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Biomedical subjects

M Iguchi

Publications and source records attributed to M Iguchi.

At least 109 records · Page 6Linked to original sources

Homeostasis as regulated by activated macrophage. V. Suppression of diabetes mellitus in non-obese diabetic mice by LPSw (a lipopolysaccharide from wheat flour).

A lipopolysaccharide from wheat flour (LPSw) which was isolated and characterized is shown to exert definitely a suppressive effect on incidence of type 1 diabetes in mice. Therapeutic effect on type 2 diabetes in patients was also obtained, though only from preliminary results. The percutaneous route of administration is most favorable. The important role that precursor tumor necrosis factor, free or cell bound, may play in this mechanism is discussed.

Animals↗

Homeostasis as regulated by activated macrophage. I. Lipopolysaccharide (LPS) from wheat flour: isolation, purification and some biological activities.

Based on our new concept of ontogenic inflammation, we have sought a substance which can prime macrophage in terms of the endogenous production of tumor necrosis factor (TNF). A lipopolysaccharide (LPSw) was found in wheat flour, purified and characterized. The molecular size of LPSw was about 5 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and it contained 3-deoxy-D-manno-octulosonic acid: 1, hexosamine: 4 and one phosphorus in a single molecule. LPSw can prime macrophage to release TNF when given intradermally, percutaneously or even orally in mice as well as in humans, in exactly the same way as intravenous administration of interferon gamma.

Administration, Oral↗

Homeostasis as regulated by activated macrophage. III. Protective effect of LPSw (lipopolysaccharide (LPS) of wheat flour) on gastric ulcer in mice as compared with those of other LPS from various sources.

Protective effect of lipopolysaccharide (LPS) from various sources on gastric ulcer has been examined in mice using parenteral as well as oral route. Ulcer is induced by indomethacin, stress or alcohol. LPS was prepared from 6 species of bacteria (Escherichia coli, Pantoea agglomerans, Serratia ficaria, Enterobacter cloacae, Bordetella pertussis, Alcaligenes faecalis) and from wheat flour. When administered intravenously, LPS of Pantoea agglomerans was the most effective among other LPS examined. Lipopolysaccharide of wheat flour (LPSw) showed a significantly protective effect by the oral route, especially when given ad libitum in drinking water to mice.

Animals↗

On the mechanism of papaverine inhibition of the voltage-dependent Ca++ current in isolated smooth muscle cells from the guinea pig trachea.

The effects of papaverine, a smooth muscle relaxant agent, on the voltage-dependent Ca++ current were examined in isolated smooth muscle cells from the guinea pig trachea. The tight-seal whole cell voltage clamp technique was used. Papaverine (1-100 microM) inhibited the Ba++ inward current (IBa) through the voltage-dependent L-type Ca++ channel in a concentration-dependent fashion. The inhibitory effect of papaverine on IBa appeared to have both tonic and use-dependent components. In addition to the reduction of the maximal conductance of IBa, papaverine (20 microM) shifted the quasi-steady-state inactivation curve of IBa to more negative membrane potentials by approximately 10 mV. These effects of papaverine on IBa were completely reversible. Although it has been suggested that papaverine inhibited phosphodiesterase to increase intracellular cyclic AMP, phosphodiesterase inhibitors (theophylline, 500 microM, and 3-isobutyl-1-methylxanthine, 500 microM), isoproterenol (2 microM) and dibutyryl cyclic AMP (1 mM) did not affect IBa. Thus, papaverine inhibits IBa in a way independent of intracellular cyclic AMP. Papaverine also had inhibitory effects on other membrane currents (i.e., the voltage-dependent transient outward K+ current and the Ca(++)-activated oscillatory K+ current), which may result in an enhancement of the excitability of the cells. These results suggest that inhibition of the voltage-dependent L-type Ca++ channel is involved in the papaverine-induced relaxation of the tracheal smooth muscle.

Animals↗

Coenzyme Q10 attenuates cyanide-activation of the ATP-sensitive K+ channel current in single cardiac myocytes of the guinea-pig.

The effect of coenzyme Q10 (CoQ10) on the cyanide (CN-)-induced ATP-sensitive K+ channel current (KATP) was examined in single atrial myocytes, using the patch clamp technique. Superfusion of the cells with a CN-/low glucose bathing solution induced an outward current in the whole-cell clamp condition. Glibenclamide (1 microM) abolished this current, indicating that the current was carried through the KATP channel. After steady-state activation by CN-, pinacidil (a KATP channel opener, 300 microM) failed to further increase the current. In cell-attached patches, CN-, when applied to the bath, induced bursting openings of an 80 pS channel (the KATP channel). In cells preincubated for 30 min in a solution containing CoQ10 (100 micrograms/ml), CN(-)-activation of the KATP channel was markedly attenuated both at the whole cell and at the single channel level. At the steady-state effect of CN- in CoQ10-treated cells, pinacidil (300 microM) activated the current to the maximum level achieved by CN- in the control cells. These results suggest that CoQ10 reduces in the CN(-)-induced KATP current not by affecting the channel itself but by preventing depletion of intracellular ATP caused by CN-.

