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Biomedical subjects

H Baba

Publications and source records attributed to H Baba.

At least 325 records · Page 18Linked to original sources
PubMed1992

Mechanism of relaxation induced by K+ and nicotine in dog duodenal longitudinal muscle.

Dog duodenal longitudinal muscle strips precontracted with bradykinin responded to K+ (10 mM) with a transient relaxation, which was abolished by tetrodotoxin and oxyhemoglobin, but not influenced by atropine, ouabain and apamin. The induced relaxation was suppressed by treatment with 10(-5) M NG-nitro-L-arginine (L-NNA) a nitric oxide synthesis inhibitor, but not by the D-enantiomer. The inhibitory effect was antagonized by L- but not D-arginine. High concentrations (20 mM or higher) of K+ produced a relaxation followed by a sustained contraction; nicardipine abolished the contraction, but did not alter the relaxation. Nicotine produced a contraction, which was converted to a relaxation by atropine. The relaxant response was abolished by tetrodotoxin, hexamethonium and oxyhemoglobin, but was unaffected by timolol and phentolamine. L-NNA suppressed the relaxation, and L-arginine reversed the inhibition. The addition of K+ (20 mM) increased the content of cyclic GMP in the strips, the effect being prevented by tetrodotoxin and L-NNA. These findings suggest that K+ selectively stimulates the nonadrenergic inhibitory nerve, whereas nicotine stimulates both the excitatory cholinergic and inhibitory nerves. Nitric oxide released from the inhibitory nerve appears to transmit information to duodenal smooth muscle by increasing the production of cyclic GMP.

Adenosine Triphosphate↗
PubMed1992

Hyperamylasemia associated with lymphadenectomy in patients surgically treated for gastric cancer.

The influence of standard lymphadenectomy on the occurrence of damage to the pancreas was evaluated in 28 patients with gastric cancer, by analysing related serum and urine enzyme activities, pre- and postoperatively. Enzymatic evidence for pancreatic damage was related to the surgical procedure performed. Postoperatively, the patients treated by R2 gastrectomy had significantly increased levels of P-type amylase in the serum compared with findings in patients treated by R1 gastrectomy or bypass procedures. Conversely, the S-type amylase in both groups remained within normal limits during the study period. Pancreatic secretary trypsin inhibitor (PSTI) and phospholipase A2 (PLA2) proved to be less sensitive to pancreas damage caused by lymphadenectomy. The R2 patients with P-type hyperamylasemia had no major postoperative complications. Thus, while the standard R2 gastrectomy may well be a relevant factor associated with the occurrence of transient P-type hyperamylasemia, there seems to be no relation to major postoperative complications such as pancreatitis.

Adult↗
PubMed1992

[On the problems of the antituberculous drug resistance].

In this part, we will discuss exclusively about the technique of measurement. It is desirable especially for the proportion method that two inoculations with the same doses give the same number of colonies and when diluted, the colonies decrease exactly parallel to it degree of dilution. But this ideal is not necessarily realized and especially the difference between the dilution of 10(-3) and 10(-4) mg/ml on the drug free medium and that of 10(-2) and 10(-3) on the drug containing medium is fairly remarkable: the former is not so large but the latter sometimes varies tremendously with the drugs and their concentrations. So it is necessary to use always two inoculations for all specimens and the resistance is calculated on the medium inoculated with the same doses, for that, colonies on the control must be countable and suitable number that is 50-300. Further too concentrated solution like 10(-2) mg/ml must not be used for the proportion method. The selection of the most suitable two dilutions is specially important for this method. Original one is 10(-3) and 10(-5). Unfortunately we did not follow this formula and at first we adopted the combination of 10(-3) and 10(-4), then 10(-2) and 10(-4) finally 10(-2) and 10(-3) which was the worst. Now we searched for the dilution which gave the suitable number of colonies from our several thousand cases and found that 10(-4) was the most excellent and gave this number in 63%, next 10(-5) in 14%, and then 10(-3) in 7.2%, 10(-2) in only 1.0%. With the combination of 2 solutions 10(-3) and 10(-5)--original one--was most excellent (94.8%) then 88.4% with 10(-4) and 10(-5). The combination of 10(-2) and 10(-3) was worst, it gave only 8.9%. As the proportion method demands the most strict procedures for all cases, it is necessary as simplify as possible, thus in every day practice, only the drugs most frequently used (3 or 4 drugs) and one concentration for each drug could be examined. Further we discussed on the difference between DH-SM and SM, direct and indirect method and problem of plug.

