scholarly journals Microscopic and infrared spectroscopic comparison of the underwater adhesives produced by germlings of the brown seaweed species Durvillaea antarctica and Hormosira banksii

2016 ◽  
Vol 13 (117) ◽  
pp. 20151083 ◽  
Author(s):  
Simone Dimartino ◽  
David M. Savory ◽  
Sara J. Fraser-Miller ◽  
Keith C. Gordon ◽  
A. James McQuillan
Keyword(s):  
Developmental Stages ◽  
Brown Seaweed ◽  
Principal Component ◽  
Close Relative ◽  
Microscopy Imaging ◽  
Seaweed Species ◽  
Durvillaea Antarctica ◽  
Attachment Ability ◽  
Early Developmental

Adhesives from marine organisms are often the source of inspiration for the development of glues able to create durable bonds in wet environments. In this work, we investigated the adhesive secretions produced by germlings of two large seaweed species from the South Pacific, Durvillaea antarctica , also named ‘the strongest kelp in the word’, and its close relative Hormosira banksii . The comparative analysis was based on optical and scanning electron microscopy imaging as well as Fourier transform infrared (FTIR) spectroscopy and principal component analysis (PCA). For both species, the egg surface presents peripheral vesicles which are released soon after fertilization to discharge a primary adhesive. This is characterized by peaks representative of carbohydrate molecules. A secondary protein-based adhesive is then secreted in the early developmental stages of the germlings. Energy dispersive X-ray, FTIR and PCA indicate that D. antarctica secretions also contain sulfated moieties, and become cross-linked with time, both conferring strong adhesive and cohesive properties. On the other hand, H. banksii secretions are complemented by the putative adhesive phlorotannins, and are characterized by a simple mechanism in which all constituents are released with the same rate and with no apparent cross-linking. It is also noted that the release of adhesive materials appears to be faster and more copious in D. antarctica than in H. banksii . Overall, this study highlights that both quantity and quality of the adhesives matter in explaining the superior attachment ability of D. antarctica .

scholarly journals Alternative methods of replacement of laboratory animals in biomedical research

2018 ◽  
Vol 50 (3) ◽  
pp. 212
Author(s):  
N. G. KOSTOMITSOPOULOS (Ν.Γ. ΚΩΣΤΟΜΗΤΣΟΠΟΥΛΟΣ)
Keyword(s):  
Developmental Stages ◽  
Alternative Methods ◽  
Laboratory Animals ◽  
Quality Of Results ◽  
Scientific Value ◽  
Early Developmental ◽  
Biomedical Community ◽  
Data Banks

Society's sensitivity on the use of laboratory animals, the need for the improvement of the scientific value of the results and the high costs urged the biomedical community to look for alternative methodologies which could replace or reduce the number of animals being used or refine the existing experimental techniques. Replacement alternatives can be classified, according to the applied methology, in in vitro and immunological techniques and in methods which use «lower» organisms or vertebrates at early developmental stages, mathematical or computer models, human studies or data banks. Using replacement alternatives may raise a lot of problems such as the quality of results. Validation of these methods is a complicated and time consuming process with high but fair hurdles which aim at human safety.

Effect of embryo developmental stage and culture conditions on number and quality of ovine in vitro produced blastocysts

Zygote ◽  
2006 ◽  
Vol 14 (3) ◽  
pp. 181-187 ◽  
Author(s):  
R.M. Garcia-Garcia ◽  
V. Dominguez ◽  
A. Gonzalez-Bulnes ◽  
A. Veiga-Lopez ◽  
M.J. Cocero
Keyword(s):  
Developmental Stage ◽  
Developmental Stages ◽  
Developmental Rate ◽  
Defined Medium ◽  
Culture Conditions ◽  
Cell Groups ◽  
Early Developmental

