Doppler ultrasonography was used to examine 198 neck-vein systems (67 right, 131 left) in 148 patients. The vessel lumen is usually echo-free: the veins are supple, and the internal jugular and sometimes the subclavian veins can be compressed. The venous confluence is Y-shaped. Blood flow was symmetrical and biphasic in 57% of cases, continuous in 29% of cases, and monophasic in 13% of cases. Blood flow velocity was less than 1 m/s in all cases and varied with respiration and heart rate. Color Doppler allows flow imaging and increases the speed and reliability of the procedure. This investigation is useful for following-up patients with indwelling venous catheters and is the investigation of choice whenever pathology of the neck veins is suspected.

Adolescent↗

PubMedDate not supplied

The size of the myofibers in mature grafts of the mouse extensor digitorum longus muscle.

The histochemical profile of stabilized orthotopically grafted mouse extensor digitorum longus muscles (EDL) and fiber type diameter distribution in the graft was compared with control muscles. Histochemical fiber typing, based on myofibrillar ATPase reactions, indicated that type 1 fiber accounted for less than 1%, type 2a fibers for 30%, and type 2b fibers for 69% of the total fiber population of the graft. In control muscles of 56-day-old and 156-day-old mice, type 1 fibers accounted for less than 1%, type 2a fibers for 36%, and type 2b fibers for 63% of the total fiber population of normal muscles. The regenerating myofibers in stabilized grafts failed to achieve the normal fiber diameter. The type 2b fibers exhibited greater growth inhibition than did type 2a fibers.

Animals↗

PubMedDate not supplied

Abzyme generation using an anti-idiotypic antibody as the "internal image" of an enzyme active site.

Since the two reports published in 1986 by the laboratories of R. Lerner and P. G. Schultz, it has been clearly established that antibodies may be induced to act as catalysts in numerous chemical reactions. In all cases, catalytic antibodies were elicited using a substrate-based approach. In the present article, we propose an alternative and complementary enzyme-based approach to generate catalytic antibodies. This approach uses the properties of anti-idiotypic antibodies to generate internal images of enzyme active sites. Experimental results are discussed for polyclonal and monoclonal anti-idiotypic antibodies.

Acetylcholinesterase↗

PubMedDate not supplied

Trends in alcohol consumption in undergraduate third level students: 1992-1999.

BACKGROUND: Alcohol consumption has increased in the Irish population in recent years. It is not known to what extent the student population has been affected by this increase. AIM: To determine levels of alcohol consumption among undergraduates in one Irish university and identify changes in drinking patterns in the years 1992-1999. METHODS: Information on alcohol use was obtained by anonymous self-completed questionnaire in a stratified random cross-faculty sample of undergraduates in 1992 and 1999. The CAGE questionnaire to determine problem drinking was included in both surveys. RESULTS: A statistically significant (p=0.01) drop in weekly alcohol consumption by males was found, although the proportion of male problem drinkers increased. Consumption for females remained the same. CONCLUSIONS: Findings are contrary to recent figures for drinking patterns in young Irish people in general. The fall in alcohol consumption in male students may be linked to improved male insight into the negative effects of alcohol or to the substitution of cheaper available substances.

Adult↗

PubMedDate not supplied

Interaction of spirochetes with the host.

