scholarly journals Developmental genetic evidence for a monophyletic origin of the bilaterian brain

2001 ◽  
Vol 356 (1414) ◽  
pp. 1533-1544 ◽  
Author(s):  
Heinrich Reichert ◽  
Antonio Simeone

The widely held notion of an independent evolutionary origin of invertebrate and vertebrate brains is based on classical phylogenetic, neuroanatomical and embryological data. The interpretation of these data in favour of a polyphyletic origin of animals brains is currently being challenged by three fundamental findings that derive from comparative molecular, genetic and developmental analyses. First, modern molecular systematics indicates that none of the extant animals correspond to evolutionary intermediates between the protostomes and the deuterostomes, thus making it impossible to deduce the morphological organization of the ancestral bilaterian or its brain from living species. Second, recent molecular genetic evidence for the body axis inversion hypothesis now supports the idea that the basic body plan of vertebrates and invertebrates is similar but inverted, suggesting that the ventral nerve chord of protostome invertebrates is homologous to the dorsal nerve cord of deuterostome chordates. Third, a developmental genetic analysis of the molecular control elements involved in early embryonic brain patterning is uncovering the existence of structurally and functionally homologous genes that have comparable and interchangeable functions in key aspects of brain development in invertebrate and vertebrate model systems. All three of these findings are compatible with the hypothesis of a monophyletic origin of the bilaterian brain. Here we review these findings and consider their significance and implications for current thinking on the evolutionary origin of bilaterian brains. We also preview the impact of comparative functional genomic analyses on our understanding of brain evolution.

2008 ◽  
Vol 363 (1496) ◽  
pp. 1569-1578 ◽  
Author(s):  
Christopher J Lowe

Progress in developmental biology, phylogenomics and palaeontology over the past five years are all making major contributions to a long-enduring problem in comparative biology: the early origins of the deuterostome phyla. Recent advances in the developmental biology of hemichordates have given a unique insight into developmental similarities between this phylum and chordates. Transcriptional and signalling gene expression patterns between the two groups during the early development of the anteroposterior and dorsoventral axes reveal close similarities, despite large morphological disparity between the body plans. These genetic networks have been proposed to play conserved roles in patterning centralized nervous systems in metazoans, yet seem to play a conserved role in patterning the diffusely organized basiepithelial nerve net of the hemichordates. Developmental genetic data are providing a unique insight into early deuterostome evolution, revealing a complexity of genetic regulation previously attributed only to vertebrates. While these data allow for key insights into the development of early deuterostomes, their utility for reconstructing ancestral morphologies is less certain, and morphological, palaeontological and molecular datasets should all be considered carefully when speculating about ancestral deuterostome features.


Author(s):  
GV Chernova ◽  
PV Sidorov ◽  
NV Ergolskaya ◽  
EA Allenova ◽  
OP Endebera

Introduction: The article is devoted to the results of an experimental study of the variability of indicators of the signs of different levels of importance (population, organismal, and molecular genetic) in order to assess the impact of electromagnetic radiation of extremely high frequency (EHF EMR) as one of the physical environmental factors affecting the human body. Materials and methods: The studies were carried out on the laboratory population of Drosophila melanogaster of the wild phenotype line (D-32). The fruit flies were grown in a standard nutrient medium in special vessels at the temperature of 24.0 ± 0.1 °C in a ТС-80М thermostat subject to the necessary conditions. Results: The model genetic object revealed the effects of the factor that determined the patterns of variability of the number of individuals in the population, their body weight and the RNA content in the body depending on the dose of EHF EMR under different forms of its regulation: at the level of functional asymmetry and in the genotype-medium context. Conclusions: It was demonstrated that radiation of extremely high frequency as a factor of natural and anthropogenic origin influencing vital signs of a developing organism requires attention in a comprehensive hygienic assessment of health effects of environmental factors. This approach is necessary in view of the modifying effect of EHF EMR with respect to the viability of individuals reflecting the morphophysiological and molecular genetic state of the parent generation and its offspring.


