Biomedical subjects
Publications and source records attributed to M Nishiki.
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Immunoreactive galanin and galanin message associated peptide (GMAP) were detectable in rat hypothalamus in the concentration of 563 +/- 23 and 14.3 +/- 3.1 fmol/hypothalamus, respectively. gamma-Aminobutyric acid (GABA) elicited a dose-related increase in galanin release from rat hypothalamic fragments, which was inhibited by picrotoxin, a GABA antagonist. Growth hormone (GH) secretion from rat anterior pituitary cells were stimulated by rat galanin, but not by GMAP. These findings suggest that hypothalamic galanin, but not GMAP, may play roles in GH secretion induced by GABAergic mechanisms in the rat.
A simulation study of distal interlocking of an intramedullary nail was performed using newly devised, portable stereo fluoroscopy. Two intramedullary nails in which ten holes were drilled perpendicular to the long axis and at various angles to the diameter were inserted into a femoral and a tibial bone model. Ten drill bits were drilled freehand into the holes in the nail with the aid of the stereo fluoroscope. All twenty drill bits were seated in the holes in the first attempt. This instrument provides a three-dimensional view in real time, which enables the surgeon to appreciate the three-dimensional relationship between the drill bit and the hole in the nail in the bone model. Distal interlocking of the intramedullary nail is facilitated with the aid of this stereo fluoroscope.
To establish a method of evaluating propolis, the effects of the ethanol and water extracts from various collecting of propolis from different countries and plant sources on hyaluronidase activity were investigated along with their absorption spectra and specific absorbance (E(1%)1 cm value). The relations between the hyaluronidase inhibitory activities of these extracts and their E(1%)1 cm values were also examined, and the following was found: 1) the enzyme inhibitory activities of the ethanol extracts were more potent than those of the water extracts; 2) the enzyme inhibitory activities of the ethanol extracts from Araucaria angustifolia (BERT.) O. KTZE were low compared with those of other ethanol extracts; 3) the enzyme inhibitory activities of all the ethanol extracts correlated excellently with their E(1%)1 cm values, but in the water extracts, they decreased with increase in E(1%)1 cm values; 4) the water extracts of Chinese propolis from Hebei, Jiangsu, Sichuan and Zhejiang Provinces inhibited weakly compared with that from Brazilian and other Chinese propolis; 5) the shapes of absorption bands of the propolis extracts and the E(1%)1 cm values were approximately dependent on the place or the plant source from which propolis was collected. These experimental results indicated that, for the exact evaluation of propolis, the enzymatic method, measuring the hyaluronidase inhibitory activity, was superior to the physicochemical method.
We studied functional and histopathological changes in acromegalic cardiomyopathy following intermittent subcutaneous infusion of octreotide. A 68-year-old female patient with acromegaly associated with congestive heart failure due to dilated cardiomyopathy was initially treated with cardioactive medication for three months, but it was not effective in correcting echocardiographic abnormalities. Further treatment with intermittent subcutaneous infusion of octreotide (20 microg/2 h) for 12 months not only reduced circulating GH and insulin-like growth factor-I (IGF-I) levels but also considerably improved histopathological changes in the myocardial specimen biopsied. These findings provide the first evidence of the favorable effect of octreotide on histopathological changes in acromegalic cardiomyopathy.
Pituitary adenylate cyclase-activating polypeptide-38 (PACAP-38) stimulated GH secretion in superfused rat anterior pituitary cell in vitro and in conscious male rats in vivo. PACAP-38-induced GH secretion was inhibited by PACAP-(6-38), an N-terminal-deleted analog, at 100-fold concentrations of PACAP-38 both in vitro and in vivo. In contrast, a GH-releasing hormone antagonist did not affect the action of PACAP-38 to stimulate GH release in vitro. Plasma GH increase induced by i.v. injection of 5-hydroxy-L-tryptophan (1 mg/100 g BW), a precursor of serotonin, was blunted by PACAP-(6-38) (1 nmol/100 g BW, i.v.), whereas spontaneous pulsatile GH secretion in conscious male rats, which is governed by hypothalamic GH-releasing hormone and somatostatin, was not affected by repeated i.v. injection of PACAP-(6-36). These findings suggest that PACAP-(6-38) is a potent antagonist of PACAP-38 to stimulate GH secretion both in vivo and in vitro. Taken together with the facts that PACAP-38 is highly concentrated in the hypothalamus and that is released into the hypophysial portal blood, our present findings suggest that PACAP-38 might play a stimulatory role on GH secretion induced by serotoninergic mechanisms in the rat.
