An infant with both autoimmune neutropenia and idiopathic thrombocytopenia with IgG2/IgA deficiency

We report an infant with autoimmune neutropenia (AIN), idiopathic thrombocytopenia (ITP), and IgG2/IgA deficiency. The patient was referred to our hospital at 5 months of age because of epistaxis and generalized petechiae. Physical examination revealed moderate hepatosplenomegaly. A complete blood count revealed a platelet count of 2.0 x 10(3) cells/microliters, and a white cell count of 3,600 cells/microliters, with severe neutropenia (less than 1% bands and segmented cells). Neutrophils and platelets adhering to megakaryocytes were decreased in the bone marrow. Tests for serum neutrophil-binding IgG (NB-IgG) and platelet-associated IgG (PA-IgG) were positive. A diagnosis of both AIN and ITP was made and therapy with intact-type gamma-globulin and prednisolone was initiated. Improvement occurred, but was temporary. A lack of serum IgA and IgG2 was noted during the clinical course. The patient has not been susceptible to bacterial infections but has had a severe clinical course with rubella and chickenpox.

Experimental and clinical studies on the intraperitoneal administration of cis-diamminedichloroplatinum (II) for peritoneal carcinomatosis caused by gastric cancers

The effectiveness of the intraperitoneal administration of cis-diamminedichloroplatinum (II) (DDP) on peritoneal carcinomatosis caused by gastric cancers was evaluated. Seventeen patients were treated with one of three protocols, consisting of the intraperitoneal injection (ip) of DDP at doses of 70 and 110 mg/m2, with or without sodium thiosulfate (STS) rescue. The area under the curve (AUC) of DDP for sufficient anticancer activities against cultured human cell lines in vitro was estimated at 240 micrograms h/ml, which was equivalent to the AUC gained by 110 mg/m2 ip DDP in the clinical studies. The cytotoxic activity of DDP was reduced by approximately 50% with 100-fold STS in the AUC in the experimental studies. However, this was achieved only in urine, and not in either the peritoneal cavity or in plasma in the clinical studies. Three cases of a partial response against peritoneal carcinomatosis were seen from a total of four evaluable cases treated with 110 mg/m2 DDP, and no renal toxicities were observed in those treated with the STS rescue. The results of this study led us to conclude that high-dose ip DDP treatment combined with the STS rescue would be useful chemotherapy against peritoneal carcinomatosis caused by gastric cancers.

A suitable model for experimental liver metastasis of human colon cancer xenografts using mice with severe combined immunodeficiency

Studies on liver metastasis of human colon cancer are limited because of a lack of suitable animal models. In this study, the usefulness of mice with severe combined immunodeficiency (SCID), which congenitally lack functional T and B lymphocytes, was evaluated in comparison with currently available nude mice. Three human colon cancer xenografts transplantable into nude mice were disaggregated enzymatically to obtain tumor cell suspensions, and implanted intrasplenically into SCID and nude mice. The incidence of splenic tumorigenesis and of liver metastases were significantly greater in SCID mice for all xenografts, in comparison with nude mice. In total, 33 of 36 SCID mice and 17 of 43 nude mice developed liver metastases. On the basis of this result, we conclude that SCID mice would be a more suitable model than nude mice for studying liver metastasis of human colon cancer.

Role of adrenergic neuronal activity in the yawning induced by tacrine and NIK-247 in rats

