Mouse semaphorin H induces PC12 cell neurite outgrowth activating Ras-mitogen-activated protein kinase signaling pathway via Ca(2+) influx

We recently showed that mouse semaphorin H (MSH), a secreted semaphorin molecule, acts as a chemorepulsive factor on sensory neurites. In this study, we found for the first time that MSH induces neurite outgrowth in PC12 cells in a dose-dependent manner. Comparison of Ras-mitogen-activated protein kinase (MAPK) signaling pathways between MSH and nerve growth factor (NGF) revealed that these pathways are crucial for MSH action as well as NGF. K-252a, an inhibitor of tyrosine autophosphorylation of tyrosine kinase receptors (Trks), did not inhibit the action of MSH, suggesting that MSH action occurs via a different receptor than NGF. L- and N-types of voltage-dependent Ca(2+) channel blockers, diltiazem and omega-conotoxin, inhibited MSH-induced neurite outgrowth and MAPK phosphorylation in a Ca(2+)-dependent manner. A transient elevation in intracellular Ca(2+) level was observed upon MSH stimulation. These findings suggest that extracellular Ca(2+) influx, followed by activation of the Ras-MAPK signaling pathway, is required for MSH induced PC12 cell neurite outgrowth.

IgE reactivity to alpha1 and alpha2 chains of bovine type 1 collagen in children with bovine gelatin allergy

BACKGROUND

Anaphylactic reactions to measles, mumps, and rubella vaccines, including gelatin as a stabilizer, have been reported. It had been found that most of these reactions to live vaccines are caused by the bovine gelatin included in these vaccines. Gelatin mainly includes denatured type I collagen, which consists of alpha1 and alpha2 chains.

OBJECTIVE

The current study was designed to investigate the IgE reactivity to alpha1 and alpha2 chains of bovine type I collagen in gelatin-sensitive children.

METHODS

Serum samples were taken from 10 children who had anaphylaxis to the vaccines and high levels of specific IgE to bovine gelatin. Bovine type I collagen was isolated from bovine skin and then separated to alpha1 and alpha2 chains by column chromatography. IgE reactivity to denatured type I collagen and its alpha1 and alpha2 chains was analyzed by immunoblotting, ELISA, and histamine release from the mast cells passive sensitized with IgE antibodies in pooled serum of the children.

RESULTS

All children had specific IgE to bovine type I collagen. Furthermore, IgE antibodies in their sera reacted with the alpha;2 chain but not with the alpha1 chain. Similarly, the mast cells sensitized with pooled sera in the children showed alpha2 chain-specific histamine release but not alpha1 chain-specific histamine release.

CONCLUSION

In gelatin allergy denatured bovine type I collagen is a major allergen and IgE-binding sites exist in the alpha2 chain of type I collagen.

Stretch-activated ion channel blocker gadolinium attenuates ischemic ST-segment elevation in canine myocardium

Regional transmural ischemia causes both ST-segment elevation and systolic elongation (bulging) of the myocardium. Mechanical stretch might alter the transmembrane potential via stretch-activated ion channels (SAC); however, the role of SAC on ischemic ST-segment elevation has not yet fully studied. The present study investigated the role of SAC in the genesis of ischemic ST-segment elevation in the in-vivo canine heart. In 6 anesthetized dogs, an extracorporeal conduit connected to the left anterior descending coronary artery was occluded for 5 min before and after the intracoronary infusion of gadolinium (Gd, 500 micromol/min). To eliminate the effect of ischemic preconditioning, the bypass was occluded for 5 min before the experiment. Percent systolic shortening (%SS) and percent systolic elongation (%bulging) were measured using a pair of ultrasonic dimension crystals. A unipolar epicardial ECG was monitored at the center of the ischemic area for the measurement of the ST-segment level. At the end of coronary occlusion, there was no difference in the reduction of %SS or the increase of %bulging between before and after infusion of Gd. ST-segment elevation, however, was significantly attenuated by the infusion of Gd. These data demonstrated that the activation of SAC is one cause of ischemic ST-segment elevation.

Nonischemic ST-segment elevation induced by negative inotropic agents

The present study investigated whether regional ventricular dyskinesia (ie, systolic bulging) is a direct cause of ST-segment elevation in canine hearts in vivo. Regional ventricular dyskinesia was induced in 33 anesthetized open-chest dogs by injection of negative inotropic agents into the left anterior descending coronary artery (LAD) without disruption of coronary blood flow. Regional myocardial contraction was assessed in terms of the percent systolic shortening (%SS) and percent systolic bulging (%bulging), which were measured using ultrasonic crystals. The ST-segment elevation of the LAD-perfused area was measured with a unipolar electrode. Lidocaine, a sodium channel blocker, nicorandil, a potassium channel opener, propranolol, a beta-adrenergic blocker, or verapamil, a calcium channel blocker, was administered by intracoronary injection during maximal vasodilation induced by adenosine. All drugs induced dose-dependent ST-segment elevation in association with a parallel reduction in %SS and a parallel increase in %bulging. The absence of myocardial ischemia was confirmed by the absence of NADH fluorescence. It was concluded that regional ventricular dyskinesia had an important role in ST-segment elevation not associated with myocardial ischemia.

Screening for aetiology of thrombophilia: a high prevalence of protein S abnormality

We systematically screened for the aetiology of thrombophilia in 115 patients with venous, arterial and small vessel thromboses. Forty-one patients (36% of those we examined) suffering from a variety of thromboses, including deep vein thrombosis, pulmonary embolism, arterial occlusion, cerebral infarction, Moyamoya disease and ulcerative colitis, were characterized either with positive lupus anticoagulants or with decreased activities of protein S, protein C, antithrombin III and/or plasminogen. Eight mutation sites were confirmed in 11 thrombotic patients using gene analysis. Decreased protein S activity was found with a high incidence (23 out of 115) in Japanese patients who suffered from not only venous thrombosis but also arterial and small vessel thrombosis. We emphasize here the important role of protein S in the pathogenesis of thrombosis in the Japanese population.

Interaction of collagen molecules from the aspect of fibril formation: acid-soluble, alkali-treated, and MMP1-digested fragments of type I collagen

Collagen type I extracted with acid or digested with pepsin forms fibrils under physiological conditions, but this ability is lost when the collagen is treated with alkaline solution or digested with matrix metalloproteinase 1 (MMP1). When acid-soluble collagen was incubated with alkali-treated collagen, the fibril formation of acid-soluble collagen was inhibited. At 37 degrees C, at which alkali-treated collagen is denatured, the lag time was prolonged but the growth rate of fibrils was not affected. At 30 degrees C, at which the triple helical conformation of alkali-treated collagen is retained, the lag time was prolonged and the growth rate reduced. Heat-denatured alkali-treated collagen and MMP1-digested fragments have no inhibitory effect on the fibril formation of acid-soluble collagen. This means that the triple helical conformation and the molecular length are important factors in the interaction of collagen molecules and that alkali-treated collagen acts as a competitive inhibitor for fibril formation of collagen. We found that alkali-treated collagen and MMP1-digested fragments form fibrils that lack the D periodic banding pattern and twisted morphology under acidic conditions at the appropriate ionic strength. We also calculated the relative strengths of hydrophobic and electrostatic interactions between collagen molecules. When the hydrophobic interaction between linear collagen molecules was considered, we found a pattern of periodic maximization of the interactive force including the D period. On the other hand, the electrostatic interaction did not show the periodic pattern, but the overall interaction score affected fibril formation.

