology and Medicine ◽

10.1007/s10334-021-00924-1 ◽

2021 ◽

Author(s):

Thomaz R. Mostardeiro ◽

Ananya Panda ◽

Robert J. Witte ◽

Norbert G. Campeau ◽

Kiaran P. McGee ◽

...

Keyword(s):

White Matter ◽

Statistical Significance ◽

Relaxation Times ◽

Brain Structures ◽

Centrum Semiovale ◽

In Vivo Evaluation ◽

Whole Brain ◽

Mean Values ◽

Caudate Head

Abstract Purpose MR fingerprinting (MRF) is a MR technique that allows assessment of tissue relaxation times. The purpose of this study is to evaluate the clinical application of this technique in patients with meningioma. Materials and methods A whole-brain 3D isotropic 1mm3 acquisition under a 3.0T field strength was used to obtain MRF T1 and T2-based relaxometry values in 4:38 s. The accuracy of values was quantified by scanning a quantitative MR relaxometry phantom. In vivo evaluation was performed by applying the sequence to 20 subjects with 25 meningiomas. Regions of interest included the meningioma, caudate head, centrum semiovale, contralateral white matter and thalamus. For both phantom and subjects, mean values of both T1 and T2 estimates were obtained. Statistical significance of differences in mean values between the meningioma and other brain structures was tested using a Friedman’s ANOVA test. Results MR fingerprinting phantom data demonstrated a linear relationship between measured and reference relaxometry estimates for both T1 (r2 = 0.99) and T2 (r2 = 0.97). MRF T1 relaxation times were longer in meningioma (mean ± SD 1429 ± 202 ms) compared to thalamus (mean ± SD 1054 ± 58 ms; p = 0.004), centrum semiovale (mean ± SD 825 ± 42 ms; p < 0.001) and contralateral white matter (mean ± SD 799 ± 40 ms; p < 0.001). MRF T2 relaxation times were longer for meningioma (mean ± SD 69 ± 27 ms) as compared to thalamus (mean ± SD 27 ± 3 ms; p < 0.001), caudate head (mean ± SD 39 ± 5 ms; p < 0.001) and contralateral white matter (mean ± SD 35 ± 4 ms; p < 0.001) Conclusions Phantom measurements indicate that the proposed 3D-MRF sequence relaxometry estimations are valid and reproducible. For in vivo, entire brain coverage was obtained in clinically feasible time and allows quantitative assessment of meningioma in clinical practice.

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Use of raw Euphorbia tirucalli extract for inhibition of ascitic Ehrlich tumor

Revista do Colégio Brasileiro de Cirurgiões ◽

10.1590/0100-69912016001005 ◽

2016 ◽

Vol 43 (1) ◽

pp. 18-21 ◽

Cited By ~ 5

Author(s):

Orlando José dos Santos ◽

Euler Nicolau Sauaia Filho ◽

Flávia Raquel Fernandes do Nascimento ◽

Francisco Cardoso Silva Júnior ◽

Eder Magalhães Silva Fialho ◽

...

Keyword(s):

Bone Marrow ◽

Tumor Cell ◽

Ascitic Fluid ◽

Statistical Significance ◽

Isotonic Saline ◽

Cell Number ◽

Fluid Volume ◽

Control Group ◽

Ehrlich Tumor ◽

Euphorbia Tirucalli

Objective: to evaluate the effect of the Euphorbia tirucalli hydroalcoholic extract (ETHE) on the development of Ehrlich Tumor, in its ascitic form. Methods: we intraperitoneally inoculated 15 Swiss mice with 10.44 x 107 cells of Ehrlich Tumor and divided them in two groups one day after: ETHE Group (eight mice), treated with a dosage of 125 mg/kg/day of EHTE for five days; and Control Group (seven mice), treated only with 0.9% isotonic saline solution over the same period. The treatment was done by gavage. Ten days after inoculation, four mice from each group were sacrificed for quantification of tumor cell number, ascitic fluid volume and bone marrow cell number. The remaining animals were maintained to evaluate survival. Results: The ascitic fluid volume and the tumor cell number were decreased in the ETHE group when compared with the control group, but with no statistical significance. On the other hand, survival was higher in the ETHE group, as well as the number of bone marrow cells. Conclusion: Treatment with ETHE after inoculation of Ehrlich Tumor decreases its development and increases survival and the bone marrow cellularity, thus reducing the myelosuppression present in the Ehrlich Tumor bearing mice.

