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Biomedical subjects

Y Umemoto

Publications and source records attributed to Y Umemoto.

At least 19 recordsLinked to original sources

Clinical features and management of hepatic portal venous gas: four case reports and cumulative review of the literature.

HYPOTHESIS: Hepatic portal venous gas (HPVG) has been considered a rare entity associated with a grave prognosis. Since 1978, when Liebman et al reviewed 64 cases of HPVG and reported a mortality of 75%, the number of reported cases has been increasing. DESIGN: Case series. PATIENTS AND METHODS: We reviewed the literature on 182 cases of HPVG in adults, including 4 of our patients, (transplantation and abdominal trauma cases were excluded) and analyzed the cause, pathogenesis, and clinical features. RESULTS: In this series, the underlying clinical events associated with HPVG were bowel necrosis (43%), digestive tract dilatation (12%), intraperitoneal abscess (11%), ulcerative colitis (4%), gastric ulcer (4%), Crohn disease (4%), complications of endoscopic procedures (4%), intraperitoneal tumor (3%), and other (15%). The overall mortality was 39% but varied depending on the underlying disease. CONCLUSIONS: Hepatic portal venous gas is a lethal or curable entity caused by various diseases. The underlying disease associated with HPVG determines the clinical features and prognosis of the patients. The treatment of patients with HPVG should be directed to the underlying disease.

Aged↗

Involvement of calpain for apoptosis in dysfunction of the unaffected testis in rats with experimental testicular torsion.

PROBLEM: The dynamics of calpain and involvement of apoptosis in sperm formation disorder of the unaffected testis in rats with experimental testicular torsion were investigated. METHODS OF STUDY: Using 6-week-old Wistar rats, an experimental unilateral testicular torsion model was prepared. The bilateral testes were excised 1, 3, 5, 7, 14, 35, and 70 days after the left testis was twisted, and the unaffected testes were subjected to immunohistological staining, sodium dodecyl sulfate polyacrilamide gel electrophoresis and Western blotting using anti-calpain antibodies. Apoptosis was detected by the TdT-mediated dUTP biotin nick end-labeling (TUNEL) method. RESULTS: By immunohistological staining, positive immunostaining by anti-pro mu-calpain antibody was observed in the spermatocyte nucleus, but not with anti-pro m-calpain antibody. The staining was increased until 7 days after testicular torsion, then decreased with progression of sperm formation disorder. By Western blotting, the intensity of staining with anti-pro mu-calpain antibody was increased until 7 days after torsion of the testis. Apoptosis expression in the unaffected testis was significantly inhibited by addition of a calpain inhibitor. CONCLUSIONS: It was suggested that mu-calpain may be involved in apoptosis expression in sperm formation disorder of the unaffected testis in unilateral testicular torsion.

Animals↗

Venous blood flow measurement by determination of change in venous hemoglobin saturation.

OBJECTIVE: To evaluate a method of measuring venous blood flow in vitro by using the Fick principle and change in saturation of venous blood and to apply the method to the clinical measurement of hepatic blood flow. DESIGN: Experimental study using an in vitro model and clinical study for critically ill patients. SETTING: Department of Anesthesiology and Intensive Care Medicine in Osaka City University Medical School. MODEL: Human blood deoxygenated by bubbling of nitrogen was circulated in a closed circuit at 10-120 mL/min by a roller pump. A fiber optic sensor was attached to the circuit for continuous monitoring of hemoglobin saturation. PATIENTS: Eight critically ill patients, aged 54.3 +/- 15.1 yrs, were studied. INTERVENTIONS: Hemoglobin saturation was changed in the in vitro study by the injection of 0.2 mL of oxygenated blood. Signals from the optical fiber were analogue-digital converted and recorded in a computer. In the clinical study, an oximetry catheter was inserted into the inferior vena cava (IVC) via the femoral vein. Arterial blood (10 mL) was drawn from the radial artery, and injected into the IVC. The changes in oxygen saturation in the venous blood were recorded. MEASUREMENTS AND MAIN RESULTS: Blood flow was calculated using the Fick principle, assuming that all the injected blood passes through the sensor. In vitro estimation of blood flow was well correlated with the actual flow (r2 = .94). IVC blood flow was measured above and below the merging point of the hepatic vein. The difference of the two values was assumed to represent hepatic blood flow. IVC blood flow was calculated by the same method as for the in vitro study. The blood flows in the IVC above and below the anastomosis with the hepatic vein were 2.82 +/-0.56 (SD) Umin and 1.96 +/- 0.61 (SD) L/min. Average estimated hepatic blood flow was 0.86 L/min (range, 0.34-1.75 Umin). CONCLUSION: We examined the accuracy and reliability of this new method in the present in vitro study. This method may be clinically useful for measuring hepatic blood flow.