The present experiments were performed to investigate the potential role of central adrenergic neurons in regulating occurrence of yawning in rats. Intraperitoneal injection of tacrine (THA) or 9-amino-2,3,5,6,7,8-hexahydro-1H-cyclopenta(b)-quinoline monohydrate HCl (NIK-247), cholinesterase inhibitors, induced yawning, which was markedly increased by pretreatment with the beta-adrenoceptor antagonist, pindolol. The yawning evoked by tacrine or NIK-247 given alone or in combination with pindolol was inhibited by pretreatment with scopolamine but not by mecamylamine or spiperone. Treatment with tacrine or NIK-247 increased acetylcholine content of the striatum, but this effect was not enhanced by pindolol, which per se did not affect basal acetylcholine content. Moreover, pretreatment with the central adrenaline synthesis inhibitors, (+-)-2,3-dichloro-alpha-methylbenzylamine HCl (LY-78335) and 2-cyclooctyl-2-hydroxyethylamine HCl (UK-1187A), increased tacrine-induced yawning. Subcutaneous injection of talipexole (B-HT 920), a dopamine D2 receptor agonist, evoked yawning, which was also increased by pindolol, LY-78335, and UK-1187A. These receptors antagonists and synthesis inhibitors per se did not cause yawning responses. The results suggest that the beta-adrenoceptor blockade and the inhibition of adrenaline synthesis facilitate the occurrence of yawning induced by cholinergic and dopaminergic agonists, and thus the central adrenergic neuronal systems may be implicated in the regulation of yawning responses.

[MR imaging of stereotactic thalamotomy using radiofrequency methods]

Sixty-eight stereotactic radiofrequency (rf) thalamic lesions in 57 patients with movement disorders were evaluated by magnetic resonance (MR) imaging. Postoperative periods ranged from 5 days to 4 years and 9 months. All 68 rf lesions were clearly detected on T2-weighted images (T2WI). Changes in signal intensity on T2WI were classified into five patterns, as follows: Pattern I: lesions with three concentric zones consisting of an inner hypointense, middle hyperintense and outer hypointense zone (31 lesions); Pattern II: lesions consisting of an inner hypointense and outer hyperintense zone (4 lesions); Pattern III: lesions consisting of an inner hyperintense and outer hypointense zone (27 lesion); Pattern IV: lesions of a hyperintense area alone (2 lesions); Pattern V: lesions of a hypointense area alone (4 lesions). The outer hypointense rim in Patterns I and III is thought to represent hemosiderin deposition. The abnormal signal intensity on T2WI caused by rf ranged from 2 to 12 mm in diameter, and lesions in the late phase were smaller than lesions in the early phase.

Endothelin-1 enhances calcium entry through T-type calcium channels in cultured neonatal rat ventricular myocytes

Endothelin-1 (ET-1), a 21-amino acid vasoconstrictive peptide, increases intracellular Ca2+ level and has hypertrophic action on ventricular myocytes. To elucidate a possible role of Ca2+ entry through sarcolemmal Ca2+ channels on this ET-1 action, we examined effects of ET-1 on L-type (ICa,L) and T-type (ICa,T) Ca2+ currents in cultured neonatal rat ventricular myocytes using the patch-clamp technique. ET-1 at a concentration of 10 nM increased the maximum current density of ICa,T from -3.0 +/- 1.4 microA/cm2 in the control condition to -4.4 +/- 1.6 microA/cm2 (p < 0.01). Although the peak amplitude of ICa,L was decreased during ET-1 application (from -9.7 +/- 1.9 microA/cm2 in the control condition to -5.0 +/- 1.4 microA/cm2 [p < 0.01]), this magnitude of decrease in ICa,T (52 +/- 19%) was comparable to that of spontaneous "run-down" of ICa,L (47 +/- 26%). The enhancement of ICa,T by ET-1 was dose dependent; it was initiated as low as 0.32 nM, and the maximal response was attained at approximately 10 nM, with a half-maximal dose of 1.26 nM. The enhancement of ICa,T by ET-1 was antagonized by protein kinase C inhibitors staurosporine (0.2 microM) and 1-(5-isoquinolinesulfonyl)-2-methylpiperazine (H-7, 20 microM) applied to the pipette solution. Extracellular application of tumor-promoting phorbol esters, phorbol 12,13-dibutyrate (PDBu) and 4 beta-phorbol 12-myristate 13-acetate, augmented ICa,T. PDBu (0.2 microM) increased the maximal current density of ICa,T from -4.2 +/- 0.5 microA/cm2 in the control condition to -5.5 +/- 1.0 microA/cm2 (p < 0.01). In the presence of H-7 (20 microM) in the pipette solution, PDBu failed to enhance ICa,T, and an inactive isomer of PDBu (4 alpha-phorbol 12,13-dibutyrate, 0.2 microM) did not augment ICa,T. Thus, ET-1 enhances Ca2+ entry through the sarcolemmal T-type Ca2+ channel, possibly through a pathway involving activation of protein kinase C. This ET-1 action may be involved in the rise of the intracellular Ca2+ level and may contribute to the induction of cardiac hypertrophy by ET-1.

