Inhibition by a novel azole antifungal agent with a geranyl group on lanosterol 14 alpha-demethylase of yeast.

AFK-108 (1-[2-(2,4-dichlorophenyl)-2-((2E)-3,7-dimethylocta-2,6- dienyloxy)ethyl]-1H-imidazole) is a new imidazole derivative characterized by a geranyl substituent showing strong antifungal activity. Azole antifungal agents are known to be potent inhibitors of lanosterol 14 alpha-demethylase (P450(14)DM) of fungi. The role of the geranyl group of AFK-108 on interaction of AFK-108 with the target was studied by using Saccharomyces cerevisiae P450(14)DM as the model enzyme. AFK-108 and some of its derivatives bound to oxidized P450(14)DM with one-to-one stoichiometry and inhibited the demethylase activity. AFK-108 derivatives having the longer farnesyl or the shorter prenyl group showed lower affinity than AFK-108 for the enzyme. AFK-108 caused 100% inhibition at the equivalent concentration to P450(14)DM in the reaction mixture (0.07 microM), while the farnesyl derivative inhibited the activity by 60% at the same concentration. AFK-108 interfered with the binding of CO to the ferrous P450(14)DM. However, the interfering effect of the prenyl derivative was lower than that of AFK-108. Another AFK-108 derivative having the saturated 3,7-dimethyloctyl group was also a weaker inhibitor than AFK-108. These experiments suggest that the geranyl group of AFK-108 interacts with the substrate binding site of P450(14)DM that recognises the side chain of the substrate. AFK-108 is the first example of an azole derivative interacting with the side chain recognising region of the substrate binding site of P450(14)DM.     

Significance of prenatal diagnosis in a patient with a huge neck tumor.

Due to the great advancements in fetal ultrasonography, the number of prenatal diagnoses are increasing, greatly contributing to improved neonatal surgery. It is now relatively easy to detect huge fetal cystic masses, and we have experienced three cases with a huge neck tumor detected in utero, one case with teratoma and two cases with cystic hygroma. Each case was complicated by neonatal asphyxia, and the neonate needed resuscitation by means of endotracheal intubation. The infant with teratoma unfortunately died of respiratory distress due to compression of the trachea before a perinatal team could be organized. Although the remaining cases with cystic hygroma were treated by a perinatal team, one died 19 hours after birth and the other has survived with the aid of endotracheal intubation in the hospital for three years. In addition, all four cases of cystic hygroma detected antenatally in our institute, which were not delivered, also had fetal hydrops which suggested a general lymphatic derangement. Cystic hygroma detected in utero is considered to be different from that detected after birth, since the former is associated with genetic lymphatic derangement. Prenatal diagnosis enables such patients to survive the perinatal period, but may not improve the prognosis of fetal cystic hygroma so much.     

Clinical Evaluation of a New Type of Centrifugal Pump

Abstract: The major problems with existing centrifugal pumps are leakage, mechanical trauma, and thrombus formation. In consideration of these problems, a new compact centrifugal pump system was developed. The purpose of this study was to evaluate the new centrifugal pump system clinically. Ten patients underwent open heart surgery with a centrifugal pump or a roller pump. During surgery, hemodynamic and hematological data were obtained. A pulsatile assist device in the pump circuit was used in patients with severe heart disease. There was neither operative death nor hospital mortality, and there was no difference with regard to hemodynamic data between the two groups. The centrifugal pump group, however, had significantly lower hemolysis, especially during prolonged cardiopulmonary bypass. This centrifugal pump could also create sufficient pulsatile flow with a pulsatile assist device. Postoperative macroscopic and microscopic findings demonstrated the smooth surface of the pump without thrombus formation. This centrifugal pump system might be useful for prolonged cardiopulmonary bypass.     

Plasminogen activators and plasminogen activator inhibitor 1 before and after venous occlusion of the upper limb in thromboangiitis obliterans (Buerger's disease).

Plasma levels of plasminogen activators (t-PA, u-PA) and their inhibitor (PAI-1) were studied in patients suffering from Buerger's disease and healthy volunteers before and after 15 minutes of venous occlusion test. The baseline levels of t-PA in group of patients did not differ from those of controls. On the contrary patients with Burger's disease showed a marked increase in u-PA antigen concentrations with concomitant decrease in PAI-1 antigen levels. During venous stasis t-PA antigen concentrations increased in all subjects, however it was much pronounced in controls. Venous occlusion resulted in significant decrease in free PAI-1 levels in the group of patients only. In conclusion, Buerger's disease is associated with the endothelial derangement with increased u-PA release and decreased PAI-1 release, which does not influence the function of fibrinolytic system. The fact that the reduced response of the endothelium to release t-PA after venous stasis goes in parallel with marked decrease in PAI-1 antigen levels seems to suggest that patients suffering from Buerger's disease are not at high risk of intravascular fibrin deposition.     