Antitubercular Agents↗
PubMed1992

[Effects of timolol and carteolol on ocular pulsatile blood flow].

Effects of timolol (0.5%) and carteolol (2%) on ocular pulsatile blood flow (PBF) were studied in healthy adult volunteers. PBF was measured with the BFA system, analyzing the ocular pressure waves. Each drug was instilled in one eye and PBF was measured in both eyes before and fifteen minutes after the instillation. In each drug, the PBF change between the two measurements was evaluated with a control study, which was performed in the same manner with physiological saline solution. In the non-instilled eyes, both timolol (n = 6) and carteolol (n = 9) had no significant change on PBF. In the instilled eyes, timolol (n = 6) caused no significant change, whereas carteolol (n = 9) increased PBF significantly. The range of the BFA system measurement error was within 4.7 +/- 2.4 microliters/min (P = 95%). Taking the error into account in each instilled eye, timolol (n = 6) increased PBF in 3 eyes and decreased it in 3 eyes, while carteolol (n = 9) increased PBF in 7 eyes, did not change it in one eye and decreased it in one eye. It is thought the effect of carteolol to increase PBF may be explained by endothelium-dependent relaxing factor (EDRF).

Adult↗
PubMed1992

A simple procedure for intrahepatic biliary drainage in patients with obstructive jaundice owing to a recurrence of cancer following reconstructive gastric surgery.

We designed a simple and reliable method of intrahepatic biliary drainage for patients with obstructive jaundice owing to a recurrent gastric cancer. This approach can be used for selected patients treated by partial gastrectomy and reconstructive surgery, using the Billroth II procedure and antecolic anastomosis. Anastomosis between the intrahepatic bile duct and the afferent jejunal loop is performed at the anterior edge of the liver, thus facilitating the prevention of recurrence of jaundice caused by tumor infiltration. Application of this technique led to a long-term palliation, control of the jaundice and a fairly normal life.

Adult↗
PubMed1991

Expression of the large myelin-associated glycoprotein isoform during the development in the mouse peripheral nervous system.

The developmental maximum expression of the large myelin-associated glycoprotein isoform (L-MAG) protein prior to that of the small myelin-associated glycoprotein isoform (S-MAG) in both the central and peripheral nervous systems (CNS, PNS) in mice was shown by immunoblotting techniques using specific antibodies to the L-MAG protein and the S-MAG protein. Both the L-MAG protein and the S-MAG protein were expressed earlier in the PNS than in the CNS, which reflects earlier myelination in the PNS. The peak of the L-MAG protein concentration was 8 days in the sciatic nerve and 15 days in the brainstem. The concentration of the S-MAG protein in the sciatic nerve reached a peak at 15 days, whereas in the brainstem it increased rapidly between 15 and 20 days and gradually thereafter. Thus, the preceding maximum expression of the L-MAG during active myelination in the PNS demonstrated here as well as in the CNS strongly suggests an important role for L-MAG in myelin formation.

Aging↗
PubMed1991

Direct inhibitory effect of amino-terminal parathyroid hormone fragment [PTH(1-34)] on PTH secretion from bovine parathyroid primary cultured cells in vitro.

We have examined the possibility of direct inhibitory effect of PTH(1-34) on PTH secretion in bovine parathyroid cells. As low as 10(-12) M PTH(1-34) completely inhibited low calcium (0.5 mM Ca2+)-stimulated PTH secretion by these cells. In the presence of 1.25 mM Ca2+, 10(-12) M PTH(1-34) inhibited PTH secretion by about 14.3% of the basal value, while 10(-11) M or higher concentration of PTH(1-34) showed potent inhibitory effects equivalent to the inhibitory action of high calcium concentration (2.5 mM Ca2+) on PTH secretion. At 2.5 mM Ca2+, as much as 10(-9) M PTH(1-34) failed to inhibit PTH secretion further. These results suggest that PTH(1-34) might directly, not via calcium concentration, inhibit PTH secretion by parathyroid cells and that a cooperative mechanism could exist between calcium and PTH(1-34) to inhibit PTH secretion.