Exhaustive physical exercise causes oxidation of glutathione status in blood: prevention by antioxidant administration

We have studied the effect of exhaustive concentric physical exercise on glutathione redox status and the possible relationship between blood glutathione oxidation and blood lactate and pyruvate levels. Levels of oxidized glutathione (GSSG) in blood increase after exhaustive concentric physical exercise in trained humans. GSSG levels were 72% higher immediately after exercise than at rest. They returned to normal values 1 h after exercise. Blood reduced glutathione (GSH) levels did not change significantly after the exercise. We have found a linear relationship between GSSG-to-GSH and lactate-to-pyruvate ratios in human blood before, during, and after exhaustive exercise. In rats, physical exercise also caused an increase in blood GSSG levels that were 200% higher after physical exercise than at rest. GSH levels did not change significantly. Thus, both in rats and humans, exhaustive physical exercise causes a change in glutathione redox status in blood. We have also found that antioxidant administration, i.e., oral vitamin C, N-acetyl-L-cysteine, or glutathione, is effective in preventing oxidation of the blood glutathione pool after physical exercise in rats.

The mucus-hypersecreting tumor of the pancreas. Development and extension visualized by three-dimensional computerized mapping

BACKGROUND

Mucus-hypersecreting tumor of the pancreas appears as dilated ducts and cystic spaces filled with mucus. To determine where such tumors arise and how they extend, computer-aided three-dimensional reconstruction was done of the ductal system. This also was used to visualize the spatial relationships among epithelial hyperplasia, dysplasia, and carcinoma in situ (CIS).

METHODS

Surgically removed pancreases were studied from 12 patients with mucus-hypersecreting tumors. The specimens were fixed in buffered formaldehyde solution 10%, embedded in paraffin and semiserially sectioned at 3 microns at an interval of 60 microns. The ductal contours were differentiated among ducts lined by ordinary epithelia, hyperplastic epithelia, dysplastic cells, or CIS and were inputted into a computer system that integrated a three-dimensional image of ducts in the display.

RESULTS AND CONCLUSIONS

(1) The tumors arose in the main pancreatic duct or its subbranches, and the cysts corresponded to segments expanded by the superficial growth of tumor cells; (2) areas of CIS arose in zones of preceding dysplasia, suggesting a dysplasia-carcinoma sequence; and (3) dysplastic or cancerous cells often extended intraductally over the dilated segments of ducts.

In vitro purging of clonogenic leukemic cells from human bone marrow by heat: simulation experiments for autologous bone marrow transplantation

In order to apply a simple purging method by heat to autologous bone marrow transplantation (ABMT), we have revaluated the ability to purge clonogenic leukemic cells from the simulated marrow mixture of normal marrow cells and leukemic cell lines (HL-60, Molt-3 and HEL) in vitro by heat, using two different clonogenic assays for normal granulocyte-macrophage progenitors (CFU-GM) and leukemic cell lines. It appeared that in vitro hyperthermia (42 degrees C for 120 min) is able to selectively remove clonogenic leukemic cells from simulated tumor cell-normal marrow mixtures even when leukemic cell concentrations are increased up to 3 x 10(6) cells/ml in vitro, and results in a 4-6 log destruction of clonogenic leukemic cells/ml according to a limiting dilution assay, while leaving half of normal CFU-GM surviving. The hyperthermic purging of clonogenic leukemic cells was not affected in the presence of normal marrow cells in vitro. This high level of clonogenic leukemic cell depletion by heat correlated with that of immunologic and pharmacologic studies. These results suggest that in vitro hyperthermia could be applied effectively and safely for the elimination of residual clonogenic leukemic cells in autologous marrow grafts before ABMT.