SummaryThis study evaluated the final output and quality of in vitro produced blastocysts derived from in vivo recovered sheep embryos cultured at various early developmental stages to blastocyst. A total of 270 embryos were recovered from the oviduct, at different days of the early luteal phase, and were classified into three different developmental stages: 2- to 4-cell (n = 93); 5- to 8-cell (n = 92) and 9- to 12-cell (n = 85). The effect of culture conditions was studied, at the same time, by randomly allocating the embryos to one of four groups: three groups of culture with fresh oviduct monolayers (2, 4 and 5 days old) and a fourth group with 2-day monolayers derived from frozen-thawed oviduct cells. Two control groups were established: first, embryos cultured in semi-defined medium (n = 29) and, second, blastocysts obtained in vivo and cryopreserved (n = 43). Influence on blastocyst yield of embryo developmental stage at the start of culture was statistically significant (p < 0.001). Two- to four-cell embryos showed a significantly lower developmental rate (67.7%) than the 5- to 8-cell (83.6%; p < 0.001) and 9- to 12-cell groups (90.5%; p < 0.0001) and lower quality in terms of blastocyst cryotolerance (56.0 vs. 83.7%; p < 0.005). There were no detected effects relating to the age or handling of the monolayer on the embryo developmental rate, but the day of blastocyst appearance was different between embryos cultured on monolayers derived from fresh or frozen-thawed cells (p < 0.0001); the main influence was on the group of 9- to 12-cell embryos (p < 0.0001). Current results confirm the temporal sensitivities of sheep embryos to in vitro culture, regardless of the culture conditions.

Correlated Studies of Cellular Interactions Using TEM, Freeze Etching, and SEM

1974 ◽  
Vol 32 ◽  
pp. 320-321
Author(s):  
J. P. Revel
Keyword(s):  
Developmental Stages ◽  
Three Dimensional ◽  
Cell Movement ◽  
Cellular Interactions ◽  
Serial Sections ◽  
Cell Sheets ◽  
Freeze Etching ◽  
Early Developmental

Movement of individual cells or of cell sheets and complex patterns of folding play a prominent role in the early developmental stages of the embryo. Our understanding of these processes is based on three- dimensional reconstructions laboriously prepared from serial sections, and from autoradiographic and other studies. Many concepts have also evolved from extrapolation of investigations of cell movement carried out in vitro. The scanning electron microscope now allows us to examine some of these events in situ. It is possible to prepare dissections of embryos and even of tissues of adult animals which reveal existing relationships between various structures more readily than used to be possible vithout an SEM.

Review of early developmental stages of trilobites and agnostids from the Barrandian area (Czech Republic)

2017 ◽  
Vol 186 (1) ◽  
pp. 103-112
Author(s):  
Lukáš Laibl ◽  
Oldřich Fatka
Keyword(s):  
Czech Republic ◽  
Developmental Stages ◽  
History Of Research ◽  
Early Developmental Stages ◽  
History Of ◽  
Barrandian Area ◽  
Early Developmental

This contribution briefly summarizes the history of research, modes of preservation and stratigraphic distribution of 51 trilobite and five agnostid taxa from the Barrandian area, for which the early developmental stages have been described.

Multivariate micropollutants analysis in marine waters

1995 ◽  
Vol 32 (9-10) ◽  
pp. 341-348
Author(s):  
V. Librando ◽  
G. Magazzù ◽  
A. Puglisi
Keyword(s):  
Multivariate Data Analysis ◽  
Partial Least Squares Regression ◽  
Environmental Chemistry ◽  
Sampling Site ◽  
Principal Component ◽  
Least Squares Regression ◽  
Organic Micropollutants ◽  
Suspended Material ◽  
The Difference

The monitoring of water quality today provides a great quantity of data consisting of the values of the parameters measured as a function of time. In the marine environment, and especially in the suspended material, increasing importance is being given to the presence of organic micropollutants, particularly since some are known to be carcinogenic. As the number of measured parameters increases examining the data and their consequent interpretation becomes more difficult. To overcome such difficulties, numerous chemometric techniques have been introduced in environmental chemistry, such as Multivariate Data Analysis (MVDA), Principal Component Analysis (PCA) and Partial Least Squares Regression (PLSR). The use of the first technique in this work has been applied to the interpretation of the quality of Augusta bay, by measuring the concentration of numerous organic micropollutants, together with the classical water pollution parameters, in different sites and at different times. The MVDA has highlighted the difference between various sampling sites whose data were initially thought to be similar. Furthermore, it has allowed a choice of more significant parameters for future monitoring and more suitable sampling site locations.

scholarly journals Exploratory Monitoring of the Quality and Authenticity of Commercial Honey in Ecuador