Zootaxa ◽  
2021 ◽  
Vol 4950 (1) ◽  
pp. 181-188
Author(s):  
ROXANA TIMM ◽  
MARTIN SCHWENTNER ◽  
SIMON BOBER ◽  
ANNE-NINA LÖRZ

Intact voucher specimens are essential to allow detailed morphological observations on specimens that are used in molecular genetic studies. This can be achieved either by dissection of small, taxonomically uninformative parts of the body for DNA extraction or by employing non-destructive DNA extraction methods. The latter is particularly important for small-bodied animals. Here we test the effects of Chelex-based DNA extraction on the integrity of setae and setules in Amphipoda, fragile structures of great taxonomic importance. Our results show that DNA extraction using Chelex had no influence on the setae and setule structure and is well suited for reverse taxonomic approaches and the long-term storage of morphological vouchers. A detailed protocol for non-destructive DNA extraction is provided. 


Nature ◽  
1984 ◽  
Vol 307 (5953) ◽  
pp. 735-737 ◽  
Author(s):  
Erko Stackebrandt ◽  
Wolfgang Ludwig ◽  
Wolfgang Schubert ◽  
Friedrich Klink ◽  
Heinz Schlesner ◽  
...  

2015 ◽  
Vol 54 (03) ◽  
pp. 94-100 ◽  
Author(s):  
P. B. Musholt ◽  
T. J. Musholt

SummaryAim: Thyroid nodules > 1 cm are observed in about 12% of unselected adult employees aged 18–65 years screened by ultrasound scan (40). While intensive ultrasound screening leads to early detection of thyroid diseases, the determination of benign or malignant behaviour remains uncertain and may trigger anxieties in many patients and their physicians. A considerable number of thyroid resections are consecutively performed due to suspicion of malignancy in the detected nodes. Fine needle aspiration biopsy (FNAB) has been recommended for the assessment of thyroid nodules to facilitate detection of thyroid carcinomas but also to rule out malignancy and thereby avoid unnecessary thyroid resections. However, cytology results are dependent on experience of the respective cytologist and unfortunately inconclusive in many cases. Methods: Molecular genetic markers are already used nowadays to enhance sensitivity and specificity of FNAB cytology in some centers in Germany. The most clinically relevant molecular genetic markers as pre-operative diagnostic tools and the clinical implications for the intraoperative and postoperative management were reviewed. Results: Molecular genetic markers predominantly focus on the preoperative detection of thyroid malignancies rather than the exclusion of thyroid carcinomas. While some centers routinely assess FNABs, other centers concentrate on FNABs with cytology results of follicular neoplasia or suspicion of thyroid carcinoma. Predominantly mutations of BRAF, RET/PTC, RAS, and PAX8/PPARγ or expression of miRNAs are analyzed. However, only the detection of BRAF mutations predicts the presence of (papillary) thyroid malignancy with almost 98% probability, indicating necessity of oncologic thyroid resections irrespective of the cytology result. Other genetic alterations are associated with thyroid malignancy with varying frequency and achieve less impact on the clinical management. Conclusion: Molecular genetic analysis of FNABs is increasingly performed in Germany. Standardization, quality controls, and validation of various methods need to be implemented in the near future to be able to compare the results. With increasing knowledge about the impact of genetic alterations on the prognosis of thyroid carcinomas, recommendations have to be defined that may lead to individually optimized treatment strategies.


2018 ◽  
Vol 15 (2) ◽  
pp. 1-20
Author(s):  
Sabri Embi ◽  
Zurina Shafii

The purpose of this study is to examine the impact of Shariah governance and corporate governance (CG) on the risk management practices (RMPs) of local Islamic banks and foreign Islamic banks operating in Malaysia. The Shariah governance comprises the Shariah review (SR) and Shariah audit (SA) variables. The study also evaluates the level of RMPs, CG, SR, and SA between these two type of banks. With the aid of SPSS version 20, the items for RMPs, CG, SR, and SA were subjected to principal component analysis (PCA). From the PCA, one component or factor was extracted each for the CG, SR, and RMPs while another two factors were extracted for the SA. Primary data was collected using a self-administered survey questionnaire. The questionnaire covers four aspects ; CG, SR, SA, and RMPs. The data received from the 300 usable questionnaires were subjected to correlation and regression analyses as well as an independent t-test. The result of correlation analysis shows that all the four variables have large positive correlations with each other indicating a strong and significant relationship between them. From the regression analysis undertaken, CG, SR, and SA together explained 52.3 percent of the RMPs and CG emerged as the most influential variable that impacts the RMPs. The independent t-test carried out shows that there were significant differences in the CG and SA between the local and foreign Islamic banks. However, there were no significant differences between the two types of the bank in relation to SR and RMPs. The study has contributed to the body of knowledge and is beneficial to academicians, industry players, regulators, and other stakeholders.


