Laser scanning cytometry (LCS) allows detailed analysis of the cell cycle in PI stained human fibroblasts (TIG-7)

We have demonstrated a method for the in situ determination of the cell cycle phases of TIG-7 fibroblasts using a laser scanning cytometer (LSC) which has not only a function equivalent to flow cytometry (FCM) but also has a capability unique in itself. LSC allows a more detailed analysis of the cell cycle in cells stained with propidium iodide (PI) than FCM. With LSC it is possible to discriminate between mitotic cells and G2 cells, between post-mitotic cells and G1 cells, and between quiescent cells and cycling cells in a PI fluorescence peak (chromatin condensation) vs. fluorescence value (DNA content) cytogram for cells stained with PI. These were amply confirmed by experiments using colcemid and adriamycin. We were able to identify at least six cell subpopulations for PI stained cells using LSC; namely G1, S, G2, M, postmitotic and quiescent cell populations. LSC analysis facilitates the monitoring of effects of drugs on the cell cycle.

Impaired left ventricular myocardial metabolism in patients with pulmonary hypertension detected by radionuclide imaging

To assess whether left ventricular myocardial metabolism is affected by the presence of right ventricular pressure overload, we performed 123I-beta-methyl-iodophenyl pentadecanoic acid (123I-BMIPP) and 99Tc(m)-sestamibi (99Tc(m)-MIBI) single photon emission tomography in 24 patients with pulmonary hypertension and in 10 control subjects. The left ventricle was divided into six regions using a short-axis tomogram at the mid-ventricular level. The relative regional uptake (RRU, %) was determined for each region as the ratio of the regional uptake per pixel to the maximum uptake in the six regions. Right heart catheterization was performed to obtain mean pulmonary arterial pressure. 123I-BMIPP uptake in the septum and the adjacent myocardium of the left ventricle was lower in patients with pulmonary hypertension than in control subjects (septal RRU, 75 +/- 6 vs 85 +/- 4%; anteroseptal RRU, 76 +/- 6 vs 86 +/- 3%; posteroseptal RRU, 75 +/- 4 vs 84 +/- 4%; P < 0.001). The reduction in 99Tc(m)-MIBI uptake was confined to the septum in patients with pulmonary hypertension (79 +/- 5 vs 85 +/- 5%; P < 0.05). Interestingly, the septal RRU of 123I-BMIPP and the sum of the septal, anteroseptal and posteroseptal RRUs of 123I-BMIPP were negatively correlated with mean pulmonary arterial pressure (r = -0.70 and -0.55, respectively; P < 0.01). In conclusion, myocardial metabolism in the interventricular septum and the adjacent regions of the left ventricle may be impaired in proportion to the degree of pulmonary hypertension.

[Wide resection and reconstruction of chest wall: usefulness of A-O metal plate]

A 53-year-old male was admitted to our department with a chest tumor due to infiltration of lung cancer. Right upper lobectomy and a wide en bloc excision of the right upper chest wall were performed, including the 2nd, 3rd, 4th, and 5th ribs with upper lobectomy of right lung. The defect was replaced with three A-O metal plates, which joined both stumps of the ribs, from the third to the fifth rib. These metal plates were very useful because it was easy to bent and twist them to fit the defect in operation. And curved metal plates preserved a cone from of chest cage. Postoperative course was favourable without mechanical ventilation and wound infection.

Quantitation of group-specific a antigen in hepatitis B vaccines by anti-HBs/a monoclonal antibody