Adenosine Triphosphate↗

Relationship between metabolic acidosis and calcium phosphate urinary stone formation in women.

The relationship between the degree of metabolic acidosis and calcium phosphate stone formation was studied. Furthermore, the reasons why renal tubular acidosis (RTA) and primary hyperparathyroidism (PHPT) dominantly occur in women, and female stone formers more often produce calcium phosphate stone are discussed. Blood was slightly more acidotic in women than in men in both the urolithiasis and the control groups. Likewise, blood was significantly more acidotic and urinary pH significantly higher in patients with PHPT. Patients with RTA had severe metabolic acidosis, and urinary pH was highest among all groups. Calcium phosphate concentration was significantly higher in women than in men, and was also higher in patients with PHPT than in those with urolithiasis. All patients with RTA had pure calcium phosphate stones. The reasons why females are more acidotic and have more calcium phosphate in stones are suspected to be related to progesterone and urinary tract infection.

Acidosis, Renal Tubular↗

Epidemiology of urolithiasis in the elderly.

To estimate the epidemiology of upper urinary stones in the elderly, a total of 1,957 patients (1,349 men and 608 women) with urolithiasis were studied. The ratio of men to women was approximately 3:1 in middle-aged (between 30 and 59 years), 1:1 in young (29 or younger) and 1:1 in old patients (60 or older). Compared with the age distribution of the entire Japanese population, the incidence of urinary stones was very low in both male and female children, twice as high in middle-aged men, slightly higher in middle-aged women, and equal or slightly lower in the male and female elderly. Stones of calcium oxalate and uric acid occurred more frequently and those of calcium phosphate and struvite less frequently in men than in women. This tendency was especially obvious in the middle-aged. In the old generation, calcium oxalate stones occurred almost equally in men and women. Results of urinary stone analysis were similar among men of the three generations, although the incidence of uric acid stones increased with patient age. In women, however, the incidence of calcium oxalate was higher in the young and old generations, while that of calcium phosphate was higher in the middle-aged.

Adolescent↗

Simple tests to determine urinary risk factors and calcium oxalate crystallization in the outpatient clinic.

We developed 2 simple and rapid tests for measurement of constituent concentrations and the stone-forming tendency of urine in the outpatient clinic. The concentrations of urinary constituents of calcium, magnesium, phosphorus, uric acid and oxalic acid were measured using 2 types of simple colorimetric tests (vial and quantitative filter types). The intensity of the color developing after a given interval was compared with a color standard of 4 levels. The results obtained using the colorimetric test were slightly lower in value than but significantly correlated with those obtained with standard measurements. The second test measured the crystal-forming ability of urine. A 10 ml. urine sample was pipetted into 4 vials that each contained different concentrations of oxalic acid and calcium. After a given interval the turbidity in each vial was compared with a control (0 mg. oxalic acid and calcium). If turbidity occurred in urine with low concentrations of oxalic acid and calcium the sample had a large tendency for crystals to form.

Ambulatory Care↗

Malignancy associated with chronic empyema: radiologic assessment.

Radiologic findings of six cases of malignancy associated with chronic empyema 5-39 years in duration were reviewed. Pathologic examination confirmed three B-cell non-Hodgkin lymphomas, one round-cell sarcoma, one mesothelioma, and one adenocarcinoma. Retrospective findings on plain chest radiographs suggested the occurrence of malignancy: increased radiopacity in the thoracic cavity, soft-tissue bulgings and/or unsharpness of fat planes in the chest walls, destruction of bone near the empyema, and extensive medial deviation of the calcified pleurae. Computed tomography delineated masses with soft-tissue attenuation more clearly than radiography in all cases. Magnetic resonance images of three cases were informative because empyema cavities were surrounded by low-intensity rims, and two of them showed a signal intensity different from that of necrotic tumors. Scintigraphy revealed increased uptake of gallium in all cases. Ultrasonography was useful for biopsy guidance. Every radiologist should know this entity in observation of chest radiographs obtained in patients with chronic empyema, and further radiologic assessment and aggressive biopsy are recommended if malignancy is suspected.

Adenocarcinoma↗

Assessment of the long-term results of ileocecal conduit urinary diversion.