Futalosine and its derivatives, new nucleoside analogs

Futalosine, a new nucleoside analog, was isolated from a fermentation broth of Streptomyces sp. MK359-NF1. Some chemical derivatives of futalosine were prepared. 6-O-Methylfutalosine methylester inhibited growth of HeLa-S3 cells in vitro (IC50 = 19.5 micrograms/ml) in contrast to the weak activity of futalosine. 6-O-Methylfutalosine methylester at concentrations higher than 10 micrograms/ml inhibited incorporation of 3H-TdR and 3H-UR but not 3H-Leu in the acid-soluble fractions of HeLa-S3 cells.

Comparison of the effects of convulsant and depressant barbiturate stereoisomers on AMPA-type glutamate receptors

BACKGROUND

Alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA)-type glutamate receptors mediate fast excitatory synaptic transmission in the central nervous system. Although barbiturates have been shown to suppress the AMPA receptor-mediated responses, it is unclear whether this effect contributes to the anesthetic action of barbiturates. The authors compared the effects of depressant [R(-)] and convulsant [S(+)] stereoisomers of 1-methyl-5-phenyl-5-propyl barbituric acid (MPPB) on the AMPA and gamma-aminobutyric acid type A (GABA(A)) receptor-mediated currents to determine if the inhibitory effects on AMPA receptors correlate to the in vivo effects of the isomers.

METHOD

The authors measured whole-cell currents in the rat cultured cortical neuron at holding potential of -60 mV. Kainate 500 microM was applied as the agonist for AMPA receptors. Thiopental (3-300 microM), R(-)-MPPB or S(+)-MPPB (100-1,000 microM) was coapplied with kainate under the condition in which the GABA(A) receptor-mediated current was blocked. Effects of MPPB isomers on the current elicited by GABA 1 microM were studied in the separate experiments.

RESULTS

Thiopental inhibited the kainate-induced current reversibly and in a dose-dependent manner, with a concentration for 50% inhibition of 49.3 microM. Both R(-)-MPPB and S(+)-MPPB inhibited the kainate-induced current with a little stereoselectivity. R(-)-MPPB was slightly but significantly more potent than S(+)-MPPB. In contrast, R(-)-MPPB enhanced but S(+)-MPPB reduced the GABA-induced current.

CONCLUSIONS

Both convulsant and depressant stereoisomers of the barbiturate inhibited the AMPA receptor-mediated current despite of their opposite effects on the central nervous system in vivo. Although thiopental exhibited a considerable inhibition of AMPA receptors, the results suggest that the inhibition of AMPA receptors contributes little to the hypnotic action of the barbiturates.

The effects of two antiinflammatory pretreatments on bacterial-induced lung injury

BACKGROUND

Two antiinflammatory therapies that have been effective in preventing acid-induced lung injury were evaluated. Specifically, their effects on a subsequent bacterial-airspace challenge were compared. Bacteria were instilled 24 h after acid-induced lung injury. Pseudomonas aeruginosa PAO-1 was used as the bacteria, because its effects in healthy lungs was documented previously.

METHODS

New Zealand white rabbits were anesthetized and three pretreatments were administered: (1) pentoxifylline pretreatment (a 20-mg/kg bolus dose and then 6 mg x kg(-1) x h(-1) given intravenously), (2) 1 ml anti-tumor necrosis factor alpha antiserum given intravenously, or (3) normal saline given intravenously. The pretreatment doses were shown previously to prevent acid-induced lung injury. Then 1.2 ml/kg hydrochloric acid (HCl), pH 1.25, was instilled into the rabbits' right lungs. All the animals underwent mechanical ventilation for 8 h. Twenty-four hours after the acid instillation, the rabbits were anesthetized again and 2 ml/kg (10(9) colony forming units/ml) PAO-1 was instilled into their left lungs. The rabbits' breathing was aided by mechanical ventilation for another 8 h, and then they were killed and exsanguinated.

RESULTS

Both pretreatments attenuated the acid-induced lung injury of the noninstilled left lungs. Arterial oxygen tension and the lung edema of pretreated, acid-exposed animals were significantly and almost equally improved (compared with no pretreatments) by either of the pretreatments. However, when the bacteria were instilled into the left lungs 24 h after the acid injury, the pentoxifylline pretreatment but not the anti-tumor necrosis factor alpha pretreatment prevented much of the bacteria-induced lung injury. Pentoxifylline pretreatment significantly improved the measurements of left lung edema and epithelial and endothelial permeability. There was also a trend for improved oxygenation in the pentoxifylline-pretreated and infected animals. In contrast, the anti-tumor necrosis factor alpha pretreatment did not prevent the bacteria-induced lung injury and increased some of the measurements of lung injury.

CONCLUSIONS

Two antiinflammatory therapies that prevented acid-induced lung injury to the noninstilled left lungs had significantly different effects on a subsequent bacteria-induced lung injury to the left lungs. The therapies differed in their mechanism of tumor necrosis factor alpha blockade, and this may have affected the bacteria-induced injury to the lungs.

Alkali-treated collagen retained the triple helical conformation and the ligand activity for the cell adhesion via alpha2beta1 integrin

Alkaline treatment is a good method for extracting collagen with high recovery even from an aged animal specimen. However, the properties of collagen treated under alkaline conditions have not been well established yet. By the treatment with a solution of 3% sodium hydroxide and 1.9% monomethylamine, the isoelectric point of type I collagen was lowered from 9.3 to 4.8 because of the conversions of Asn and Gln to Asp and Glu. With the acidification of the pI, the denaturation temperature of the collagen was decreased from 42 to 35 degrees C after 20 d treatment, but the collagen-specific triple helical conformation was maintained. Human keratinocytes and fibroblasts adhered to the alkali-treated collagen via the collagen receptor integrin alpha2beta1. This indicates that the alkali-treated collagen maintained its property as a biological adherent molecule. Unlike acid-soluble collagen, alkali-treated collagen lost the ability to form fibrils at neutral pH under physiological conditions. This ability was lost even after 4 h of alkaline treatment, when the denaturation temperature of the collagen did not change. On the other hand, the alkali-treated collagen formed a fibrous precipitate with a uniform diameter of 50-70 nm under acidic conditions at 30 degrees C.