Animals↗
PubMed1991

Clinicopathologic features and prognostic significance of duodenal invasion in patients with distal gastric carcinoma.

Clinicopathologic features and prognostic significance of duodenal invasion were studied in a retrospective study on 593 patients who underwent gastrectomy for adenocarcinoma in the antrum. The patients were grouped into three, according to the histologic extent of duodenal invasion: Group A (80 patients), obvious invasion beyond the pyloric ring; Group B (61 patients), invasion up to the pyloric ring; and Group C (452 patients), no evidence of duodenal invasion. Five-year survival rates in Groups A, B, and C were 7.9%, 31.6%, and 57.6%, respectively (P less than 0.001). Cox's regression analysis showed that duodenal invasion is an independent prognostic factor in cases of a gastric antrum carcinoma. Gastric cancer with duodenal invasion (Groups A and B) most often was infiltrative and the incidence of serosal invasion, lymphatic and vascular invasion, and lymph node metastasis was high. Duodenal invasion was direct through submucosal or subserosal layers or through submucosal lymphatics.

Adenocarcinoma↗
PubMed1991

Protective effect of ICRF-187 against normal tissue injury induced by adriamycin in combination with whole body hyperthermia.

The use of [(+)-1,2-bis(3,5-dioxopiperazinyl-1-yl)]propane (ICRF-187) as a protective agent against normal tissue toxicity caused by combined Adriamycin (ADR) and whole body hyperthermia (WBH; 2 h at 41.5 degrees C) was assessed in a rat model. The effect of ICRF-187 on the antitumor response induced by the combination of ADR and WBH was also investigated in order to assess alterations in the therapeutic index of this combined therapeutic modality treatment. ICRF-187 significantly reduced ADR-mediated body weight loss, renal toxicity, and cardiomyopathy under both normothermic and hyperthermic conditions as shown by morphological and functional assays. ADR-induced neuropathy (seen only in normothermic rats) was also ameliorated by ICRF-187. Although this study did not show a pronounced effect of ICRF-187 on ADR-induced acute myelosuppression, ADR-mediated chronic anemia, leukocytosis, and thrombocytosis were reduced by ICRF-187 in both normothermic and WBH-treated rats. The effect of ICRF-187 on antitumor response was evaluated with a tumor growth delay assay using an in vivo transplantable fibrosarcoma. ICRF-187 caused no significant change in tumor growth delay induced by either ADR alone or ADR combined with WBH. Indeed, the only complete tumor regression following treatment resulted from the combination of ICRF-187 plus ADR plus WBH. Thus, ICRF-187 significantly increases the therapeutic index of the combined modality treatment of ADR and WBH by selectively reducing normal tissue toxicity without interfering with antitumor efficacy.

Animals↗
PubMed1991

Effect of adriamycin combined with whole body hyperthermia on tumor and normal tissues.

Thermal enhancement of Adriamycin-mediated antitumor activity and normal tissue toxicities by whole body hyperthermia were compared using a F344 rat model. Antitumor activity was studied using a tumor growth delay assay. Acute normal tissue toxicities (i.e., leukopenia and thrombocytopenia) and late normal tissue toxicities (i.e., myocardial and kidney injury) were evaluated by functional/physiological assays and by morphological techniques. Whole body hyperthermia (120 min at 41.5 degrees C) enhanced both Adriamycin-mediated antitumor activity and toxic side effects. The thermal enhancement ratio calculated for antitumor activity was 1.6. Thermal enhancement ratios estimated for "acute" hematological changes were 1.3, whereas those estimated for "late" damage (based on morphological cardiac and renal lesions) varied between 2.4 and 4.3. Thus, while whole body hyperthermia enhances Adriamycin-mediated antitumor effect, normal tissue toxicity is also increased, and the potential therapeutic gain of the combined modality treatment is eroded.

Animals↗
PubMed1991

Effect of carboplatin combined with whole body hyperthermia on normal tissue and tumor in rats.