2020 ◽  
pp. 15-18
Author(s):  
Inna R. Kilmetova ◽  
◽  
Igor A. Rodin ◽  
Nazira I. Khayrullina ◽  
Nikolay G. Fenchenko ◽  
...  

Summary. The disbalanced feeding and the uneven distribution of micro- and macroelements in the environment leads to a trace element, in particular hypomelanosis. To accelerate the growth and preservation of young farm animals include in the diet of various biological additives and drugs, which include selenium. For stimulation of weight gain in the livestock industry, as well as for the prevention and treatment of pathological processes in addition to micro - and macrouse amino acids, primarily methionine. The aim of this work was to study the influence of composition of DAFS-25+Polizon on morpho-biochemical parameters of blood and functional state of the liver in fattening bulls of black-motley breed in the conditions of the Republic of Bashkortostan. Experiments using were conducted on bull-calves of black-motley breed of the properties in the properties age from 6 to 15 months. The first experimental group during the experiment was additionally given the composition of DAFS-25+Polizon at a dose of 2 mg/kg, the animals of the control group received a standard diet. To assess the impact of the composition DAFS-25+Polizon on metabolism cattle studied morphological and biochemical indicators of blood and conducted histological examination of the liver. It is established that the use of the composition of DAFS-25+Polizon at a dose of 2 mg/kg increases the number of erythrocytes and hemoglobin in the experimental group and reduces the amount of white blood cells. The serum content of total protein, phosphorus and calcium increases in the group of experimental animals. Microscopic examination of the liver revealed no changes in the structure of the organ and hepatocytes in the experimental group, whereas in the control group hemodynamic disorders and dystrophic changes in liver cells were observed. Thus, the use of the composition DAFS-25+Polizon at a dose of 2 mg/kg of live weight in fattening bulls black-and-white breed contributes to the increase of redox processes in the body, stimulation of metabolism, prevent the development of liver disorders of cellular mechanisms of metabolism, optimizes the structure of the liver, which generally provides higher productivity.


2017 ◽  
pp. 132-138
Author(s):  
O.V. Paliychuk ◽  
◽  
L.Z. Polishchuk ◽  
Z.I. Rossokha ◽  
◽  
...  

The objective: determining gene polymorphism features ERS1, CYP2D6 in patients with breast cancer (RHZ) and endometrial cancer (EC) and the impact assessment studied genetic characteristics compared to receptor status (immunohistochemical determination of expression levels of ER, PR) tumors and the results of the treatment. Patients and methods. article presents the results of complex clinical, morphological, clinical-genealogical, and molecular-genetic examination of 28 females: 19 patients with breast cancer (BC), 9 patients with endometrial cancer (EC), including 5 patients with primary-multiple tumors (PMT) with and without tumor pathology aggregation in families. Results. The It was determined that in patients’ families malignant tumors of breast, uterine body and/or ovaries prevail that corresponds to Lynch type II syndrome (family cancer syndrome). Molecular-genetic examination of genomic DNA of peripheral blood and histological sections for the presence of SNPs of ESR and CYP2D6*4 genes comparing with the results of immunohistochemical study of tumors for receptors ER and PR status have not found associations between these characteristics; although among EC patients the occurrence of genotypes 397ТТ and 351АА was significantly higher comparing with BC patients (55.55% and 10.5% for genotype 397ТТ,and 15.8% for genotype 351АА, respectively). At the same time the patients with BC and primary-multiple tumors (PMT) of female reproductive system organs (FRSO) that carried mutations in BRCA1 in all the cases demonstrated positive ER and PR receptor status and adverse combinations of polymorphous variants of the genes ESR1 (397СС, 397ТС) and CYP2D6*4 (1846G, 1846GA), suggesting combined effect of these factors on the development of malignant neoplasias of FRSO in families with positive family cancer history. In BC patients, receiving standard hormone therapy with tamoxifen, those, who had genotype 1846GG of the gene CYP2D6*4, in 3 patients (15.8%) of 19 (100%) patients disease recurrence was diagnosed. Conclusion. The obtained results allow clinical use of the assessment of polymorphism frequency of the genes ESR1 and CYP2D6*4 for selection of individual hormone therapy regimens schemes for BC patients, to increase efficacy of dispensary observation after finishing of special therapy for such patients, and also personalization of complex and combined treatment regimens. Key words: breast cancer, endometrial cancer, family cancer syndrome, single nucleotide polymorphisms (SNPs) of the genes ESR1, CYP2D6*4.