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Inhibitory effect of benthic diatom species on three aquaculture pathogenic vibrios

Algal Research ◽

10.1016/j.algal.2017.09.004 ◽

2017 ◽

Vol 27 ◽

pp. 131-139 ◽

Cited By ~ 7

Author(s):

Ceres A. Molina-Cárdenas ◽

M. del Pilar Sánchez-Saavedra

Keyword(s):

Inhibitory Effect ◽

Benthic Diatom ◽

Diatom Species ◽

Pathogenic Vibrios

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Impact of satellite viewing swath width on global and regional aerosol optical thickness statistics and trends

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-6-10117-2013 ◽

2013 ◽

Vol 6 (6) ◽

pp. 10117-10163 ◽

Cited By ~ 2

Author(s):

P. R. Colarco ◽

R. A. Kahn ◽

L. A. Remer ◽

R. C. Levy

Keyword(s):

Optical Thickness ◽

Statistical Significance ◽

Sampling Strategy ◽

Aerosol Optical Thickness ◽

Mean Values ◽

Sampling Artifacts ◽

Aerosol Loading ◽

Decadal Scale ◽

Along Track ◽

The Impact

Abstract. We use the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite aerosol optical thickness (AOT) product to assess the impact of reduced swath width on global and regional AOT statistics and trends. Ten different sampling strategies are employed, in which the full MODIS dataset is sub-sampled with various narrow-swath (~400–800 km) and curtain-like (~10 km) along-track configurations. Although view-angle artifacts in the MODIS AOT retrieval confound direct comparisons between averages derived from different sub-samples, careful analysis shows that with many portions of the Earth essentially unobserved, the AOT statistics of these sub-samples exhibit significant regional and seasonal biases. These AOT spatial sampling artifacts comprise up to 60% of the full-swath AOT value under moderate aerosol loading, and can be as large as 0.1 in some regions under high aerosol loading. Compared to full-swath observations, narrower swaths exhibit a reduced ability to detect AOT trends with statistical significance, and for curtain-like sampling we do not find any statistically significant decadal-scale trends at all. An across-track sampling strategy obviates the MODIS view angle artifact, and its mean AOT converges to the full-swath mean values for sufficiently coarse spatial and temporal aggregation. Nevertheless, across-track sampling has significant seasonal-regional sampling artifacts, leading to biases comparable to the curtain-like along-track sampling, lacks sufficient coverage to assign statistical significance to aerosol trends, and is not achievable with an actual narrow-swath or curtain-like instrument. These results suggest that future aerosol satellite missions having significantly less than full-swath viewing are unlikely to sample the true AOT distribution well enough to determine decadal-scale trends or to obtain the statistics needed to reduce uncertainty in aerosol direct forcing of climate.

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Intestinal Microsporidiosis Among HIV/AIDS Patients Receiving Antiretroviral Therapy in Sana’a City, Yemen: First Report on Prevalence and Predictors

10.21203/rs.3.rs-684810/v1 ◽

2021 ◽

Author(s):

Kwkab A. R. Al-Barhami ◽

Rashad Abdul-Ghani ◽

Salah A. Al-Qobati

Keyword(s):