The antitumor activity and normal tissue toxicity of cis-diammine-1,1-cyclobutane dicarboxylate platinum (II) (carboplatin) in combination with whole body hyperthermia (WBH) (41.5 degrees C, 120 min.) were examined in an F344 rat model. Carboplatin data were compared with those of cis-diamminedichloroplatinum (II) (cisplatin). At 37 degrees C, carboplatin showed minimal activity against a rat fibrosarcoma, but when combined with WBH, the antitumor effect-of the drug was greatly enhanced. The major carboplatin-induced acute toxicity at both normothermic and hyperthermic temperatures was marked hypocellularity of the bone marrow. A significant decrease in peripheral blood platelet counts was caused by the maximum tolerated doses (MTD) of carboplatin alone and with WBH. While the lethal dose of carboplatin alone caused only minimal renal damage, mild acute tubular necrosis was observed at the MTD of carboplatin with WBH, although no significant increase in blood urea nitrogen occurred. Therapeutic ratios of the combined chemotherapy and WBH modalities were calculated by comparing tumor growth response at the MTD of drug alone and drug combined with WBH. The combination of the nephrotoxic cisplatin with WBH resulted in a therapeutic ratio of only 0.8, whereas when carboplatin was combined with WBH, a value of 3.0 was obtained, representing a 3- to 4-fold increase over cisplatin in the therapeutic ratio. These data indicate that the less nephrotoxic carboplatin in combination with WBH improves therapeutic gain and may provide a more promising clinical combination for cancer treatment than cisplatin combined with WBH.

Animals↗
PubMed1991

Prognostic factors in Japanese patients with colorectal cancer: the significance of large bowel obstruction--univariate and multivariate analyses.

In order to define prognostic factors in colorectal carcinoma, univariate and multivariate analyses were carried out on data from 113 Japanese patients treated in a typical general hospital in Japan. In the univariate analysis, a poor prognosis was seen in those with poorly differentiated adenocarcinoma, in tumors that perforated the visceral peritoneum or that invaded directly other organs or structures (T4), in metastasis to the nodes along the main vascular pedicle (N3), in lymphatic permeation, in blood vessel invasion, in peritoneal dissemination, in Dukes C stage, and in those with lesions presenting with large bowel obstruction. Of these, only lymph node metastasis and peritoneal dissemination had an independent prognostic significance when a multivariate Cox analysis was performed. The significant risk factors related to an obstructing tumor were determined by multivariate logistic regression analysis. The significant variables were patient's age, nodal involvement and peritoneal dissemination. Since lymph node metastasis and peritoneal dissemination proved significant in both multivariate analyses, we propose that the presence of large bowel obstruction is not an independent prognostic factor in patients with colorectal carcinoma. In poor-risk patients who have an obstructing tumor, a staged operation should be attempted for definitive curative surgery.

Adenocarcinoma↗
PubMed1991

Comparison of R1 and R2 gastrectomy for gastric cancer in patients over 80 years of age.

To evaluate the benefit of R2 gastrectomy for gastric cancer in Japanese patients over 80 years of age, data on 93 patients who underwent gastrectomy between 1967 and 1989 were collected retrospectively from charts filed in the Kyushu University Hospital and two affiliated national hospitals. Of 93 patients, 62 had a localized tumor without evidence of metastatic spread. These 62 patients were classified into two groups according to the procedures performed: 35 underwent R1 gastrectomy and 27, R2 gastrectomy. The clinical and pathological characteristics of the patients in the two groups were comparable at the time of surgery, except that the group who underwent R1 gastrectomy was older. R2 gastrectomy involved a significantly longer operation time (P less than 0.01) and greater intraoperative blood loss (P less than 0.05) when compared to R1 gastrectomy, but no patient undergoing this extensive surgery died. The difference in the morbidity rate between the two groups was not statistically significant. The 5-year survival rate was 55.8% in the R1 group and 65.4% in the R2 group. When gastric cancer invaded the serosa and/or secondary nodes, a substantial increase in survival time was gained with R2 gastrectomy when compared to an R1 operation. These findings suggest that an R2 gastrectomy is feasible, even for patients over 80 years, but is indicated mainly when the carcinoma had invaded the serosa and/or secondary nodes and the patients are at good risk for major surgery.