We reviewed our 12.5-year experience with ileocecal conduit (ICC) and report the long-term results of 147 cases of ICC compared with those of our 102 cases of ileal conduit (IC). We usually performed ICC following total cystectomy for carcinoma of the bladder, while we chose IC in cases of high stage or recurrent malignancies. The average follow-up period was 41.7 months in the ICC group and 28.8 months in the IC group. The postoperative mortality (6.1%) and the incidence of early complications (21.1%) in the ICC group were comparable with the reported incidences for IC. In the later period, stomal problems were most frequently encountered. Urinary tract complications are important because they affect renal function in the course of a long period of time. Excretory urogram showed a satisfactory result and serum creatinine remained within the normal limits even in patients followed up for a long time in both groups. The incidences of pyelonephritis and urinary stones in the ICC group were 13.6 and 5.4%, respectively. We had expected a much lower incidence of these complications and ICC could not cover all the drawbacks of IC. However, at present, there is no ideal or perfect method of urinary diversion, ICC should be one of the acceptable options which has a satisfactory long-term result.

Adolescent↗

Characteristics and usage of different ureteral stent catheters.

Presuming that complications associated with ureteral stenting vary in type and occurrence depending on the material and cross-section of the stent, six types of stents immersed in 48 different preparations of artificial urine for 1 month to observe surface changes with a scanning electron microscope. As a result, there was less encrustation on the silicone material compared with other material types, probably due to the smoothness of the surface. This may be related with higher frequency of spontaneous removal or migration to the bladder of this catheter type. Because silicone catheters have softer and thicker walls with a narrow lumen, they may be appropriate for long-term stenting, but not for urinary drainage. In alkaline bacteriuria, struvite encrustation was observed on all stents. This reaction was especially intense with Towers peripheral stents, which had most irregular and uneven surfaces. In aseptic alkaline urine, calcium phosphate crystals partly covered with proteinaceous debris were noted on catheter surfaces. Although in some patients encrustation of uric acid occurred in the bladder portion of the stents, there was no uric acid encrustation in this experimental study.

Crystallization↗

[The anticancer effects of high energy shock waves on rat bladder cancer induced by BBN].

The in vivo anticancer effects of high energy shock waves (HESW), on bladder cancer induced by N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN), were studied in the rat using the Siemens lithotriptor (Lithostar). There was no significant difference in the anticancer effects in delaying tumor growth, measured as the whole bladder weight including the weight of the cancer, between the groups with and without exposure to HESW. However, light microscopic examination revealed extensive submucosal bleeding and exfoliation of mucosa, and electron microscopic examination revealed degeneration of pleomorphic microvilli, swelling of mitochondria, and destruction of mitochondrial cristae in the cancer cells in bladders exposed to HESW. Flow cytometric determination of DNA content in the cancer cells exposed to HESW indicated a selective diminution of cells in the G2 and M phases and an increase of cells in the G0 and G1 phases of the cell cycle. While the mechanism of HESW-induced anticancer effect could not be determined on the basis of this study, these changes in the morphology and the cell cycle of cancer cells induced by HESW exposure suggest some kind of biological effects following exposure to HESW. It is expected that HESW be an effective method for the treatment of human cancer in combination with chemotherapy and radiation.

Animals↗

[Studies on renal damages after extracorporeal shock wave lithotripsy using Gd-DTPA-enhanced dynamic MRI].

Renal damages after ESWL treatment were examined by Gd-DTPA enhanced dynamic MRI. Gd-DTPA was used as the contrast medium and fast magnetic resonance imaging with suspended respiration using the flip angle of 20 degrees and gradient echo technique at 0.5 Tesla was used for photographing. In normal kidneys, a low intensity band was observed with the passage of Gd-DTPA through the kidney from 1 to 2 minutes after the injection. In patients who underwent ESWL treatment, however, the low intensity band which was observed before ESWL treatment became partly obscure after ESWL treatment. Furthermore, these find changes in the renal parenchyma could not be fully detected by usual MRI which does not use Gd-DTPA. Gd-DTPA enhanced dynamic MRI was considered to be effective for finding the limited dose of shock waves for ESWL treatment.

Adult↗

[Preparation of a standard diet for out-patients in the study of lithogenesis].

With the development of extracorporeal shock wave lithotripsy treatment, the duration of hospitalization for stone patients fortunately has become shorter. However, a detailed analysis of lithogenesis is not possible during such patients' short hospital stays. We prepared a standard diet to be eaten at home for investigation of lithogenesis at the out-patient clinic. This diet was nutritionally well-balanced and contained the following: energy: 2000 Kcal, total protein: 70-75 g, animal protein: 30-35 g, carbohydrate: 510 g, fat and oil: 50-60 g, calcium: 600-630 mg and magnesium: 320 mg. The urine of 24 male patients with stones on a free diet and the same patients after 3 days on the standard diet was analyzed for urea-nitrogen, uric acid, sodium, calcium, phosphorus, magnesium, citric acid and oxalic acid. The results were compared with those in 17 healthy male subjects who were eating the standard diet (controls). It was found that 66% of hypercalciuria (greater than = 300 mg/day) on a free diet became normocalciuria on the standard diet. The hypercalciuria was therefore thought to be of dietary origin. Moreover, urinary excretion of urea nitrogen, uric acid, sodium and phosphorus by patients remarkably decreased after 3 days on the standard diet, which was not different from that of controls. These results suggest that the standard diet at home is useful in the screening of hypercalciuria and also quite adequate for patients with stones.