Adult↗

[Emphysematous pyelonephritis complicated with diabetes mellitus: a case report].

A 46-year-old woman with diabetes mellitus was admitted to our hospital due to lower right abdominal pain. Urinalysis did not show marked pyuria. Abdominal computed tomography showed an abnormal gas shadow in the right renal parenchyma. A diagnosis was made of right emphysematous pyelonephritis. Despite aggressive supportive therapy, the patient's condition worsened. Therefore, right nephrectomy was performed. The next day her general condition was markedly improved. We reviewed 122 cases of emphysematous pyelonephritis including our case in the Japanese literature, and discussed its etiology, symptomatology, choice of treatment and prognosis.

Diabetes Complications↗

[A case of successful hypospadias repair without infection using recombinant human granulocyte-colony stimulating factor (rhG-CSF) for idiopathic neutropenia].

A boy aged 1 year 8 months, who was referred to our hospital because of hypospadias, was followed for 17 months under a diagnosis of idiopathic neutropenia. He was given recombinant human granulocyte colony-stimulating factor (rhG-CSF) at a dosage of 37.5 micrograms/day for 2 days preoperatively. His absolute neutrophil count in peripheral blood increased to more than 500/microliter, and hypospadias repair (free graft method) was performed. RhG-CSF was administered on the first, sixth, and eleventh days after the operation, and the postoperative course was uneventful. During pediatric surgery in patients with neutropenia, appropriate administration of rhG-CSF may be useful for preventing infection.

Granulocyte Colony-Stimulating Factor↗

[Composite pheochromocytoma with ganglioneuroma in the adrenal gland: a case report].

A 67-year-old male demonstrated a right adrenal tumor at another hospital, and consulted our hospital for surgical treatment. Abdominal computed tomography revealed a 13 x 12 cm mass in the right adrenal region. Serum and urinary adrenaline levels were high, and the catecholamine levels in the blood sample of the selective adrenal vein were also high. The tumor was 1,325 g in weight and 13 x 9 x 18 cm in diameter. Pathological diagnosis was a mixed neuroendocrine-neural tumor. It was composed of pheochromocytoma and ganglioneuroma. This combination in the adrenal gland is rare. We reviewed 3 previously reported cases of composite pheochromocytoma with gangloineuroma in the adrenal gland in the Japanese literature, and this is considered to be the fourth case.

3-Iodobenzylguanidine↗

Leptin stimulates the proliferation of murine myelocytic and primitive hematopoietic progenitor cells.

Leptin, the product of obese gene, was originally identified as a factor regulating body-weight homeostasis and energy balance. The present study has shown that leptin acts on murine hematopoiesis in vitro. In the culture of bone marrow cells (BMC) of normal mice, leptin induced only granulocyte-macrophage (GM) colony formation in a dose-dependent manner, and no other types of colonies were detected even in the presence of erythropoietin (Epo). Leptin also induced GM colony formation from BMC of db/db mutant mice whose leptin receptors were incomplete, but the responsiveness was significantly reduced. The effect of leptin on GM colony formation from BMC of normal mice was also observed in serum-free culture, and comparable with that of GM-colony-stimulating factor (CSF ). Although leptin alone supported few colonies from BMC of 5-fluorouracil (5-FU)-treated mice in serum-free culture, remarkable synergism between leptin and stem cell factor (SCF ) was obtained in the colony formation. The addition of leptin to SCF enhanced the SCF-dependent GM colony formation and induced the generation of a number of multilineage colonies in the presence of Epo. When lineage (Lin)-Sca-1(+) cells sorted from BMC of 5-FU-treated mice were incubated in serum-free culture, leptin synergized with SCF in the formation of blast cell colonies, which efficiently produced secondary colonies including a large proportion of multilineage colonies in the replating experiment. In serum-free cultures of clone-sorted Lin-c-Kit+Sca-1(+) and Lin-c-Kit+Sca-1(-) cells, although synergism of leptin and SCF was observed in the colony formation from both cells, leptin alone induced the colony formation from Lin-c-Kit+Sca-1(-), but not Lin-c-Kit+Sca-1(+) cells. These results have shown that leptin stimulates the proliferation of murine myelocytic progenitor cells and synergizes with SCF in the proliferation of primitive hematopoietic progenitors in vitro.