Aged↗
PubMed1991

Antitumor activity of polymorphonuclear leukocytes activated by a beta-1,3-D-glucan.

The antitumor activity of mouse polymorphonuclear leukocyte (PMN) treated with a beta-1,3-D-glucan from Alcaligenes faecalis var. myxogenes IFO 13140 (TAK-N) and its carboxymethylated derivative (CM-TAK) was investigated in vitro and in vivo. ICR mouse PMN showed strong cytotoxicity against sarcoma 180 cells and inhibition of the growth of the tumor cells in vitro in the presence of TAK-N but not in the presence of CM-TAK. Since the cytotoxicity induced by TAK-N was almost completely inhibited by catalase, it seems to be mediated by H2O2 production by PMN. On the other hand, TAK-N induced no cytotoxicity in macrophages and neither did CM-TAK in PMN or in macrophage. Intraperitoneal injection of TAK-N into ICR mice induced a large number of PMN and macrophages in the peritoneal cavity. The peritoneal exudate PMN which were harvested at 10 to 72 h after TAK-N injection showed cytotoxicity against sarcoma 180 cells, but the peritoneal exudate macrophages did not. Treatment of sarcoma 180 ascites tumor-bearing ICR mice with TAK-N at a dose of 100 mg/kg prolonged significantly the survival time over that of the control. These results indicate that TAK-N induces PMN cytotoxicity against sarcoma 180 cells not only in vitro but also in vivo. The antitumor effect of TAK-N on sarcoma 180 ascites tumor seems to be derived from PMN stimulated with TAK-N.

Animals↗
PubMed1991

Suppression by NG-nitro-L-arginine of relaxations induced by non-adrenergic, non-cholinergic nerve stimulation in dog duodenal longitudinal muscle.

In dog duodenal longitudinal muscle strips, transmural electrical stimulation (10 Hz, 15 sec) elicited a transient contraction, which was abolished by tetrodotoxin and atropine but potentiated by treatment with NG-nitro-L-arginine (L-NA), a nitric oxide (NO) synthesis inhibitor. The potentiation was reversed by L-arginine but not by its D-enantiomer. Acetylcholine-induced contractions were not influenced by L-NA. After treatment with atropine, the electrical neural stimulation relaxed the muscle strips partially contracted with bradykinin, the relaxation being abolished by tetrodotoxin and suppressed by L-, but not D-, NA. L-arginine reversed the L-NA-induced inhibition. Oxyhemoglobin abolished the relaxation caused by nerve stimulation and NO. The neurally-induced relaxation was not attenuated by adrenoceptor antagonists and indomethacin. It is concluded that electrical stimulation of non-adrenergic, non-cholinergic nerves relaxes dog duodenal smooth muscle, due possibly to NO produced upon neural excitation, and potentiation by L-NA of the contractile response to cholinergic nerve stimulation, would be derived from elimination of the neurally-induced relaxation.

Animals↗
PubMed1991

[A case of spinal osteomyelitis detected by MRI].

A 75-year-old man was admitted because of chest pain and gait disturbance. He noticed pain in the left anterior chest regardless of exercise 3 months prior to admission. Two months later, the chest became smart with motion, followed by sensory disturbance of the lower extremities. On admission, he was anemic. His lower extremities showed exaggerated deep tendon reflexes with positive Babinski signs and an impairment of superficial and deep sense with sensory ataxia. Muscular weakness, muscular wasting, or urinary disturbance was not found. An X-ray film of his thoracic spine disclosed compression fracture and protein content of his cerebrospinal fluid was increased. Magnetic resonance image (MRI) of the ill spines revealed fusion of the bodies of the fifth and sixth thoracic vertebrae with a low signal intensity on T1-weighted images and a partially high signal intensity on T2-weighted images. The intervertebral disc was destroyed. Although histological or bacteriological confirmation was absent, characteristic MRI findings were compatible with spinal osteomyelitis. After antibacterial chemotherapy, his clinical symptoms improved and he came to be able to walk again.

Aged↗