Risk Factors ◽

Antiretroviral Therapy ◽

Large Scale ◽

Statistical Significance ◽

Univariate Analysis ◽

Cell Counting ◽

Cd4 Cells ◽

Aids Patients ◽

Intestinal Microsporidiosis ◽

Hiv Aids

Abstract Background: Intestinal microsporidiosis is an opportunistic infection associated with persistent diarrhea among HIV/AIDS patients. In Yemen, however, its epidemiology is unknown. Therefore, this study determined its prevalence and predictors among HIV/AIDS patients receiving antiretroviral therapy (ART) in Sana'a city, Yemen.Methods: This cross-sectional study included 402 patients receiving ART at Al-Jomhori Educational Hospital in Sana'a from November 2019 to December 2020. Data about demographics, clinical characteristics and risk factors were collected using a pre-designed questionnaire. Stool samples were collected and examined for microsporidian spores using the Gram-chromotrope Kinyoun staining. Blood samples were also collected and used for CD4 cell counting by flow cytometry. Univariate analysis was used to test the association of patients’ characteristics and risk factors with intestinal microsporidiosis. Multivariable logistic regression was then used to identify the independent predictors of infection. Statistical significance was considered at P-values <0.05. Results: Intestinal microsporidiosis was prevalent among 14.2% (57/402) of HIV/AIDS patients but was not significantly associated with any of the studied demographics, source of drinking water, bathing and/or swimming outdoors, contact with soil, presence of domestic animals or indiscriminate defecation. However, it was significantly associated with diarrhea (OR=3.4, 95% CI: 1.7–6.6; P=0.001) and <200 CD4 cells/µl (OR=2.7, 95% CI: 1.5–5.0; P=0.001). The significant independent predictors of infection were <200 CD4 cells/µl (AOR=3.2, 95% CI: 1.5–6.9; P=0.003), not washing hands after contacting soil (AOR=2.5, 95% CI: 1.1–5.4; P=0.026) and before eating (AOR=3.1, 95% CI: 1.5–6.4; P=0.003), eating unwashed raw produce (AOR=2.5, 95% CI: 1.2–5.3; P=0.017) and absence of indoor latrines (AOR=6.2, 95% CI: 1.5–25.9; P=0.012).Conclusions: The prevalence of intestinal microsporidiosis among HIV/AIDS patients in Sana'a is high and comparable to that several other countries, being prevalent among approximately 14.0% of patients and significantly associated with diarrhea. It could be predicted among patients who have <200 CD4 cells/µl, poor hand hygiene after contacting soil and before eating, usually eat unwashed raw produce and do not possess indoor latrines. Large-scale studies on its epidemiology and predictors among HIV/AIDS patients across the country are warranted.

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Cell-Tak coating may cause mis-normalization of Seahorse metabolic flux data

10.1101/2021.03.19.436150 ◽

2021 ◽

Author(s):

Michal Šíma ◽

Stanislava Martínková ◽

Anežka Kafková ◽

Jan Pala ◽

Jan Trnka

Keyword(s):

Metabolic Flux ◽

Cell Number ◽

Cell Counting ◽

Fluorescent Detection ◽

Data Normalization ◽

Tissue Samples ◽

Flux Data ◽

Research Areas ◽

Healthy State ◽

A Cell

Metabolic flux investigations of cells and tissue samples are a rapidly advancing tool in diverse research areas. Reliable methods of data normalization are crucial for an adequate interpretation of results and to avoid a misinterpretation of experiments and incorrect conclusions. The most common methods for metabolic flux data normalization are to cell number, DNA and protein. Data normalization may be affected by a variety of factors, such as density, healthy state, adherence efficiency, or proportional seeding of cells. The mussel-derived adhesive Cell-Tak is often used to immobilize poorly adherent cells. Here we demonstrate that this coating may strongly affect the fluorescent detection of DNA leading to an incorrect and highly variable normalization of metabolic flux data. Protein assays are much less affected and cell counting can virtually completely remove the effect of the coating. Cell-Tak coating also affects cell shape in a cell line-specific manner and may change cellular metabolism. Based on these observations we recommend cell counting as a gold standard normalization method for Seahorse metabolic flux measurements with protein content as a reasonable alternative.

