Biomedical subjects

O Mikami

Publications and source records attributed to O Mikami.

At least 37 records · Page 2Linked to original sources

PubMed1998

High intra-abdominal pressure increases plasma catecholamine concentrations during pneumoperitoneum for laparoscopic procedures.

BACKGROUND: Laparoscopic procedures are associated with several complications, such as hemodynamic, respiratory, and endocrine complications. In our previous clinical study, plasma epinephrine and norepinephrine concentrations remained unchanged after the insertion of a Veress needle, but increased significantly immediately after insufflation with carbon dioxide into the peritoneum. The mechanisms for this increase are unknown. OBJECTIVE: To investigate whether gas insufflation during pneumoperitoneum affects plasma catecholamine concentrations during laparoscopic procedures. DESIGN: Experimental study in pigs. MAIN OUTCOME MEASURES: The plasma concentrations of epinephrine and norepinephrine were measured in the pigs before and after pneumoperitoneum. The mean arterial pressure, heart rate, cardiac output, and arterial blood gas levels were measured, and the systemic vascular resistance was calculated. INTERVENTION: Air, nitrous oxide, or carbon dioxide were insufflated in turn into the peritoneal cavity of supine pigs. Thereafter, carbon dioxide was insufflated into the peritoneal cavity while the pig was in the left lateral decubitus position, and then in the right lateral decubitus position. Measures were performed before pneumoperitoneum and at the intra-abdominal pressures of 10 mm Hg and 20 mm Hg. One hour of resting time was allowed between each procedure. RESULTS: As compared with baseline values, the plasma concentrations of epinephrine and norepinephrine remained unchanged at 10 mm Hg but increased significantly at 20 mm Hg regardless of the gas used for the pneumoperitoneum (P<.05). The type of gas and differences in the position of the animals had no effect on the plasma epinephrine and norepinephrine concentrations. CONCLUSIONS: Excessive intra-abdominal pressure, but not the type of gas or body position, increases plasma catecholamine concentrations during the insufflation of gas into the abdominal cavity. Therefore, excessive insufflation of the pneumoperitoneum should be avoided.

Abdomen↗

PubMed1998

The effects of the lateral position on cardiopulmonary function during laparoscopic urological surgery.

UNLABELLED: Laparoscopic urological surgery is usually performed transperitoneally with retroperitoneal insufflation of carbon dioxide (CO2) in the lateral position. We studied whether a difference in the side of lateral position affected hemodynamic and pulmonary functions during pneumoperitoneum. Fifteen patients (eight in the right and seven in the left lateral position) undergoing elective laparoscopic urological surgery were studied under general anesthesia. Hemodynamic variables and blood gas data were recorded. Before insufflation, mean arterial pressure (MAP), mean pulmonary arterial pressure (MPAP), central venous pressure (CVP), and pulmonary capillary wedge pressure (PCWP) in the right lateral position were higher than those in the left lateral position. Pneumoperitoneum increased MAP, MPAP, CVP, PCWP, and cardiac index but decreased systemic vascular resistance in the right lateral position. Similar changes occurred during pneumoperitoneum in the left lateral position, but the changes were less than those in the right lateral position. The respiratory index (PaO2/PAO2), intrapulmonary shunt, and SpO2 did not change during pneumoperitoneum in either lateral position. Changing the side of the lateral position affected hemodynamic function but did not affect pulmonary oxygenation during pneumoperitoneum. IMPLICATIONS: The right and left lateral positions produced different hemodynamic changes during laparoscopic urological surgery. The increases in preload and cardiac index and the decrease in systemic vascular resistance were greater in the right than in the left lateral position. Respiratory changes were not affected differently between the right and left lateral positions.

Anesthesia, General↗

PubMed1997

Association of interleukin-6 in the cerebrospinal fluid during crisis of calf with ammoniated feed syndrome.

Ammoniated feed syndrome (AFS) in cattle is a neurotoxic syndrome caused by feeding specific ammoniated forage. To clarify the pathophysiology of AFS, we examined the association of interleukin-6 (IL-6) in the brain. By feeding milk either from cows fed such ammoniated forage or milk added with 4-methyl-imidazole, newborn calves showed a neurotoxic crisis of hyperexcitability, ataxia, muscle tremor, circling, roaring, epileptoid seizure, sweating and marked fever response. Although these calves had no pathological lesions in the brain, we detected a rise in IL-6 in the cerebrospinal fluid (CSF). Tumor necrosis factor-alpha (TNF-alpha) was not detected in the CSF. In the sera, IL-6 and TNF-alpha hardly changed during the experiment. Administration of recombinant human IL-6 into the lateral ventricle resulted in fever. Thus, we believe IL-6 in the CSF is related to the fever response in newborn calves with AFS.

