[Tissue type plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) in transplanted kidneys]

We have studied the involvement of fibrinolysis in acute rejection after kidney transplantation by analyzing changes in urinary levels of substances such as FDP, D-dimer, tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI). Fibrinolytic activity was found to be low (that is, PAI is dominant) during acute rejection, and it was elevated (that is, PA became dominant) as acute rejection subsided. It appears that the dominance of PA leads to an increase in the products of fibrinolysis and an elevation in the D-dimer/FDP ratio, resulting in disappearance of the acute rejection. Based on these findings, we thought it necessary to administer t-PA to kidney recipients so that PA becomes dominant earlier and the acute rejection can be reduced. It is necessary for us to directly study the phenomena within the kidneys. Therefore, we recently conducted a histochemical study of the distribution of t-PA, Urokinase type PA (u-PA) and PAI in transplanted kidneys. Transplanted kidney, which functioned well or showed signs of acute or chronic rejection, were biopsied. These renal samples as well as control samples (biopsied from normal nongrafted kidney) were examined as to distribution of t-PA, u-PA and PAI by the indirect enzyme complement method. In conclusion, t-PA, u-PA and PAI were detected in the glomeruli, arterioles, tubule and interstices of the control kidneys, well functioning grafts, acutely rejected grafts chronically rejected grafts. All samples showed intense chromatic responses in the arterioles and part of the tubules. On the whole, the chromatic response tended to be more intense in the acute rejection group than in the other group.

Acute and subacute inhalation toxicity of diborane in male ICR mice

To clarify the toxicity of diborane, we conducted acute (15 ppm for 1, 2, 4 or 8 h) and subacute (5 ppm for 2 or 4 weeks) inhalation studies on ICR mice. The concentration resulting in a 50% kill after 4 h exposure was 31.5 ppm. Body weight gain was suppressed and the lung weight was increased in diborane-exposed mice in both acute and subacute studies. In the acute study, diffuse pan bronchiolitis-like lesions developed in the lung in various degrees depending on exposure time, which can be pathologically characterized as infiltration of inflammatory cells into the terminal bronchioles and surrounding alveoli, pulmonary congestion and bleeding and/or edema. In the subacute study, we observed lymphoid hyperplasia in the perivascular and peribronchial areas, and infiltration of macrophage and plasma cells into the alveoli. In the mice exposed for 4 weeks, the lesions were more severe than in those exposed for 2 weeks, consisting of hyperplasia and desquamation of Clara cells. In the nasal cavity, we saw mucous exudate and inflammatory cells, suggesting irritation caused by diborane. The histopathological findings, except for the respiratory organs, did not reveal any exposure-related changes. No significant changes were seen in hematological and serum biochemical examinations either. In conclusion, the target organ of diborane inhalation is the respiratory organs, particularly the lung. Further inhalation experiments are essential to investigate the safety exposure levels of diborane.

No-observed-effect level of diborane on the respiratory organs of male mice in acute and subacute inhalation experiments

In order to clarify the acute and subacute toxicity of diborane (B2H6, CAS: 19287-45-7) at low concentrations, male ICR mice were exposed to diborane for 1, 2, 4 or 8 h at concentrations of 1 or 5 ppm (phase I study), and for 6 h/day, 5 days/wk, over 2 or 4 wk at concentrations of 0.02 or 0.7 ppm (phase II study). Hematological and biochemical tests, and histopathological examinations of the cornea, nasal mucosa, respiratory tract and lung were carried out. All mice in both studies survived until they were sacrificed. In the phase I study, lung weight increased significantly in mice exposed to 5 ppm of diborane for 8 h. Histopathologically diffuse panbronchiolitis-like lesion was observed in mice exposed to 5 ppm of diborane for 2, 4 or 8 h. In the phase II study, slight infiltration of polymorphous neutrophil was observed mainly in the peribronchiolar region in mice exposed to 0.2 ppm or 0.7 ppm of diborane for 2 or 4 wk. In both studies, hematological and biochemical examinations failed to reveal any exposure-related changes. These results suggest that no-observed-effect level of diborane inhalation on the respiratory organs were 1 ppm in acute exposure, but 0.2 ppm of diborane inhalation for 2 or 4 wk seems to be unsafe.