The freeze-dried ternary formulations of meclizine (MZ, an anti-motion sickness drug), prednisolone (PRED, an anti-inflammatory drug) and norfloxacin (NFLX, an anti-microbial drug) which are poorly water-soluble and are low bioavailability drugs, were prepared using egg albumin and olive oil. The powder X-ray diffractions, the dissolution rate and the bioavailabilities in vivo of these formulations were studied in comparison with each drug alone. By forming ternary formulations of these drugs, the dissolution rates of the drugs from the formulations were significantly improved compared with each drug alone. The results of their powder X-ray diffraction measurements showed that these drugs in the ternary formulations presented in an amorphous form, indicating increased dissolution rates. On the other hand, the plasma concentrations of these drugs increased significantly after oral administration in formulations to rats, except for the NFLX formulation, and the areas under the concentration-time curves (AUC) of the ternary formulations of MZ, PRED and NFLX were 2.1, 1.6 and 1.3 times those of the drugs alone, respectively. From these results, it was proven that formulations consisting of egg albumin, olive oil and poorly water-soluble drugs were useful preparations for improving the drug's disadvantageous pharmaceutical properties.
The effects of tamoxifen (TAM), medroxyprogesterone acetate (MPA), their simultaneous combination or an alternating sequential combination of TAM plus MPA (TAM-MPA), was evaluated in 52 patients with advanced or recurrent breast cancer in a randomized controlled trial. The response rates of TAM, MPA, TAM & MPA, and TAM-MPA were 13.3%, 36.4%, 7.1% and 25.0%, respectively. All four therapies showed a higher response rate in the patients with soft tissues or with no previous therapy. However, there were no significant differences between the patient's characteristics and response rate among these four therapies. The differences in the frequency of adverse effects among these therapies were not significant, and there were no severe adverse effects with any therapy. In the cross-over trial of TAM and MPA, although 15.4% of patients who failed to show a response to TAM showed an objective response to MPA, no response to TAM was seen in the patients who had failed to show a response to MPA. In conclusion, TAM & MPA was not more effective than TAM or MPA, and TAM-MPA was not more effective than MPA. Adverse effects were not increased with TAM & MPA or TAM-MPA. MPA was useful as a second-line therapy after TAM.
The known salient features of spinal cord injuries in children are that 1) plane X-rays may not show dislocations or fractures, 2) many of these injuries are complete transections, 3) many injuries are located at the level of upper thoracic spine, and 4) the duration of spinal shock is short. Complications such as pressure sores occur just as easily in children as in adults and the injuries tend to be just as intractable. Complications characteristic in children with spinal cord injuries are spinal deformity and hip dislocation. In this paper, we describe a case involving a C7 spinal cord injury caused by a fall when the patient was 3 years old. We have observed the physical complications for 15 years following that injury. We also report on other observed cases of spinal cord injury.
Effect of pituitary adenylate cyclase-activating polypeptide (PACAP) on prolactin (PRL) secretion was studied in Wistar strain male rats in vivo. Intravenous injection of PACAP-38 and PACAP-27 resulted in a dose-related increase in plasma PRL levels both in conscious rats and in urethane-anesthetized rats. In anesthetized animals, i.c.v. injection of PACAP-38 and PACAP-27 also elicited a dose-related increase in plasma PRL. The PRL secretion induced by i.c.v. injection of PACAP-38 was attenuated by pretreatment with rabbit antiserum to vasoactive intestinal polypeptide (VIP). These findings suggest that PACAPs stimulate PRL secretion in the rat by acting not only directly on the pituitary but also indirectly through the central nervous system, at least partly, via hypothalamic VIP.
Effect of pituitary adenylate cyclase activating polypeptide (PACAP) on growth hormone (GH) release from GH3 cells was studied in a dynamic superfusion system. PACAP-38 and PACAP-27 stimulated GH release from superfused GH3 cells. The stimulatory effect of PACAP-38 was comparable to those of vasoactive intestinal polypeptide (VIP) and PACAP-27 at a concentration of 1 nM, but the duration of action was more prolonged in PACAP-38 than in the other two peptides. PACAP(6-38), a selective antagonist of PACAP, as well as a VIP antagonist blunted the GH release induced by PACAP-38 and VIP. An antagonist of GH-releasing factor (GRF) at a concentration of 1 microM, however, did not affect the GH release induced by PACAP-38. These findings suggest that PACAP and VIP stimulate GH release from GH3 cells through type II PACAP receptor but not through the GRF receptors.
BACKGROUND: Nine patients with a history of radical nephrectomy for renal cell carcinoma underwent surgical removal of newly detected pulmonary nodules at the Hiroshima University Hospital. Six patients had metastatic lung tumors two patients had bronchogenic primary carcinomas and one had a granulomatous infection. METHODS: To determine if any characteristics can distinguish a new primary carcinoma from metastatic renal cell carcinoma, we reviewed the nine patients described above. The patients with pulmonary metastases and those with new primary lung cancers did not differ in age, sex, history of smoking, clinical stage and pathological findings of the renal primary site, on the location and size of the pulmonary nodules. RESULTS: Only the interval between the nephrectomy and the appearance of the new pulmonary lesion may be a predictive factor. This interval was 48 and 51 months for the patients with new primary lung cancers but varied from 0 to 39 months for the patients with metastatic renal cell carcinoma. A solitary nodule had an equal chance of being metastatic or primary. CONCLUSIONS: These results indicate that a solitary nodule that is detected at a longer interval after radical nephrectomy may be a new primary lung cancer. Once new pulmonary nodules are identified in a patient with a history of radical nephrectomy for renal cell carcinoma, surgical excision is required for a final diagnosis before initiating therapy for metastases.
