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[en] In a de novo physicochemical modeling, the synthesis of biologically important sugars and other chiral compounds without any chemical initiators is demonstrated for the first time by photolysis of a concentrated formaldehyde solution and subsequent condensation of the product; chiral condensed phase detected; the splitting of enantiomers in terms of chirality sign at the moment of condensation is determined; hierarchical (three-level) helical structure of the optically active anisometric phase (strings) is detected, in which the strings of a larger diameter consists of helically plaited strings of a smaller diameter; it was found that the direction of twisting of the strings when they are helically plaited from the strings of the previous hierarchical level is determined by their supramolecular chirality (the sign of an excess of the left or right helical supramolecular submicroscopic structures); it was shown that structure formation in systems similar to prebiological may occur through the mechanism of supercoiling already in an aqueous solution of sugars with molecular weights μ of ~102 Da, that is, much earlier than linear chiral macromolecules are formed. The results are obtained under conditions that correspond to modern ideas about the form and vector of prebiological evolution, and therefore may be of fundamental importance for molecular biology.
[en] Avian mycoplasmosis is an infectious and contagious disease that mainly infects chickens and turkeys. Due to the presence of limited information on incidence of Mycoplasma gallisepticum in Faisalabad, Pakistan and the importance of the poultry industry stimulated to study very pathogenic M. gallisepticum in layer chickens in the Faisalabad area. Diagnosis of this disease in layers was done on overall history, clinical signs, post-mortem examination, serological and molecular methods. In the current study, a total of 92 samples of blood, liver, spleen, lungs, trachea and air sacs were collected from layer chicks. The serological screening was done by using the serum plate agglutination test (SPAT) and for further confirmation at the molecular level polymerase chain reaction (PCR) was performed. Out of the total, 20.65 and 15.22% samples were tested positive for M. gallisepticum by SPAT and PCR, respectively. More positive results by SPAT could be due to false-positive findings. So, PCR is regarded as a confirmed and reliable technique for the detection of the disease. This study successfully described that PCR is a more specific and reliable method for the detection of M. gallisepticum as compared to other technique like SPAT. The current study also showed that a single test or technique is not considered as a confirmatory tool for the detection of any pathogen like M. gallisepticum. (author)
[en] Radiopharmacy is a branch of nuclear medicine (NM), which was started in Sudan in 1962 at RICK (Khartoum), 1995 at NCI, Wad Medani. Later, Shendi came to the picture as a third public centre. Now there are 6 NM centres, 3 out of them are public and 3 are private. The public ones are located in Khartoum (capital of Sudan), Wad Medani (NCI is ~196 km south Khartoum) and Shendi (~200km north Khartoum). There are two more centres are coming up, one in Marawe (north Sudan) and the other is in Alobaid (west Sudan). Instruments available, functions and size: all the centres are equipped with SPECT gamma cameras, dose calibrators. The functions and size of radiopharmacy units in Sudan are different from one to another. In RICK, there are an oncology department, NM department, and medical laboratories for general investigations. In NCI there are 6 departments on oncology, NM, radiology, medical physics, laboratories and blood bank, and molecular biology. In Shendi there are oncology and NM departments.