Purification and characterization of an alkaline amylopullulanase with both alpha-1,4 and alpha-1,6 hydrolytic activity from alkalophilic Bacillus sp. KSM-1378

The novel alkaline amylopullulanase produced by alkalophilic Bacillus sp. KSM-1378 was purified to an electrophoretically homogeneous state from culture medium. The purified enzyme was a glycoprotein with an apparent molecular mass of about 210 kDa and an isoelectric point of pH 4.8. The N-terminal amino acid sequence was Glu-Thr-Gly-Asp-Lys-Arg-Ile-Glu-Phe-Ser-Tyr-Glu-Arg-Pro and showed no homology to the N-terminal regions of other amylopullulanases reported to date. The enzyme was able to attack specifically the alpha-1,6 linkages in pullulan to generate maltotriose as the major end product, as well as the alpha-1,4 linkages in amylose, amylopectin and glycogen to generate various oligosaccharides. The pH and temperature optima for the pullulanase and alpha-amylase activities were pH 9.5 and 50 degrees C and pH 8.5 and 50 degrees C respectively. Both activities were strongly inhibited by well characterized inhibitors, such as diethyl pyrocarbonate and N-bromosuccinimide. The pullulanase activity was specifically inactivated by Hg2+ ions, alpha-cyclodextrin and beta-cyclodextrin while the amylase activity was strongly inhibited by EDTA and EGTA, although inhibition could be reversed by Ca2+ ions. It is suggested that the single alkaline amylopullulanase protein has two different active sites, one for the cleavage of alpha-1,4-linked substrates and one for the cleavage of alpha-1,6-linked substrates.

Protective effects of soy protein on the peroxidizability of lipoproteins in cerebrovascular diseases

To study the mechanism of dyslipoproteinemia, lipoproteins [very low density lipoprotein (VLDL), low density lipoprotein (LDL) and high density lipoprotein (HDL)] were isolated from stroke patients and healthy persons by ultracentrifugation. Lipoproteins were dialyzed into copper dichloride solution to study the effects of soycreme administration on lipoprotein peroxidation. Blood was drawn from 15 patients with cerebral thrombosis who were not administered soycreme, 10 patients with cerebral thrombosis who were administered soycreme and 11 healthy persons. The lipoproteins were dialyzed into 5 mol/l copper dichloride solution for various lengths of time, and then lipid constituents in the lipoproteins were measured by thin-layer chromatography. After the dialysis, percentages of cholesteryl ester and triglyceride in various lipoproteins decreased significantly (P < 0.05 or 0.01) in both patient groups and in healthy persons. Spot X1 was found between triglyceride and free fatty acid on the thin-layer chromatography, and spot X2 was located between free fatty acid and free cholesterol after dialysis. Spots X1 and X2 reflect lipoprotein peroxidation. Percentages of these spots were higher in VLDL, LDL and HDL in the patient groups than in the healthy subjects. Soycreme administration suppressed the appearance of spots X1 and X2. Furthermore, blood cholesterol concentrations were reduced by the administration of soy protein. Thus, soy may be useful in the prevention and/or treatment of atherosclerosis.

Transformation of cultured human monocytes by peroxidized low-density lipoprotein

To study the roles of peroxidized low-density lipoprotein (pox-LDL) during the formation of foam cells from human monocytes, monocytes isolated from normal human blood were incubated with RPMI alone, normal low-density lipoprotein (n-LDL) and copper pox-LDL. The concentrations of total cholesterol (TCH) and lipid peroxide in the human monocyte medium did not change significantly after incubation with RPMI medium alone or n-LDL, but those of TCH decreased slightly after incubation with pox-LDL for 24 h. Triglyceride (TG) concentrations in the culture medium of human monocytes decreased after incubation with all above substances. Ultrastructural studies showed that the monocytes changed to macrophages after incubation with RPMI alone or n-LDL and to foam cells after incubation with pox-LDL for 48 h. We conclude that TGs may be metabolized for ATP production by human monocytes. The energy may play a role in the transformation of monocytes to macrophages, and pox-LDL can induce transformation of monocyte-derived macrophages to foam cells.

No-effect level of subacute tetraethoxysilane inhalation on the mouse kidney

To determine safe exposure levels of tetraethoxysilane (TEOS) in the kidney, groups of male ICR mice (SPF grade) containing 10 animals each were exposed to TEOS, 100 ppm or 50 ppm, for 6 hours/day, 5 days/week, for 2 or 4 weeks. Tubulo-interstitial nephritis developed in mice exposed to 100 ppm for 2 and 4 weeks, but no kidney lesions or renal function changes were observed in mice exposed to 50 ppm. However, histopathological changes were detected in the nasal mucosa of mice exposed to 50 ppm TEOS. These results indicate that the occupational exposure level for TEOS should be strictly maintained below the current recommended exposure limit, 10 ppm, set by many countries and academic associations, and that renal tubular function of TEOS-exposed workers should be assessed and monitored for a long period.