Tongue cancer treated with irradiation: assessment with MR imaging

We examined the usefulness of MRI in differentiating post-radiation scar tissue from the residual tumour. Ten consecutive patients who underwent MR imaging before and after radiation therapy were assessed prospectively. T1- and T2-weighted images using a 1.5 unit were obtained in 10 patients (3 T1, 6 T2, 1 T3) at 1 week before irradiation, and 2 weeks, 2 months, 4 months, 6 months and every 6 months thereafter following completion of radiation. Although all T2 and T3 tumours demonstrated high signal intensity compared to muscle on T2-weighted images, the T1 tumour could be demonstrated in only one of three patients. Six patients in whom the primary tumour clinically disappeared demonstrated low signal intensity on T2-weighted images until 4 months after completion of radiation therapy (range 1 week to 4 months). This study suggests that MRI can detect primary tumours larger than T2 (2 cm), and may be useful in assessing the effectiveness of therapy for tongue cancer.

Ribosomal protein P2, a novel iron-binding protein

We examined the properties of a new iron-binding protein purified previously from rat liver (T. Furukawa, S. Taketani, H. Kohno, and R. Tokunaga, 1991, Biochem. Biophys. Res. Commun. 181, 409-415). The protein was digested with trypsin and the peptides were analyzed by reverse-phase high-performance liquid chromatography. The partial amino acid sequences of the tryptic peptides coincided with that of rat ribosomal protein P2. Immunoblot analysis and iron-binding assay confirmed that the iron-binding protein and ribosomal protein P2 are identical. Then the iron binding ability of ribosomal protein P2 was examined in rat hepatoma H4IIEC3 cells incubated with radioactive iron. When immunoprecipitation with anti-iron-binding protein serum was performed using cells incubated with 59Fe-citrate, about 4% of the 59Fe radioactivity in cells was associated with the iron-binding protein through 30 to 90 min of incubation. About 1.5% of radioactive iron in cells incubated with 59Fe-transferrin was found in immunoprecipitates with anti-iron-binding protein serum during 1 to 5 h of incubation, and 4 to 7% of the radioactivity was found in immunoprecipitates with a monoclonal antibody against ribosomal P proteins in the same incubation. These results demonstrate that ribosomal proteins P2 binds iron taken up by the cells.

Targeting cancer chemotherapy using a monoclonal antibody (NCC-LU-243) conjugated with mitomycin C

Two kinds of immunoconjugate (T-3M and T-11M) of murine monoclonal antibody with mitomycin C (MMC) were developed using spacers containing a disulfide (T-3M) or thiocarbamate (T-11M) bond. A murine monoclonal antibody (NCC-LU-243) raised against a human small cell lung carcinoma cell line, Lu-24, in nude mice, is an IgG2a monoclonal antibody that recognizes a 145-kDa protein on the cell surface membrane. T-3M and T-11M showed affinity for the LU-243 antigen-positive H-69 cell line but not for the antigen-negative Lu-65 cell line in vitro. In the in vitro MTT assay, the order of efficacy of these compounds was T-11M > T-3M > MMC against antigen positive H-69 and T-11M = MMC > T-3M against antigen-negative K562. When antigen-positive H-69 was transplanted into nude mice for in vivo assay, the maximum tolerated dose of T-3M was twice as high than that of the parent compound MMC. Furthermore, T-3M showed higher antitumor activity against antigen-positive H-69 than MMC conjugated with a non-specific rabbit IgG in vivo. When the maximum tolerated doses of T-3M and MMC were administered to H-69-bearing nude mice, the effect of T-3M was superior to that of MMC, whereas no differences were observed between the antitumor activity of T-3M and MMC against antigen- negative MX-1, a human breast carcinoma. These two immunoconjugates of monoclonal antibody with mitomycin C are thought to be useful for targeting cancer chemotherapy against human small cell lung carcinomas.