Mouse monoclonal antibodies which recognize a human (beta 1-4)galactosyl-transferase associated with tumor in body fluids.

Mouse monoclonal antibodies against human (beta 1-4)galactosyl-transferase (GalT) purified from human ovarian tumor effusion fluids were prepared and characterized. GalT purified from normal human plasma showed a single diffused band in nondenaturing polyacrylamide gel electrophoresis, but GalT purified from human ovarian tumor effusion fluids showed several oligomeric bands and a monomeric band in nondenaturing polyacrylamide gel electrophoresis. These oligomeric bands were dissociated into monomer by urea treatment and polymerized by a 2-mercaptoethanol treatment. Nine monoclonal antibodies (MAb) were prepared by immunization of purified GalT from human ovarian tumor effusion fluids and classified into three groups. Type I MAbs (MAb8611, MAb8913, and MAb8919) reacted only to the GalT monomer. Type II MAbs (MAb4880, MAb8507, and MAb8628) reacted to both the GalT monomer and the GalT polymer. Type III MAbs (MAb7907, MAb8513, and MAb8677) reacted only to the GalT polymer. These MAbs except MAb7907 could recover GalT enzyme activity from effusion fluids by immunoprecipitation. A fraction passed through MAb8513 affinity chromatography still showed reactivity to MAb8919, demonstrating that an epitope of MAb8513 resides on a minor part of GalT. A sandwich immunoassay (MAb8513-MAb8628HRP) was developed, and serum samples from ovarian cancer patients and benign ovarian patients were tested. The levels of sandwich immunoassay of serum samples from cancer were elevated significantly compared to those from benign and did not necessarily correlate to total GalT enzyme activity in serum samples. These results suggested that MAb8513 (Type III) might recognize a unique GalT associated with tumor (GAT).     

Changes in water intake following hepatic vagotomy in young rats

Changes in water intake after hepatic vagotomy were examined in the body weights of 3 different rats (about 100, 200 and 280 g). The vagotomy reduced water intake only in the 100-g rats.     

gamma-Aminobutyric acid enhances the tone of human internal anal sphincter.

The effect of gamma-aminobutyric acid (GABA) on the human internal anal sphincter was investigated. Cumulative applications of GABA produced concentration-dependent contractions (10(-8)-10(-5) M) of the isolated human sphincter. Pretreatment with bicuculline (GABAA antagonist) turned them to relaxation. Muscimol, a GABAA agonist, induced concentration-dependent contractions (10(-8)-10(-5) M); however, baclofen (GABAB agonist, 10(-8)-10(-5) M) promoted concentration-dependent relaxation of the strips. These results suggested that both excitatory GABAA receptors and inhibitory GABAB receptors exist in the internal anal sphincter. Oral administration of sodium valproate (1600 mg/day), a GABA transaminase inhibitor, enhanced the anal canal resting pressure in 10 normal volunteers. Anal manometry showed a significant elevation in tonus without affecting amplitudes or frequencies. These results indicated that endogenous GABA, which was increased by sodium valproate, produced elevations in the anal canal resting pressure through its specific receptors in the human internal anal sphincter.     

Spermidine/Spermine N-Acetyltransferase, a New Biochemical Marker for Epithelial Proliferation in Rat Bladder

We examined the activity of spermidine/spermine N ¹-acetyltransferase (SAT), a rate-limiting enzyme of the biodegradation of polyamines, in N -butyl- N -(4–hydroxybutyI)nitrosamine-induced transitional cell carcinoma (TCC) and melamine-induced papillomatosis of rat bladder, and compared the activity to that of ornithine decarboxylase (ODC). Both activities were higher in both lesions than in control rats. The difference between SAT and ODC activities in cancerous tissue and papillomatosis was not significant. Cells stained for proliferating cell nuclear antigen (PCNA) were abundant in papillomatosis. TCC had areas with much PCNA. The results indicated that an elevation of SAT activity occurs in both reversible and irreversible proliferation of bladder epithelium and could be important in bladder carcinogenesis.