Author(s):  
M. S. Bugaeva ◽  
O. I. Bondarev ◽  
N. N. Mikhailova ◽  
L. G. Gorokhova

Introduction. The impact on the body of such factors of the production environment as coal-rock dust and fluorine compounds leads to certain shift s in strict indicators of homeostasis at the system level. Maintaining the relative constancy of the internal environment of the body is provided by the functional consistency of all organs and systems, the leading of which is the liver. Organ repair plays a crucial role in restoring the structure of genetic material and maintaining normal cell viability. When this mechanism is damaged, the compensatory capabilities of the organ are disrupted, homeostasis is disrupted at the cellular and organizational levels, and the development of the main pathological processes is noted.The aim of the study is to compare the morphological mechanisms of maintaining structural homeostasis of the liver in the dynamics of the impact on the body of coal-rock dust and sodium fluoride.Materials and methods. Experimental studies were conducted on adult white male laboratory rats. Features of morphological mechanisms for maintaining structural homeostasis of the liver in the dynamics of exposure to coal-rock dust and sodium fluoride were studied on experimental models of pneumoconiosis and fluoride intoxication. For histological examination in experimental animals, liver sampling was performed after 1, 3, 6, 9, 12 weeks of the experiment.Results. The specificity of morphological changes in the liver depending on the harmful production factor was revealed. It is shown that chronic exposure to coal-rock dust and sodium fluoride is characterized by the development of similar morphological changes in the liver and its vessels from the predominance of the initial compensatory-adaptive to pronounced violations of the stromal and parenchymal components. Long-term inhalation of coal-rock dust at 1–3 weeks of seeding triggers adaptive mechanisms in the liver in the form of increased functional activity of cells, formation of double-core hepatocytes, activation of immunocompetent cells and endotheliocytes, ensuring the preservation of the parenchyma and the general morphostructure of the organ until the 12th week of the experiment. Exposure to sodium fluoride leads to early disruption of liver compensatory mechanisms and the development of dystrophic changes in the parenchyma with the formation of necrosis foci as early as the 6th week of the experiment.Conclusions. The study of mechanisms for compensating the liver structure in conditions of long-term exposure to coal-rock dust and sodium fluoride, as well as processes that indicate their failure, and the timing of their occurrence, is of theoretical and practical importance for developing recommendations for the timely prevention and correction of pathological conditions developing in employees of the aluminum and coal industry.The authors declare no conflict of interests.


Author(s):  
Elena A. Beigel ◽  
Natalya G. Kuptsova ◽  
Elena V. Katamanova ◽  
Oksana V. Ushakova ◽  
Oleg L. Lakhman

Introduction. Occupational chronic obstructive pulmonary disease (COPD) is one of the leading nosological forms of occupational respiratory disease. Numerous studies have shown high effectiveness of the combination of indacaterol/glycopyrronium (Ultibro®breezhaler®) on the impact on clinical and functional indicators in the treatment of COPD in General practice.The aim of the investigation the case of occupational COPD with the analysis of the dynamics of functional indicators, tolerance to physical load and evaluation of the quality of life of workers engaged in aluminum production by using combination of indacaterol/glycopyrronium.Materials and methods. The random sampling method included 20 men, workers of aluminum production, with the established diagnosis of professional COPD at the age of 40 to 60 years. The survey was conducted (Borg scale, medical Research Council scale (mMRC) and COPD Assessment Test (CAT). Functional methods of studies were conducted: spirometry, body plethysmography, electrocardiography (ECG) and the six-minute stepper test (6-MST).Results. Against the background of 8 weeks of therapy, the volume of forced exhalation for 1 minute (FEV1) increased by 14.7% and amounted to 67.90% of the due values, the forced vital capacity of the lungs (FVC) increased by 11.3% and amounted to 76.95% of the due. According to the body plethysmography (BPG) is set to decrease in residual lung volume on average by 13.4% and static hyperinflation, confirmed by the decrease in functional residual volume (FRV) of 18.8%. During the study period increased physical activity of patients. The average difference between the distance traveled in the six-minute step test before and after treatment was 58.8 m. The analysis of personal data showed that the quality of life of patients improved, the total score in the questionnaire CAT at the beginning of the study was 16.9 points, and after 8 weeks decreased by 63% and amounted to 10.7 points.Conclusions: The Results indicate a positive effect of combination therapy with indacaterol/glycopyrronium on the course and progression of occupational COPD.


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