Techniques used by elite long jumpers in preparation for takeoff

It was hypothesized that some characteristics of the positions adopted by long jumpers during the final strides of the approach are significantly related to the distance of the jump, and that they are so related only by virtue of their relationships with the horizontal velocity at touchdown and/or the vertical velocity at takeoff. Trials by 20 male and 26 female long jumpers were recorded cinematographically and subsequently analyzed. The takeoff distance for the fourth-last stride, the landing distance for the last stride, and the height of the center of gravity (CG) at takeoff into the jump were significantly correlated with the distance of the jump. These three position variables were significantly related to the distance of the jump, through their relationships with the velocity of the approach and the vertical velocity of the CG at takeoff into the jump. Considered alone, they were not influential in determining the distance of the jump.     

Identification of novel gangliosides containing lactosaminyl-GM1 structure from rat spleen

Two novel monosialogangliosides were isolated from rat spleen. The structures of the gangliosides (shown below, where NeuNGc is N-glycolylneuraminic acid) were characterized by compositional analysis, methylation analysis, hydrolyses with exoglycosidases, direct probe fast atom bombardment mass spectrometry, and proton nuclear magnetic resonance spectrometry. A novel structure common to both gangliosides was N-acetyllactosaminyl-GM1 LacN-GM1; where GM1 is II3NeuAc-GgOse4Cer), and this is the first paper to report the occurrence of a new group of gangliosides. [formula: see text] Furthermore, in a monosialoganglioside fraction of rat spleen, the occurrence of a ganglioside having two lactosamine units (Gal alpha 1-3(Gal beta 1-4GlcNAc beta 1-3)2-GM1(NeuAc) (alpha Gal-(LacN)2-GM1] was suggested. These gangliosides have a unique structure, which includes the ganglio series ganglioside core and the extended modification characteristic of the lacto series.     

LECTIN-LIKE COMPOUNDS AND LECTIN RECEPTORS IN MARINE MICROALGAE: HEMAGGLUTINATION AND REACTIVITY WITH PURIFIED LECTINS1

We detected lectin-like compounds and lectin receptors in microalgae by hemagglutination, competitive inhibition with sugars, and reactivity with lectins isolated from other sources. Cell extracts from eight species of Dinophyceae and from one species each of Raphidophyceae and Bacillariophyceae exhibited hemagglutination toward trypsinized rabbit erythrocytes. In addition, the culture media of the dinoflagellate Alexandrium cohorticula and the raphidophyte Chattonella antiqua displayed similar hemagglutination. These activities were not inhibited by any monosaccharides or oligosaccharides tested but were inhibited by some specific glycoproteins. This suggests that the active factors were lectin-like compounds. Upon exposing intact, healthy cells of 12 species of Dinophyceae and one species each of Raphidophyceae, Cryptophyceae, Bacillariophyceae, and Chlorophyceae to lectins isolated from either macroalgae or terrestrial plants, most species were adversely affected. The negative effects included one or more of the following: impaired motility, disappearance of motility, agglutination, abnormal morphology, and cell rupture or lysis. Some species, even after freezing, thawing, and washing with saline solution, still agglutinated with macroalgal or terrestrial plant lectins. This study suggests that lectins and carbohydrate-containing lectin receptors may commonly occur on the cell surfaces of various species of microalgae.     

Construction of an equalized cDNA library from Arabidopsis thaliana

Using a kinetic approach, a cDNA library composed of almost equal representations of all genes expressed in the aerial parts of 2-week-old Arabidopsis was constructed. A cDNA was synthesized with an oligo dT primer containing a Not l site. A linker containing the nucleotide sequence of Sse 8387I which recognizes octanucleotides was added at the ends of the synthesized cDNA. The cDNA was amplified by the polymerase chain reaction (PCR), denatured, and reassociated under modified conditions. Thereafter, the remaining single-stranded DNA was converted to double-stranded DNA and amplified by PCR. These equalization steps were repeated three times and the products were cloned unidirectionally into a plasmid vector. Equalization was evaluated by colony hybridization and DNA sequencing. This approach will be applicable to construct a cDNA library suitable for subtraction, differential screening, and expression screening, especially for mRNA species present at very low concentrations in a few cells of a specific tissue.     

Cardiovascular responses during spontaneous overground locomotion in freely moving decerebrate cats

Sadamoto, Tomoko, and Kanji Matsukawa. Cardiovascularresponses during spontaneous overground locomotion in freely movingdecerebrate cats. J. Appl. Physiol.83(5): 1454-1460, 1997.To examine whether the cerebrum isessential for producing the rapid cardiovascular adjustment at thebeginning of overground locomotion, we examined heart rate (HR), meanarterial blood pressure (MAP), and integrated electromyogram (iEMG) ofthe forelimb triceps brachialis muscle in freely moving decerebratecats during locomotion. Two to four days after decerebration surgeryperformed at the level of the precollicular-premammillary body, theanimals spontaneously produced coordinated overground locomotion,supporting body weight. HR began to increase immediately before theonset of iEMG, and MAP began to rise almost simultaneously with theiEMG onset. Their increases in HR and MAP (24 ± 3 beats/min and 22 ± 4 mmHg) were sustained during locomotion. Sinoaortic denervation(SAD) did not affect the abrupt changes in HR and MAP at the beginningof locomotion (0-4 s from the onset of iEMG), whereas SAD had acontrasting effect during the subsequent period, a decrease in the HRresponse (9 ± 1 beats/min) and an increase in the MAP response (30 ± 3 mmHg). These results suggest that the cerebrum and the rostral part of the diencephalon are not essential for producing the rapid cardiovascular adjustment at the beginning of spontaneous overground locomotion. The arterial baroreflex does not contribute to this rapidadjustment but plays an important role in regulating the cardiovascularresponses during the later period of spontaneous locomotion.