Atelosteogenesis type 3: the first patient in Japan and a survivor for more than 1 year

We report the first patient of atelosteogenesis type 3 (AO3) in Japan. The patient had multiple craniofacial abnormalities at birth, including ocular hypertelorism, a flat nasal bridge, micrognathia and a cleft palate. There was rhizomelic shortness of the limbs and a club-foot. The infant had short broad thumbs in the hands similar to those observed in the feet. There were no chromosomal abnormalities. Radiological examination demonstrated striking hypoplasia of the humerus with proximal rounding and distal tapering giving a 'drumstick' appearance, 'S'-shape configuration of the cervical spine, scoliosis and coronal cleft in the thoracolumbar vertebral bodies. The infant experienced recurrent apnea and persistent severe tracheomalacia, which necessitated tracheostomy at 5 months of age. Despite his multiple skeletal deformities and respiratory problems, this patient survived more than 1 year with motoneuronal developmental delay.

The mucus-hypersecreting tumor of the pancreas. Development and extension visualized by three-dimensional computerized mapping

BACKGROUND

Mucus-hypersecreting tumor of the pancreas appears as dilated ducts and cystic spaces filled with mucus. To determine where such tumors arise and how they extend, computer-aided three-dimensional reconstruction was done of the ductal system. This also was used to visualize the spatial relationships among epithelial hyperplasia, dysplasia, and carcinoma in situ (CIS).

METHODS

Surgically removed pancreases were studied from 12 patients with mucus-hypersecreting tumors. The specimens were fixed in buffered formaldehyde solution 10%, embedded in paraffin and semiserially sectioned at 3 microns at an interval of 60 microns. The ductal contours were differentiated among ducts lined by ordinary epithelia, hyperplastic epithelia, dysplastic cells, or CIS and were inputted into a computer system that integrated a three-dimensional image of ducts in the display.

RESULTS AND CONCLUSIONS

(1) The tumors arose in the main pancreatic duct or its subbranches, and the cysts corresponded to segments expanded by the superficial growth of tumor cells; (2) areas of CIS arose in zones of preceding dysplasia, suggesting a dysplasia-carcinoma sequence; and (3) dysplastic or cancerous cells often extended intraductally over the dilated segments of ducts.

Modulation by l-leucovorin of 1-hexylcarbamoyl-5-fluorouracil antitumor activity on human gastric and colon carcinomas serially transplanted into nude mice

Experimental biochemical modulation of 1-hexylcarbamoyl-5-fluorouracil (HCFU) with l-leucovorin (LV) was carried out using human gastric (H-111) and colon (Co-4) carcinoma xenografts serially transplanted into nude mice. Thirty-five or 70 mg/kg HCFU dissolved in 0.2 ml of 1% hydroxymethyl cellulose was administered po daily for 3 weeks except Sundays, and 50, 100, 200 or 300 mg/kg LV dissolved in 0.2 ml physiological saline was administered po 30 min before administration of HCFU. The biochemically modulated antitumor activity was evaluated in terms of actual tumor weight, the relative mean tumor weight and the degree of inhibition of thymidylate synthetase (TS) in the tumors at the end of the experiments, assayed according to the method of Spears et al. Although 35 mg/kg HCFU was ineffective against gastric carcinoma H-111, combination with 200 or 300 mg/kg LV resulted in a positive antitumor effect of HCFU on this strain without any increase of side effects in terms of body weight loss and mouse mortality. The colon carcinoma strain Co-4 showed marginal sensitivity to HCFU (35 mg/kg) alone, but 50 or 100 mg/kg LV modulated the antitumor activity of HCFU on Co-4 to produce a significant positive effect without any increase in toxicity, and HCFU administered with 100 mg/kg LV was more effective than the maximum tolerated dose of HCFU (70 mg/kg) alone. The TS inhibition rate was closely related to the biochemical modulation of HCFU antitumor activity by LV, suggesting that the modulation involves an increase of the ternary complex of TS, 5,10-methylene tetrahydrofolate from LV and 5-fluorodeoxyuridine 5'-monophosphate (FdUMP). Combination of HCFU and LV is therefore thought to be useful in increasing the antitumor activity of HCFU on gastrointestinal carcinomas without enhancing its toxicity.

