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F Hirai

Publications and source records attributed to F Hirai.

12 recordsLinked to original sources
PubMed2001

Overexpression of mitochondrial manganese superoxide dismutase protects against radiation-induced cell death in the human hepatocellular carcinoma cell line HLE.

We investigated the potential role of mitochondrial manganese superoxide dismutase (Mn-SOD) in protective activity against irradiation by analyzing cell viability by a colony formation assay and by detecting apoptosis in stably human Mn-SOD gene-transfected HLE, a hepatocellular carcinoma cell line. We found that overexpression of Mn-SOD reduced the levels of reactive oxygen species in the mitochondria and intracellular phospholipid peroxidation product (4-hydroxy-2-nonenal) and prevented cell death. The production of intracellular nitric oxide after irradiation was not changed by Mn-SOD overexpression. The results suggested that Mn-SOD might play an important role in protecting cells against radiation-induced cell death by controlling the generation of mitochondrial reactive oxygen species and intracellular lipid peroxidation.

Apoptosis↗
PubMed1998

[Long-term clinical course and prognosis of patients with Crohn's disease].

The aim of the present study is to clarify long-term clinical course, prognosis and factors influencing prognosis of patients with Crohn's disease suffering for more than 10 years. Sixty-eight patients (47 males, 21 females) with Crohn's disease in whom the clinical course could observed well at our hospital for more than 10 years were studied. We classified these patients into three groups (good, fair, bad) according to their changes of IOIBD assessment score. And we compaired some clinical factors in these groups to clarify factors influencing prognosis. The results were as follows: 1) Twelve patients (18%) were in good prognosis group, and 24 patients (35%) in fair one, and 32 patients (47%) in bad one. 2) IOIBD assessment score at the time of diagnosis, site of leision, and radiographic findings at the time of diagnosis showed significant difference between bad prognosis group and the other two groups. Although there have been many reports that Crohn's disease is generally progressive, our results indicated that more than half of the patients showed favorable prognosis during the follow-up period for more than ten years.

Adult↗
PubMed1997

Beclomethasone dipropionate administration via cecostomy in ulcerative colitis.

Beclomethasone dipropionate was administered via a cecostomy to four patients with active ulcerative colitis that was refractory to conventional glucocorticosteroid therapy. From a tube cecostomy, beclomethasone dipropionate solution was administered continuously throughout the day. Clinical manifestations, laboratory examinations, and endoscopic and/or radiographic findings markedly improved within 1-2 wk. A serial decrease in the index of disease activity was observed from the time administration began (mean score, 226.0) to 2 wk later (137.4 points). An excellent clinical response was recognized without any significant side effects, and the urgent need for total colectomy was avoided in all four patients.

Adult↗
PubMed1991

Significant efficiency findings while controlling for the frequent confounders of CAI research in the PlanAlyzer project's computer-based, self-paced, case-based programs in anemia and chest pain diagnosis.

Richard E. Clark in his widely published comprehensive studies and meta-analyses of the literature on computer assisted instruction (CAI) has decried the lack of carefully controlled research, challenging almost every study which shows the computer-based intervention to result in significant post-test proficiency gains over a non-computer-based intervention. We report on a randomized study in a medical school setting where the usual confounders found by Clark to plague most research, were carefully controlled. PlanAlyzer is a microcomputer-based, self-paced, case-based, event-driven system for medical education which was developed and used in carefully controlled trials in a second year medical school curriculum to test the hypothesis that students with access to the interactive programs could integrate their didactic knowledge more effectively and/or efficiently than with access only to traditional textual "nonintelligent" materials. PlanAlyzer presents cases, elicits and critiques a student's approach to the diagnosis of two common medical disorders: anemias and chest pain. PlanAlyzer uses text, hypertext, images and critiquing theory. Students were randomized, one half becoming the experimental group who received the interactive PlanAlyzer cases in anemia, the other half becoming the controls who received the exact same content material in a text format. Later in each year there was a crossover, the controls becoming the experimentals for a similar intervention with the cardiology PlanAlyzer cases. Preliminary results at the end of the first two full trials shows that the programs have achieved most of the proposed instructional objectives, plus some significant efficiency and economy gains. 96 faculty hours of classroom time were saved by using PlanAlyzer in their place, while maintaining high student achievement. In terms of student proficiency and efficiency, the 328 students in the trials over two years were able to accomplish the project's instructional objectives, and the experimentals accomplished this in 43% less time than the controls, achieving the same level of mastery. However, in spite of these significant efficiency findings, there have been no significant proficiency differences (as measured by current factual and higher order multiple choice post-tests) between the experimental and control groups. Very careful controls were used to avoid what Clark has found to be the most common confounders of CAI research. Accordingly, this research proved Clark's rival hypothesis, that the computer, in itself, does not appear to contribute to proficiency gains, at least as measured by our limited post-testing. Clark's position is that the computer is primarily a vehicle--as is either a pill or a hypodermic needle for delivering a drug.(ABSTRACT TRUNCATED AT 400 WORDS)