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Analysis of the type material of Achnanthes minutissima var. macrocephala (Bacillariophyta) and description of two new small capitate Achnanthidium species from Europe and the Himalaya

Plant Ecology and Evolution ◽

10.5091/plecevo.2019.1628 ◽

2019 ◽

Vol 152 (2) ◽

pp. 340-350

Author(s):

Carlos E. Wetzel ◽

Ingrid Jüttner ◽

Smriti Gurung ◽

Luc Ector

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Benthic Diatom ◽

Original Material ◽

Diatom Species ◽

The World ◽

Freshwater Habitats ◽

The Himalaya ◽

Scanning Electron ◽

Achnanthes Minutissima

Background and aims – Two unknown benthic diatom species belonging to the genus Achnanthidium Kütz., and found in French and Nepalese freshwater habitats, were investigated. Both species are here described as new and compared with the original material of Achnanthes minutissima var. macrocephala Hust. [≡ Achnanthidium macrocephalum (Hust.) Round & Bukht.] from Indonesia. Methods – The morphology of three small and capitate Achnanthidium species was investigated using light microscopy (LM) and scanning electron microscopy (SEM). Key results – Achnanthidium coxianum sp. nov. (from the Himalaya) belongs to the group of species with hooked terminal raphe endings, while Achnanthidium peetersianum sp. nov. (from France) has variable terminal raphe endings which are usually slightly bent. Achnanthidium macrocephalum is a much rarer species and illustrations concerning its identity in the literature do not conform to the type studied here. Conclusions – The three species are similar in LM but clearly distinct in SEM. The shape of the areolae and terminal raphe endings separate the species. Achnanthidium macrocephalum has often been misidentified in studies from many areas of the world. It is similar to the new species in valve outline and in its small dimensions.

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Frequency of number of roots and root canals of maxillary first premolar teeth.

The Professional Medical Journal ◽

10.29309/tpmj/2021.28.10.6290 ◽

2021 ◽

Vol 28 (10) ◽

pp. 1513-1518

Author(s):

Munawar Aziz Khattak ◽

Sana Arbab ◽

Syed Amjad Shah

Keyword(s):

Statistical Significance ◽

Maxillofacial Surgery ◽

P Value ◽

Cross Sectional ◽

Mean Values ◽

Khyber Pakhtunkhwa ◽

Root Canals ◽

India Ink ◽

Different Levels ◽

Chamber Floor

Objective: To determine the frequency of the number of roots and root canals in a sample of 250 extracted maxillary first premolar teeth of patients visiting Peshawar Dental College and Hospital Khyber Pakhtunkhwa. Study Design: Cross Sectional. Setting: Department of Oral Biology, Peshawar Dental College and Hospital Khyber Pakhtunkhwa. Period: April 2016 to December 2016. Material & Methods: A total of 250 extracted human maxillary first premolars were collected from the Department of Oral & Maxillofacial Surgery, Peshawar Dental College, and Hospital Khyber Pakhtunkhwa. All teeth were visually inspected to count the number of roots. Subsequently, the access cavity was prepared, and pulp extirpated from each tooth. Endodontic explorer was used to locating the canal orifice(s) at the pulp chamber floor. Later the root canal orifices were injected with India ink to stain the canals. After that roots of teeth were sectioned at different levels to note down the number of canals. Data were analyzed using SPSS version 19. The statistical significance of the variations from mean values was considered significant if the p-value was less than 0.05. Results: Out of 250 maxillary first premolar teeth, 44.8% had one root, 40.4% had two separate and 12.8% had two fused roots. Three roots were seen in 2.0% teeth. Two root canals were present in the vast majority (70.4%), whereas one and three root canals were seen in 27.6% and 2.0% teeth, respectively. The correlation between the number of roots and root canals of maxillary first premolar teeth was highly significant. Conclusions: There was a high frequency of maxillary first premolars with two roots and two root canals.