Troglitazone upregulates nitric oxide synthesis in vascular smooth muscle cells

We investigated the effects of troglitazone on cytokine-stimulated nitric oxide (NO) production in cultured rat vascular smooth muscle cells (VSMC). The increase in NO formation caused by interleukin-1alpha (IL-1) was enhanced by troglitazone in a concentration-dependent manner. Bacterial lipopolysaccharide-stimulated NO synthesis was also increased by troglitazone. The combinations of IL-1, tumor necrosis factor-alpha, or lipopolysaccharide with interferon-gamma (IFN) were strong stimuli for induction of NO synthesis in VSMC, which were further potentiated by the presence of troglitazone. When troglitazone was added at increasing intervals after the stimulation of VSMC with IL-1, the enhancement in NO production decreased as the interval lengthened, suggesting that troglitazone alters NO synthase (NOS) expression by VSMC rather than having a direct affect on VSMC NOS activity. Troglitazone had no effect on IL-1-elicited or IL-1/IFN-elicited nuclear factor-kappaB activity in VSMC. Troglitazone inhibited the degradation of cytokine-induced NOS mRNA. Thus troglitazone appears to enhance IL-1-induced NOS mRNA levels by prolonging its half-life rather than activating its transcription, which is nuclear factor -kappaB-dependent. No expression of peroxisome proliferator-activated receptor-gamma (PPARgamma) was detected in VSMC, and 15-deoxy-D12,14 prostaglandin J2, the natural ligand for the PPARgamma, did not resemble the effect of troglitazone on IL-1-induced NO synthesis. These results indicate that troglitazone upregulates cytokine-stimulated NO synthesis in VSMC through PPARgamma-independent mechanisms. Considering its inhibitory effects on the action of numerous growth factors on VSMC, the direct vascular effects of troglitazone shown in this study may have important implications for prevention of restenosis and possibly atherosclerosis.

Laminin 5 promotes activation and apoptosis of the T cells expressing alpha3beta1 integrin

By introducing an alpha3 gene-containing plasmid into a human T cell line Jurkat, we prepared the T cells, which express a high level of the alpha3beta1 integrin, to assess the role of laminin 5 in the skin immune system. The alpha3beta1-expressing T cells adhered to laminin 5 and exhibited spreading. These adhered T cells showed a significant tyrosine phosphorylation of intracellular proteins including p59(fyn) upon T-cell receptor (TCR) stimulation. Six hours after cross-linking TCR, these cells on laminin 5 secreted a three times higher level of IL-2 than those on a BSA-coated plate. Twenty hours after the stimulation, 48% of the alpha3beta1-expressing T cells on laminin 5 caused apoptosis. The protein level of cyclin D3 and E decreased, while that of p53 increased in these T cells. These data suggest that laminin 5 may play at least two regulatory roles for T cell functions: augmentation of IL-2 production by antigen-stimulated T cells and induction of apoptosis in these T cells.

Experimental gene therapy against subcutaneously implanted glioma with a herpes simplex virus-defective vector expressing interferon-gamma

We investigated the feasibility of local treatment or tumor vaccination with a herpes simplex virus (HSV) type 1-defective vector. The vector was engineered to express murine interferon-gamma (IFN-gamma) for experimental gene therapy against mouse glioma Rous sarcoma virus (RSV). The murine IFN-gamma gene was driven by the cytomegalovirus promoter. The helper virus (tsk) was thermosensitive; consequently, this vector could only proliferate at 31 degrees C. A high level of murine IFN-gamma expression was confirmed in vitro and in vivo by immunohistochemistry using anti-mouse IFN-gamma monoclonal antibody. This engineered vector (dvHSV/MulFN-gamma) inhibited the proliferation of mouse glioma RSV cells in vitro, and an intratumoral (i.t.) local injection of the vector caused i.t. necrosis in vivo. The immunological effect of dvHSV/MulFN-gamma was also examined in a mouse glioma RSV cell implantation model. A subcutaneous (s.c.) implant of 1 x 10(6) mouse glioma RSV cells after treatment with dvHSV/MulFN-gamma was rejected. However, the implant after treatment with an engineered HSV-defective vector containing an antisense nucleotide sequence of the murine IFN-gamma gene was not rejected. In addition, in another group of mice in which RSV cells treated with dvHSV/MulFN-gamma were implanted into a femoral (s.c.) region and nontreated RSV cells were implanted into a contralateral femoral (s.c.) region, the implanted RSV cells were rejected. The rejection of the implanted mouse glioma RSV was blocked by anti-asialo GM1, which was known to inhibit natural killer cell activity. These results revealed that the HSV-defective vector could realize a high efficiency of transfection to glioma cells through short-time treatment, and that the IFN-gamma gene transferred to the cells had the effect of tumor vaccination, which was suggested be related to natural killer cells. In conclusion, dvHSV/MulFN-gamma may be useful for the gene therapy of malignant glioma through either i.t. local injection or a practical tumor vaccination with ex vivo gene transfer.

Chloride channel CLCN5 mutations in Japanese children with familial idiopathic low molecular weight proteinuria

BACKGROUND

Familial idiopathic low molecular weight proteinuria (FILMWP) is a renal proximal tubulopathy characterized by mild proteinuria consisting of low molecular weight proteinuria and relatively conserved renal function in young patients, but without rickets. Mutations in the renal chloride channel CLCN5 gene have been reported in three disorders of hypercalciuric nephrolithiasis and in FILMWP.

METHODS

To assess the relationship between molecular defects and phenotypic variations, we analyzed the CLCN5 gene from three additional Japanese families with FILMWP using single-strand conformation polymorphism and sequencing.

RESULTS

We identified three mutations: a single base insertion at codon 514; a single base deletion at codon 116; and a nonsense mutation, R704X. The R704X mutation is identical to that found in X-linked recessive nephrolithiasis, but there was no renal failure in our patient. The first two mutations caused a shift in the reading frame, and all introduced a premature stop codon, resulting in synthesis of truncated CLC-5 proteins that lacked 220 (29%), 610 (82%), and 43 (6%) amino acids, respectively. These mutations were demonstrated to cosegregate with the disease in each of the three families.

CONCLUSIONS

We conclude that the CLCN5 gene is responsible for the renal proximal tubulopathy in many Japanese families and suggest that molecular defects, environmental factors, or other modifying genes may account for the different phenotypes.

A controlled trial of combined therapy for newly diagnosed severe childhood IgA nephropathy. The Japanese Pediatric IgA Nephropathy Treatment Study Group

The most appropriate treatment for patients with IgA nephropathy is controversial. Treatment with prednisolone, azathioprine, heparin-warfarin, and dipyridamole early in the course of disease may prevent immunologic renal injury in children with severe IgA nephropathy. To determine whether similar results can be obtained with a combination of just heparin-warfarin and dipyridamole, the effects of such treatment were compared to those of treatment with prednisolone, azathioprine, heparin-warfarin, and dipyridamole in 78 children with newly diagnosed IgA nephropathy showing diffuse mesangial proliferation. The patients were randomly assigned to receive either prednisolone, azathioprine, heparin-warfarin, and dipyridamole for 2 yr (group 1) or heparin-warfarin and dipyridamole for 2 yr (group 2). All of the 40 patients in group 1 and 34 of the 38 patients in group 2 completed the trial. The mean urinary protein excretion fell in group 1 patients (P < 0.0001), but remained unchanged in group 2 patients. The mean serum IgA concentration was reduced in group 1 patients (P = 0.0002), but was unchanged in group 2 patients. BP and creatinine clearance were normal at the end of the trial in all but one group 2 patient, who developed chronic renal insufficiency. The percentage of glomeruli showing sclerosis was unchanged in group 1 patients, but increased in group 2 patients (P = 0.006). The intensity of mesangial IgA deposits decreased in group 1 patients (P = 0.02), but remained unchanged in group 2 patients. In conclusion, the present study shows that treatment of children with severe IgA nephropathy with prednisolone, azathioprine, heparin-warfarin, and dipyridamole for 2 yr early in the course of disease reduces immunologic renal injury and prevents increase of sclerosed glomeruli.