[en] After the end of human genome project, the cost of genetic analysis has rapidly declined with the advancement of next-generation sequencers. In addition, the relationship between various diseases and genes has been clarified. Therefore, it is likely that genetic testing may be performed in daily clinical practice in the near future. In such background, a novel research 'radiomics' is spreading to offer a new viewpoint for the use of genotype in radiological field which has traditionally focused on the analysis of imaging phenotypes. Radiomics is applied to the molecular classification or treatment strategy. This paper explains what radiomics is and what kind of changes it would bring. (author)
[en] A group of 14 patients suspected of having a hereditary myotonic condition is investigated for clinical classification. Genetic variants in the Chloride Voltage-Gated Channel 1 (CLCN1) and Sodium Voltage-gated Channel Alpha Subunit 4 (SCN4A) genes responsible for the disease were analyzed. The screening of the genes was carried out mainly by means of Polymerase Chain Reaction (PCR), Single-Stranded Conformation Polymorphism (SSCP) and automatic sequencing. Bioinformatics tools determined the conservation and possible functional effects of the genetic variants. The mutations responsible for channelopathies in some patients were determined to be non-existent; however, the exons of the sodium and chloride channels were sequenced, ruling out the presence of mutations in these genes
[es]Un grupo de 14 pacientes con sospecha de padecer una condicion miotonica hereditaria es investigado para su clasificacion clinica. Variantes geneticas en los Canal 1 de Voltaje de Cloruro (CLCN1) y Subunidad Alfa 4 de Canal Regulado por Voltaje de Sodio (SCN4A) responsables de la enfermedad fueron analizadas. El tamizaje de los genes fue realizado principalmente por medio de Reaccion en Cadena de la Polimerasa (PCR), Polimorfismo de Conformacion de Cadena Simple (SSCP) y la secuenciacion automatica. Herramientas bioinformaticas determinaron la conservacion y posibles efectos funcionales de las variantes geneticas. Las mutaciones responsables de las canalopatias en algunos pacientes fueron determinadas inexistentes; sin embargo, los exones de los canales de sodio y cloruro fueron secuenciados, descartando la presencia de mutaciones en estos genes
[en] The human growth hormone deficiency (GHD) is the most common deficiency related to pituitary hormones. The current therapy is based on daily injections of recombinant human growth hormone (r-hGH). This therapy, however, presents some disadvantages, as the need for frequent injections of r-hGH during a long life time, depending on the deficiency severity and the high cost of this hormone, due to the expensive purification processes. An alternative to the standard treatment should be to avoid these inconveniences via a sustainable hormone release, acting for a long time and providing normal and sustainable levels of insulin-like growth factor-I (IGF-I). A possible alternative is in vivo gene therapy, based on the administration of plasmid DNA in several organs/tissues, followed by electroporation. This methodology is considered very promising and has been the target of many different studies for several types of systemic deficiencies. In the present work several administrations of a plasmid containing the human growth hormone gene were carried out, in the exposed quadriceps or non-exposed tibialis cranialis muscle, followed by electroporation, using immunodeficient dwarf mice 40-80 days old. The goal was to obtain a phenotypic correction of dwarfism, through the evaluation of different growth parameters. The administration of this plasmid, in the tibialis cranialis muscle of 40 day old mice, was able to provide a normalization of mIGF-I levels, when compared to non GHD mice. Furthermore, catch-up increases of longitudinal growth parameters of 36-77% were obtained. Aiming a high efficiency on GH expression, parental plasmids were constructed and from these DNA minicircles were generated with CMV and Ubiquitin C promoter and hGH or mGH cDNA sequences. These DNA minicircles were transfected into HEK 293 cells and were even 2 times moren efficient than conventional plasmids with CMV promoter. This data are very promising and pave the way for more efficient assays utilizing this type of gene therapy protocol for GHD, aiming at a normalization of all growth parameters. (author)
[en] In this review, we show improvements to the semiempirical quantum chemical method RM1 and present a wide range of its applications as reported by researchers of various areas, such as theoretical, organic, physical, analytical, and inorganic chemistry, as well as their interfaces with medicinal chemistry, biology, and materials science. Success of RM1 is seemingly due to its ability to predict structural, energetic, electronic and wave function dependent properties of the investigated systems, coupled with its low computational demand required to perform calculations when compared to ab initio and density functional methods. Moreover, RM1 is widely available in several computational chemistry software, such as MOPAC, GAMESS, Amber, Spartan, HyperChem, and AMPAC. This review describes various case studies that perhaps can be of interest to researchers who might need a more solid basis from which to expand the frontier of applicability of RM1 to even more complex problems on larger systems. (author)
[en] In this research thesis, the author essentially tried to determine whether irradiated starch is toxic for a micro-organism, and which are the most dangerous radio-formed molecules and at which level these molecules act. For this purpose, he undertook a systematic analysis of the phenomenon by listing the different parameters for which growth anomalies had been recorded. Then, he assumed and confirmed that hydrogen peroxide was the main toxic compound. Thus, after a detailed bibliographical study which addressed several topics (prokaryotes, unicellular eucaryotes, tissue culture, and drosophila, rats, mice and men as exposed subjects), and a presentation of materials and methods (micro-organisms, culture environment, starch, irradiation, extraction of radiolysis products), the author reports and analyses experimental results related to the action mode of extracts of irradiated starch on micro-organism growth (influence of irradiation conditions, of starch characteristics and post-irradiation treatments, of micro-organism type, germ number and culture environment), discusses the role of oxygenated water and of organic peroxides, and reports the analysis of the action mode of hydrogen peroxide and extracts of irradiated starch on the Escherichia coli bacteria.