Animals↗

A case of lymphoid interstitial pneumonia in a 3-month-old boy not associated with HIV infection: immunohistochemistry of lung biopsy specimens and serum transforming growth factor-beta 1 assay.

The case of a 3-month-old boy with lymphoid interstitial pneumonia (LIP) is reported. He had cough and tachypnea, his weight gain was poor and a chest radiograph showed microgranular shadows in almost all lung areas. Histological investigations revealed severe cellular infiltration by a variety of lymphoid and plasma cells with lymphoid follicle formation in the alveolar walls and also around the bronchioles. Foamy macrophages, a few lymphocytes and exudate filled the alveolar spaces. Epithelial cells lining the air spaces expressed human leukocyte antigen (HLA)-DR. Lymphocytes and macrophages in the alveolar spaces expressed transforming growth factor (TGF)-beta strongly. Serum TGF-beta 1 concentrations were measured eight times during the course of his illness. They exceeded the upper end of the normal range in four samples and were within it in the others. These results suggested that dysfunction of the immune system, especially abnormal expression of HLA-DR in non-immune cells and exaggerated production of TGF-beta played important roles in the pathogenesis of LIP in this patient.

Antigens, CD↗

[The effects of vasoconstrictors on distribution of ischemic tissue flow in isolated perfused rat liver].

We studied the effects of ATP and epinephrine on distribution of ischemic hepatic tissue flow in the isolated perfused rat liver. Five minutes after clamping both the portal vein and hepatic artery, perfusion was started. Lidocaine was infused into the portal vein, and the concentration of lidocaine in hepatic outflow was measured with FPIA. The oxygen extraction ratio was also measured. Tissue surface blood flow was measured with laser-Doppler flowmetry. We measured the tissue flow at 2 points: one where flow was more than 10 ml.min-1.100 gm liver weight-1 (R), and the other where flow was less than 10 ml.min-1.100 gm liver weight-1 (P). After perfusion pressure had become stable, ATP or epinephrine was infused for 15 minutes. Perfusion pressure increased, and tissue flow of R decreased significantly, while that of P increased (not significantly). The extraction ratio of lidocaine decreased significantly by epinephrine, and that of oxygen decreased (not significantly). We conclude that in the ischemic liver, vasoconstriction results in changes in the distribution of tissue blood flow and alters drug metabolism.

Adenosine Triphosphate↗

[Isolation rate of Enterococcus spp. from surgical infections and their susceptibilities].

Enterococcus spp. isolated from surgical infections during the period from July 1982 to June 1995 were investigated in a multicenter study involving 19 hospitals in Japan, and the following results were obtained. 1. Though the isolation rate of Enterococcus faecalis and other Enterococcus spp. were not high from primary infections, and from postoperative infections the isolation rate of other Enterococcus spp. was also low, the isolation rate of E. faecalis was highest from postoperative infections after 1993. 2. Vancomycin (VCM) showed strongest activity against E. faecalis, and followed by those of ampicillin (ABPC), imipenem. levofloxacin (LVFX) and meropenem in this order. Against other Enterococcus spp., VCM showed strongest activity, and followed by those of ABPC and LVFX. There were no resistant strains against VCM.

Ampicillin↗

[Isolation rate of E. coli from surgical infections and their susceptibilities].