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Periodontal inflammation correlates with systemic inflammation and insulin resistance in patients with recent diagnosis of type 2 diabetes

ARS MEDICA Revista de Ciencias Médicas ◽

10.11565/arsmed.v44i1.1524 ◽

2019 ◽

Vol 44 (1) ◽

pp. 6-12

Author(s):

Natacha Oyarzo ◽

María Riveros ◽

Constanza Andaur ◽

Jessica Liberona ◽

Víctor Cortés

Keyword(s):

Insulin Resistance ◽

Systemic Inflammation ◽

Statistical Significance ◽

Mean Values ◽

Reactive Protein ◽

Inflammatory Parameters ◽

Periodontal Inflammation ◽

Probing Depth ◽

Recent Diagnosis

Background: diabetes and periodontitis are common comorbidities; however, the clinical implications of this association remain only partially known. This study was aimed to characterize the periodontal status of type 2 diabetic (T2D) patients and its correlation with metabolic and inflammatory parameters. Methods: patients (n = 30) with 5 or less years since the diagnosis of T2D (18 – 65 years old) were recruited. Anthropometric (Body Mass Index, BMI), metabolic (fasting glucose, glycated hemoglobin, insulin, HOMA-IR, HDL, LDL and total cholesterol, triglycerides) and inflammatory parameters (ultrasensitive C reactive protein, usCRP) were quantified. Periodontal evaluation included clinical attachment level (CAL), probing depth (PD), gingival level (GL) and bleeding on probing (BOP) average. Statistical significance was assessed by Mann-Whitney and Spearman correlation tests. Results: mean values of BOP, CAL, PD and GL were 39.3, 2.8, 2.8, and 0.1, respectively. BOP significantly correlated with BMI and HOMA-IR and was higher in patients with elevated usCRP >3 mg/L (p<0.05). Age and duration of T2D directly and inversely correlated with CAL and GL, respectively. BOP correlated with HOMA-IR and usCRP but not with patients´age, duration of T2D or BMI. Conclusions: in patients with recent diagnosis of T2D, BOP is associated with usCRP and HOMA-IR levels, suggesting that periodontal inflammation promotes insulin resistance possibly by increasing systemic inflammation.

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Testing of primary stability of the Activ® L intervertebral disc prosthesis in cadaver bone and comparison of the two different anchoring concepts – keel and spike anchoring

10.21203/rs.3.rs-16688/v1 ◽

2020 ◽

Author(s):

Christoph von Schulze Pellengahr ◽

Wolfram Teske ◽

Saurabh Kapoor ◽

Alexander Klein ◽

Bernd Wegener ◽

...

Keyword(s):

Lumbar Spine ◽

Intervertebral Disc ◽

Statistical Significance ◽

Primary Stability ◽

Longitudinal Axis ◽

Disc Prosthesis ◽

Mean Values ◽

Intervertebral Disc Prosthesis ◽

Flexion Extension ◽

Micro Motion

Abstract Background: High primary stability is the fundamental prerequisite for safe osseointegration of cementless intervertebral disc prosthesis. The aim of our study was to determine the primary stability of intervertebral disc prosthesis with two different anchoring concepts – keel and spike anchoring. Methods: 10 human cadaveric lumbar spine specimens with an ActivL intervertebral disc prosthesis (5 x keel anchoring, 5 x spike anchoring) were tested on a spine simulator. Under axial load, moments of flexion, extension, left and right bending and axial rotation were applied on the lumbar spine specimens through a defined three-dimensional movement program as per ISO 2631 and ISO/CD 18192-1.3 standards. Micro-motion of the implant was measured in every axis for both anchor types and compared using statistical test for significance after calculating 95% confidence intervals. Results: In the transverse axis, the keel anchoring concept showed lower mean values of micro-motion , which was statistically significant (p<0.05) compared to spike anchoring concept. In the sagittal axis, the results were again in favour of the keel anchoring, but did not reach statistical significance (p>0.05). The highest micro-motion values were observed in the longitudinal axis. Both concepts showed values around the threshold of primary stability (150 μm) with the spike concept showing lower mean values, but without a statistically significant difference.Conclusions: Both types of anchors met the criteria of primary stability. The keel anchoring shows a slight advantage compared to anchoring with spikes. Direct postoperative active mobilization doesn’t seem to compromise the primary stability of the prosthesis.

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