Topochemical distribution of lignin and hydroxycinnamic acids in sugar-cane cell walls and its correlation with the enzymatic hydrolysis of polysaccharides

Background  

Lignin and hemicelluloses are the major components limiting enzyme infiltration into cell walls. Determination of the topochemical distribution of lignin and aromatics in sugar cane might provide important data on the recalcitrance of specific cells. We used cellular ultraviolet (UV) microspectrophotometry (UMSP) to topochemically detect lignin and hydroxycinnamic acids in individual fiber, vessel and parenchyma cell walls of untreated and chlorite-treated sugar cane. Internodes, presenting typical vascular bundles and sucrose-storing parenchyma cells, were divided into rind and pith fractions.     

The art of strain improvement of industrial lactic acid bacteria without the use of recombinant DNA technology

The food industry is constantly striving to develop new products to fulfil the ever changing demands of consumers and the strict requirements of regulatory agencies. For foods based on microbial fermentation, this pushes the boundaries of microbial performance and requires the constant development of new starter cultures with novel properties. Since the use of ingredients in the food industry is tightly regulated and under close scrutiny by consumers, the use of recombinant DNA technology to improve microbial performance is currently not an option. As a result, the focus for improving strains for microbial fermentation is on classical strain improvement methods. Here we review the use of these techniques to improve the functionality of lactic acid bacteria starter cultures for application in industrial-scale food production. Methods will be described for improving the bacteriophage resistance of specific strains, improving their texture forming ability, increasing their tolerance to stress and modulating both the amount and identity of acids produced during fermentation. In addition, approaches to eliminating undesirable properties will be described. Techniques include random mutagenesis, directed evolution and dominant selection schemes.     

B30.2-like domain proteins: update and new insights into a rapidly expanding family of proteins

The B30.2 domain is a conserved region of around 170 amino acids associated with several different protein domains, including the immunoglobulin folds of butyrophilin and the RING finger domain of ret finger protein. We recently reported several novel members of this family as well as previously undescribed protein families possessing the B30.2 domain. Many proteins have subsequently been found to possess this domain, including pyrin/marenostrin and the midline 1 (MID1) protein. Mutations in the B30.2 domain of pyrin/marenostrin are implicated in familial Mediterranean fever, and partial loss of the B30.2 domain of MID1 is responsible for Opitz G/BBB syndrome, characterized by developmental midline defects. In this study, we scrutinized the available sequence data bases for the identification of novel B30.2 domain proteins using highly sensitive database-searching tools. In addition, we discuss the chromosomal localization of genes in the B30.2 family, since the encoded proteins are likely to be involved in other forms of periodic fever, autoimmune, and genetic diseases.      

The lepidopteran mitochondrial control region: structure and evolution

For several species of lepidoptera, most of the approximately 350-bp mitochondrial control-region sequences were determined. Six of these species are in one genus, Jalmenus; are closely related; and are believed to have undergone recent rapid speciation. Recent speciation was supported by the observation of low interspecific sequence divergence. Thus, no useful phylogeny could be constructed for the genus. Despite a surprising conservation of control-region length, there was little conservation of primary sequences either among the three lepidopteran genera or between lepidoptera and Drosophila. Analysis of secondary structure indicated only one possible feature in common--inferred stem loops with higher-than-random folding energies-- although the positions of the structures in different species were unrelated to regions of primary sequence similarity. We suggest that the conserved, short length of control regions is related to the observed lack of heteroplasmy in lepidopteran mitochondrial genomes. In addition, determination of flanking sequences for one Jalmenus species indicated (i) only weak support for the available model of insect 12S rRNA structure and (ii) that tRNA translocation is a frequent event in the evolution of insect mitochondrial genomes.      

Effect of isolation methodology on stem cell properties and multilineage differentiation potential of human dental pulp stem cells

Dental pulp stem cells (DPSCs) are an attractive alternative mesenchymal stem cell (MSC) source because of their isolation simplicity compared with the more invasive methods associated with harvesting other MSC sources. However, the isolation method to be favored for obtaining DPSC cultures remains under discussion. This study compares the stem cell properties and multilineage differentiation potential of DPSCs obtained by the two most widely adapted isolation procedures. DPSCs were isolated either by enzymatic digestion of the pulp tissue (DPSC-EZ) or by the explant method (DPSC-OG), while keeping the culture media constant throughout all experiments and in both isolation methods. Assessment of the stem cell properties of DPSC-EZ and DPSC-OG showed no significant differences between the two groups with regard to proliferation rate and colony formation. Phenotype analysis indicated that DPSC-EZ and DPSC-OG were positive for CD29, CD44, CD90, CD105, CD117 and CD146 expression without any significant differences. The multilineage differentiation potential of both stem cell types was confirmed by using standard immuno(histo/cyto)chemical staining together with an in-depth ultrastructural analysis by means of transmission electron microscopy. Our results indicate that both DPSC-EZ and DPSC-OG could be successfully differentiated into adipogenic, chrondrogenic and osteogenic cell types, although the adipogenic differentiation of both stem cell populations was incomplete. The data suggest that both the enzymatic digestion and outgrowth method can be applied to obtain a suitable autologous DPSC resource for tissue replacement therapies of both bone and cartilage.     

