Portal hypotensive effects of DL-028 and prazosin on portal hypertensive rats

The portal hypotensive effects of prazosin and DL-028 (chem- ical name: 3-[[4-(2-methoxyphenyl)piperazin-1-yl]methyl]- 2, 3-dihydroimidazo[1,2-c]quinazolin-5(6H)-one(27b)), a synthetic alpha1-adrenoceptor antagonist, were assessed in portal hypertensive rats. Portal hypertension was induced by partial portal vein ligation in Sprague-Dawley rats. Two weeks after ligation, when the hyperdynamic state was stabilized the rats were anesthetized after an overnight fast and cannulated for measuring mean arterial pressure (MAP), portal venous pressure (PVP), cardiac index (CI) and heart rate (HR). Both DL-028 and prazosin (1, 3.3 and 10 microgram/kg) induced dose-dependent decreases of PVP and MAP after intravenous infusion, with effects lasting for longer than 30 min. The maximum percentage reduction of PVP after DL-028 was 10, 10 and 15%, respectively, for the dosages given (1, 3.3 and 10 microgram/kg), and 5, 12 and 25%, respectively, after prazosin. CI was not changed by either drug. HR was not changed by either drug except DL-028 at 10.0 microgram/kg with a bradycardiac effect. Our results showed that both DL-028 and prazosin reduced PVP in portal hypertensive rats.     

CHEB, a convulsant barbiturate, evokes calcium-dependent spontaneous glutamate release from rat cerebrocortical synaptosomes

CHEB [5-(2-cyclohexylidene-ethyl)-5-ethyl barbituric acid] is a potent convulsant barbiturate that causes direct neuronal excitation by an unknown mechanism. We have analyzed the effects of CHEB on the release of endogenous glutamate from rat cerebrocortical synaptosomes using an on-line enzyme-coupled fluorimetric assay. CHEB evoked spontaneous Ca(2+)-dependent glutamate release with an EC50 = 14.2 microM and an Emax = 3.2 mumol/min/mg. The non-convulsant barbiturates pentobarbital and phenobarbital evoked significantly less glutamate release at high concentrations. CHEB (30 microM) increased intrasynaptosomal [Ca2+] by 58 +/- 4 nM (p < 0.01; n = 4) above baseline compared to an increase of 5 +/- 4 nM (NS; n = 4) produced by pentobarbital (30 microM). CHEB-evoked glutamate release was inhibited by pentobarbital, phenobarbital, EGTA, CoCl2/CdCl2 and flunarizine, but not by local anesthetics, tetrodotoxin, nitrendipine or omega-conotoxin GVIA. These results demonstrate that CHEB acts as a potent and effective secretogogue for glutamate by a pre-synaptic mechanism that does not require activation of Na+ channels or of L-type or N-type Ca2+ channels. Stimulation of spontaneous glutamate release may contribute to the convulsant properties of CHEB.     

Tripolar hip replacement for recurrent prosthetic dislocation

An innovative treatment is described for unstable total hip arthroplasty that uses a large inside diameter acetabular cup and a bipolar femoral head sized to approximate the diameter of the normal hip. Eight consecutive patients with recurrent prosthetic dislocations were treated with this tripolar hip. Joint stability was achieved in all patients, who have an average of 4.2-years' followup (range, 2.6-6.3 years).     

Flexible sigmoidoscopy training program for internal medicine residents

We examined the possibility of an association between the bacterial genotype of Escherichia coli O157:H7 and the likelihood of progression to neurological complications in childhood gastroenteritis-associated haemolytic uraemic syndrome (D+HUS). Bacterial stool isolates were available from 51 patients with HUS; 11 of these patients suffered a neurological complication. Bacteria were assessed for plasmid content, verotoxin (Shiga-like toxin) profile, verotoxin 2 subtype, and presence of the eaeA (effacement and attachment) marker. No association of bacterial genotype with central nervous system (CNS) manifestations was observed. Whilst the cause of CNS manifestations may be multifactorial, there is no evidence at present to implicate specific bacterial traits.     

Microsurgical thumb reconstruction with toe transfer: selection of various techniques

Microsurgical toe transfer is an established method for reconstruction of missing thumbs. However, there is little agreement on which of the various techniques represents the ideal transfer. Basically, selection of technique requires balancing the patient's functional needs, appearance of the reconstructed thumb, and donor-site cosmesis. Based on our experience with 103 toe-to-thumb transfers performed over the past 9 years, this paper attempts to provide guidelines for appropriate selection among the four most commonly employed toe transfer techniques (e.g., second toe, total great toe, great toe wrap-around, trimmed great toe) so that optimal results and patient's acceptance can both be achieved.     

The effect of various treatments in vitro and in vivo on the binding of 125I-labeled anti-rat serum albumin Fab'' to rat tissue polyribosomes

With 125I-labeled Fab' specific for rat liver serine dehydratase it has been possible to localize polyribosomes synthesizing the enzyme under several different environmental conditions. Evidence is presented to show that, following the administration of amino acids in vivo, the relative synthetic capabilities of free and membrane-bound polyribosomes synthesizing serine dehydratase vary with time. Early during the period of induction of the enzyme by administration of amino acids or by feeding a high protein diet the majority of the newly synthesized enzyme is derived from membrane-bound polyribosomes. Later in the induction process an increasing proportion of the enzyme is synthesized by the free polyribosomes. Subcellular localization studies clearly show that serine dehydratase is synthesized by both subclasses of hepatic membrane-bound polyribosomes, the loose and tight membrane-bound polyribosomes, as well as by the free polyribosomes. It was found that the membrane-bound polyribosomes are the preferential sites of synthesis of the majority of serine dehydratase molecules in the Morris hepatomas 5123C and 7800. It is concluded that the synthesis of the enzyme, serine dehydratase, in rat liver is not discretely compartmentalized in either class of free or membrane-bound polyribosomes. Rather, the relative proportions of the serine dehydratase synthesizing polyribosomes within these two classes of polyribosomes can vary depending on the metabolic and physiologic state of the liver cell.     

A new method of treatment for mallet finger. A preliminary report

An infant with a typical Edwards syndrome and a modal chromosome number of 46 is reported. In all cells analyzed one chromosome G was missing and an additional chromosome similar to a pair No. 16 was present. The phenotype of the child indicates that the extra element is a translocation between G and 18 chromosomes as in one case described previously.