[fr]L'evaluation toxicologique represente une demarche essentielle dans toute recherche sur l'irradiation des denrees. Elle est abordee au Service de RadioAgronomie sur l'exemple de l'amidon de mais par des essais sur rats et souris et par des cultures bacteriennes effectuees a partir d'extraits du polysaccharide irradie. Ce second volet de l'etude, rapporte ici, a ete entrepris en raison de la facilite de manipulation d'un micro-organisme et de la rapidite des resultats acquis sur plusieurs generations. Apres avoir mis au point les techniques capables de mesurer les phases de latence ou la letalite d'Escherichia coli cultivee en presence de produits de radiolyse, nous avons pu, dans un premier temps, determiner avec assez de precision les conditions pour lesquelles la toxicite des extraits d'amidon irradie etait maximale ou minimale donc de maitriser tous les parametres influencant les resultats. Cette premiere partie a aussi permis de degager, parmi les differents composes radiolytiques doses au laboratoire, le peroxyde d'hydrogene comme principal produit toxique. Nous avons verifie l'hypothese de l'activite bactericide de l'eau oxygenee ou de ses proches homologues superieurs par differentes techniques. Il faut toutefois souligner que le principal compose toxique n'est pas directement issu de la chaine carbonee de l'amidon mais provient de la radiolyse de l'eau et de l'action de l'oxygene dissous ou de la coupure homolytique de cette eau par les radicaux libres radioformes. Il semble cependant possible que le peroxyde d'hydrogene forme avec d'autres molecules radiolytiques des peroxydes organiques carbonyles du type radioalkylperoxydes (ROOR) ou radioalkylhydroperoxydes (ROOH). Enfin, et comme il faut s'y attendre de la part d'un oxydant aussi energique que l'eau oxygenee, plusieurs sites intracellulaires peuvent etre affectes par ce compose. Si l'ADN parait relativement peu modifie - pas d'induction de phages, pas de mutations - d'autres molecules du type des acides α-cetoniques intervenant dans le metabolisme bacterien sont completement degradees. Il en est de meme pour certains groupements thiols qui, oxydes en pont disulfure, deviennent incapables d'assurer les cycles d'oxydoreduction necessaires au metabolisme. A ce titre, un lieu d'action privilegie de l'eau oxygenee est constitue par l'ensemble glycolyse-cycle de Krebs qui se trouve bloque non seulement par oxydation irreversible de l'acide lipoique mais aussi par decarboxylation oxydative des deux principaux intermediaires: les acides pyruvique et α-cetoglutarique. Nous rappelons ici que cette voie metabolique etant en quelque sorte le noeud vital du metabolisme bacterien tant au point de vue formation d'energie (ATP a partir du NADH2 produit) qu'au point de vue synthese des acides amines et de certains acides nucleiques, toute perturbation peut entrainer un arret total de la vie cellulaire. Le peroxyde d'hydrogene, principal produit de radiolyse toxique de l'amidon, possede donc une reactivite multisite, c'est-a-dire qu'il bloque le metabolisme cellulaire en de nombreux points vitaux dont les plus importants sont le cycle des acides tricarboxyliques et la glycolyse. Toutefois, avant d'utiliser ces resultats pour d'autres organismes plus complexes, il est necessaire de se rappeler que les bacteries sont des cellules baignant dans un milieu toxique et ne possedant pas toutes les etapes de detoxication que l'on trouve chez des etres plus evolues. L'extrapolation globale de ces resultats aux organismes superieurs est d'autant plus problematique qu'il arrive parfois qu'au contraire ces derniers transforment en substance toxique des produits sans action sur les bacteries. Les resultats que nous avons presentes ici peuvent cependant servir a orienter les futures recherches dans ce domaine. (auteur)