Balb/c mice were immunized with aluminium hydroxide [alum, Al (OH)3]-adjuvanted hepatitis B (HB) vaccines of subtypes adr, ayw or adw. Spleen cells from the immune animals were fused with SP2/O cells. Eight hybridoma clones producing antibodies specific for HB surface antigen (HBsAg) were selected. Monoclonal antibodies (mAbs) of four clones were specific for group-specific antigen/a, and the other of four clones were specific for subtype antigen/d, y, r, or w. The anti-HBs/a mAbs were classified into three non-competitive groups. Quantitation of group-specific determinant a of HBsAg (HBsAg/a) was performed by sandwich enzyme-linked immunosorbent assay (ELISA), in which a solid phase of anti-HBs guinea-pig polyclonal antibodies (pAb), the HBsAg for testing, anti-HBs/a mouse mAb and horseradish peroxidase (HRP)-conjugated anti-mouse IgG were used. The unadsorbed HBsAg was used to establish the standard curve of HBsAg/a. The lower detection limits were 0.5 to 1 ng/ml of HBsAg. Methods of solubilization of alum were investigated to quantify HBsAg/a in adsorbed HB vaccines. The recovery rate was more than 60% if vaccines were prediluted. The recovery of HBsAg/a in HB vaccines produced by the same manufacturer showed the similar recovery rate, and the contents of HBsAg/a in adsorbed HB vaccines could be estimated by the recovery rate determined for adsorbed HB vaccines.

A novel transcript for the thyrotropin-releasing hormone receptor in human pituitary and pituitary tumors

We measured the amounts of TRH receptor (TRHR) messenger ribonucleic acid (mRNA) in human normal pituitary and pituitary tumors and found a novel transcript of the TRHR gene. Competitive PCR revealed expression of the TRHR mRNA in all pituitary adenomas examined, and its level was variable and similar to that in the normal pituitary. When the C-terminal region was amplified by PCR, an additional short product was observed. Cloning and sequence analysis of this short fragment revealed that the deleted sequence corresponded exactly to the 5'-sequence of exon 3, indicating alternative splicing of the TRHR mRNA. This alternative splicing resulted in a frame shift, yielding a C-terminal truncated protein (HTRHR2) on translation. Expression analysis of HTRHR2 in Chinese hamster ovary cells showed no significant binding to [3HIMeTRH or response of intracellular calcium to TRH administration. However, the mRNA ratio of HTRHR2 vs. the wild type (HTRHR1) was significantly different among pituitary tumors. The highest ratio was observed in prolactinomas (30%), and almost no detectable expression was found in GH-producing tumors. These findings indicate that this novel transcript of the human TRH receptor gene is produced in a tumor-specific manner and may be a useful parameter for evaluation of individual pituitary tumors.

Immunohistochemical and structural characteristics of the reticular framework of the white pulp and marginal zone in the human spleen

BACKGROUND

The reticular framework of the white pulp (WP) and marginal zone (MZ) consists of reticulum cells and reticulin fibers. The antigenic heterogeneity of the reticular framework is well documented in the mouse and rat spleen. The aim of the present study is to characterize the reticular framework of the WP and MZ of the human spleen.

METHODS

Nine surgically resected human spleens were investigated. Five of the nine spleens were perfused. Formalin-fixed materials were embedded in paraffin and serial sections prepared for hematoxylin-eosin, silver staining, and immunohistochemical examination. Electron and immuno-electron microscopy were also applied. Using confocal laser scanning microscopy, the reticular framework was analyzed three-dimensionally.

RESULTS

The reticulin fibers of the framework were immunostained for type IV collagen in the WP and MZ. The WP was three-dimensionally delimited by the alpha-smooth muscle actin (alpha-SMA)-positive reticulum cells. In the WP, the distribution of alpha-SMA-positive reticulum cells formed the reticular framework of the periarteriolar lymphoid sheath (PALS). They also ensheathed the reticulin fibers. Interdigitating cells (IDCs) were scattered throughout the framework. A few IDCs attached to the framework. In the lymph follicle (LF), reticulum cells were not alpha-SMA-positive. The mesh of follicular dendritic cells (FDCs) was found in the germinal center. In places, the reticulin fibers were involved in the mesh of the FDCs and covered by the cytoplasm of FDCs. In the MZ, alpha-SMA-positive reticulum cells were arranged in a mesh pattern and ensheathed the fine reticulin fibers.

CONCLUSION

The reticular framework of the PALS, LF, and MZ is specialized into heterogeneous components in the human spleen. The heterogeneity of the framework may induce the segregation of T and B lymphocytes.