A new glucuronide saponin from tea leaves (Camellia sinensis var. sinensis

A new glucuronide saponin (1) was isolated as its methyl ester (2) from the leaves of Camellia sinensis var. sinensis. On the basis of its spectral data and the results of chemical degradation, the structure was elucidated to be 3-O-[beta-D-galactopyranosyl(1-->2)-[beta-D- xylopyranosyl(1-->2)-alpha-L-arabinopyranosyl(1-->3)]- beta-D-glucuronopyranosyl]-21-O-cinnamoyl-16,22-di-O-acetylbarr ingtogenol C.

Ionic properties of IK,n in outer hair cells of guinea pig cochlea

The ionic properties of voltage-dependent K+ current activated at the resting membrane potential (IK,n) of outer hair cells (OHC) isolated from the guinea pig cochlea were studied using a patch-clamp technique in a whole-cell recording mode. The reversal potential of IK,n indicated a high selectivity for K+, and the relative permeability ratios for various monovalent cations were K+:Rb+:NH4+ = 1:1.21:0.13. Decrease in extracellular Cl- inhibited the IK,n. IK,n was blocked by Cs+ and Ba2+, although the inhibitory manner of Cs+ and Ba2+ were voltage-dependent and voltage-independent, respectively. By the use of puff-application method, the local application of Ba2+ to basolateral surface of OHC shifted the holding current level in an inward direction, whereas the application to apex and hair showed little change. Indicating that the IK,n channels preferentially locate at the basolateral region of cell membrane.

Artificial endocrine pancreas and optimal blood glucose regulation in diabetic patients--from bedside-type to wearable-type

The artificial endocrine pancreas is a feedback control system regulating insulin delivery on a minute-by-minute basis according to the measured blood glucose levels. The bedside-type artificial endocrine pancreas has been proven to be useful not only as a therapeutic tool for diabetes mellitus but also as an elegant research tool for investigating the pathophysiology of the disease. With significant advances in the development of a subcutaneous tissue glucose monitoring system, the wearable-type artificial endocrine pancreas has been applied to diabetic patients. With this system, perfect glycemic control can be obtained for longer periods in ambulatory diabetic patients. The trend in the development of the artificial endocrine pancreas is now directed to implantable devices. Much efforts have been conducted to realize these devices.

A Drosophila homolog of cadherin associated with armadillo and essential for embryonic cell-cell adhesion

We have identified a Drosophila homolog of vertebrate classic cadherins. A monoclonal antibody to Drosophila alpha-catenin (D alpha-catenin) copurifies a 150-kDa glycoprotein (gp150) along with the alpha-catenin. To further characterize this protein, we generated monoclonal antibodies to gp150 and isolated its cDNAs using the antibodies. Predicted sequences of the encoded product revealed that it is a transmembrane protein with similarity to vertebrate classic cadherins, and so we designated this molecule DE-cadherin. The extracellular domain has six cadherin-specific repeats, although the first repeat seems to be cleaved off upon maturation, and the cytoplasmic domain shows significant identity to that of vertebrate classic cadherins. DE-cadherin is distinguishable from its vertebrate counterparts by a large insertion with local sequence similarity to Fat, laminin A chain, Slit, and neurexin I at the proximal region of the extracellular domain. Despite such differences, DE-cadherin is functionally similar to vertebrate classic cadherins. For example, it is associated with alpha-catenin and beta-catenin (Armadillo), and protected from trypsin digestion only in the presence of Ca2+, as is the case for many of classic cadherins. Transfection of S2 cells with the DE-cadherin cDNA enhances their Ca(2+)-dependent cell aggregation. Antibodies to this molecule inhibited aggregation of not only the transfectants but also early embryonic cells. DE-cadherin is concentrated at the apical poles of epithelial cell-cell junctions. All these results suggest that DE-cadherin is a homolog of vertebrate classic cadherins and that the vertebrate and invertebrate share common mechanisms for regulation of cell-cell adhesion.