Anemia↗
PubMed1991

Findings from an evaluation of PlanAlyzer's double cross-over trials of computer-based, self-paced, case-based programs in anemia and chest pain diagnosis.

We report on three years of research trials of the PlanAlyzer I Project--a carefully controlled research study using a microcomputer-based, self-paced, case-based, event-driven system for medical education. PlanAlyzer presents cases, elicits and critiques a second year student's approach to the diagnosis of anemias and chest pain. PlanAlyzer uses text, hypertext, images and critiquing theory. Students were randomized, one half becoming the experimental group who received the interactive PlanAlyzer cases in anemia, the other half becoming the controls who received the exact same content material in a text format. Later in each year there was a crossover, the controls becoming the experimentals for a similar intervention with the cardiology PlanAlyzer cases. Results at the end of the first two years of trials show that the programs have achieved some significant efficiency and economy gains. 96 faculty hours of classroom time were saved by using PlanAlyzer in their place, with no loss in student achievement. In terms of student proficiency and efficiency, combining the anemia and cardiology trials, the 328 students in the two years of full scale trials were able to accomplish the project's instructional objectives. The experimentals accomplished this in 43% less time than the controls. On the average, for both the anemia and chest pain programs, this amounted to students spending 7.5 hours longer on the 30 text cases than on the same 30 computer cases to achieve the same level of mastery. There have been no significant proficiency differences (as measured by current post-tests) between the experimental and control groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Anemia↗
PubMed1989

Computer-based exercises in anemia diagnosis (PlanAlyzer).

PlanAlyzer is a microcomputer-based, event-driven system for instructional research in medical education. Aimed at the second year medical student, PlanAlyzer elicits and critiques a student's approach to the diagnosis of a common medical disorder. In this paper we discuss the concept, development, implementation and formative evaluation of the PlanAlyzer system for the evaluation of anemia.

Anemia↗
PubMed1984

Significance of mitochondrial enhancement in hepatic energy metabolism in relation to alterations in hemodynamics in septic pigs with severe peritonitis.

Liver mitochondrial phosphorylative activity, hepatic adenine nucleotides, and hemodynamic parameters were studied in 23 pigs with peritonitis induced by cecal ligation and perforation. Between 2 and 7 days after treatment, the onset of an apparent hyperdynamic state, characterized by an increased cardiac index and decreased total peripheral resistance index, occurred. In this period, the energy charge level was barely maintained and the occurrence of liver mitochondrial enhancement was observed. However, 10-14 days after treatment, the onset of a hypodynamic state with its inverse patterns in hemodynamics took place. In this period, the energy charge level fell to 0.68, concomitant with a marked decrease in mitochondrial function. Further, a high positive correlation between the cardiac index and liver mitochondrial phosphorylative activity was noted (r = 0.85, p less than 0.01). These results suggest that liver mitochondria play a major role in the metabolic and hemodynamic adaptations occurring during sepsis.

Adenine Nucleotides↗
PubMed1984

Hepatic and systemic metabolic responses to aerobic and anaerobic intra-abdominal abscesses in a highly reproducible chronic rat model.