Metallothionein expression and concentrations of copper and zinc are associated with tumor differentiation in hepatocellular carcinoma

Metallothionein is the carrier protein of heavy metal ions, such as copper (Cu) and zinc (Zn). In this study, the relationships among immunohistochemical expression of metallothionein, concentrations of Cu and Zn, histological differentiation and proliferative activity of hepatocellular carcinoma were investigated in 51 cases. The concentrations of Cu and Zn in both tumor and non-tumor tissues were determined using electron probe microanalysis. Immunohistochemical expression of metallothionein in tumor tissues decreased with the degree of differentiation, whereas the number of hepatocytes positive for Ki-67 increased. Furthermore, the concentrations of Cu and Zn in tumor tissues decreased with the degree of histological differentiation in human hepatocellular carcinoma.

[Epidural midazolam attenuates renal sympathetic nerve activity in rabbits]

The effects of epidural midazolam on heart rate (HR), mean arterial pressure (MAP) and the renal sympathetic nerve activity (RSNA) were examined. Under alpha-choloralose anesthesia, 31 male Japanese-white rabbits received epidural catheterization and surgical procedures for measurement of the renal sympathetic nerve activity. Epidural low (0.05%) and high (0.5%) concentrations of midazolam did not affect HR, but significantly decreased MAP and RSNA-spikes (the spike count of RSNA). Intravenous flumazenil significantly increased MAP and RSNA-spikes. These findings suggest that the decrease in RSNA-spikes induced by epidural midazolam is derived from the benzodiazepine receptor. Intramuscular midazolam (0.5%) did not affect HR, but decreased MAP and RSNA-spikes significantly. In the spinal cord dissected rabbits, epidural midazolam (0.5%) did not affect HR and MAP, but significantly attenuated RSNA-spikes. In conclusion, epidural midazolam attenuated RSNA through the benzodiazepine receptors of both the spinal and supraspinal nervous system.

The relationship between primary splenic malignant lymphoma and chronic liver disease associated with hepatitis C virus infection

BACKGROUND

An etiologically important role has been suggested for hepatitis C virus (HCV) infection in the development of B-cell non-Hodgkin's lymphoma (NHL). HCV has been recognized as the major cause of non-A, non-B chronic hepatitis throughout the world. Moreover, the occurrence of primary splenic malignant lymphoma (PSML) has been demonstrated in patients with chronic liver disease.

METHODS

In this study, the authors describe three patients with PSML. The clinical, histologic, and immunohistochemical features of the lymphomas were studied. Clonal immunoglobulin heavy chain gene rearrangement was investigated by polymerase chain reaction.

RESULTS

All three cases of PSML were detected by imaging studies performed in routine follow-up of cases of chronic liver disease associated with HCV infection. Macronodular lesions were found in the three spleens; two of them were of normal weight and another was moderately enlarged. The former two were the smallest PSMLs reported to date. The histology was B-cell NHL in all cases. All 3 patients were alive after splenectomy with an average follow-up of 51.7 months (range, 35-74 months).

CONCLUSIONS

HCV infection may play an etiologic role in the development of splenic B-cell lymphoma. The long survival of the patients in this study may have been due to early splenectomy.

The relationship between primary splenic malignant lymphoma and chronic liver disease associated with hepatitis C virus infection

BACKGROUND

An etiologically important role has been suggested for hepatitis C virus (HCV) infection in the development of B-cell non-Hodgkin's lymphoma (NHL). HCV has been recognized as the major cause of non-A, non-B chronic hepatitis throughout the world. Moreover, the occurrence of primary splenic malignant lymphoma (PSML) has been demonstrated in patients with chronic liver disease.

METHODS

In this study, the authors describe three patients with PSML. The clinical, histologic, and immunohistochemical features of the lymphomas were studied. Clonal immunoglobulin heavy chain gene rearrangement was investigated by polymerase chain reaction.