Drosophila mutants in the 55 kDa regulatory subunit of protein phosphatase 2A show strongly reduced ability to dephosphorylate substrates of p34cdc2

The 55 kDa regulatory subunit of Drosophila protein phosphatase 2A is located in the cytoplasm at all cell cycle stages, by the criterion of immunofluorescence. We are unable to detect significant change in protein phosphatase activity during the nuclear division cycle of syncytial embryos. However, cell cycle function of the enzyme is suggested by the mitotic defects exhibited by two Drosophila mutants, aar1 and twinsP, defective in the gene encoding the 55 kDa subunit. The reduced levels of the 55 kDa subunit correlate with the loss of protein phosphatase 2A-like, okadaic acid-sensitive phosphatase activity of brain extracts against caldesmon and histone H1 phosphorylated by p34cdc2/cyclin B kinase, but not against phosphorylase a. Thus the mitotic defects of aar1 and twinsP are likely to result from the lack of dephosphorylation of specific substrates by protein phosphatase 2A.

Effect of gonadotropin-releasing hormone agonist on the bone mineral density of patients with endometriosis

OBJECTIVE

To examine changes in bone mineral density (BMD) of patients treated with GnRH agonist (GnRH-a) by dual-energy X-ray absorptiometry and to understand factors related to bone loss.

DESIGN

Prospective controlled trial examining BMD during and after GnRH-a therapy every 24 weeks for 18 months in patients with endometriosis compared with nontreated controls.

SETTING

Outpatients clinic at a university hospital and its affiliated outpatient clinic.

PATIENTS

Twenty-two patients with endometriosis as GnRH-a-treated group, 12 healthy women with normal menstrual cycle, and 7 patients with mild endometriosis as control group.

INTERVENTIONS

Patients were treated with a GnRH-a (buserelin acetate) at 900 micrograms/d by nasal spray for 24 weeks.

RESULTS

The significance of differences in change-rates at all measured points in both groups was assessed by analysis of variance. The interaction between treatment and period was significant, and only week 24 of the GnRH-a-treated group was significantly lower compared with baseline. The reduction rate of BMD was high in patients 33 years of age or younger compared with those who were 34 years of age or older. According to a multiple-regression model, the most important factor related to bone loss was the post-treatment serum levels of E2.

CONCLUSION

At the end of treatment, BMD was significantly lower than that of the control group, and the reduction rate was 3.4%. A factor related to bone loss was degree of ovarian suppression.

Augmented expression of inflammatory cytokines and adhesion molecules in accelerated nodulosis during methotrexate therapy

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[A prospective randomized trial of adjuvant chemotherapy with UFT for head and neck carcinoma. Head and Neck UFT Study Group]

A prospective randomized trial was performed in 67 institutions for the purpose to evaluate the efficacy of adjuvant chemotherapy after radical treatment of head and neck carcinoma. A comparison was made between the following two groups; one-year oral administration of UFT, 300 mg/day, after radical treatment (UFT group); and a non-treatment group. Patients were classified under the following three categories; 1) stage II-IV, receiving radical surgery; 2) stage II, receiving radical radiotherapy; and 3) nasopharyngeal cancer. The numbers of cases were 424, 111 and 25, respectively, and they were randomized into two groups. The numbers of eligible cases were 398, 105 and 25, respectively. Statistical analysis was performed in the cases receiving radical surgery and in those receiving radical radiotherapy. As the results, in cases receiving radical surgery no significant difference was observed in 3-year survival rates (77.9% for UFT group vs 72.9% for non-treatment group) or 3-year relapse-free rates (73.4% for UFT group vs 66.2% for non-treatment group) between the two groups. However, the distant relapse rate was significantly lower in the UFT group than in the non-treatment group (7.9% vs 14.6%; p = 0.034). In the cases receiving radical radiotherapy, no significant differences was observed in either 3-year survival rates or 3-year relapse-free rates. Thus it was suggested that UFT maintenance therapy might suppress the distant metastasis after radical surgery. We considered a further confirmative trial for patients at high risk of distant metastasis after radical surgery to be advisable.

Alternative cell fate choice induced by low-level expression of a regulator of protein phosphatase 2A in the Drosophila peripheral nervous system

The Drosophila gene twins encodes the regulatory B subunit of type 2A protein phosphatase. Here we report that its partial loss-of-function mutations caused abnormal morphogenesis in the adult peripheral nervous system. In wild-type flies, the mechanoreceptor, one major class of sensory organs, is composed of four specialized cells (one neuron and three accessory cells) that are derived from a single precursor cell. The hypomorphic twins mutations did not block division of this precursor, but most likely altered cell fate in this lineage to produce only accessory cells that form sensory structures. Stepwise reductions of twins protein enhanced this transformation. In these mutants, another regulatory subunit, A, and the catalytic subunit, C, of the phosphatase were expressed at normal levels. Therefore, the modulation of the phosphatase activity by the B subunit appears to be crucial for specification of neural cell identity.