Acute Disease↗

PubMed1997

Primary culture and expression of cytokine mRNAs by lipopolysaccharide in bovine Kupffer cells.

Kupffer cells are sessile tissue macrophages that have a role in liver defense against endogenous endotoxins. Because little information is available on the role of bovine Kupffer cells, we developed a primary culture method to investigate the function of bovine Kupffer cells. Kupffer cells were isolated from the caudate lobe of calf liver by perfusion with collagenase and pronase. Then, the cells were purified by gradient centrifugation followed by counterflow centrifugal elutriation. With the methods, a mean number of 1.5 x 10(6) Kupffer cells with a final viability of over 98% was obtained from 1 g of the liver. Over 95% of the isolated cells were positive for non-specific esterase activity and had surface molecule of CD68. The cultured Kupffer cells expressed mRNAs of tumor necrosis factor-alpha, interleukin (IL)-1 alpha, IL-1 beta and IL-6 by stimulation for 3 h with lipopolysaccharide. The primary culture of bovine Kupffer cells could be useful to investigate the systemic inflammatory response in bovine liver.

Animals↗

PubMed1997

Transperitoneal laparoscopic adrenalectomy: experience in 100 patients.

Between July 1992 and October 1996, 100 transperitoneal laparoscopic adrenalectomies were performed on 99 patients at our hospital and affiliated hospitals. The clinical diagnoses were primary aldosteronism (41 patients), Cushing's syndrome (15), pre-Cushing's syndrome (6), pheochromocytoma (7; 8 adrenal glands), adrenal cancer (2), nonfunctioning adenoma (22), myelolipoma (3), and complicated adrenal cyst (3). Ninety-seven glands were removed laparoscopically. The mean operative time was 240 +/- 76 (SD) minutes and the mean blood loss 68 +/- 80 mL for the series. The mean blood was 77 +/- 113 mL when the three operations that were converted to open surgery are included. The mean times for the return to a normal diet and unassisted ambulation were 1.3 +/- 0.6 and 1.4 +/- 0.8 days, respectively. The mean duration of the use of analgesics was 1.5 +/- 1.3 days, including the day of surgery. In contrast, in the latest 10 open adrenalectomies done at Kyoto University Hospital, the mean operative time was 186 +/- 53 minutes and the mean blood loss 220 +/- 170 mL. The mean times for return to a normal diet and for unassisted ambulation and the mean duration of the use of analgesics were 1.9 +/- 0.3, 2.9 +/- 1.1, and 2.9 +/- 1.7 days, respectively. Thirty-six operations, excluding one converted to open surgery, performed at Kyoto University Hospital were selected to look at the learning curve for transperitoneal laparoscopic adrenalectomy and evaluated for operative time and blood loss. The mean operative time and mean blood loss in the first 10 procedures performed at Kyoto University Hospital were 256 +/- 63 minutes and 89 +/- 57 mL; however, these values were reduced to 177 +/- 39 minutes and 48 +/- 32 mL in the next 10 procedures at the same hospital. Laparoscopic adrenalectomy via the transperitoneal anterior approach can be equivalent to open adrenalectomy in efficiency with a shorter convalescence.

Adrenal Gland Diseases↗

PubMed1997

[Metastatic tumor to the penis from lung and pancreas cancer: report of two cases].

Neoplasms metastasizing to the penis are uncommon, and occur at the end stage of carcinoma. We describe two patients with a metastatic lesion to the penis from lung squamous cell carcinoma and pancreatic adenocarcinoma. We reviewed 101 cases with secondary penile tumor. The prognosis of secondary penile tumor is extremely poor.

Adenocarcinoma↗

PubMed1997

[Clinical statistics on in-patients and operations during a 20-year period (1975-1994) at Department of Urology, Kansai Medical University].

The patients, diseases and operations experienced between 1975 and 1994 in our department were statistically analyzed. The numbers of in-patients and operations have been increasing since 1977. During these 20 years, endoscopic surgery has replaced many open surgical procedures. The introduction of extracorporeal shock wave lithotripsy has dramatically changed the therapeutic modality for urolithiasis, and decreased of the necessity of open surgery.

Female↗

PubMed1997

[Comparison of side effects caused by intra-arterial and intravenous infusion of M-VAC (methotrexate, vinblastine, adriamycin and cisplatin) for urothelial cancer].