Foods ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 105 ◽  
Author(s):  
Lorena Salvador ◽  
Michelle Guijarro ◽  
Daniela Rubio ◽  
Bolívar Aucatoma ◽  
Tanya Guillén ◽  
...  
Keyword(s):  
Honey Bees ◽  
Reducing Sugars ◽  
Conductivity Measurement ◽  
Principal Component ◽  
Economic Importance ◽  
Critical Problem ◽  
Spectroscopic Analyses ◽  
Chemical Threats ◽  
Raman And Ir Spectroscopy

Honey is one of the oldest sweetening foods and has economic importance, making this product attractive to adulteration with cheap sugars. This can cause a critical problem in the honey industry and a possible health risk. The present work has the aim of evaluating the authenticity of honey commercialized in two different provinces of Ecuador (Pichincha and Loja) by performing physicochemical and spectroscopic analyses. For this study 25 samples were collected from different places and markets and characterized by water, sucrose, reducing sugars and electric conductivity measurement. Also, their Raman and Infrared (IR) spectra were recorded and analysed using a Principal Component Analysis (PCA) in order to verify the quality of the honeys. In addition, a screening of several pesticides was performed in order to verify possible chemical threats to human health and honey bees. It was found that 8 samples have a deviation from the Standard established parameters. Two of them have a high difference in the content of sucrose and reducing sugars, which are located deviated from all the other samples in the PCA of the applied vibrational spectroscopy (IR/Raman), shaping two clear clusters. The results show that Raman and IR spectroscopy is appropriate techniques for the quality control of honey and correlates well with the physicochemical analyses.

scholarly journals The Effect of an Anthropogenic Magnetic Field on the Early Developmental Stages of Fishes—A Review

2021 ◽  
Vol 22 (3) ◽  
pp. 1210
Author(s):  
Krzysztof Formicki ◽  
Agata Korzelecka-Orkisz ◽  
Adam Tański
Keyword(s):  
Magnetic Fields ◽  
Developmental Stages ◽  
Negative Influence ◽  
Pigment Cells ◽  
Egg Activation ◽  
Industrial Equipment ◽  
Positive Effects ◽  
Early Developmental Stages ◽  
Species Specific ◽  
Early Developmental

The number of sources of anthropogenic magnetic and electromagnetic fields generated by various underwater facilities, industrial equipment, and transferring devices in aquatic environment is increasing. These have an effect on an array of fish life processes, but especially the early developmental stages. The magnitude of these effects depends on field strength and time of exposure and is species-specific. We review studies on the effect of magnetic fields on the course of embryogenesis, with special reference to survival, the size of the embryos, embryonic motor function, changes in pigment cells, respiration hatching, and directional reactions. We also describe the effect of magnetic fields on sperm motility and egg activation. Magnetic fields can exert positive effects, as in the case of the considerable extension of sperm capability of activation, or have a negative influence in the form of a disturbance in heart rate or developmental instability in inner ear organs.

scholarly journals Wnt/β-catenin Pathway-Mediated PPARδ Expression during Embryonic Development Differentiation and Disease

2021 ◽  
Vol 22 (4) ◽  
pp. 1854
Author(s):  
Tabinda Sidrat ◽  
Zia-Ur Rehman ◽  
Myeong-Don Joo ◽  
Kyeong-Lim Lee ◽  
Il-Keun Kong
Keyword(s):  
Embryonic Development ◽  
Transcriptional Activation ◽  
Target Gene ◽  
Developmental Stages ◽  
Embryonic Stem ◽  
Hereditary Diseases ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Stem Cell Regulation ◽  
Early Developmental

The Wnt/β-catenin signaling pathway plays a crucial role in early embryonic development. Wnt/β-catenin signaling is a major regulator of cell proliferation and keeps embryonic stem cells (ESCs) in the pluripotent state. Dysregulation of Wnt signaling in the early developmental stages causes several hereditary diseases that lead to embryonic abnormalities. Several other signaling molecules are directly or indirectly activated in response to Wnt/β-catenin stimulation. The crosstalk of these signaling factors either synergizes or opposes the transcriptional activation of β-catenin/Tcf4-mediated target gene expression. Recently, the crosstalk between the peroxisome proliferator-activated receptor delta (PPARδ), which belongs to the steroid superfamily, and Wnt/β-catenin signaling has been reported to take place during several aspects of embryonic development. However, numerous questions need to be answered regarding the function and regulation of PPARδ in coordination with the Wnt/β-catenin pathway. Here, we have summarized the functional activation of the PPARδ in co-ordination with the Wnt/β-catenin pathway during the regulation of several aspects of embryonic development, stem cell regulation and maintenance, as well as during the progression of several metabolic disorders.

