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Biomedical subjects

H Abe

Publications and source records attributed to H Abe.

At least 739 records · Page 41Linked to original sources
PubMed1994

Antiproliferative effect of tumor necrosis factor-alpha on human glioblastoma cells linked with cell cycle arrest in G1 phase.

The effects of tumor necrosis factor-alpha (TNF) on proliferation and cell cycle alterations in human malignant glioma cell lines, SF-188 and LN-382, were investigated by flow cytometry with the bromodeoxyuridine-propidium iodide dual staining technique. Low concentrations of TNF (1-100 U/ml) suppressed the growth of SF-188 assessed by cell count, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay, and thymidine incorporation assay, but not that of LN-382. After TNF treatment, the percentage of SF-188 cells in the G0/G1 phase increased, while the percentage of cells in the S phase decreased. LN-382 cells did not show any marked change in cell kinetics. TNF arrests certain human glioma cells in the G0/G1 phase resulting in reduction of deoxyribonucleic acid synthesis in the subsequent S phase, suppressing the proliferation pathway.

Brain Neoplasms↗
PubMed1994

In vivo proton magnetic resonance spectroscopy for metabolic changes of human brain edema.

The metabolism of the brain was investigated in eight patients with peritumoral edema, six patients with ischemic stroke, and 28 normal controls using proton magnetic resonance (MR) spectroscopy. The MR studies were performed using a 1.5-T whole-body imaging and spectroscopy system with a 1500-msec repetition time (TR) and a 270-msec echo time (TE). The peak areas for N-acetyl-aspartate (NAA), choline-containing compounds (Cho), creatine and phosphocreatine (Cr), and lactate (Lac) were measured, and the NAA/Cr, Cho/Cr, and Lac/Cr ratios were calculated. To quantify and compare the serial spectra, relaxation effects were investigated by acquisitions at two different points (TRs or TEs) and by monoexponential fitting. The normal NAA/Cr and Cho/Cr ratios were 2.76 and 1.09, respectively. Lac could not be identified in normal brains. In ischemic stroke and peritumoral edema, significantly increased Lac/Cr and decreased NAA/Cr ratios were observed. Resolution of peritumoral edema was associated with normalized NAA/Cr ratio and disappearance of Lac. The T1 relaxation times of the metabolites were similar in normal brain and peritumoral edema, but the T2 values were significantly shortened. Serial measurements of T2 values in two patients with peritumoral edema showed gradual normalization corresponding to improvement of the edema. To absolutely quantify metabolite concentrations in edema, changes in relaxation times should be considered.

Adult↗
PubMed1994

Efficacy of interferon therapy in patients with chronic hepatitis C. Comparison between non-drinkers and drinkers.

BACKGROUND: Alcohol has been reported to be an important factor that modulates the development and prognosis of chronic viral hepatitis; however, little is known about interaction of alcohol intake and chronic hepatitis C. The aim of this study was to examine whether alcohol drinking affects the effectiveness of interferon (IFN) therapy for chronic hepatitis C. METHODS: Thirty-nine patients with chronic hepatitis C were divided into three groups on the basis of the amount of alcohol intake before IFN therapy: group I (n = 15), non-drinkers; group II (n = 14), less than 70 g/day; and group III (n = 10), more than 70 g/day of ethanol intake for at least 10 years. The IFN (total dose, 330 +/- 206 MU) was administered daily for 2 weeks and then intermittently. Drinkers stayed abstinent for at least 1 month before, during, and after IFN therapy. The sustained responder was defined as the patient who showed normal alanine aminotransferase (ALAT) levels continuously for more than 6 months after the therapy. The liver histology (HAI score) and serum hepatitis C virus (HCV) RNA were also examined before and after the therapy. RESULTS: There was no significant difference among the three groups in the level of ALAT before IFN therapy, age, total dose of IFN, and liver histology. The rates of sustained responders in groups I, II, and III were 53.3%, 42.9%, and 0%, respectively, resulting in a significantly lower rate in group III than in groups I (p < 0.01) and II (p < 0.01). The serum HCV-RNA turned negative after the therapy in 58.3%, 20.0%, and 12.5% of groups I, II, and III, respectively, leading to a significantly lower rate of disappearance of HCV-RNA in group III than in group I (p < 0.05). CONCLUSION: The IFN therapy for chronic hepatitis C was less effective in heavy drinkers than in non-drinkers.