We retrospectively studied the toxic effects in 14 patients with urothelial cancer who had undergone intra-arterial M-VAC chemotherapy (Group A) and 13 patients who had received intravenous M-VAC chemotherapy (Group V) between February 1991 and August 1995. No statistically significant differences were found in the white blood cell count nadir, liver function, renal function or appetite between the groups. While the platelet count nadir for intra-arterial infusion (14.0 x 10(4)/mm3) was larger than for intravenous infusion (9.0 x 10(4)), the median days to nadir for this count was shorter in the intra-arterial group (9.1 days) than in the intravenous group (13.5). In addition, the difference between the beginning hemoglobin level and the nadir level was larger in the intra-arterial infusion group (2.55 g/dl) than in the intravenous infusion group (1.95 g/dl). Additionally peculiar side effects were noted in the intra-arterial infusion group which included local erythema and nerve paralysis. Side effects should be managed for intra-arterial M-VAC as well as for intravenous infusion.

Aged↗

PubMed1996

Laparoscopic nephropexy: a case report.

The laparoscopic approach is an ideal method for nephropexy because it produces less postoperative pain and allows an early recovery. We report a case of symptomatic renal ptosis treated laparoscopically with good success.

Adult↗

PubMed1996

Respiratory effects of CO2 pneumoperitoneum during transperitoneal laparoscopic urological surgery.

OBJECTIVE: To evaluate the effects of CO2 pneumoperitoneum on respiratory function during urological laparoscopic surgery with exposure of the retroperitoneal space in the lateral decubitus position. METHODS: Arterial blood gas analysis and measurements of the partial pressure of CO2 in exhaled gas (PetCO2) were performed during CO2 pneumoperitoneum in 12 patients who underwent transperitoneal laparoscopic surgery for the retroperitoneal organs (the retroperitoneal group): the results were compared to those of 11 patients who underwent laparoscopic varicocelectomy (the varicocele group) with the same anesthesia and intra-abdominal pressure. RESULTS: The increase in PaCO2 and PetCO2 and the decrease in arterial pH during CO2 insufflation were significantly greater in the retroperitoneal group than in the varicocele group. PaCO2, PetCO2 and arterial pH continued to change in the retroperitoneal group, whereas these values reached a plateau at 30 min after the beginning of CO2 insufflation in the varicocele group. CONCLUSIONS: The respiratory effects of CO2 pneumoperitoneum are more pronounced during laparoscopic urological surgery with opening of the retroperitoneum. It is possible that exposure of the retroperitoneal space increased CO2 absorption during insufflation.

Adult↗

PubMed1996

[Angiotensin II receptors in a rat model of hypobaric hypoxic pulmonary hypertension].

Hypoxic pulmonary hypertension is characterized by profound remodeling of the walls of small pulmonary arteries: endothelial swelling and proliferation of media and adventitia to a degree that may narrow the lumen. The molecular mechanism responsible for these changes is unknown. Recent studies have demonstrated the existence of a vascular and cardiac renin-angiotensin system. This system can induce hypertrophy and proliferation of aortic smooth muscle cells and cardiac muscle cells in animal models of systemic hypertension. In the present experiments, Northern blot analysis and a receptor binding assay specific to angiotensin II (Ang II) receptors was used to study the pulmonary renin angiotensin system in a rat model of hypobaric hypoxic pulmonary hypertension. mRNA transcripts for the Ang II receptor AT(1A) were constitutively expressed, and specific binding of Ang II to the receptors occurred in lung tissue of control rats that breathed ambient air. After 3 days of hypobaric hypoxia (380 Torr), the AT(1A) mRNA level and the index of Ang II receptors had increased, but right ventricular hypertrophy was not still evident. Ang II receptors were significantly increased after 14 days of hypoxia, when histological evidence of pulmonary hypertension was observed. In addition, the Ang II level in pulmonary tissue was higher after 14 days of hypoxia than in normal controls. These findings suggest that the renin-angiotensin system in pulmonary tissue was activated in these rats, and that it contributes to the morphological changes observed in hypoxic pulmonary hypertension.

Animals↗

PubMed1996

Catecholamine release caused by carbon dioxide insufflation during laparoscopic surgery.