scholarly journals Sounding out falsified medicines from genuine medicines using Broadband Acoustic Resonance Dissolution Spectroscopy (BARDS)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Anas Alfarsi ◽  
Céline Caillet ◽  
Garry Fawbert ◽  
Simon Lawrence ◽  
Jacob Krüse ◽  
...  
Keyword(s):  
Active Ingredient ◽  
Lower Cost ◽  
Principal Component ◽  
Acoustic Resonance ◽  
South East Asia ◽  
Acoustic Signatures ◽  
Falsified Medicines ◽  
Acoustic Phenomenon ◽  
The Eu

AbstractThe trade in falsified medicine has increased significantly and it is estimated that global falsified sales have reached $100 billion in 2020. The EU Falsified Medicines Directive states that falsified medicines do not only reach patients through illegal routes but also via the legal supply chain. Falsified medicines can contain harmful ingredients. They can also contain too little or too much active ingredient or no active ingredient at all. BARDS (Broadband Acoustic Resonance Dissolution Spectroscopy) harnesses an acoustic phenomenon associated with the dissolution of a sample (tablet or powder). The resulting acoustic spectrum is unique and intrinsic to the sample and can be used as an identifier or signature profile. BARDS was evaluated in this study to determine whether a product is falsified or genuine in a rapid manner and at lower cost than many existing technologies. A range of genuine and falsified medicines, including falsified antimalarial tablets from south-east Asia, were tested, and compared to their counterpart genuine products. Significant differences between genuine and falsified doses were found in their acoustic signatures as they disintegrate and dissolve. Principal component analysis was employed to differentiate between the genuine and falsified medicines. This demonstrates that the tablets and capsules included here have intrinsic acoustic signatures which could be used to screen the quality of medicines.

scholarly journals A Methodology Based on FT-IR Data Combined with Random Forest Model to Generate Spectralprints for the Characterization of High-Quality Vinegars

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1411
Author(s):  
José Luis P. Calle ◽  
Marta Ferreiro-González ◽  
Ana Ruiz-Rodríguez ◽  
Gerardo F. Barbero ◽  
José Á. Álvarez ◽  
...  
Keyword(s):  
Random Forest ◽  
Raw Materials ◽  
Principal Component ◽  
Hierarchical Cluster ◽  
Raw Material ◽  
Support Vector ◽  
Protected Designation Of Origin ◽  
Ft Ir

Sherry wine vinegar is a Spanish gourmet product under Protected Designation of Origin (PDO). Before a vinegar can be labeled as Sherry vinegar, the product must meet certain requirements as established by its PDO, which, in this case, means that it has been produced following the traditional solera and criadera ageing system. The quality of the vinegar is determined by many factors such as the raw material, the acetification process or the aging system. For this reason, mainly producers, but also consumers, would benefit from the employment of effective analytical tools that allow precisely determining the origin and quality of vinegar. In the present study, a total of 48 Sherry vinegar samples manufactured from three different starting wines (Palomino Fino, Moscatel, and Pedro Ximénez wine) were analyzed by Fourier-transform infrared (FT-IR) spectroscopy. The spectroscopic data were combined with unsupervised exploratory techniques such as hierarchical cluster analysis (HCA) and principal component analysis (PCA), as well as other nonparametric supervised techniques, namely, support vector machine (SVM) and random forest (RF), for the characterization of the samples. The HCA and PCA results present a clear grouping trend of the vinegar samples according to their raw materials. SVM in combination with leave-one-out cross-validation (LOOCV) successfully classified 100% of the samples, according to the type of wine used for their production. The RF method allowed selecting the most important variables to develop the characteristic fingerprint (“spectralprint”) of the vinegar samples according to their starting wine. Furthermore, the RF model reached 100% accuracy for both LOOCV and out-of-bag (OOB) sets.

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