Alanine Transaminase↗
PubMed1994

The collagen fibrillar network in the human pial septa.

The three-dimensional organization of the collagen fibrils in the human pial septa was studied by transmission electron microscopy and by scanning electron microscopy after cell maceration with sodium hydroxide. The collagen fibrils along the nerve fibers were loosely distributed thin filaments with a diameter ranging from 25 to 40 nm (mean, 32 +/- 6 nm). Most fibrils were oriented perpendicularly to the long axis of the nerve fiber. In the deeper stroma of the pial septa, collagen fibrils were well packed and the diameter was 40 +/- 6 nm (range, 35 to 50 nm). The scanning electron microscopic study demonstrated a smooth, fabric-like structure formed by wavy and loosely interwoven thin collagen fibrils. Under high magnification, multiple collagenous sheets were observed in the pial septa by scanning electron microscopy. In addition to the structure of loosely arranged thin fibrils on the surface layer adjacent to the nerve fibers, two distinct patterns of collagen fibril network were demonstrated in the deeper stroma. One exhibited fibrils with random distribution, and the other showed well-packed, undirectionally oriented collagen. Small openings corresponding to elastic tissues were also observed. This collagen architecture may contribute to the flexibility and tensile strength of the pial septa required in the intraorbital portion of the optic nerve.

Adult↗
PubMed1994

Experimental model of posttraumatic syringomyelia: the role of adhesive arachnoiditis in syrinx formation.

An experimental model was devised to elucidate the role of spinal blockade in posttraumatic syringomyelia. Thirty-eight Japanese White rabbits, each weighing about 3 kg, were used in this study. The animals were divided into four groups: in Group 1, eight animals received traumatic injury only; in Group 2, 12 animals received traumatic injury following injection of 100 mg kaolin suspended in 1 cc normal saline solution into the subarachnoid space at the site of trauma; in Group 3, nine animals received traumatic injury following injection of 200 mg kaolin in 1 cc normal saline solution into the subarachnoid space at the site of trauma; and in Group 4, nine animals without traumatic injury received an injection of 200 mg kaolin in 1 cc normal saline solution into the subarachnoid space. The subjective criteria for syrinx formation were the presence of a definite round cyst having a smooth margin and an upper or lower extension of more than 2 cm from the injured site. Syrinx formation was seen in 12.5% (one of eight rabbits) in Group 1, 41.7% (five of 12 animals) in Group 2, 55.5% (five of nine rabbits) in Group 3 and 0% (none of nine animals) in Group 4 (p < 0.05). There was a tendency for the combined trauma/kaolin injection groups to be more prone to develop a syrinx. In the kaolin injection only group (Group 4), no animal showed a definite cyst or an extending cavity during the experimental period. The results suggest that kaolin enhances the extension of multiple small cavities that have already formed at the time of initial injury. The difference between the frequency of syrinx formation and the time of survival was statistically significant well beyond the 0.05% level. The overall difference, relating to the frequency of syrinx development, group, and duration of survival, was also statistically significant. In summary, subarachnoid block secondary to adhesive arachnoiditis is important in initiating the extension of the syringomyelia cavity.

Animals↗
PubMed1994

Regulation of the growth hormone (GH) receptor and GH-binding protein mRNA.