Development of a miniaturized glucose monitoring system by combining a needle-type glucose sensor with microdialysis sampling method. Long-term subcutaneous tissue glucose monitoring in ambulatory diabetic patients

OBJECTIVE

To develop a reliable and practical glucose monitoring system by combining a needle-type glucose sensor with a microdialysis sampling technique for long-term subcutaneous tissue glucose measurements.

RESEARCH DESIGN AND METHODS

A microdialysis Cuprophan hollow-fiber probe (inner diameter, 0.20 mm; length, 15 mm) was perfused with isotonic saline solution (120 microliters/h) and glucose concentrations in the dialysate were measured by a needle-type glucose sensor extracorporeally. This system was tested both in vitro and in vivo. Subcutaneous tissue glucose concentrations were then monitored continuously in 5 healthy and 8 diabetic volunteers for 7 to 8 days. A hollow-fiber probe was inserted into the abdominal subcutaneous tissue.

RESULTS

This monitoring system achieved excellent results in vitro. Subcutaneous tissue glucose concentrations were measured in a wide range from 1.7 to > 27.8 mM glucose, with a time delay of 6.9 +/- 1.2 min associated with a rise in glucose and 8.8 +/- 1.6 min with a fall in the glucose level (means +/- SE). The overall correlation between subcutaneous tissue (Y) and blood (X) glucose concentration was Y = 1.08X + 0.19 (r = 0.99). The subcutaneous tissue glucose concentration could be monitored precisely for 4 days without any in vivo calibrations and for 7 days by introducing in vivo calibrations.

CONCLUSIONS

Glycemic excursions could be monitored precisely in the subcutaneous tissue by this microdialysis sampling method with a needle-type glucose sensor in ambulatory diabetic patients.

Alcoholysis of epsilon-decalactone with polyethylene glycol-modified lipase in 1,1,1-trichloroethane

Lipase from Pseudomonas cepacia was modified with 2,4-bis[O-methoxypoly(ethylene glycol)]-6-chloro-s-triazine, activated PEG2, to form PEG-lipase. The PEG-lipase is soluble and active in organic solvents. It catalyzes alcoholysis of racemic epsilon-decalactone with ethanol in 1,1,1-trichloroethane to form (R)-hydroxydecanoic acid ethyl ester. No alcoholysis of (S)-decalactone takes place. These results were discussed in relation to carbon number of n-alcohol, optimum temperature and comparison with modified and non-modified lipases.

[Ureteral polyps: three case reports]

We observed recently three cases of ureteral polyps including a case of multiple polyps. The first patient was a 33-year-old man with multiple polyps at the left upper ureter. The second patient was a 51-year-old man and the third 49-year-old man, and both cases were complicated with ureteral stones. We divided 88 ureteral polyps reported in Japan from 1970 to 1990 into polyps in children and those in adults. We further divided the individual polyps into single and multiple polyps and examined them clinically. Characteristic findings were obtained in polyps in children; namely, multiple polyps were dominant, almost all of them occurred at the left upper ureter and no cases were complicated with ureteral stones. Furthermore, many of the multiple polyps in adults occurred at the left upper ureter and few were complicated with stones as in the children. In conclusion, the ureteral polyps in children and multiple ureteral polyps in adults were similar in character and we presumed that some congenital factors might be involved in their occurrence.

Cranial reshaping of rare concordant dizygotic twins with trigonocephaly

Craniofacial surgery for craniosynostosis is now often performed, and many cases have been reported. Twinning among these cases is of particular interest. An extremely rare case of cranial reshaping of concordant dizygotic twins with trigonocephaly is described in this report.

Direct effects of gonadotropin-releasing hormone on the ovary in rats and humans

In order to know whether gonadotropin-releasing hormone (GnRH)-like substances play a role as local regulators in the ovary, localization of the GnRH receptor, and the effects of GnRH agonist (GnRHa) on the cyclic AMP system in the rat ovary was studied. In addition, effects of GnRH antagonist on the rat ovary and effects of GnRHa on steroidogenesis in the human ovary were also examined. In the rat, localization of the GnRH receptor was observed to change with follicular development, and GnRHa decreased follicle-stimulating-hormone-stimulated cAMP production. On the other hand, GnRH antagonist showed the tendency to promote ovarian function. In the human ovary, GnRHa seemed to inhibit steroidogenesis directly, in vivo and in vitro. These data suggested that GnRH/GnRH-like substances play a role as local regulators in the ovary.