The success of an invading organism must depend on several cytoplasmic, surface-associated and secreted factors. The technical difficulties in handling pathogenic spirochetes like Treponema pallidum and Borrelia burgdorferi have made it difficult to define specific factors involved in entry and long-term survival. The problem of defining virulence factors has been attacked by several strategies: T. pallidum secretes a number of immunogenic low molecular mass proteins. The most predominant are of molecular weight 15.5 and 22 kDa. Preliminary data suggest that antibodies against these proteins induce protective immunity in rabbits experimentally infected with T. pallidum. Many potentially important surface-associated antigens of T. pallidum have now been cloned and characterized. Two of these, TpD and TpE, are lipoproteins which exhibit characteristic size heterogeneity. The apparent molecular weight of TpE from T. pallidum and T. pertenue are different. The clinical symptoms in syphilis and yaws are very different, but sequence analysis of TpE has shown that the TpE proteins are indeed very similar in the two strains. This observation makes it unlikely that heterogeneity of TpE can account for the different clinical symptoms of syphilis and yaws. Sequence data for another newly sequenced surface-associated antigen of T. pallidum (molecular weight 41 kDa) indicate that this protein is involved in glucose transport and chemotaxis/motility. Intracellular factors like the molecular chaperonin GroEL have been documented both in treponemes and borreliae. This stress protein is involved in cellular repair processes and folding/assembly of protein subunits. Indirect evidence suggests that GroEL affects the ability of spirochetes to survive in the stressful environment of the infected host. Several lines of evidence suggest that the Osp proteins of Borrelia are important for host/parasite interaction. Further support for this idea has come from studies of a series of monoclonal antibodies against OspA. A monoclonal antibody against OspA (9B3D) is able to block attachment of B. burgdorferi to a cell monolayer. Borrelia loses infectivity after several passages in vitro. The loss of pathogenicity is associated with loss of specific plasmids and proteins. One of the low-passage-associated proteins (Lap30) has been cloned and sequenced. Lap30 is a lipoprotein encoded by a 38-kb plasmid, not present in high passage B. burgdorferi. Aberrant immunological processes induced by the lipopolysaccharide component of Treponema hyodysenteriae could explain the dramatic intestinal lesions in swine dysenteriae. But analysis by TLC reveals that the LPS of this treponeme is different from classical Salmonella LPS.(ABSTRACT TRUNCATED AT 400 WORDS)

Bacterial Outer Membrane Proteins↗

PubMedDate not supplied

Metabolic disposition of pyrithiones.

The urinary pattern of pyrithione metabolites in urine of the rat, rabbit and rhesus monkey was similar to that of the swine after iv. administration of sodium pyrithione (Sodium Omadine) and the magnesium sulfate adduct of 2,2'-dithio-bis(pyridine-1-oxide), (Omadine MDS). The major metabolite accounting for 80% or more of the metabolites in urine was the S-glucuronide of 2-mercaptopyridine-N-oxide. After Omadine MDS administration, three transient metabolites and one persistent metabolite were observed in the plasma. The transient metabolites were tentatively identified as 2-methylthiopyridine-N-oxide, 2-methylsulfinylpyridine and 2-methylsulfinylpyridine-N-oxide. 2-Methylsulfonylpyridine was the only metabolite observed in the plasma 16 hr after Omadine administration. This metabolite could be detected 14 days after rats were treated repeatedly with a shampoo formulation containing Omadine MDS.

Administration, Topical↗

PubMedDate not supplied

Comparison of the amino acid compositions and antigenic properties of spiralins purified from the plasma membranes of different spiroplasmas.

Spiralins were purified by agarose-suspension electrophoresis after extraction with detergents from the membranes of the following spiroplasmas: Spiroplasma citri C189, S. citri Maroc (R8A2), S. citri Scaph and the honey-bee spiroplasma B88. The four proteins (molecular mass congruent to 26,000 daltons, as determined by sodium dodecyl sulphate-pore gradient electrophoresis) showed very similar amino acid compositions characterized by the absence of methionine and tryptophan and a high polarity index (greater than 49%). When compared with the amino acid composition of S. citri membrane, the four spiralins had little or no histidine, a low content of glycine, leucine, tyrosine, phenylalanine and arginine, and a high content of threonine, alanine and valine. Comparison of the amino acid compositions according to the criteria described by Cornish-Bowden (Anal. Biochem., 1980, 105, 233-238) strongly suggests that all four spiralins are related. A crossed immunoelectrophoretical comparison, however, shows that though the three proteins purified from S. citri strains (serogroup I-1) are antigenically similar, they do not seem to share common epitopes with spiralin from the honey-bee spiroplasma B88 (serogroup I-2).

Amino Acids↗

PubMedDate not supplied

Postoperative management of extensor tendon repairs in zones V, VI, and VII.

This paper describes the postoperative management plan for extensor tendon repair in zones V, VI, and VII as conceived by the Grenoble team. This plan includes immediate, postoperative systematic mobilization for all patients with surgical repairs in zones II through VIII. Postoperative mobilization in zones V and VI is performed under the protection of a Levame-type, dorsal steel leaf-blade spring. Depending on lesion location, proximal or distal to juncturae tendinum, Frère's three-finger rule applies. In zone VII, differential tendon gliding between the wrist and finger extensors and surrounding tissue is accomplished with a Tom splint, which gives individual extension assistance to each digit and the wrist while limiting flexion.

Biomechanical Phenomena↗

PubMedDate not supplied

High resolution MR technique in the diagnosis of mesial temporal sclerosis. Correlative MRI and pathological features.