In fasting rats, a transient increase in growth hormone-binding protein (GHBP) mRNA levels was observed after 1 day, in muscle, heart, and liver, but not in fat tissues. The liver GH receptor (GHR) mRNA level was significantly increased after 1 day (but not after 5 days) of bovine GH (bGH) treatment in fed rats. Both the liver GHR mRNA level and the net increment of plasma IGF-I markedly decreased after 5 days of bGH administration in fasting rats. These findings suggest that GHR and GHBP mRNAs in the liver are expressed in a different way and that the expression of GHBP mRNA is regulated differently between tissues, at least in rats. The results also suggest that refractoriness to GH in a sustained fasting state might be beneficial in preventing anabolic effects of GH. In humans, GHR mRNA in lymphocytes, from subjects with either GH-deficiency or acromegaly, could be detected by the reverse transcription-polymerase chain reaction method. In one patient with partial GH insensitivity, a heterozygous missense mutation (P561T) was identified in the cytoplasmic domain of GHR.

Animals↗
PubMed1994

[Sealing effect of fibrin glue spray on protection of cerebrospinal fluid leakage through the dura mata].

Fibrin glue, a biologic adhesive, is made with highly concentrated human fibrinogen and clotting factors. It has become used frequently in neurosurgical procedures, in particular in the closure of the dura mata to prevent cerebrospinal fluid leakage. This report evaluates sealing effects of the fibrin glue on cerebrospinal fluid leakage through the dura. (1) Three manipulations for application of fibrin glue were used; i.e., layer, mixture and spray methods. These methods were compared to estimate their sealing effects on water leakage through a 1.2mm pore in an artificial dura. The burst pressure was significantly higher when the spray method was used than when the other two methods were used. (2) Dural incision was made and then sutured at intervals of 2mm, 3mm, 4mm, 6mm, and 8mm. Fibrin glue was applied by a spray method on the sutured dura. The burst pressure of the fibrin plate was over 80cmH2O on every interval of dural suture. (3) Dural defects 2mm, 4mm, 6mm, and 8mm in diameter were made, and then spray of fibrin glue was used to shield the defects. The fibrin clot spreading to the inner and outer surfaces of the pore defect was plug-shaped. The fibrin plug tolerated water pressure over 200cmH2O, in every size of pore. In conclusion, the optimal method for using fibrin glue on the surface of the dura was a spray method. Fibrin plate/clot made by the spray method sealed the dural tear or pore so well that it sustained a water pressure of over 80cmH2O, which is far higher than normal pressure of the intracranial cerebrospinal fluid.

Cerebrospinal Fluid Rhinorrhea↗
PubMed1994

[Left heart bypass with the bio-medicus centrifugal pump by the use of an antithrombin agent, argatroban].

Seventeen adult patients who underwent surgery for the thoracic or thoracoabdominal aortic disease by the use of left heart bypass with the Bio-Pump were divided into untreated, low-dose heparin treated and argatroban treated groups so as to evaluate the effects of systemic infusion of a newly synthesized antithrombin agent, argatroban, for the prevention of platelet loss and consumption coagulopathy. ACT reached 150 to 250 seconds at doses 0.5-7.5 micrograms/kg/min of argatroban and maximum ACT prolongation was limited to around 250 seconds. ACT spontaneously recovered below 150 seconds within 60 minutes following the end of bypass during which no excessive blood loss developed. In argartoban group, platelet loss during and immediately after surgery was effectively prevented as compared to other groups with significance. Fibrinogen was also preserved to some extent by argatroban treatment without evidence of systemic embolization. Argatroban, as an antithrombotic agent, is worthy of further trial of clinical use in bypass with a centrifugal pump.

Adult↗
PubMed1994

Acetazolamide challenge for three-dimensional time-of-flight MR angiography of the brain.