     

Relationship of lipoprotein lipase and hepatic triacylglycerol lipase activity to serum adiponectin levels in Japanese hyperlipidemic men.

OBJECTIVE: The aim of this study was to determine how lipoprotein lipase (LPL) and hepatic triacylglycerol lipase (HTGL) activity relate to serum adiponectin levels. RESEARCH DESIGN AND METHODS: Fifty-five hyperlipidemic Japanese men were recruited for this study. LPL and HTGL activity in post-heparin plasma (PHP) was measured using Triton X-100 emulsified-[14C] triolein. The remaining activity in the presence of 1M NaCl was defined as HTGL activity. Serum adiponectin levels were determined by an enzyme-linked immunosorbent assay system. RESULT: LPL activity had a positive relationship with HDL2, but had no relation with HDL3, while HTGL had positive relationship with HDL3, but had no relationship with HDL2. LPL activity showed a positive relationship [r = 0.345, p = 0.010] to serum adiponectin levels, while and HTGL activity showed an inverse relationship [r = - 0.365 p = 0.006]. Multiple regression analysis with LPL and HTGL as dependent variables and age, BMI, serum adiponectin and the homeostasis model assessment of insulin resistance (HOMA-IR) as independent variables showed LPL and HTGL's association to adiponectin did not persist after adjustments for these covariants. However, the association of LPL activity to HOMA-IR was found to persist after adjustments of age, BMI, and serum adiponectin. CONCLUSIONS: There was a co-linearity between insulin sensitivity and adiponectin as well as insulin sensitivity and LPL/HTGL activity.     

High-Mannose Specific Lectin and Its Recombinants from a Carrageenophyta <Emphasis Type="Italic">Kappaphycus alvarezii</Emphasis> Represent a Potent Anti-HIV Activity Through High-Affinity Binding to the Viral Envelope Glycoprotein gp120

We previously reported that a high-mannose binding lectin KAA-2 from the red alga Kappaphycus alvarezii, which is an economically important species and widely cultivated as a source of carrageenans, had a potent anti-influenza virus activity. In this study, the full-length sequences of two KAA isoforms, KAA-1 and KAA-2, were elucidated by a combination of peptide mapping and cDNA cloning. They consisted of four internal tandem-repeated domains, which are conserved in high-mannose specific lectins from lower organisms, including a cyanobacterium Oscillatoria agardhii and a red alga Eucheuma serra. Using an Escherichia coli expression system, an active recombinant form of KAA-1 (His-tagged rKAA-1) was successfully generated in the yield of 115 mg per a litter of culture. In a detailed oligosaccharide binding analysis by a centrifugal ultrafiltration-HPLC method with 27 pyridylaminated oligosaccharides, His-tagged rKAA-1 and rKAA-1 specifically bound to high-mannose N-glycans with an exposed α1-3 mannose in the D2 arm as the native lectin did. Predicted from oligosaccharide-binding specificity, a surface plasmon resonance analysis revealed that the recombinants exhibit strong interaction with gp120, a heavily glycosylated envelope glycoprotein of HIV with high association constants (1.48–1.61?×?10⁹ M^?1). Native KAAs and the recombinants inhibited the HIV-1 entry at IC₅₀s of low nanomolar levels (7.3–12.9 nM). Thus, the recombinant proteins would be useful as antiviral reagents targeting the viral surface glycoproteins with high-mannose N-glycans, and the cultivated alga K. alvarezii could also be a good source of not only carrageenans but also this functional lectin(s).     

The structure of M-GTFI, an inhibitor of glucosyltransferase from S. mutans, and its inhibitory relationship with other sulfate ester-containing inhibitors

M-GTFI, an inhibitor of glucosyltransferase from S. mutans was produced by Micromonospora narashinoensis strain No. 731. The isolation procedure for M-GTFI was improved and established for spectroscopic analyses, and some properties of the inhibitor were investigated. The structure of M-GTFI was shown to be trisodium [2-sulphonato-(E)-9-undecenyll-oxacyclotriacont-(E)-3- en-2-one, 16, 18-bis sulphonate. The chemical structure of M-GTFI was therefore similar to that of izumenolide which is a beta-lactamase inhibitor containing sulfate ester groups in its molecule. The inhibitory characteristics of M-GTFI were parallel to that of other inhibitory compounds containing sulphate esters but the spectrum of activity was wider.