A single, uniform abscess was formed in 100% of the animals inoculated with a fecal pellet made of sterile rat feces, agar, and a known number and strain of bacteria. The effects of monoclonal Escherichia coli abscess (83 rats) were compared to those of sterile abscess (34 rats) and sham operation (35 rats without abscess). Bacteroides fragilis was added to the sterile pellet to study the effect of an anaerobic monoclonal abscess (16 rats) or of a biclonal abscess containing both aerobes and anaerobes (32 rats). After inoculation, a peritonitis stage with leucopenia, hypoglycemia, body weight loss, and slight fever was followed by the abscess stage with leucocytosis and a slight hyperglycemia. Mild hepatic energy charge deficiency and hepatic lactic acidosis were observed in sterile abscess rats, and slightly enhanced energy charge was seen in monoclonal E. coli abscess rats. The addition of B. fragilis to the sterile pellet, alone or together with E. coli, produced hepatic energy charge deficiency and hepatic lactic acidosis, which were significantly enhanced compared with the monoclonal E. coli abscess rats. The greatest effect was seen in the biclonal E. coli plus B. fragilis abscess, suggesting that anaerobic or combined aerobe and anaerobe abscesses may produce a greater hepatic injury than an aerobic organism abscess alone. This may account for the apparent synergic interaction between aerobic and anaerobic organisms.

Abdomen↗
PubMed1982

Clinical experience of postoperative hepatic failure treatment with pig or baboon liver cross-hemodialysis with an interposed membrane.

The present study emphasizes the principle of using liver support to restore the blood ketone body ratio (acetoacetate/beta-hydroxybutyrate), which reflects the redox potential of liver mitochondria and correlates with hepatic energy charge (ATP + 0.5ADP/ATP + ADP + AMP). Eleven surgical patients with grade IV hepatic coma were treated by an ex vivo pig or baboon liver cross-hemodialysis with an interposed Cuprophan membrane when their blood ketone body ratios had decreased to below 0.4 compared with the normal of above 0.7. Three patients were treated by cross-hemodialysis using a standard Cuprophan membrane dialyzer without increase of blood ketone body ratio and without marked beneficial effect. However, five of eight patients who had blood ketone body ratios of above 0.25 became fully alert after treatment by cross-hemodialysis using the larger pore size and greater surface area Cuprophan membrane, concurrent with a rise in the decreased blood ketone body ratio, and three of them were later discharged. By contrast, in the three patients with blood ketone body ratios below 0.25, there was no restoration of consciousness and no improvement in their blood ketone body ratios by this liver support. It is suggested that, as long as the blood ketone body ratio remained over 0.25, this metabolic liver support is effective in restoring grade IV hepatic coma.

Aged↗
PubMed1982

The effects of heterologous liver cross-hemodialysis on adenylate energy charge of the remnant liver after major hepatic resection.

The effect of liver support on the adenylate energy charge (ATP + 0.5ADP)/(ATP + ADP + AMP) of the remnant liver after major hepatic resection was studied in rabbits. The present study emphasized the principle of restoring the decreased energy charge level of the remnant liver after major hepatic resection by use of an ex vivo heterologous liver cross-hemodialysis with an interposed Cuprophan membrane. The energy charge level provides the cell with a very sensitive intracellular control mechanism. Regulatory enzymes from biosynthetic sequences exhibit very little activity at low levels of energy charge, and their activities increase sharply at high-energy charge levels. The energy charge level of the remnant liver maximally decreased from the control level of 0.860 to 0.767 at 24 hours after 70% hepatectomy. The energy charge level increased from 0.767 to 0.857 after two hours of cross-hemodialysis with an interposed Cuprophan membrane between the 24-hour, 70% hepatectomized rabbit and an ex vivo pig liver with high energy charge. The above results suggest that this ex vivo pig cross-hemodialysis may be effective for biosynthesis in the regenerative processes of the remnant liver.

Adenosine Monophosphate↗