Adult↗

[AIH in male infertility due to retrograde ejaculation after retroperitoneal lymph node dissection].

A patient with testicular cancer (non-seminoma, stage IIB) who had undergone resection for primary disease and retroperitoneal lymph node dissection as well as chemotherapy and radiotherapy 6 years before developed iatrogenic retrograde ejaculation. The infertility was treated by oral medications, including herbal medicine and injections of a hormone preparation as well as artificial insemination of husband (AIH). After 24 sessions of AIH for 4 years, his spouse gave birth to a healthy baby girl. We believe that for patients with iatrogenic retrograde ejaculation AIH is an effective method of increasing fertility to be employed more often.

Adult↗

[Studies on calcium oxalate crystal formation in urolithiasis. Multi-regressive analysis of urinary CaOx crystalline volumes and the effects of urinary various substances on CaOx crystal formation].

Because human urine contains various substances which can affect each other, it is quite difficult to clarify the mechanism of formation of calcium oxalate (CaOx) crystal in urine. The authors recently determined CaOx crystalline content and the concentrations of other substances in urine specimens from patients with urolithiasis and healthy volunteers, and subjected the data to multi-regressive analysis for the purpose of assessing the effect of these urinary substances on CaOx crystal formation. 1. In analysis of urine from patients with urolithiasis, the partial correlation coefficients of CaOx crystal formation with oxalic acid, sodium, calcium, uric acid magnesium were 0.67, 0.28, 0.18, and -0.10, respectively. The formula of regression was as follows: Amount of CaOx crystal (X 10(6) microns3/ml) = 3.59 X 10(-2) Ox (mM/L) + 4.72 X 10(-3) Ca (mM/L) + 4.52 X 10(-3) Na (mM/L) + 2.51 X 10(-4) UA (mM/L) -2.39 X 10(-2) Mg (mM/L) -1.65. The multiple correlation coefficient was 0.759. Thus, in patients with urolithiasis, urinary crystal formation was most dependent on the oxalic acid level, sodium, calcium, and uric acid were found to promote crystal formation, while magnesium to suppress it. 2. In analysis of urine from healthy volunteers, the partial correlation coefficients of CaOx crystal formation with oxalic acid and inorganic phosphorus were 0.51 and -0.24, respectively. The formula of regression was as follows: Amount of CaOx crystal (X 10(6) microns3/ml) = 1.91 X 10(-2) Ox (mM/L) -3.43 X 10(-4) P (mM/L) +0.29 The multiple correlation coefficient was 0.525.(ABSTRACT TRUNCATED AT 250 WORDS)

Calcium↗

[The effectiveness of prophylactic dietary treatment in renal stones].

By following individual dietary guidelines which were established from analysis of the dietary intake and habits of male renal stone patients, the stone recurrence rate in 75 male calcium stone patients who had only received individual dietary instruction decreased markedly, as compared with that in 114 male calcium stone patients who had not received such instructions. Among 75 patients, recurrence was noted in 6 normocalciuric recurrent stone patients and 1 normocalciuric single stone patient during the period of outpatient visits. Investigation of the daily consumption of various nutrients and urinary excretion revealed no differences among the 6 normocalciuric recurrent stone patients, hypercalciuric recurrent stone patients, hypercalciuric single stone patients and normocalciuric single stone patients. Our findings suggest that the high recurrence rate in the normocalciuric recurrent stone patients is associated with stone lithogenic factors, such as heredity and anatomy, that could not be controlled by the daily treatment in this group.

Adolescent↗

[Indications for surgical treatment of secondary hyperparathyroidism].

From 1978 to 1990 subtotal parathyroidectomy was carried out on 41 patients for secondary hyperparathyroidism. The indications for parathyroidectomy and suitable operative time, especially in the point of view of renal osteodystrophy are discussed. Serum ALP and PTH level and the presence of generalized fibrous osteitis were good indicators for parathyroidectomy. Furthermore, 99mTc-Pyrophosphate bone scintigraphy and Dual Photon Absorptiometry were proved to be valuable for patient selection for parathyroidectomy. Parathyroidectomy for patients in whom 99mTc-pyrophosphate bone uptake is diminished or patients in whom bone mineral contents are dramatically decreased must be carefully performed.

Absorptiometry, Photon↗