A novel human RasGAP-like gene that maps within the prostate cancer susceptibility locus at chromosome 1q25

We report the molecular cloning of a human cDNA that encodes a molecule having striking homology with Ras-specific GTPase-activating proteins (RasGAPs). Among previously described RasGAPs, the cDNA product is most closely related to Caenorhabditis elegans GAP-2, including a predicted coiled-coil structure near the carboxyl terminus. Expression of the cDNA in Saccharomyces cerevisiae defective in one of two RasGAPs, Ira2, complemented loss of the Ira2 function, indicating that the cDNA product functions as a RasGAP. The RasGAP-like gene is located on the human chromosome 1q25, the locus that appears to contain a hereditary prostate cancer susceptible gene, HPC1.

[Standard versus long-term prednisolone with sairei-to for initial therapy in childhood steroid-responsive nephrotic syndrome: a prospective controlled study]

The most appropriate initial treatment for children with steroid-responsive nephrotic syndrome is controversial. Initial treatment with 18-week prednisolone and the Chinese herbal medicine. Sairei-to, may prevent subsequent relapse. To determine whether similar results can be obtained with a combination of just initial 8-week prednisolone and Sairei-to, we compared the effects of such treatment with those of treatment with 18-week prednisolone and Sairei-to in 196 children with steroid-responsive nephrotic syndrome. The patients were randomly assigned to receive 8-week (group 1) or 18-week (group 2) prednisolone for the initial therapy. All patients received Sairei-to for 2 years in addition to prednisolone. Eighty-eight of the 98 patients in group 1 and 83 of the 98 patients in group 2 completed their trial. At entry, the two groups of patients did not differ in their clinical and laboratory findings. During the 2-year trial, 62 group 1 patients (70%) and 54 group 2 patients (65%) had relapses, and 19 group 1 patients (21%) and 20 group 2 patients (24%) had frequent relapses. The present study demonstrates that a combination of initial 8-week prednisolone and 2-year Sairei-to is effective in children with steroid-responsive nephrotic syndrome.

The G protein G alpha12 stimulates Bruton's tyrosine kinase and a rasGAP through a conserved PH/BM domain

Heterotrimeric guanine-nucleotide-binding proteins (G proteins) are signal transducers that relay messages from many receptors on the cell surface to modulate various cellular processes. The direct downstream effectors of G proteins consist of the signalling molecules that are activated by their physical interactions with a G alpha or Gbetagamma subunit. Effectors that interact directly with G alpha12 G proteins have yet to be identified. Here we show that G alpha12 binds directly to, and stimulates the activity of, Bruton's tyrosine kinase (Btk) and a Ras GTPase-activating protein, Gap1m, in vitro and in vivo. G alpha12 interacts with a conserved domain, composed of the pleckstrin-homology domain and the adjacent Btk motif, that is present in both Btk and Gap1m. Our results are, to our knowledge, the first to identify direct effectors for G alpha12 and to show that there is a direct link between heterotrimeric and monomeric G proteins.

L-selectin-specific autoantibodies in murine lupus: possible involvement in abnormal homing and polarization of CD4+ T cell subsets

One notable functional abnormality in murine and human systemic lupus erythematosus (SLE) is the defect in the production of IL-2 in association with the deficit in naive CD4+ T cells. The mechanism is unknown, but one idea is that naturally occurring autoantibodies with specificities to the naive CD4+ T cell subpopulation are related to this event. We selected hybridoma monoclonal autoantibodies from SLE-prone (New Zealand Black (NZB) x New Zealand White (NZW))F1 mice that reacted with restricted populations of CD4+ T cells. One of these, H32, was specific for L-selectin, as determined by 1) distribution of Ag H32 on lymphoid cells similar to Mel-14, an epitope of L-selectin; 2) shedding of 80-kDa molecules with epitope H32 from the surface of lymph node cells coincidentally with Mel-14, when stimulated with phorbol ester; 3) cross-inhibitory activities on Ag binding between H32 and Mel-14; and 4) reactivity of H32 with recombinant mouse L-selectin. Pretreatment of 51Cr-labeled lymphocytes from BALB/c mice with H32 significantly inhibited their homing to lymph nodes in vivo. The BALB/c splenic H32+ CD4+ T cell subset produced few cytokines except IL-2, thus corresponding to naive ThP-type cells. This subset was markedly selectively depleted in aged (NZB x NZW)F1 mice. There was an age-associated increase in frequencies and titers of anti-L-selectin autoantibodies in sera from (NZB x NZW)F1 mice. Thus, abnormalities of naive CD4+ T cell subset, including IL-2 production in subjects with SLE, are at least partly attributed to the generation of autoantibodies to L-selectin.

Effect of additional general anesthesia with propofol, midazolam or sevoflurane on stress hormone levels in hysterectomy patients, receiving epidural anesthesia

Hormonal responses after surgery are characterized by increased pituitary-adrenal axis hormones. We undertook this study to determine whether the choice of anesthesia influences stress hormone levels. Twenty-three adult females scheduled for hysterectomy for benign disease under general anesthesia were randomly assigned to one of three groups: epidural/propofol anesthesia (Group P), epidural/midazolam anesthesia (Group M), and epidural/sevoflurane anesthesia (Group S). The concentrations of ACTH and cortisol in group P and group M were significantly less than that of group S at 60 min after the incision. The concentrations of beta-endorphin and aldosterone in group P and group M were significantly less than that of group S at 60 min after the incision and after extubation. We conclude that combined epidural and general anesthesia with propofol or midazolam has a greater suppressive effect than sevoflurane on the stress response of the pituitary-adrenal axis during hysterectomy.

Moyamoya disease with concurrent von Recklinghausen's disease and cerebral arteriovenous malformation

We present a rare autopsy case of von Recklinghausen's disease with Moyamoya vessels and arteriovenous malformation. A 58-year-old female patient suffered from dysarthria and dysphagia. On examination, Parkinson's signs, pseudobulbar palsy, and muscular weakness of the left extremity and pyramidal tract signs were observed. An enhanced brain computed tomography revealed abnormal high-density network vessels at the thalamus and midbrain. By cerebral angiography, the following changes were observed; occlusion of the right internal carotid artery at the bifurcation, and abrupt narrowing and occlusion of the left internal carotid artery at the bifurcation and siphon. A lateral vertebral arteriography revealed telangiectasia at the basilar tip. The patient died of pulmonary thromboembolism at age 61. The vessels of the circle of Willis were hypoplastic. The optic nerves, infundibulum and mammillary body were covered with a large number of ectastic vessels. Arteriovenous malformations were observed in the bilateral occipital lobes. Histopathologically, the elastic lamina of Moyamoya vessel was conspicuously wavy and often duplicated or triplicated, and discontinued occasionally. Discontinuity of the elastic lamina of the perforating arteries and circumferential arteries supplied by the middle cerebral artery (MCA), anterior CA (ACA) and posterior CA (PCA), was also occasionally observed. It is likely that the Moyamoya vessels in this patient were compensatorily formed by congenital hypoplasia of the internal artery, MCA, ACA and PCA.