Escherichia coli isolated from surgical infections during the period from July 1983 to June 1995 were investigated in a multicenter study involving 19 hospitals in Japan, and the following results were obtained. 1. Although the isolation rate of E. coli was not high from postoperative infections, it was most frequently isolated from primary infections throughout the study period. E. coli, Klebsiella spp. and anaerobic bacteria were predominant from fresh infections. From the cases that had previous antibiotics treatment, Enterococcus spp. were the most predominant isolates followed by MRSA and Pseudomonas spp. in this order. 2. Against E. coli, cefozopran, carumonam and aztreonam had the strongest activity, followed by cefmenoxime, imipenem, latamoxef, gentamicin and ofloxacin. Recently, we have noticed that antibiotic resistant E. coli strains particularly against cefazolin are increasing year by year.

Anti-Bacterial Agents↗

[Isolation rate of Pseudomonas aeruginosa from surgical infections and their susceptibilities].

Pseudomonas aeruginosa isolated from surgical infections during the period from July 1982 to June 1995 were investigated in a multicenter study involving 19 hospitals in Japan, and the following results were obtained. 1. Though the isolation rate of P. aeruginosa was not high from primary infections, it was more frequently isolated from postoperative infections throughout the study period. Enterococcus spp., P. aeruginosa and Staphylococcus aureus including MRSA were predominant among postoperative infections. From the postoperative cases that had previous antibiotic treatment, Enterococcus spp., MRSA and P. aeruginosa were more predominantly isolated than from those without previous treatments with antibiotics. 2. Cefozopran, ceftazidime, cefsulodin, aztreonam, carumonam, gentamicin, amikacin and ofloxacin had strong activities against P. aeruginosa. We recognize recently that antibiotic-resistant strains of P. aeruginosa against imipenem and ofloxacin have been increasing year by year.

Anti-Bacterial Agents↗

[Bacteria isolated from surgical infections and its susceptibilities to antimicrobial agents. Special references to bacteria isolated between July 1994 and June 1995].

Isolated bacteria from infections in general surgery during the period from July 1994 to June 1995 were investigated by a multicenter study in Japan, and the following results were obtained. One hundred and fifty-three strains were isolated from primary infections, and 143 strains were isolated from postoperative infections. From primary infections, both anaerobic Gram-positive and-negative bacteria were predominant, and from postoperative infections, aerobic Gram-positive bacteria were predominant. Among aerobic Gram-positive bacteria, the isolation rate of Enterococcus faecalis was highest, followed by that of Staphylococcus aureus from both types of infections. Among anaerobic Gram-positive bacteria, the isolation rate of Streptococcus intermedius was highest from primary infections, but from postoperative infections anaerobic Gram-positive bacteria was uncommon. Among aerobic Gram-negative bacteria, Escherichia coli was most predominantly isolated from primary infections, followed by Klebsiella pneumoniae and Pseudomonas aeruginosa in this order. From postoperative infections, P. aeruginosa was most predominantly isolated, followed by Serratia marcescens and E. coli. Among anaerobic Gram-negative bacteria, the isolation rate of Bacteroides fragilis group was the highest from both types of infections. We have noticed that resistant strains against imipenem and ofloxacin were increasing among P. aeruginosa and resistant strains against cefazolin were increasing among E. coli. MICs of cefazolin against four out of 30 strains of E. coli were higher than 100 micrograms/ml, and MICs of imipenem was higher than 50 micrograms/ml against 5 out of 22 strains of P. aeruginosa.

Anti-Bacterial Agents↗

[Current occurrence and infection control of MRSA enteritis for surgical patients in Japan (first report)].

We investigated the current occurrence and the infection control of MRSA enteritis in the surgical facilities in Japan from July 1990 to June 1992. In this two years, MRSA enteritis was encountered in 831 cases in 144 of 279 facilities (51.6%) which had replied to our survey. Frequency of onset of MRSA enteritis in the surgical specialty was 95% in abdominal surgery and general surgery. Nosocomial infection controls for MRSA infection were done in 92.1% of 261 facilities who replied to our questionnaire. Preventive control in the preoperative and postoperative periods were performed in 23.8%. Various controls for MRSA enteritis were recognized and enforced in 56.7% with restriction of postoperative antibiotics, 65.5% with environmental controls, 70.5% with preventive control for the medical staff and 42.9% with the control for the expansion of nosocomial MRSA infections.

Cross Infection↗