A 58-year-old woman with multiple organ metastases from breast cancer who had undergone radical mastectomy three years ago, was treated with oral 5'-DFUR 600 mg/day. Complete remission (CR) of lymph node metastasis has been maintained for twenty-two weeks, with partial response (PR) against skin, liver and pleural metastases from 94 weeks of treatment. The patient, who continues to be treated, is well and enjoying a favorable quality of life. 5'-DFUR is considered to be an effective first choice for treating a patient with advanced or recurrent breast cancer.
Fibroblasts were established in vitro from skin biopsies obtained from 55 women and 1 man with or without breast cancer and with or without exposure to radiations from the atomic bomb (A-bomb) explosion in Hiroshima. The radiosensitivity of these cells was evaluated by clonogenic assays after exposure to X-rays. Dose-response curves were fitted to a multitarget model, S/S0 = A[1-(1-e-D/D0)N]. There was no difference in the means or variances of radiosensitivity between exposed and nonexposed groups, or between groups with and without breast cancer.
Two cases of giant bullae were treated by intracavitary suction and drainage procedure under local anesthesia because of the poor pulmonary function. After staged bullectomy, the patients returned to normal life. The first case was admitted to our intensive care unit (ICU). Tube drainage was performed in the giant bulla of the left lung immediately after admission. One month after recovery from right heart failure and mediastinal shift to the right side, bullectomy was performed using linear stapler. The patient was discharged 20 days later. The second case was admitted with severe dyspnea and bilateral giant bullae were noticed. We performed tube drainage for larger bulla of the left lung under local anesthesia. Two months later, bullectomy was performed on the right side, because the bulla on the left side became smaller and the general condition of the patient improved. The patient was discharged three months later on foot and has since been asymptomatic. Giant bulla is a well-established clinical entity which includes abnormal dilatation of various parts of the tracheo-bronchial tree and other discrete sacs originating from the interstitial portion of the lung. Giant bullae are frequently associated with marked dyspnea and emphysematous symptoms. However, these symptoms depend upon various factors: size, location, valvular mechanism, condition of the contiguous lung parenchyma and the changes that may take place in the intrathoracic pressure.
The effect of portal arterialization was examined in 20 heterotopic auxiliary rat livers. Portal blood was supplied from recipient iliac artery (0.58 mm in diameter) connected to the donor portal vein using the cuff technique. Portal hypertension caused by arterial blood pressure resulted in the immediate operative death by bleeding in four of the rats (20%) from the spontaneous rupture of the graft capsule. Severe graft congestion was noticed at autopsy 3-14 days after transplantation in 13 rats. Massive portal and sinusoidal congestion and focal hemorrhagic necrosis were confirmed by pathological examination. The results of our study demonstrate that the portal arterialization used in the auxiliary rat liver transplantation would not be applicable unless the optimal hemodynamic condition is warranted.
Fibroblasts were established in vitro from skin biopsies obtained from 55 women and 1 man with or without breast cancer and with or without exposure to radiation from the atomic bomb explosion in Hiroshima. The radiosensitivity of these cells was evaluated by clonogenic assays after exposure to X-rays or to fission neutrons from a 252Cf source. Data were fitted to a multitarget model, S/S0 = A [1 - (1 - ekD)N], for both X-ray and neutron dose-survival curves. A single hit model, S/S0 = AekD, fits the neutron dose-survival responses as well. There were no differences in the means or variances of radiosensitivity between exposed and nonexposed groups or between patients with or without breast cancer. Hence, although the sample is not large, it provides no support for the hypothesis that atomic bomb radiation preferentially induces breast cancer in women whose cells in vitro are sensitive to cell killing by radiation.
Soluble interleukin-2 receptor (IL-2R) level and IL-2R positive (IL-2R+) cells were studied in twenty patients with carcinomatous pleural effusions. The mean value of soluble IL-2R level in carcinomatous pleural effusions was 2930 +/- 1722 U/ml and that in sera was 965 +/- 610 U/ml. Soluble IL-2R level in carcinomatous pleural effusions was found to be significantly higher (p less than 0.001) than that in sera of patients with carcinomatous pleural effusions and that in transudates. Serum soluble IL-2R level in patients with carcinomatous pleural effusions was found, to be significantly higher (p less than 0.001) than that in normal controls (264 +/- 70 U/ml). We also studied IL-2R+ cells in pleural fluids and peripheral blood of patients with carcinomatous pleural effusions. The mean percentage of IL-2R+ cells in carcinomatous pleural fluid lymphocytes was 22.8 +/- 17.8%, as compared with 3.0 +/- 2.2% in peripheral blood lymphocytes of normal controls (p less than 0.001). No significant differences were observed among the cell types of lung cancer examined (adenocarcinoma, squamous, small cell and large cell carcinoma) and no correlation among levels of soluble IL-2R and IL-2R+ cell in either pleural fluid or blood. Our results suggest that in patients with carcinomatous pleural effusions, T cell-mediated active immune mechanisms (IL-2/IL-2R system) against cancer cells are more active in pleural fluid than in peripheral blood.