Involvement of prolonged ras activation in thrombopoietin-induced megakaryocytic differentiation of a human factor-dependent hematopoietic cell line

Thrombopoietin (TPO) is a hematopoietic growth factor that plays fundamental roles is both megakaryopoiesis and thrombopoiesis through binding to its receptor, c-mpl. Although TPO has been shown to activate various types of intracellular signaling molecules, such as the Janus family of protein tyrosine kinases, signal transducers and activators of transcription (STATs), and ras, the precise mechanisms underlying TPO-induced proliferation and differentiation remain unknown. In an effort to clarify the mechanisms of TPO-induced proliferation and differentiation, c-mpl was introduced into F-36P, a human interleukin-3 (IL-3)-dependent erythroleukemia cell line, and the effects of TPO on the c-mpl-transfected F-36P (F-36P-mpl) cells were investigated. F-36P-mpl cells were found to proliferate and differentiate at a high rate into mature megakaryocytes in response to TPO. Dominant-negative (dn) forms of STAT1, STAT3, STAT5, and ras were inducibly expressed in F-36P-mpl cells, and their effects on TPO-induced proliferation and megakaryocytic differentiation were analyzed. Among these dn molecules, both dn ras and dn STAT5 reduced TPO- or IL-3-induced proliferation of F-36P-mpl cells by approximately 30%, and only dn ras could inhibit TPO-induced megakaryocytic differentiation. In accord with this result, overexpression of activated ras (H-rasG12V) for 5 days led to megakaryocytic differentiation of F-36P-mpl cells. In a time course analysis on H-rasG12V-induced differentiation, activation of the ras pathway for 24 to 28 h was required and sufficient to induce megakaryocytic differentiation. Consistent with this result, the treatment of F-36P-mpl cells with TPO was able to induce prolonged activation of ras for more than 24 h, whereas IL-3 had only a transient effect. These results suggest that prolonged ras activation may be involved in TPO-induced megakaryocytic differentiation.

Structural elements of Trimeresurus flavoviridis serum inhibitors for recognition of its venom phospholipase A2 isozymes

Five inhibitors (PLI-I-V) against Trimeresurus flavoviridis (Tf, habu snake, Crotalinae) venom phospholipase A2 (PLA2) isozymes have been isolated from its serum. PLI-I, which is composed of two repeated three-finger motifs, and PLI-IV and PLI-V, which contain a sequence similar to the carbohydrate recognition domain (CRD) of C-type lectins, were expressed in the forms fused with glutathione S-transferase (GST). The resulting GST-PLIs showed ability to bind to three Tf venom PLA2 isozymes. The binding study with the truncated forms indicated that one of two three-finger motifs of PLI-I was able to bind to PLA2 isozymes. The N-terminal 37-amino acid fragment and the CRD-like domain of PLI-IV and PLI-V were bound to PLA2 isozymes. On the other hand, their C-terminal 12-amino acid segment also associated with PLA2 isozymes. When either of two units of a hydrophobic tripeptide in this sequence was replaced by trialanine, the binding was completely abolished, indicating that the C-terminal hydrophobic cores of PLI-IV and PLI-V were critically responsible for the binding to venom PLA2 isozymes.

Diagnosis of squamous cell carcinoma arising from mature cystic teratoma of the ovary

BACKGROUND

The prognoses of patients with squamous cell carcinoma of the ovary are quite poor. However, preoperative diagnosis is difficult due to the rarity of this tumor and its similarity to mature cystic teratoma (MCT). The objective of this study was to assess the value of tumor markers and clinical characteristics in making a differential diagnosis between MCT and squamous cell carcinoma arising from MCT.

METHODS

Between September 1979 and June 1996, 37 patients with ovarian squamous cell carcinoma arising from MCT were treated by the Tokai Ovarian Tumor Study Group. The authors evaluated tumor markers, tumor size, and age as parameters for differentiation between MCT and squamous cell carcinoma arising from MCT. Diagnostic efficiency was calculated as the sensitivity multiplied by the specificity.

RESULTS

There were significant differences (P < or = 0.0002) in age, tumor size, and levels of squamous cell carcinoma antigen (SCC), CA125, and CEA, as well as a significant difference (P < or = 0.0396) in the CA19-9 level between MCT and squamous cell carcinoma arising from MCT. Diagnostic efficiency was highest for SCC (63.0%), followed by CA125 (50.7%). Receiver operating characteristic (ROC) curves demonstrated that CEA was the best screening marker for squamous cell carcinoma arising from MCT, whereas age and tumor size were better markers than CA125 or CA19-9. The optimal cutoff values for age and tumor size were 45 years and 99 mm, respectively, according to ROC analysis.

CONCLUSIONS

These findings demonstrate that age and tumor size are important factors in making a differential diagnosis. In addition, SCC and CEA levels should be measured in patients age 45 years or older who have an MCT-like ovarian tumor larger than 99 mm in greatest dimension.

Retrotransposable CR1-like elements in crotalinae snake genomes

A part of the 3'-flanking region of BP-II gene, which is one of Trimeresurus flavoviridis venom gland phospholopase A2 (PLA2) isozyme genes, has a region homologous to avian chicken repeat 1 (CR1)-element. In the present study, ten CR1-like elements were further identified in T. gramineus venom gland PLA2 isozyme genes, T. flavoviridis PLA2 inhibitor (PLI) genes, and T. flavoviridis and T. gramineus TATA-box binding protein (TBP) genes. Southern blot analysis using a probe for CR1 showed that Crotalinae snake genomes contain a number of CR1-like elements.

Diagnosis of squamous cell carcinoma arising from mature cystic teratoma of the ovary

BACKGROUND

The prognoses of patients with squamous cell carcinoma of the ovary are quite poor. However, preoperative diagnosis is difficult due to the rarity of this tumor and its similarity to mature cystic teratoma (MCT). The objective of this study was to assess the value of tumor markers and clinical characteristics in making a differential diagnosis between MCT and squamous cell carcinoma arising from MCT.

METHODS

Between September 1979 and June 1996, 37 patients with ovarian squamous cell carcinoma arising from MCT were treated by the Tokai Ovarian Tumor Study Group. The authors evaluated tumor markers, tumor size, and age as parameters for differentiation between MCT and squamous cell carcinoma arising from MCT. Diagnostic efficiency was calculated as the sensitivity multiplied by the specificity.