Mesial temporal sclerosis, otherwise known as hippocampal sclerosis, is the most common entity associated with medically intractable temporal lobe epilepsy. The neuronal loss and gliosis of the hippocampus that is pathologically characteristic of this disorder is thought to serve as an epileptogenic substrate. Accurate identification and localization of this pathology is crucial before surgery is considered to potentially cure medically intractable seizures. Magnetic resonance imaging plays a central role in the presurgical work-up. We present a 44-year-old man with a history of intractable partial complex seizures secondary to right-sided mesial temporal sclerosis and discuss the magnetic resonance imaging findings utilizing a high resolution technique.

Adult↗

PubMedDate not supplied

Catalysis of esterolytic reactions by the anti-idiotypic antibody against human erythrocyte acetylcholinesterase.

Explore the source record for details and available documents.

Acetylcholinesterase↗

PubMedDate not supplied

[A structure-activity study of a catalytic antiidiotypic antibody to the human erythrocyte acetylcholinesterase].

The catalytic monoclonal antibody 9A8 (MA 9A8), antiidiotypic to the antibody AE-2 (MA AE2) produced to the active site of acetyl cholinesterase from human erythrocytes, was subjected to a structure-function study. The specific binding of MA 9A8 to MA AE2 (K 2.26 x 10(9) M-1) was shown by the method of surface plasmon resonance, and the functional activity of MA 9A8 was demonstrated. Unlike acetyl cholinesterase, this antibody specifically reacted with the irreversible phosphonate inhibitors of esterases. A peptide map of MA 9A8 was analyzed by MALDI mass spectrometry. The Ser99 residue of its heavy chain was shown to be within the active site of the catalytic antibody. A computer modeling of the MA 9A8 active site suggested the existence of a catalytic dyad formed by Ser99 and His35. A comparison of the tertiary structures of the MA 9A8 and the 17E8 monoclonal antibody, which also exhibited an esterase activity and was produced to the stable analogue of the reaction transition state, indicated a practically complete coincidence of the structures of their presumed active sites.

Acetylcholinesterase↗

PubMedDate not supplied

Atrial natriuretic peptide inhibits angiotensin-stimulated proximal tubular sodium and water reabsorption.

The discovery that atrial extracts have potent diuretic and natriuretic properties revealed a possible endocrine function of the heart in the regulation of extracellular fluid volume. Since that first report intense research activity has been directed towards determining the mechanism of action of the active atrial natriuretic polypeptides (ANP) found in these extracts. Despite these efforts it remains controversial whether the renal actions of ANP are exerted solely on the process of glomerular filtration or involve additional direct actions on tubular transport. We have investigated the possibility that atrial natriuretic polypeptides may induce natriuresis by suppression of proximal tubular sodium and water reabsorption. Using shrinking split-drop micropuncture combined with simultaneous capillary perfusion in anaesthetized rats we report that 20 nanomolar alpha-rANP (the main component of ANP in rat plasma) added to the peritubular fluid had no direct effect on proximal fluid uptake whereas picomolar angiotensin II had a marked stimulatory action as reported. The stimulatory effect of angiotensin II on fluid reabsorption was inhibited by peritubular ANP at physiological concentrations and abolished by higher concentrations of ANP. Thus at physiological concentrations ANP acts within the kidney to decrease proximal reabsorption by inhibition of angiotensin-stimulated sodium and water transport.

Angiotensin II↗

PubMedDate not supplied

Effects of resistance training on bone parameters in young and mature rats.

1. Osteoporosis is a major public health problem that is predicted to worsen over the next decade and preventative strategies that increase bone strength have become the focus of substantial research. 2. Although mechanical load is a primary factor in the acquisition and maintenance of skeletal tissue, the type of exercise used and when in life it is most effectively prescribed remain inconclusive. 3. The present study compared 10 weeks of resistance training in both young and mature female Sprague-Dawley rats and measured bone density and body composition by dual energy X-ray absorptiometry and biomechanical properties by three point bending tests of the tibia and femur. 4. No significant differences were observed for any of the bone parameters when comparing exercise and control groups at either age. This was despite using a comparable training protocol to that in humans and using loads of approximately 150% bodyweight. 5. The present study concludes that more intensive work programmes of resistance training or different outcome measures are required when using animal models for skeletal research.

Age Factors↗