RESULTS

All three cases of PSML were detected by imaging studies performed in routine follow-up of cases of chronic liver disease associated with HCV infection. Macronodular lesions were found in the three spleens; two of them were of normal weight and another was moderately enlarged. The former two were the smallest PSMLs reported to date. The histology was B-cell NHL in all cases. All 3 patients were alive after splenectomy with an average follow-up of 51.7 months (range, 35-74 months).

CONCLUSIONS

HCV infection may play an etiologic role in the development of splenic B-cell lymphoma. The long survival of the patients in this study may have been due to early splenectomy.

[The effects of high-dose ifosfamide in the treatment of bone and soft tissue sarcomas]

From January 1990 to December 1995 we treated 35 patients (pts) with bone and soft tissue sarcoma with ifosfamide (IFM). Sixteen patients had measurable metastatic pulmonary lesion and 9 had primary lesion. Histology of the tumor included osteosarcoma in 13 pts, Ewing sarcoma in 5 pts, malignant fibrous histiocytoma of bone in 2 pts, synovial sarcoma in 7pts, primitive neuroectodermal tumor in 2 pts, and other in 7 pts. The IFM at the dose of 12-18g/m2 (mean 15. 4g/m2) for 5 to 8 days continuous infusion was administered to patients in each treatment course. The uroprotector, mesna, was also given concomitantly in 60-100% dose of IFM. Eighteen pts received one course of IFM treatment. Other pts received 2 to 8 courses of IFM treatment at three to four week intervals. The overall response rate was 40% (PR in 14 pts, NC in 18 pts, and PD in 3 pts). The response rate of 13 pts with osteosarcoma was 54% (PR in 7 pts) and 30% in 15 pts with soft tissue sarcoma (PR in 5 pts).

The primary structure and distribution of killifish visual pigments

Five cDNA fragments (KFH-R, -V, -G, -B and -Rh) encoding the putative visual pigments of killifish were isolated and sequenced. Judging from the deduced amino acid sequences, each cDNA falls into a different group of the five major families of vertebrate visual pigment genes. In situ hybridization localized the mRNA of KFH-R and -G to the principle and accessory members, respectively, of double cones. Visual pigment genes KFH-Rh, -B and -V were expressed in the rods, and the long and short single cones, respectively. It is suggested that the relationships between the cell types and their respective visual pigment gene groups may be a common pattern among teleost fishes.

Viable but denervated right ventricular myocardium: a case of Eisenmenger reaction

We report on a 47-year-old woman who experienced an Eisenmenger reaction (mean pulmonary artery pressure: 86 mm Hg) induced by atrial septal defect. Radionuclide myocardial scans with 99mTc-MIBI and 123I-BMIPP showed increased uptake to the right ventricular myocardium, whereas the 123I-MIBG scan disclosed no uptake to the right ventricular myocardium. The scans showed no apparent abnormality in the left ventricular myocardium. These findings suggest that the right ventricular myocardium was viable but denervated due to severe pulmonary hypertension. The mechanism of right ventricular failure may be closely related to sympathetic denervation.

Overexpression in Escherichia coli of chemically synthesized gene for active 0.19 alpha-amylase inhibitor from wheat kernel

A synthetic gene encoding 0.19 alpha-amylase inhibitor (alpha-AI) from wheat kernel was obtained by enzymatic assembly of 18 oligodeoxynucleotides which were chemically synthesized. The synthetic gene was introduced into vector pET15b for expression in Escherichia coli BL21(DE3) under the control of T7 promoter. However, in SDS-PAGE and Western blotting analyses of the E. coli cell lysate, the expression product could not be detected. Expression analysis for various partially deleted gene fragments suggested that the putative hairpin-like structure of mRNA in the 5'-terminal coding region might interrupt efficient expression. When the hairpin structure was eliminated by using degenerate codons, the resulting gene could be overexpressed in E. coli. Although the gene product was accumulated in an insoluble fraction as inclusion bodies, its inhibitory activity could be recovered by solubilization with 8 M urea, followed by refolding through two successive steps of dialysis at alkaline pH. After purification, the recombinant 0.19 alpha-AI showed the same characteristics as the authentic inhibitor in terms of N-terminal amino acid sequence, peptide mapping on reverse-phase HPLC, far-UV circular dichroism (CD) spectrum and have inhibition of human salivary alpha-amylase. Thus, we have established an overexpression system in E. coli for active recombinant 0.19 alpha-AI.