Perceived parental rearing, personality and mental status in Japanese adolescents

As a part of a prospective study on the psychological adjustment of Japanese teenagers enrolled in a foreign exchange student program, the Parental Bonding Instrument (PBI), the Maudsley Personality Inventory and the General Health Questionnaire (GHQ) were administered to 130 females and 47 males aged 17 through 19 before departure. Parental practices were found to influence personality features, which in turn contribute to the mental health status, but no direct significant relationship was found between the PBI and GHQ measures. The last finding is in contradistinction to the previous reports which report low care and high overprotection in unipolar depressives and anxiety disorder patients but in accordance with a recent finding which failed to replicate them in general population. It is possible that the earlier findings in clinical populations were a case of Berkson bias.

Orthotopic reconstitution of human small-cell lung carcinoma after intravenous transplantation in SCID mice

We have constructed an orthotopically reconstituted model of human small-cell lung carcinoma (SCLC) by intravenous transplantation in severe combined immunodeficient (SCID) mice. Two human SCLC xenografts, H-69 and Lu-130, were disaggregated and injected through the tail vein of SCID mice. Human SCLCs were orthotopically reconstituted with multi-focal lung tumor growth in all SCID mice after intravenous injection of 5 x 10(6) tumor cells per mouse. The heart and liver were also seeded with actively growing SCLC. This orthotopic reconstitution model of human SCLC in SCID mice should be useful for further studies on the biological behavior and treatment of human SCLC.

Chemosensitivity testing of clinical gastrointestinal cancers using histoculture and the MTT end-point

Three-dimensional histoculture with the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide (MTT) end-point was utilized for chemosensitivity testing of 100 clinical gastrointestinal cancers and the results were compared with those obtained with cell-suspension culture with the MTT end-point. Of the 100 surgical specimens, 91 were evaluable using histoculture assay and 66 were evaluable using the cell-suspension assay. When the assay results were compared with historical frequency of clinical response to chemotherapy, the results of the histoculture assay showed a closer correlation than those of the cell-suspension assay. Therefore, the histoculture assay seems to have a higher evaluability rate and a closer correlation with clinical chemosensitivity of gastrointestinal cancers than the cell-suspension assay.

Biochemical and immunological characterization of the DNA binding protein (RBP-J kappa) to mouse J kappa recombination signal sequence

We have investigated whether J kappa recombination signal sequence (RS) binding protein (RBP-J kappa) has any partial catalytic activities involved in the VDJ recombination reaction, such as cleavage, ligation, and bending of DNA. Murine RBP-J kappa protein purified by J kappa-RS affinity chromatography did not show DNA cleavage activities but contained a strong DNA ligase activity. To obtain a large amount of purified RBP-J kappa protein, recombinant RBP-J kappa was synthesized in Escherichia coli as a fusion protein and also in silkworm cells. Although recombinant RBP-J kappa produced in silkworm cells could bind J kappa-RS, it failed to show either ligase or DNA bending activity. Since the DNA affinity-purified RBP-J kappa has the ligase activity, the RBP-J kappa protein may form a complex with a ligase in vivo. We have raised monoclonal antibodies against the RBP-J kappa fusion protein which was synthesized in E. coli and unable to bind J kappa-RS. Using the anti-RBP-J kappa monoclonal antibody we have shown that the RBP-J kappa protein is expressed ubiquitously in mammalian tissues. The ubiquitous expression of the RBP-J kappa protein is consistent with the hypothesis that the RBP-J kappa protein may have dual function [Furukawa et al. (1991) J. Biol. Chem. 266, 23334-23340].