RESULTS

There were significant differences (P < or = 0.0002) in age, tumor size, and levels of squamous cell carcinoma antigen (SCC), CA125, and CEA, as well as a significant difference (P < or = 0.0396) in the CA19-9 level between MCT and squamous cell carcinoma arising from MCT. Diagnostic efficiency was highest for SCC (63.0%), followed by CA125 (50.7%). Receiver operating characteristic (ROC) curves demonstrated that CEA was the best screening marker for squamous cell carcinoma arising from MCT, whereas age and tumor size were better markers than CA125 or CA19-9. The optimal cutoff values for age and tumor size were 45 years and 99 mm, respectively, according to ROC analysis.

CONCLUSIONS

These findings demonstrate that age and tumor size are important factors in making a differential diagnosis. In addition, SCC and CEA levels should be measured in patients age 45 years or older who have an MCT-like ovarian tumor larger than 99 mm in greatest dimension.

Developmental changes in carbonic anhydrase II in the rat kidney

We examined the distribution and maturational changes of carbonic anhydrase I (CAI) and carbonic anhydrase II (CAII) in microdissected nephron segments of Sprague-Dawley rats. CAI and CAII proteins were measured by enzyme-linked immunosorbent assay. CAI was not detected in any nephron segment in 7-week-old rats. CAII was present in the collecting ducts, proximal tubules, and thick ascending limbs of loop of Henle in 7-week-old rats. CAII contents were significantly higher in the early proximal tubules (S1) than in second (S2) and late (S3) portions of the proximal tubules, while the contents in S1 were less than in cortical collecting ducts (CCD), outer stripe and inner stripes of the outer medullary collecting ducts (OMCDo and OMCDi). CAII content in each of S1, CCD, and OMCD of 1-week-old rats was only 14% or less of that of adults, but increased steeply during the 2nd and 3rd weeks of life, reaching almost 40% at 3 weeks of age and 97% at 7 weeks. Our results indicate that CAII is present throughout the entire nephron of the rat, and that CAII content in S1, CCD, and OMCD increases exponentially during the first 7 weeks of life. Our data suggest that the immature low levels of CAII may explain, at least in part, the limited capacity of urinary acidification during neonatal life. Further studies are necessary to establish the role of such changes in CAII content in acid-base homeostasis during neonatal life.

Specific detection of phosphatidylinositol 3,4,5-trisphosphate binding proteins by the PIP3 analogue beads: an application for rapid purification of the PIP3 binding proteins

Phosphatidylinositol (PI) 3-kinase is known as one of the key molecules involved in the various biological events such as vesicle trafficking, cytoskeletal rearrangements and cell survival. T clarify the molecular basis underlying these events, we have tried to identify the proteins that can interact with phosphatidylinositol 3,4,5-trisphosphate (PIP3), the lipid product of PI3-kinase. Using a new PIP3 analogue, PIP3-APB, we synthesized an affinity column for PIP3 binding proteins. This enabled us to purify and identify several PIP3 binding proteins such as Tec tyrosine kinase, Gap1m, and Akt, as the candidates for the downstream molecules of PI3-kinase. All of these proteins contain PH domains, possible binding sites for phospholipids. Studies with various deletion mutants of Tec or Gap1m revealed that their PH domains are indeed the binding sites for PIP3. These results demonstrate that this PIP3-analogue binds various PIP3 binding proteins with high specificity and may be useful to elucidate the downstream mechanisms of PI3-kinases-mediated signaling pathways.

The complete cDNA coding sequence for the bovine proalpha2(I) chain of type I procollagen

The complete sequence of the cDNA for the pro alpha2(I) chain of bovine type I procollagen is presented. The encoded amino acid sequence shows 92.0% identity to the human pro alpha2(I) collagen chain.

Liver bilirubin UDP-glucuronosyltransferase activity in chronic nonhemolytic unconjugated hyperbilirubinemia of adults

Ten adult patients with chronic nonhemolytic unconjugated (indirect) hyperbilirubinemia were analyzed by determining bilirubin uridine diphosphate-glucuronosyltransferase activity according to a more physiological and sensitive method (9 control cases, 0.457 +/- 0.163 nmole/mg protein/min). There was no overlap of the enzyme activities of 2 cases with Crigler-Najjar syndrome (type II) (0.006 nmole/mg protein/min on average) and 6 cases with Gilbert's syndrome (0.051 +/- 0.016 nmole/mg protein/min). The enzyme activities in 2 patients with post-hepatitic hyperbilirubinemia were within the normal range. A new classification of nonhemolytic unconjugated hyperbilirubinemia in adults is proposed according to the results of this enzyme activity and the recent data on the gene mutation of this enzyme.

Loss of neurofibromin in the leptomeningeal astroglial heterotopia of NF-1

Neurofibromin, the protein product of the neurofibromatosis type 1 (NF-1) gene, has important roles in tumor suppression or normal embryogenesis. Cerebellar leptomeningeal astroglial heterotopia (LAH) is a proliferation of heterotopic astroglial cells and fibers in the cerebellar leptomeninges, which is characteristically demonstrated in the NF-1 patients. In this study, neurofibromin expression was investigated in NF-1 and non-NF-1 human tissues, especially in the cerebellum of NF-1 patients. Neurofibromin was found by immunoblotting in the CNS but not in the heart, liver, and kidney. Immunohistochemistry in the normal areas of the brains with NF-1 demonstrated neurofibromin immunoreactivity as did the brains of unaffected controls. Cerebellar LAH showed no neurofibromin immunoreactivity. The results of this study suggest that neurofibromin expression remains unchanged in the nonproliferated region of the CNS of the NF-1 patient but changes occur in the abnormally proliferated region, resulting in cerebellar LAH. Loss of neurofibromin may result in the excessive migration and growth of astrocytes in the early fetal period.

Intracellular distribution of the Wilson's disease gene product (ATPase7B) after in vitro and in vivo exogenous expression in hepatocytes from the LEC rat, an animal model of Wilson's disease

In patients with Wilson's disease, both copper incorporation into ceruloplasmin and excretion of this metal into bile are impaired. These conditions are caused by a genetic defect in the Wilson's disease gene (ATP7B). To investigate the Wilson's disease gene protein (ATPase7B) in hepatocytes, we constructed an expression plasmid carrying full-length complementary DNA for human Wilson's disease gene and attempted to express the gene in hepatocytes of LEC rats, an animal model of Wilson's disease. Transfection of hepatocytes, either in vitro or in vivo, was done using a newly developed cationic liposome containing 1,4-bis(3-(N-hexadecyl) aminopropyl) piperazine. Immunological analyses of human ATPase7B with specific monoclonal antibodies showed human ATPase7B to be a membrane protein with a molecular mass of 155 kd. Analysis of human ATPase7B expressed in hepatocytes from LEC rats suggested that this protein is present in the trans-Golgi network and at the plasma membrane, a distribution pattern similar to that of Menkes' disease protein (ATPase7A). These findings suggest that these two putative copper-transporting P-type ATPases function similarly at the cellular level. Cotransfection and coexpression of the human Wilson's disease gene and ceruloplasmin gene in cultured hepatocytes indicate that the distribution of ceruloplasmin is always accompanied by ATPase7B at the perinuclear region, but that part of ATPase7B localizes irrespective of the distribution of ceruloplasmin. Based on these investigations, we propose that ATPase7B exists in the trans-Golgi network and transports copper into this compartment. This seems to ensure an appropriate delivery of copper to the apoceruloplasmin. On the other hand, part of ATPase7B that is not accompanied by ceruloplasmin in the perinuclear region and at the plasma membrane seems to contribute to efflux of this metal from the hepatocytes. Thus the distribution patterns of ATPase7B in hepatocytes may explain the dual roles of this P-type ATPase in hepatocytes.