Regulation of the human TRH (hTRH) gene by human thyroid hormone receptor beta 1 (hTR beta 1) mutants

TRH is negatively regulated by T3 both in the hypothalamic paraventricular nucleus and transient transfection models. Mutations in hTR beta 1 genes are associated with the syndrome of generalized resistance to thyroid hormone. To investigate potential effects of mutant TRs on T3 regulation of the hTRH gene, transient gene expression assays were performed in human neuroblastoma (HTB-11) cells with an hTRH promoter-luciferase construct, wild type (WT) hTR beta 1, and three qualitatively distinct hTR beta 1 mutant forms (ED, OK and PV). In the presence of T3 (10(-9) M), liganded WT-hTR beta 1 inhibited hTRH promoter activity significantly (40%). Cotransfection of each of the two mutants (ED and OK) achieved similar levels of inhibition only at 10 to 100 fold increased T3 concentrations. Of interest, a 10x excess of mutant ED or OK could also exert dominant negative effects upon WT hTR beta 1-T3 mediated inhibitory actions on the hTRH promoter. In contrast, mutant TR-PV exerted neither inhibitory nor dominant negative effects at even higher concentrations of T3. Moreover, all three unliganded mutant forms stimulated TRH promoter activity significantly in the absence of T3, despite their different mutations in the ligand-binding domain (LBD). These data demonstrate that thyroid hormone resistance at the level of TRH gene regulation, due to reduced inhibitory actions of mutant TR-T3 complexes, as well as dominant negative effects upon WT hTR beta 1 mediated inhibition, likely contribute to elevated TSH values observed in the syndrome of thyroid hormone resistance.

Changes in mitochondrial membrane potential during oxidative stress-induced apoptosis in PC12 cells

We examined the effects of various types of oxidative stress on cell survival and on mitochondrial membrane potential (delta psi m) in PC12 cells transfected with BCL-2. Several types of oxidative stress such as exposure to hydrogen peroxide, 13-L-hydroperoxylinoleic acid, and xanthine + xanthine oxidase triggered apoptotic nuclear condensation and DNA fragmentation in normal PC12 cells. These types of oxidative stress induced significant increases in level of reactive oxygen species (ROS) before cell death. By contrast, BCL-2 prevented the apoptosis induced by these oxidative stresses. However, BCL-2 did not reduce ROS levels, indicating that it functions downstream of ROS generation. We measured delta psi m as a potential target of ROS during oxidative stress-induced cell death. Hydrogen peroxide, 13-L-hydroperoxylinoleic acid, and xanthine + xanthine oxidase induced a significant loss of delta psi m simultaneously with cell death. BCL-2 prevented the decrease in delta psi m as well as apoptosis induced by oxidative stress. These observations suggest that the oxidative stress triggers apoptosis associated with both increased generation of ROS and decreases in level of delta psi m and that BCL-2 prevents cell death as well as delta psi m but not ROS production.

Performance evaluation of a large axial field-of-view PET scanner: SET-2400W

The SET-2400W is a newly designed whole-body PET scanner with a large axial field of view (20 cm). Its physical performance was investigated and evaluated. The scanner consists of four rings of 112 BGO detector units (22.8 mm in-plane x 50 mm axial x 30 mm depth). Each detector unit has a 6 (in-plane) x 8 (axial) matrix of BGO crystals coupled to two dual photomultiplier tubes. They are arranged in 32 rings giving 63 two-dimensional image planes. Sensitivity for a 20-cm cylindrical phantom was 6.1 kcps/kBq/ml (224 kcps/microCi/ml) in the 2D clinical mode, and to 48.6 kcps/kBq/ml (1.8 Mcps/microCi/ml) in the 3D mode after scatter correction. In-plane spatial resolution was 3.9 mm FWHM at the center of the field-of-view, and 4.4 mm FWHM tangentially, and 5.4 mm FWHM radially at 100 mm from the center. Average axial resolution was 4.5 mm FWHM at the center and 5.8 mm FWHM at a radial position 100 mm from the center. Average scatter fraction was 8% for the 2D mode and 40% for the 3D mode. The maximum count rate was 230 kcps in the 2D mode and 350 kcps in the 3D mode. Clinical images demonstrate the utility of an enlarged axial field-of-view scanner in brain study and whole-body PET imaging.