PURPOSE: We evaluated plasma catecholamine levels during pneumoperitoneum in laparoscopic surgery. MATERIALS AND METHODS: Plasma epinephrine and norepinephrine were evaluated in 29 patients who underwent laparoscopic retroperitoneal surgery in a half lateral decubitus position (group 1) or laparoscopic varicocelectomy in a Trendelenburg position (group 2). RESULTS: The levels of epinephrine and norepinephrine increased significantly 5 minutes after carbon dioxide insufflation compared to levels after Veress needle insertion and just before insufflation. The elevation of catecholamine levels during laparoscopic procedures was greater in group 1. CONCLUSIONS: Our results indicate that carbon dioxide insufflation may cause catecholamine release during laparoscopic surgery. Careful monitoring of hemodynamics is mandatory at the beginning of the procedure.

Adolescent↗

PubMed1995

Interferon alpha therapy for chronic active hepatitis type C after renal transplantation and allograft rejection.

An acute type rejection episode occurred in one of two patients treated with Interferon alpha (IFN alpha) for type C hepatitis (CHC). Histopathological examination of the graft kidney revealed focal cellular infiltration and chronic transplant glomerulopathy which showed acute or chronic type rejection. In spite of bolus administration of methyl-prednisolone, the elevation of serum creatinine level continued. After administration of anti-human lymphocyte globulin (AHLG), renal function improved, but urinary protein was still positive. Another patient had no episode of rejection during or after IFN alpha therapy.

Adult↗

PubMed1995

Effect of cigarette smoke on the mRNA and protein expression of carcinoembryonic antigen (CEA), a possible chemoattractant for neutrophils in human bronchioloalveolar tissues.

BACKGROUND: The concentration of carcinoembryonic antigen (CEA), known as a marker of malignant transformation and chronic inflammation, is increased in bronchoalveolar lavage fluid obtained from smokers compared with fluid from non-smokers. This study investigated the mechanism and biological significance of CEA production in the lungs of smokers by evaluating protein and mRNA expression in non-carcinomatous lung parenchymal tissues and in cell lines derived from human fetal lung. METHODS: Lung parenchymal tissue free from cancer or an inflammatory lesion was obtained from five non-smokers (four with lung cancer, one with pulmonary mycetoma), five ex-smokers (all with lung cancer except for one with mesothelioma), and 14 smokers (nine with lung cancer, five with emphysema) at surgery or necropsy. Cancer tissue was also collected simultaneously from the subjects with lung cancer. CEA protein in the tissue homogenates was measured by enzyme linked immunoassay. CEA mRNA expression in the non-carcinomatous parenchymal tissue and cancer tissue was evaluated by in situ hybridisation using CEA specific riboprobe and was semiquantitated by counting the number of silver grains per cell. CEA mRNA expression was also compared in three cell lines derived from human fetal lung (IMR-90, MRC-9, and CCD-14Br) after in vitro stimulation with medium exposed to cigarette smoke or air. Chemoattractant activity of purified CEA for neutrophils and monocytes was also studied in vitro. RESULTS: CEA content in non-carcinomatous lung tissue was increased in smokers with emphysema (mean (SD) 38.0 (9.2) ng/mg protein) or with lung cancer (38.2 (21.6)) compared with non-smokers (11.0 (5.4)) or ex-smokers (5.9 (2.2)). CEA mRNA expression in non-carcinomatous tissue, expressed by average number of grains per cell, was also increased in smokers with emphysema (mean (SD) 11.2 (4.1)) or with lung cancer (14.0 (8.4)) compared with non-smokers (3.1 (0.6)) or ex-smokers (4.0 (1.7)). CEA content in carcinomatous tissues was 42.8 (37.3) for non-smokers, 38.2 (42.4)) for ex-smokers, and 59.0 (22.5) for smokers. The CEA content in carcinomatous tissue was higher than in non-carcinomatous tissue, but there was no difference between non-smokers, ex-smokers, and smokers. The numbers of grains per cell in carcinomatous tissue were higher than in non-carcinomatous tissues, but not different among non-smokers (30.3 (3.9)), ex-smokers (38.3 (13.8)), and smokers (44.3 (5.2)). CEA mRNA expression in the cell lines was upregulated after the incubation with smoke-treated medium. Purified CEA was chemoattractant for neutrophils but not for monocytes in vitro. CONCLUSIONS: mRNA and protein expression of CEA were increased in the normal lung tissue from smokers compared with non-smokers or ex-smokers. Since CEA content and mRNA expression were no different between smokers with non-small cell lung cancer and those with non-carcinomatous disease, it is unlikely that CEA expression in non-carcinomatous lung parenchymal tissue was influenced by the presence of the tumour and is consistent with the effect of smoking. This is supported by in vitro studies which show that cigarette smoke could induce CEA mRNA expression in fetal lung derived cells. In addition, CEA might play a part in recruitment of neutrophils into the lower respiratory tract.