PURPOSE: We compared three-dimensional time-of-flight MR angiograms obtained before and after acetazolamide administration to evaluate whether use of this drug could improve visualization of small peripheral intracranial arteries and atherosclerotic stenosis. METHODS: For evaluation of small peripheral arteries, 10 patients with clinical diagnosis of ischemic cerebrovascular disease and 10 healthy volunteers were investigated, and for evaluation of stenosis, another 6 patients were investigated. Vascular images were obtained by three-dimensional time-of-flight MR angiography. After a baseline scan, 17 mg/kg acetazolamide was injected intravenously and the second scan was performed 20 minutes later. RESULTS: Several small peripheral arteries that had not been seen on the baseline images were visible on the acetazolamide images without any augmentation of the background signals. Stenotic lesions in the main trunks of the major cerebral arteries were detected more clearly on acetazolamide images. CONCLUSIONS: Acetazolamide improves visualization of small peripheral intracranial arteries and sensitivity in detecting atherosclerotic stenosis in the main trunk of major cerebral artery by three-dimensional time-of-flight MR angiography without changing MR apparatus and software.

Acetazolamide↗
PubMed1994

[Prevention of coronary spasm during and shortly after coronary revascularization in patients with variant angina].

From June 1990 to March 1993, 9 patients undergoing coronary artery bypass grafting (CABG), 4.4% of all CABG cases at our hospital during this period, had significant perioperative coronary spasm. For 4 patients who underwent CABG before May 1992 (Group 1), preventive and suppressive procedures for the coronary spasm were the addition of diltiazem in the cardioplegic solution and the continuous intravenous infusion of nitroglycerin. Perioperative myocardial infarction (PMI) occurred in all 4 patients in Group 1, with the mean peak MB-CPK of 356 +/- 197 IU/l. One patient had delayed sternal closure because of his unstable hemodynamic status. Thereafter, we changed our protocol as follows: 1) Ergometrine loading (intracoronary infusion) test was performed in all candidates for CABG, aiming at finding out patients with a high risk. And for the high-risk patients, in addition to the measures done in Group 1, 2) intraaortic balloon pumping was performed through the perioperative period, and 3) a pig-tail catheter was dwelled in the Valsalva sinus, through which bolus doses of isosorbide dinitrate were injected frequently in this period. 4) Additionally nifedipine was periodically administered through the nasogastric tube. With these intensive preventive/suppressive measures, the perioperative spasm in 5 patients (Group 2) with variant angina were successfully managed, with no resultant PMI nor operative death (The occurrence of PMI was significantly less frequent in Group 2 than in Group 1, with the p value < 0.05). For patients with variant angina undergoing CABG, combined intensive preventive/suppressive measures for perioperative coronary spasm as listed above proved effective.

Adult↗
PubMed1994

[A case report of reconstructive operation in traumatic tricuspid regurgitation].

Tricuspid regurgitation due to non-penetrating trauma occurred in a 21-year-old male patient who had received chest trauma in a motorcycle accident. Echocardiography demonstrated prolapse of the tricuspid anterior leaflet into the right atrium and massive tricuspid regurgitation. He was diagnosed as traumatic tricuspid regurgitation from his past history of the trauma. A reconstructive operation was performed successfully 4 years after the trauma. The chordal rupture of the anterior tricuspid leaflet was repaired using PTFE suture and annuloplasty of the dilated annulus was made using Carpentier ring. Tricuspid regurgitation was completely repaired as shown by the postoperative echocardiogram.

Adult↗
PubMed1994

[CSF dynamics in the patients with syringomyelia associated with Chiari's malformation--quantitative analysis on cine MRI].