Agrimoniin, an antitumor tannin of Agrimonia pilosa Ledeb., induces interleukin-1

The induction of interleukin-1 (IL-1) by agrimoniin, a tannin of Agrimonia pilosa Ledeb., in human peripheral blood mononuclear cells (PBMC) in vitro and in mouse adherent peritoneal exudate cells (PEC) in vivo was studied. A significant amount of IL-1 beta in the culture supernatant of the human PBMC stimulated with agrimoniin was detected with an enzyme-linked immunoadherent assay. Agrimoniin induced IL-1 beta secretion dose- and time-dependently. The adherent PEC from mice intraperitoneally injected with agrimoniin (10 mg/kg) also secreted IL-1 4 days later. These results suggest that agrimoniin, a plant tannin, is a novel cytokine inducer.

Characterization of the sodium current in single human atrial myocytes

Patch-clamp recording techniques have permitted measurement of the fast Na+ current (INa) in isolated cardiac cells from a number of species in recent years. However, there is still only very little information concerning human cardiac INa. The purpose of this study was to describe the kinetics of INa in normal-appearing, Ca(2+)-tolerant, enzymatically isolated human atrial myocytes using whole-cell voltage-clamp techniques. Atrial specimens were obtained from 46 patients undergoing open heart surgery. Cs+ was substituted for K+ in both pipette and external solutions and F- was added to the former. The reversal potential of the rapid inward current varied approximately 57 mV at 17 +/- 1 degrees C with a 10-fold change in [Na+]o, and the current was completely blocked by 100 microM tetrodotoxin, findings typical of the fast cardiac Na+ current. The tetrodotoxin dose-response curve was best fitted by an equation describing binding to high- and low-affinity sites. INa was activated at a voltage threshold of -70 to -60 mV, and peak inward current was obtained at approximately -30 mV (holding potential, -140 mV). The inactivation time course was voltage dependent and was fitted best by the sum of two exponentials. The relation between voltage and steady-state availability (h infinity) was sigmoidal with the half-inactivation at -95.8 +/- 0.9 mV and a slope factor of 5.3 +/- 0.1 mV (n = 46), and we did not observe a significant difference with disease and age. The overlap of the h infinity and activation curves suggested the presence of a Na+ "window" current. Recovery from inactivation also was voltage dependent and best fitted by a model describing the sum of two exponentials. Recovery occurred after an initial delay at potentials positive to -140 mV, suggesting that inactivation of human atrial INa is a multistate process. We conclude that INa of normal-appearing, Ca(2+)-tolerant human atrial myocytes is similar to that of other mammalian cardiac cells with the possible exception of having two tetrodotoxin binding sites.

[Imaging diagnosis of the insulinoma--the clinical usefulness of intraductal ultrasonography of the pancreas and color Doppler sonography]

5 cases of small-sized insulinoma of the pancreas were studied to evaluate the ability of diagnostic imaging techniques to determine tumor location. Techniques used were extracorporeal ultrasonography, endoscopic ultrasonography (EUS), angiography, percutaneous transhepatic portal catheterization and CT. EUS was superior to the other modalities in diagnosing the location of insulinomas. We employed Color Doppler (CD) ultrasonography in one case and obtained color expression in the tumor and a pulsatile wave in the FFT analysis. Intraductal sonography of the pancreas (IDSP) was also performed in this case resulting peripheral echo-lucent, central echogenic mass. From these results, we expect that CD and IDSP will be useful in clinical application for diagnosing various tumors.

Gene introduction into granulocyte-macrophage progenitor cells by electroporation: the relationship between introduction efficiency and the proportion of cells in S-phase

Our previous study demonstrated the positive relationship between the gene introduction rate into hematopoietic cell lines by electroporation and the percentage of cells in S-phase. In the present study, granulocyte-macrophage progenitor cells (CFU-C) rich marrow cell fraction were cultured in suspension with IL-3, GM-CSF and G-CSF for 4 days. The number of CFU-C were increased three times after the culture, and 3H-thymidine suicide tests of cultured cells demonstrated that the proportion of CFU-C in S-phase was increased by two to four times. The efficiency of gene transfer into CFU-C with the plasmid pMoZtk (containing the beta-galactosidase gene) by electroporation was nearly doubled by culturing marrow cells with these growth factors. These findings confirm that the introduction rate of the gene into CFU-C by electroporation is more efficient in cell populations with a higher percentage of CFU-C in S-phase.