Aged↗

PubMed1995

[A case of post-biopsy arterio-venous fistula in a renal allograft].

We report here a case of post-biopsy arterio-venous fistula in a renal allograft which was successfully embolized. Percutaneous needle biopsy of renal allograft is performed when the cause of deteriorating renal function is clinically difficult to diagnose, and the pathological diagnosis obtained by it determines the therapy. An easy and safe biopsy encourages the clinician, but some complications occur after the procedure. Arterio-venous fistula is one of the complications after percutaneous needle biopsy of renal allograft. Color-coded ultrasonography is effective to find it, and transarterial embolization should be tried first to treat it.

Adult↗

PubMed1995

[A case of renal capsular liposarcoma].

A 53-year-old woman was admitted to the Department of Internal Medicine at our hospital with the primary complaint of pyrexia. Abdominal echography and computed tomography (CT) detected a right renal tumor, and the patient was transferred to our department. Angiography revealed a hypovascular tumor. The main nutrient vessels supplying the tumor were the superior and inferior capsular arteries, which arose from the renal artery. A right renal capsular tumor was suspected from these findings, and radical nephrectomy was performed. Histopathological examination revealed a pleomorphic liposarcoma. Therefore, the patient was given 50 Gy of radiation postoperatively. This is the 14th case of a primary liposarcoma of the renal capsule reported in Japan.

Female↗

PubMed1995

Shorter interval between cycles of cyclophosphamide, doxorubicin, cisplatin using recombinant human granulocyte colony-stimulating factor for urothelial cancer--phase I/II study.

BACKGROUND: Despite improvement in the response rate and protraction of the progression-free period of urothelial cancer produced by chemotherapy, severe bone marrow suppression often results in delays in the initiation of treatment cycles and/or decreases in drug dosages. Reduction of leukopenia during chemotherapy has been demonstrated by the combined administration of granulocyte colony-stimulating factor (G-CSF) in various malignancies. METHODS: A phase I/II study was conducted to assess whether the interval between cycles of CISCA (cyclophosphamide, doxorubicin, cisplatin) chemotherapy could be shortened under support of recombinant human granulocyte colony-stimulating factor (rhG-CSF) for urothelial cancer. Three or more patients with transitional cell carcinoma of the urinary tract were allocated to each of four different treatment intervals (step 1: 28 days, step 2: 21 days, step 3: 17 days, and step 4: 14 days) by reducing the interval in a step-wise manner. Two mg/kg/day of a rhG-CSF, lenograstim, was injected subcutaneously on days 3 to 16 (until day 14 for the 14-day interval group). RESULTS: Sixteen patients were enrolled, four patients were treated with the step 1 protocol, five with step 2, four with step 3, and three with step 4. Leukopenia/neutropenia was the most severe toxic reaction, but none of the patients at any step manifested neutropenia of WHO grade 4 for more than four days. There were no significant differences in the hematological and nonhematological toxicities among the 4 steps. Seven of eight patients with measurable diseases were treated with CISCA on shortened schedules (steps 2-4), and one complete remission (CR) and four partial responses (PR) were demonstrated. CONCLUSIONS: CISCA chemotherapy supported by rhG-CSF was safely shortened to a 14-day interval in the pilot study. The potential role of rhG-CSF in shortening the interval of CISCA, as well as the benefit of the intensified schedule, remains to be clarified.

Adolescent↗

PubMed1994

The augmented rectal bladder for urinary diversion: experience with the original valved rectum and a valve-less modification.

Kock's augmented and valved rectum was created in 10 patients following total cystectomy. During an observation period of up to 46 months, 4 patients died (1 from a recurrence of cancer, 1 from multiple organ failure subsequent to diabetes mellitus, 1 from coronary insufficiency, and 1 from cerebral hemorrhage). Post-operative complications included valve failure in 1, hydronephrosis in 2, and mild nocturnal urinary incontinence in another. Hyperchloremic metabolic acidosis was particularly notable in the cases without an intussuceptive valve of the rectum. Their base excess ranged from -6.9 to -15.0 mM/l but the condition was satisfactorily controlled by oral administration of alkaline agents. Although the present method has a number of shortcomings, the absence of a stoma and elimination of the need for self-catheterization are outstanding benefits. For these reasons, we believe that it is an effective option for urinary diversion.

Aged↗