In a series of 12 patients with syringomyelia associated with Chiari's malformation, the authors quantitatively analyzed cerebrospinal fluid (CSF) dynamics in the subarachnoid space of the craniospinal junction, using cine MRI combined with pre-saturation method. In most of subjects, cine MRI revealed (1) decreased or increased maximum velocity of CSF in the caudal direction and (2) disturbed CSF motion in the caudal direction (delayed % cardiac cycle) in the craniospinal junction, strongly suggesting disturbed CSF dynamics in the craniospinal junction because of the tonsilar herniation. Of 12 subjects, 8 patients underwent foramen magnum decompression and 4 underwent syringo-subarachnoid shunt (SS shunt). In the patients who showed marked collapse of syrinx after foramen magnum decompression, follow-up cine MRI revealed the normalization of % cardiac cycle, representing postoperative improvement of CSF dynamics in the craniospinal junction. On the other hand, % cardiac cycle did not improve significantly in the patients who did not show marked collapse of the syrinx or suffered from meningitis after surgery. Significant changes were not observed in the patients who underwent SS shunt. In summary, these results suggested that cine MRI combined with pre-saturation method could detect the pathophysiological changes and evaluate the efficacy of the surgery, especially foramen magnum decompression, in the patients with syringomyelia associated with Chiari's malformation.

Adolescent↗
PubMed1994

[Evaluation of prognostic nutritional index (PNI) as a prognostic indicator in multimodal treatment for gynecological cancer patients].

We assessed the usefulness of PNI (PNI = 10 x serum albumin + 0.005 x peripheral lymphocytes) as a prognostic indicator and determinant of multimodal treatment for 30 gynecological patients (control group: 12 patients with gynecological benign disease; good prognostic group: 10 with more than two-year survival having gynecological cancer; poor prognostic group: 8 with less than one-year survival having gynecological cancer). It was concluded that 1) PNI of the poor prognostic group was significantly lower than that of good prognostic group and control group (p < 0.01); 2) PNI is effective as a prognostic indicator; and 3) PNI is useful in clinical practice as a determinant of the multimodal treatment and high risk group.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

[Clinicopathologic analysis of ossification in spinal meningioma].

Calcification such as psammoma body is sometimes found especially in spinal cord meningioma but ossification of the meningeal tumor was rarely observed. Two cases of ossificated spinal cord meningiomas, located extramedullary intradurally apart from spinal bone, were clinicopathologically analyzed. The patients were 75-year-old female with meningioma at T9-10 level and 60-year-old female with one at T6-8 level. With pathological examination, concentration of psammoma bodies is not related to the formation of bone tissue. Metaplasia of arachnoid cell is seemed to be the origin of the bone structure.

Aged↗
PubMed1994

Granulocyte proteases and hydrogen peroxide synergistically inactivate thrombomodulin of endothelial cells in vitro.

Leukocytes release lysosomal proteases and reactive oxygen species in response to various stimuli that damage the adjacent endothelial cells. We investigated the effects of granulocyte lysosomal proteases (granulocyte elastase [GE] and cathepsin G [CG] and/or hydrogen peroxide (H2O2) on thrombomodulin (TM) activity of endothelial cells. We wished to determine whether the activated leukocytes damage the nonthrombogenic systems of endothelial cells. When cultured human umbilical vein endothelial cells (HUVECs) were incubated with GE, TM activity of the cells (as judged by the protein C activation capacity) decreased to about 10% of control with the concomitant increase of immunoreactive TM concentration in the conditioned media. CG also decreased TM activity to about 20% of control with the concomitant increase in immunoreactive TM concentration in the conditioned media. The GE- or CG-induced inactivation of TM was not observed in the presence of alpha 1-proteinase inhibitor. Immunoblot analysis showed that CG cleaved purified TM to yield one major fragment with an M(r) of 43,000; TM activity of this fragment was about 10% of the control activity. When purified TM was incubated with GE, TM activity decreased to 10% of control, and no detectable band was found on immunoblotting, suggesting that CG and GE cleave TM into inactive fragments and that GE degrades the epitope structure of TM. Although H2O2 (1.0 mmol/L) enhanced chromium 51 release from prelabeled HUVECs after 30 minutes of incubation, it decreased TM activity only slightly.(ABSTRACT TRUNCATED AT 250 WORDS)

Cathepsin G↗