Distribution of platinum in human gynecologic tissues and pelvic lymph nodes after administration of cisplatin

BACKGROUND

Defining tissue accumulation of platinum may be of importance, since it may provide a pharmacological explanation for organ-specific cisplatin activity. This study was conducted to evaluate the efficacy of cisplatin at the tissue level in different gynecologic organs. The doses administered were equivalent to those used in neoadjuvant chemotherapy regimens.

STUDY DESIGN

Cisplatin was administered intravenously to patients with cervical or endometrial cancer 1 h before operation, and platinum accumulations in tissues were assayed by the atomic absorption method.

RESULTS

Platinum accumulation was highest in the cervix and next highest in the myometrium in both cancers. Platinum accumulation in ovary and lymph node was only 0.58 and 0.57 times that in the myometrium, respectively. In patients with cervical cancer, the platinum accumulations in the myometrium and cervix were significantly higher than in the ovary and lymph node. Platinum accumulation in cervical cancer tissue was lower than in the myometrium and cervix, suggesting that delivery of cisplatin to a cervical cancer is somewhat more difficult than to the normal cervix. In patients with endometrial cancer, there was significantly more accumulation in the cervix than in the ovary and lymph node.

CONCLUSIONS

These data indicated that cisplatin was easily distributed to the cervix and myometrium, but not to the ovary, lymph node, and cancer tissues.

Neurotrophin-3 prevents death of axotomized Clarke's nucleus neurons in adult rat

In the present investigation, we studied whether neurotrophin-3 (NT-3) contributes to the rescue of axotomized Clarke's nucleus (CN) neurons in adult rats. A significant (24%) loss of CN neurons occurred at L-1 ipsilateral to T-8 hemisection by 14 days, which reached 31% at 2 months and then stabilized. Axotomized CN neurons had also atrophied by 14 days, but mean cell size did not decrease further. Animals that received gelfoam soaked in nerve growth factor, brain derived neurotrophic factor, or ciliary neurotrophic factor at the lesion site also showed a 30% neuron loss at 2 months, and a 40% reduction in average cell area. Rats receiving NT-3 showed a 15% neuron loss, which was not improved by additional neurotrophins in combination with NT-3. None of the treatments prevented neuron atrophy. Bioassay of the gelfoam showed that NT-3 bioactivity remained at 5 days after surgery but not at 14 days. Additional rats with hemisections that received NT-3 continuously via mini-pump for 2 months showed a 15% neuron loss, the same as with NT-3 given via gelfoam. These results indicate that even limited exposure of axotomized CN neurons to NT-3 produces permanent rescue of 50% of the neurons. The virtually complete rescue that we had previously observed with transplants of fetal central nervous system (CNS) tissues may, therefore, be due at least in part to NT-3, but the exogenous administration of a single neurotrophic factor or a combination of neurotrophic factors is less effective than transplants in producing long-term survival of axotomized CNS neurons.

Geographical variation of mandible size and shape in the Ryukyu wild pig (Sus scrofa riukiuanus)

We measured adult mandibles of Ryukyu wild pigs from Amami-Oshima, Kakeroma, Okinawa, Ishigaki and Iriomote Islands. The size cline was not statistically recognized among the populations of Nansei Islands. The Ishigaki population was significantly larger than Iriomote one in mandible length. Some measurement ratios indicated that the ramus is enlarged laterally and that the body of mandible is dorso-ventrally developed in Ishigaki and Iriomote populations. The Amami-Oshima mandibles were relatively smaller than those of Okinawa and Iriomote populations in length item of body of mandible. These results will contribute to the zoo-archaeology on the historical change of size and shape in the island populations, and to the evolutionary biology on the morphological adaptation of this animal.

Necrotizing funisitis: clinical significance and association with chronic lung disease in premature infants

OBJECTIVES

Our purpose was to analyze the clinical significance of necrotizing funisitis, an unusual type of chronic inflammation of the umbilical cord, and to determine whether necrotizing funisitis is associated with chronic lung disease in premature infants.

STUDY DESIGN

A total of 52 perinatal factors were prospectively assessed in 18 pregnant women and their fetuses in cases of chorioamnionitis at delivery occurring at 22 to 30 gestational weeks; a statistical comparison between the necrotizing funisitis group (n = 5) and the group without necrotizing funisitis (n = 18) was carried out.

RESULTS

Significant correlations were found between necrotizing funisitis and the following factors: maternal serum C-reactive protein level on admission (p = 0.014), fetal distress (p = 0.044), umbilical artery blood pH value (p = 0.037) and polynuclear neutrophilic leukocyte count at birth (p = 0.014), chronic lung disease (p = 0.035), need for dexamethasone therapy for chronic lung disease (p = 0.029), duration of oxygen supplementation (p = 0.026), and length of hospital stay (p = 0.026).

CONCLUSIONS

There was a significant association between necrotizing funisitis and development of chronic lung disease, suggesting that necrotizing funisitis is an important risk factor for the development of chronic lung disease.

Defective adenoassociated viral-mediated transfection of insulin gene by direct injection into liver parenchyma decreases blood glucose of diabetic mice

The present study assessed the feasibility of transferring the insulin gene into liver cells of diabetic individuals using a defective adenoassociated viral (AAV) vehicle. AAV offers several advantages over other viral vectors, since this vehicle can facilitate transfection in vivo without cell division and without any viral coding sequences (thus minimizing inflammation). The rat insulin gene and lacZ were each packed into a defective AAV vehicle (AAV-INS and AAV-lacZ, respectively). Successful AAV-mediated transfection and expression of lacZ into hepatocytes in primary cell culture were demonstrated by chemiluminescent assay of beta-galactosidase. Similarly, AAV-mediated transfection and expression of the insulin gene into hepatocytes was demonstrated by immunocytochemistry and reverse-transcriptase polymerase chain reaction (RT-PCR). After AAV-mediated transfection of the insulin gene into hepatocytes, glucose in the medium was significantly reduced for up to 5 days. After direct injection of AAV-INS into liver parenchyma of diabetic mice, successful transfection was demonstrated by RT-PCR, and blood glucose was significantly decreased for at least 6 days. These studies suggest that the AAV vector may be used to transfer the insulin gene into liver cells in vitro and in vivo.

