Production of a specific antibody against pyruvate kinase type M2 using a synthetic peptide

The pyruvate kinase isozymes M1 and M2 are structurally and immunologically closely related. To obtain an antibody which discriminates between these two forms, a synthetic tetradecapeptide with a sequence specific for pyruvate kinase type M2 from rats was constructed. Antisera from rabbits, immunized with this peptide, reacted specifically with the M2-type holoenzyme of both rat and human origin, and did not cross-react with the M1-type isozyme. This was established by immunoblot analysis, both under dissociating and non-dissociating conditions.     

Proposal for adoption of the base of the Undulograptus austrodentatus Biozone as a global Ordovician stage and series boundary level

The base of the Undulograptus austrodentatus Biozone appears to be a synchronous event that is widely recognizable within graptolitic facies around the world. It occurs within an interval in which graptolite species ranges are now well known and in which there is a rapid turnover in the composition of graptolite faunas. This turnover reflects the rapid evolutionary radiation of the Diplograptacea simultaneously with the appearance of several distinctive pseudisograptid and glossograptid species. These events provide the basis for the recognition of two thin but widely applicable subzones; a lower Arienigraptus zhejiangensis Subzone and an upper U. sinicus Subzone. The occurrence of the lower boundary of the U. austrodentatus Biozone within a succession of first appearances also permits accurate and reliable identification of the boundary as well as assessment of stratigraphic completeness across the boundary interval in correlated sections. Diverse graptolite faunas of late Yapeenian and early Darriwilian age occur in association with the Histiodella altifrons Biozone of the North American midcontinent conodont zonation and the Paroistodus originalis and Microzarkodina parva biozones of the North Atlantic conodont zonation. They also occur in association with the shelly-fossil zonations developed for several different continents. These features of the base of the U. austrodentatus Biozone make it a suitable level for use as the boundary level for a global stage. Its stratigraphic position within the Ordovician System relative to other likely global stages as well as its coincidence with one of the major events in graptolite evolutionary history suggest that this level also may be a suitable level for the base of a global Middle Ordovician Series.Ordovician System, Ordovician stages, graptolite zonation, chronostratigraphy, international correlation. Charles E. Mitchell and Jörg Maletz, Department of Geology, State University of New York at Buffalo, Buffalo, New York 14260-1550, USA; 13th July, 1994; revised 22nd May, 1995.     

Heterogeneity of Intermediate Filament Expression in Vascular Smooth Muscle: A Gradient in Desmin Positive Cells from the Rat Aortic Arch to the Level of the Arteria Iliaca Communis

The display of the two distinct intermediate filament proteins, desmin and vimentin, in rat vascular smooth muscle tissue was studied by immunofluorescence microscopy on frozen sections of aorta and other blood vessels. Vascular smooth muscle cells present in these vessels always appeared rich in vimentin. However, staining of sections covering six distinct but contiguous parts of the aorta showed that the number of desmin containing cells was low distal to the truncus brachiocephalicus, but increases until in distal parts of the aorta and in the arteria iliaca communis almost all cells appear positive for desmin. Thus blood vessels show heterogeneity of intermediate filament expression not only in cross-section but can also display heterogeneity along their length. Muscular arteries such as the renal artery and the arteria femoralis, as well as arterioles and veins including the vena jugularis and the vena cava also contain desmin. Thus it may be that low numbers of desmin-positive cells are typical of elastic arteries, while muscular arteries and other blood vessels are characterized by large numbers of desmin-positive cells. We discuss whether desmin-positive and desmin-negative vascular smooth muscle cells may perform different functions and raise the possibility that desmin expression may coincide with the turn on of a specially regulated contractility program.     

A new variant of glucosephosphate isomerase deficiency.

A new variant of glucose-6-phosphate isomerase deficiency is described. The enzyme kinetics and properties were studied. Genetic and electrophoretic data pointed to a double heterozygous state in the patient. These data are compared to the other variants described in the literature until now.     

Insect juvenile hormone mimics: A structural basis for gonadotropic activity in a cockroach and a moth

Exogenously applied natural juvenile hormones (JH) and some synthetic JH mimetic substances resulted in dose-related gonadotropic responses and were able to fully substitute for the absence of endogenous JH in a moth and a cockroach. Aliphatic methyl and ethyl esters, thio esters, and amides were most active. Some aromatic JH mimics with high activity in morphogenetic assays on a variety of insects showed little activity in the gonadotropic bioassay. This suggests that the ovaries of the moth Manduca sexta and the cockroach Nauphoeta cinerea respond primarily to the intrinsic JH activity of the test substances.     

New Natural Noncannabinoid Ligands for Cannabinoid Type-2 (CB2) Receptors

Since the discovery that Δ ⁹-tetrahydrocannabinol and related cannabinoids from Cannabis sativa L. act on specific physiological receptors in the human body and the subsequent elucidation of the mammalian endogenous cannabinoid system, no other natural product class has been reported to mimic the effects of cannabinoids. We recently found that N-alkyl amides from purple coneflower (Echinacea spp.) constitute a new class of cannabinomimetics, which specifically engage and activate the cannabinoid type-2 (CB₂) receptors. Cannabinoid type-1 (CB₁) and CB₂ receptors belong to the family of G protein-coupled receptors and are the primary targets of the endogenous cannabinoids N-arachidonoyl ethanolamine and 2-arachidonoyl glyerol. CB₂ receptors are believed to play an important role in distinct pathophysiological processes, including metabolic dysregulation, inflammation, pain, and bone loss. CB₂ receptors have, therefore, become of interest as new targets in drug discovery. This review focuses on N-alkyl amide secondary metabolites from plants and underscores that this group of compounds may provide novel lead structures for the development of CB₂-directed drugs.     

Electrical neuromodulation for patients with cardiac diseases

In this review we discuss the position of electrical neuromodulation as a safe and reversible adjuvant therapy for treatment of patients with chronic cardiac diseases who have become refractory to conventional strategies. In patients with chronic refractory angina, electrical neuromodulation, independent of the applied modality, has shown to reduce complaints of angina, to enhance exercise capacity, to improve quality of life and to employ anti-ischaemic effects. To date, electrical neuromodulation seems to be one of the best adjuvant therapies for these patients. In addition, neuromodulation in the treatment of heart failure and resistant arrhythmias is the subject of several ongoing studies.