Polypoid adenomyoma of the gallbladder

We describe a distinctive polypoid lesion of the gallbladder (16 mm in diameter) at the fundus, associated with a granulomatous mass in the liver adjacent to the gallbladder fossa, in a 64-year-old Japanese woman. Preoperatively, the lesion was diagnosed as advanced gallbladder cancer infiltrating the liver, and hepatopancreato-duodenectomy was performed. In the resected specimen, the polyp was round and pedunculate in shape, and, microscopically, it consisted of a mixture of small glandular and surrounding muscular elements, but atypia was not noted. The constituent elements were identical with those of adenomyoma, but the polypoid appearance was unusual. The hepatic lesion proved to be a foreign body granuloma containing multiple barium fragments and giant cells. A deep gastric ulcer, which penetrated into the gallbladder fossa, was also noted, near the granuloma. The histologic features indicate that the polypoid appearance of the tumor was due to a secondary modification of pre-existing adenomyoma by hepatic granuloma. To our knowledge, this is the second reported case of an adenomyomatous lesion of the gallbladder with a polypoid appearance.

Subcortical hypoperfusion associated with asymptomatic white matter lesions on magnetic resonance imaging

BACKGROUND AND PURPOSE

We examined whether hemodynamic and metabolic abnormalities in the cerebral white matter, basal ganglia, and thalamus are associated with asymptomatic white matter lesions (WML) depicted on MR images.

METHODS

A positron emission tomographic study with H2(15)O, C15O, and 15O2 was performed in eight normal control subjects without any WML (mean +/- 1 SD age, 68.5 +/- 10.2 years) and in 15 asymptomatic subjects with WML (71.3 +/- 8.5 years) to measure regional cerebral blood flow (CBF), cerebral blood volume, oxygen extraction fraction (OEF), and oxygen metabolic rate.

RESULTS

In the cerebral white matter in the asymptomatic subjects with WML, significantly lower CBF (20.3 +/- 3.9 mL/100 mL per minute; P < .05) and significantly higher OEF (0.43 +/- 0.08; P < .05) were found compared with those for control subjects (23.5 +/- 2.6 mL/100 mL per minute and 0.37 +/- 0.06, respectively). The severity of WML was not related to the magnitude of hypoperfusion. In the basal ganglia, significantly lower CBF (44.9 +/- 6.9 mL/100 mL per minute; P < .01) and significantly higher OEF (0.54 +/- 0.08; P < .01) were found in the WML group than in control subjects (70.1 +/- 12.0 mL/100 mL/min and 0.39 +/- 0.03, respectively). In the thalamus, there was no significant difference in CBF and OEF between the control and WML groups.

CONCLUSIONS

Hypoperfusion of the cerebral white matter and basal ganglia in asymptomatic WML subjects may be induced by the arteriosclerosis of long penetrating medullary arteries and lenticulostriate arteries but may not be directly related to the production of WML. The role of hypoperfusion in the production of WML and acceleration of its development remains to be elucidated.