[en] Full text: Small Angle X-Ray Scattering (SAXS) is a popular and well established experimental technique with an extensive range of applications. Such fact arises from its flexible sample preparation, allowing researchers to study proteins in the most diverse environments and experimental conditions. SAXS is of special interest to protein studies, and hybrid data analysis methods with inputs from other techniques, such as NMR spectroscopy and X-Ray crystallography, yield complimentary results, allowing better understanding of protein structure and dynamics in solution. In recent years, new SAXS data analysis methods for proteins are emerging with new ways to address model validation, structural parameters calculation and integration with databases. Some of these tools do not require an user input, allowing one to obtain immediately relevant information on the protein conformation in a way that it could be implemented for automated data analysis pipelines in beamlines. The aim of this study is to highlight recent advances in this field and illustrate its applicability and performance to data obtained in the SAXS1 beamline at LNLS. To do so, we measured chaperone proteins related to the Hsp70 and Hsp90 families, which are of special biological relevance due to its role in protein misfolding and aggregation issue. We have shown that the use of these new tools for SAXS data analysis can, undoubtedly, improve our understanding on molecular chaperone structure and dynamics. (author)
[en] Liver is the key organ (detoxifier) that gets injured by reactive oxygen species (R O S) which deplete the body’s stores of anti-oxidants. R O S is present in all chronic liver diseases leading to oxidative stress. Consumption of foods high in anti-oxidants replenishes and supplies the body with important anti-oxidants which break down R O S lowering inflammatory responses and preventing liver damage. In this work, ginger, thyme, cinnamon, clove and honey, which are known to be rich in anti-oxidants extracts were evaluated for their potential to breakdown R O S and lower oxidative stress in rats. Purified extracts were tested in vitro for R O S scavenging by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and in vivo using CCl4-induced liver injury model. A total of 90 experimental rats were assigned to 9 groups each consisting of 10 animals and treated as follows; 1. CCl4 group: fed on CCl4 in olive oil 2. honey group: fed CCl4 then honey extract, 3. clove group: CCl4 then clove extract, 4. untreated control group: rats fed on standard diet and 5. Negative control: fed olive oil, 6. ginger group: fed CCl4 then ginger extract, 7. cinnamon group: fed CCl4 then cinnamon extract, 8. Mix group: fed CCl4 then mixture of clove, cinnamon and ginger extracts and 9. thyme group: fed CCl4 then thyme extract. At 10 weeks, liver histopathology was done and sera collected for liver and kidney function tests. CCl4 -only treated rats showed fibroblastic cells proliferation and inflammatory cells infiltration which was absent in the control animals. Cinnamon and clove extract did not exhibit fibroblastic cells proliferation at all. All extracts significantly reduced cytokines (T G F-β, TNF-α and EGF) and liver function enzymes’(A L T, A S T and G G T) activity in serum compared to the CCl4 group. Clove highly inhibited DPPH (77.2%) compared to honey (6.5%) and conferred better liver protection against CCl4. There were insignificant changes in the levels of testosterone among experimental groups. While significant decrease of insulin was recorded in the CCl4 group compared to untreated and negative controls. All extracts significantly reduced the gene expression of the cytokines T G F-β and TNF-α in liver. These findings indicate that clove and cinnamon contain compounds that have anti-oxidant activity with the ability to reverse liver fibrosis. Frequent consumption of these foods may lower liver damage and prevent development of some liver diseases. Public health education on nutritional benefits of these foods is strongly encouraged