Exogenous laminin induces regenerative changes in traumatized sciatic and optic nerve

Laminin is an extracellular matrix component which can promote neuritic elongation in vitro and has been implicated in the promotion of nerve regeneration in vivo. The present study was undertaken to determine if implantation of Elvax pellets containing exogenous laminin distal to site of lesion could promote regenerative responses in vivo in the adult rat peripheral (sciatic) and central (optic) nerve. In peripheral nerve preparations, Elvax pellets containing laminin or collagen were assessed for their ability to "lure" transected axons into 5-mm-long silicone tubes. In optic nerve studies, laminin pellets were inserted distal to site of nerve crush, and the extent of axonal elongation 2.5 mm to the injury site was assessed. Laminin-containing pellets appeared to support appreciable axonal elongation in both systems. This effect was dose-dependent and not exerted by collagen pellets, substrate-free pellets, or pellets containing irradiated laminin. Collagen IV had some beneficial effect in peripheral, but not central, nerve preparations.     

Ultrastructural studies of the dying-back process. V. Axonal neurofilaments accumulate at sites of 2,5-hexanedione application: Evidence for nerve fibre dysfunction in experimental hexacarbon neuropathy

Brain Cell Biology - This study examines the thesis that 2,5-hexanedione (2,5-HD) produces distal (dying-back) axonopathy by direct toxic action on nerve fibres. Single or repeated application of...     

Untersuchungen über die cytologische Bildung der ChlorogensÄure bei einigen Kompositen

Ohne Zusammenfassung     

Untersuchungen über die cytologische Bildung der Phytomelane bei einigenTagetes-Arten

Zusammenfassung Durch die Untersuchungen von Hanausek, Hartwich, Pfister, Tschirch, Gerdts und andere Forschern wurde die Aufmerksamkeit auf eine eigenartige, tiefbraune oder schwarze, kohlenstoffreiche Substanz gelenkt, die sich im Perikarp oder im Hüll-und Spreublatt vieler Kompositen findet. Dafert und Miklauz haben diese Farbstoffe Phytomelane genannt. Hanausek nimmt an. da\ die schwarze Masse aus der Mittellamelle entsteht.Unsere Beobachtungen haben eindeutig ergeben, da\ das Phytomelan nicht das Produkt einer Umwandlung der Mittellamelle ist, sondern aus kugelförmigen Körperchen entsteht, in denen sich das Phytomelan bildet. Diese besonderen Körperchen nannten wir Phytomelanoplasten.Der Ursprung dieser besonderen Körperchen blieb unbekannt.Im Jahre 1911 stellten wir fest, da\ das Stroma der Elaioplasten aus denselben Stoffen wie die Nukleolen besteht. Die Elaioplasten stehen meist in Berührung mit dem Zellkern. Au\erdem haben wir als Zyanoplasten (Anthozyanbildner) Inhaltskörper der Zellen von Blüten und Früchten zahlreicher Pflanzen beschrieben. Die Zyanoplasten liegen oft neben dem Zellkern.Diese Tatsachen führten uns zu der Annahme, da\ ein Gen oder eine Gruppe gekoppelter Gene, die in einer bestimmten Zone eines Chromosoms liegen, vom Kern aus die Anthozyanbildung auslösen. Wir nehmen nun das gleiche auch für die Bildung der Phytomelane an.     

Transitional cell carcinoma of the ovary: A rare case and review of literature

Goblet cell carcinoid of the large intestine is a rare neoplasm, usually located in ascending colon and rectum. A 60-year-old male patient underwent surgery after the diagnosis of acute abdomen. Exploratory laparotomy revealed perforation with a diameter of 1 cm at the site of the previously performed gastroenterostomy and dilatation of the right colic flexure, secondary to a solid obstructive mass located in the mid-portion of transverse colon. Histopathological investigation of the biopsies, taken from the gastroenterostomy site and the tumor, revealed mixed carcinoid-adenocarcinoma with carcinoid component, predominantly composed of goblet cells. Three cycles of FOLFOX-4 protocol was administered. Following respiratory distress secondary to pulmonary metastasis, the patient's condition deteriorated and subsequently died in the fourth postoperative month. Our aim with this paper is to point out that more cases should be reported for more effective diagnosis, histopathological study, clinical investigation, treatment and prognosis of this specific neoplasm.