Tertiary hypothyroidism and hyperglycemia in mice with targeted disruption of the thyrotropin-releasing hormone gene

Thyrotropin-releasing hormone (TRH) is a brain hypothalamic hormone that regulates thyrotropin (TSH) secretion from the anterior pituitary and is ubiquitously distributed throughout the brain and other tissues including pancreas. To facilitate studies into the role of endogenous TRH, we have used homologous recombination to generate mice that lack TRH. These TRH-/- mice are viable, fertile, and exhibit normal development. However, they showed obvious hypothyroidism with characteristic elevation of serum TSH level and diminished TSH biological activity. Their anterior pituitaries exhibited an apparent decrease in TSH immunopositive cells that was not due to hypothyroidism. Furthermore, this decrease could be reversed by TRH, but not thyroid hormone replacement, suggesting a direct involvement of TRH in the regulation of thyrotrophs. The TRH-/- mice also exhibited hyperglycemia, which was accompanied by impaired insulin secretion in response to glucose. These findings indicate that TRH-/- mice provide a model of exploiting tertiary hypothyroidism, and that TRH gene abnormalities cause disturbance of insulin secretion resulting in marked hyperglycemia.

Radiofrequency catheter ablation for AV nodal reentrant tachycardia associated with persistent left superior vena cava

Slow AV nodal pathway ablation using RF is highly effective for patients with refractory AV nodal reentrant tachycardia (AVNRT). We report three catheter ablation cases using RF current in patients associated with persistent left superior vena cava (PLSVC). Three patients with drug refractory AVNRT of common variety were involved in this study. An electrode catheter introduced through the left subclavian vein inserted directly into the coronary sinus, a typical anatomical finding of PLSVC. The ablation procedure was initially performed at the posteroinferior region of Koch's triangle. A slow pathway potential could not be found from that area; nonsustained junctional tachycardia (NSJT) did not occur during the delivery of RF current; there was failure to eliminate slow AV nodal pathway conduction. The catheter then was moved into the bed of the proximal portion of the markedly enlarged coronary sinus. A slow AV nodal pathway potential was recorded through the ablation catheter, and the delivery of RF current caused NSJT in two patients. Complete elimination of slow AV nodal pathway conduction was accomplished in these two patients by this method. No adverse effects were provoked by this procedure. Catheter ablation of the slow AV nodal pathway guided by a slow pathway potential and the appearance of NSJT was feasible and safe in the area of the coronary sinus ostium in patients associated with PLSVC.

Isolation from fetal bovine serum of a fragment b of complement factor B-like protein improving a long-term survival of human endothelial cells

It is known that serum is a most important factor supporting cell survival and growth. Particularly, the deprivation of serum would result in the death of human endothelial cell. Our previous paper reported an endothelial cell-viability maintaining factor (EC-VMFa) purified from fetal bovine serum and identified as an apolipoprotein. In the present further study, it is demonstrated that another potent serum factor (refer as EC-VMFb) is also possessed of the endothelial cell-viability maintaining activity, improving a long-term survival of human endothelial cells in serum-free medium. EC-VMFb has a molecular weight of 66,000 (reduced and nonreduced), pI of 4.5 and has been identified as fragment b of complement factor B (Bb)-like protein by amino-terminal amino acid sequence.

Effects of mechanical stimulation in measurement of thermal pain threshold

The improved thermal dolorimeter developed by Fukumoto has made it easy to measure thermal pain thresholds, but mechanical stimulations may be included as the probe is pressed into the skin. In order to evaluate these effects of mechanical stimulation on the improved thermal dolorimeter, the pain threshold temperatures were measured by a probe pressed to the human skin surface with weighting loads from 0.5 to 2.5 kgf. The loads of 2.0-2.5 kgf felt invasive to 8 of the 12 subjects, i.e., they experienced pain and numbness. The threshold temperature of one of these subjects, who developed water blisters around load-added area on the skin after the experiments, exceeded 50 degrees C. The result that no significant difference could be found among the thresholds at the loads of over 2.0 kgf suggests the load of less than 2.0 kgf should be kept to execute proper experiments. In order to investigate other effects on thermal property by compressing, the blood flow was measured when the skin was compressed and three dimensional heat transfer simulations were conducted. The results of the simulations demonstrated that the temperatures of the heat source which were measurable in practice differed approximately 1 to 2 degrees C from the true thresholds. The velocity of heating is also increased and subjects will be given stronger feelings of heating.