Induction of ST-segment elevation by regional myocardial stretch in normal canine hearts in vivo

The purpose of this study was to evaluate ST-segment elevation induced by regional myocardial stretch without myocardial ischemia in canine hearts. A strain gauge arch (TH-601T) was sutured to the left ventricular epicardium, parallel to the short axis, to shorten the end-diastolic length of the myocardium beneath the arch (stretch zone; SZ) and to produce regional myocardial stretch in each of 6 dogs. An increase in preload caused by altering the height of a saline-filled reservoir affected prolongation or shortening of the myocardium both in the SZ and outside the arch (normal zone; NZ) to increase myocardial stretch. An epicardial electrocardiogram was recorded in both the SZ and the NZ. After suture of the strain gauge arch, the ST segment was elevated in the SZ. An increase in preload augmented stretch during systole in the SZ, resulting in additional ST-segment elevation. These results suggest that regional myocardial stretch itself plays an important role in ST-segment elevation.

[Etiological analysis of thrombophilia]

We have established a system for etiological analysis of thrombophilia which includes assays of antithrombin III, protein C, protein S, plasminogen, fibrinogen, heparin cofactor II and lupus anticoagulants as well as gene analysis. The analysis conducted on 115 patients with venous thrombosis, arterial thrombosis and small vessel thrombosis revealed that forty-one patients(36% of the examined patients) were accompanied with decreased activities of protein S, protein C, antithrombin III and plasminogen. Eleven candidate causal mutations were found by gene analysis. These studies indicate that a comprehensive examination is instrumental in identifying and confirming the etiology in patients with thrombophilia.

Differential effects of thiopental on neuronal nicotinic acetylcholine receptors and P2X purinergic receptors in PC12 cells

BACKGROUND

PC12 cells, derived from rat pheochromocytoma, express neuronal nicotinic acetylcholine receptors (nAchRs) and P2X purinergic receptors, both of which resemble the receptors in postganglionic sympathetic neurons. The former is the established and the latter is the putative receptor to mediate fast synaptic transmission. The authors investigated effects of thiopental on these two ligand-gated ion channels.

METHODS

Whole cell currents were recorded in PC12 cells without treatment of nerve growth factor, using conventional whole cell patch clamp technique. Nicotine or adenosine triphosphate (ATP) 30 microM was applied for 4-5 s in the absence or presence of thiopental 3-300 microM.

RESULTS

Nicotine induced the rapidly decaying inward current at -60 mV, which exhibited the characteristics of the neuronal nAchR-mediated current. Thiopental inhibited the nicotine-induced inward current and accelerated the current decay in a dose-dependent manner, resulting in the greater effects on the steady current than the peak current. IC50s for the peak and steady current were 56.7 and 7.4 microM, when the anesthetic was coapplied with nicotine. Thiopental's inhibition was not associated with a change in the reversal potential and was voltage-independent at membrane potential of -30 to -70 mV. Most of thiopental's effects seemed to require channel opening. In contrast to the nicotine-induced current, thiopental had little effect on the current elicited by ATP.

CONCLUSIONS

Thiopental, whose reported EC50 for general anesthesia is 25 microM, inhibited the neuronal nAchR-mediated current but not the P2X receptor-mediated response in PC12 cells at clinically relevant concentrations. Inhibition may result in suppression of synaptic transmission in sympathetic ganglia.

Characterization and evolution of a gene encoding a Trimeresurus flavoviridis serum protein that inhibits basic phospholipase A2 isozymes in the snake's venom

The proteins that bind phospholipase A2 (PLA2) isozymes of Trimeresurus flavoviridis (habu snake, crotalinae) venom were fractionated from sera on four columns, each conjugated with one of four PLA2 isozymes. Five proteins, termed PLA2 inhibitors (PLI) I-V, were obtained as the binding components. The combinations of the binding components differed depending on the PLA2 isozymes. PLI-IV and PLI-V correspond to PLI-A and PLI-B, respectively, which were known to bind to a major [Asp49]PLA2, PLA2, and contained a segment similar to the carbohydrate-recognition domain of C-type lectins. PLI-I, which is a major component of inhibitory proteins against three basic PLA2 isozymes, PLA-B (a basic [Asp49]PLA2) and basic proteins I and II (both [Lys49]PLA2s), has been isolated, and its partial amino acid sequence has been determined. A cDNA encoding PLI-I was isolated from a T. flavoviridis liver cDNA library and sequenced. PLI-I cDNA encoded 200 amino acid residues, including a signal peptide of 19 amino acid residues. One sugar chain was predicted to occur at position 157. A gene coding for PLI-I was isolated. It is 9.6-kb long and consists of five exons and four introns. Comparison of the exon-intron structure of the PLI-I gene with those of genes encoding urokinase-type-plasminogen-activator receptor (uPAR), Ly-6, CD59 and neurotoxins showed that they have characteristic unit encoding approximately 90 amino acid residues, which is divided over two exons. This strongly suggests that the PLI-I gene belongs to the uPAR, Ly-6, CD59 and neurotoxin gene family. There are two types of structurally different inhibitors against PLA2 isozymes in T. flavoviridis serum with different evolutionary origins.

Mutations in the CLCN5 gene in Japanese patients with familial idiopathic low-molecular-weight proteinuria

Familial idiopathic low-molecular-weight proteinuria (FILMWP) is a renal proximal tubulopathy that occurs predominantly in males. FILMWP is characterized by mild proteinuria consisting of low-molecular-weight proteinuria, aminoaciduria and relatively conserved renal function, but without rickets. To determine whether FILMWP is related to the CLCN5 gene, which is responsible for Dent's disease and two related disorders, we analyzed the CLCN5 gene from four Japanese families with FILMWP. We identified two novel mutations: one was a single base insertion at codon 520 serine in exon 10 and the other was a single base deletion at codon 403 tyrosine in exon 8. These mutations caused a shift in the reading frame, resulting in synthesis of truncated CLC5 proteins that lacked 220 (29%) and 314 (42%) amino acids, respectively. These mutations were demonstrated to cosegregate with the disease in two families, respectively. We conclude that the CLCN5 gene is responsible for this proximal renal tubulopathy in some Japanese families and that FILMWP is possibly a variant of Dent's disease.

Thrombophilia found in patients with moyamoya disease

Sixteen patients with Moyamoya disease and four with quasi-Moyamoya disease were investigated in order to elucidate the presence of thrombophilia. The assay system for diagnosing thrombophilia consisted of assessing both the activity and antigen levels of antithrombin III, protein C, protein S, fibrinogen and plasminogen as well as detecting lupus anticoagulants. The analysis revealed that one third (four definite cases and three quasi-cases) of the examined patients demonstrated either congenital or acquired thrombotic tendency. Protein C deficiency was found in two definite cases and in two quasi-cases among whom one quasi-case was identified to have a hereditary type I Protein C deficiency. Protein S deficiency was found in one definite case and in one quasi-case. Type II plasminogen deficiency was found in one quasi-case, and lupus anticoagulant was present in one quasi-case. Based on these findings, an evaluation of thrombophilia should thus be performed when both diagnosing and treating suspected cases of Moyamoya disease.