Search PubMed⌕ Search

Biomedical subjects

R Hayashi

Publications and source records attributed to R Hayashi.

At least 163 records · Page 9Linked to original sources
PubMed1995

[Changes in respiratory function before and after laryngectomy].

Many patients with head and neck cancer have a smoking history, and pulmonary complications frequently lead to post-operative death. Due to technical problems, spirometric pulmonary function tests are rarely performed in patients with laryngectomy. The purpose of this study is to evaluate respiratory function in patients with laryngectomy. We made a tracheal mask with a heat and moisture exchanging baseholder, and used it for spirometry. Eight patients with laryngectomy, including 5 with laryngeal cancer and 3 with hypopharyngeal cancer, were studied. Arterial blood gas analysis and pulmonary function measurements, such as VC, % VC, FEV1.0% and V25/height (V25/HT), were evaluated before and after laryngectomy. Statistical analysis of the data was performed with the Wilcoxon rank-sum test. The following results were obtained: 1) No statistically significant changes in arterial blood gases and FEV1.0% were found. 2) A statistically significant decrease in VC was found after total laryngectomy (p < 0.05). 3) A statistically significant decrease in V25/HT, which reflects small air way closure of the lung, was observed after total laryngectomy (p < 0.05). In all cases, the V25/HT value was below normal limits. We concluded that the decrease in VC was caused by a decrease in dead space in the upper airway, and that V25/HT may be a good parameter for evaluation of pulmonary function after laryngectomy.

Aged↗
PubMed1994

Cytogenetic abnormalities in two cases of neuroblastoma.

Neuroblastomas are common solid tumors in children. We report chromosome analysis of two neuroblastomas, each studied at diagnosis and at recurrence. The first case was a clinical stage D tumor which showed 45,X-Y, add(1)(p34),der(15)t(Y;15)(q11;p13), and double minutes on cytogenetic analysis at diagnosis. At recurrence, the same structural abnormalities were present along with a homogeneously staining region (hsr) at 8q22, 19p12, or 3p23 in each of three related clones. The hsr were shown to represent amplification of the N-myc gene by in situ hybridization. Cytogenetic analysis of the second tumor, stage D-S, showed 48-54,XX,der(1)add (1)(q41), +2, +7, +7, inv(9), +17, + mar. The lack of demonstrative involvement of 1p or visible evidence of gene amplification has also characterized the limited number of D-S specimens previously described, suggesting that stage D-S neuroblastoma indeed differs from stage D disease at the genetic level.

Abdominal Neoplasms↗
PubMed1994

The effect of the oxytocin antagonist atosiban on preterm uterine activity in the human.

OBJECTIVE: The purpose of this study was to test the hypothesis that infusion of the oxytocin antagonist atosiban results in decreased preterm uterine activity in the human. STUDY DESIGN: A randomized, double-blind, placebo-controlled trial was performed. One hundred twenty women from 20 to 36 weeks' gestation with a complaint of labor who had more than four uterine contractions per hour after intravenous hydration but no evidence of cervical changes were randomized to receive a 2-hour intravenous infusion of atosiban at a rate of 300 micrograms/min or placebo. Ond hundred-twelve subjects (56 in each arm) were suitable for analysis of efficacy. Both groups remained at bed rest and received hydration. RESULTS: The mean percent decrease in contraction frequency was greater in atosiban subjects compared with controls (55.3% +/- 36.3% vs 26.7% +/- 40.4%, mean +/- SD, p < 0.001). A minimal (< 20%) decrease or an increase in contraction frequency was noted in 25 placebo subjects (45%) and seven atosiban subjects (13%). There was no clinically or statistically significant change in maternal blood pressure or heart rate during the infusion. The only adverse experiences possibly related to the drug were nausea and vomiting in one atosiban patient. CONCLUSION: A 2-hour infusion of the oxytocin antagonist atosiban resulted in a significantly greater decline in contraction frequency compared with controls. Oxytocin appears to play a role in the maintenance of preterm uterine activity in the human.

Adult↗
PubMed1994

Enterococcus faecalis aggravates pyelonephritis caused by Pseudomonas aeruginosa in experimental ascending mixed urinary tract infection in mice.

Mixed urinary tract infection was caused by simultaneous inoculation of 10(4) CFU each of Enterococcus faecalis TN2005 and Pseudomonas aeruginosa P9 into the bladders of CBA/J mice. Both organisms proliferated in the kidneys, and viable cell counts of E. faecalis TN2005 reached a peak level of 4.1 x 10(5) CFU per pair of kidneys within the first 24 h, while P. aeruginosa P9 counts increased more slowly. The number of P. aeruginosa P9 cells peaked at 8.3 x 10(6) CFU per pair of kidneys 5 days after infection. Five days after mixed infection, infiltration of neutrophils into the renal pelvis and renal medulla was observed. Immunohistochemical staining revealed the presence of E. faecalis antigen in the renal medulla. P. aeruginosa antigen was detected mainly in the renal pelvis 5 days after infection and in the renal medulla as well as the renal pelvis 14 days after infection. Mixed infection induced pyelonephritis within 5 days after mixed infection, while it was not observed until 14 days after infection with P. aeruginosa P9 alone. P. aeruginosa P9 inoculated together with E. faecalis TN2005 was more resistant to eradication from the kidneys by beta-lactam antibiotics than P. aeruginosa P9 inoculated alone. These results suggest that E. faecalis TN2005 invades the renal medulla first in mixed urinary tract infection and induces histological changes which lead to aggravation of the pyelonephritis caused by P. aeruginosa P9.

Animals↗
PubMed1994

Optically active antifungal azoles. III. Synthesis and antifungal activity of sulfide and sulfonamide derivatives of (2R,3R)-2-(2,4-difluorophenyl)-3-mercapto-1-(1H-1,2,4-triazol-1-yl)-2-b utanol.

In an effort to find potent antifungal agents, optically active sulfur-containing triazole derivatives, sulfides (3) and sulfonamides (4), were prepared and evaluated for antifungal activity against Candida albicans in vitro and in vivo. The sulfides (3) were prepared by the reaction of (2R,3R)-2-(2,4-difluorophenyl)-3-mercapto-1-(1H-1,2,4-triazol-1-yl )-2-butanol (1) with various heteroarylmethyl chlorides in the presence of sodium methoxide. The sulfonamides (4) were synthesized starting from the disulfide (15) in three steps including oxidation of the corresponding sulfenamides (17). Some of the sulfur-containing triazole derivatives (3, 4) showed strong protective effects against candidosis in mice.

Antifungal Agents↗
PubMed1994

[Comparative study on placental transfer and maternal distribution of organic and inorganic tin following oral administration in pregnant rats].

Placental transfer and body distribution of triphenyl tin chloride (TPTC) and tin chloride (SnCl2) were investigated in pregnant rats. Pregnant wistar rats were orally administered TPTC at 0, 1.0 and 2.0 mg/rat/day during 6-10 and 14-18 days of gestation, and with SnCl2 at 0 and 20 mg/rat/day on 7, 10 and 15 days of gestation (group treated 3 times) or 6-10 and 13-16 days of gestation at 0 and 20 mg/rat/day (group treated 9 times). On day 20 of gestation in rats treated with TPTC, and day 17 in rats with SnCl2, fetuses, placentas, maternal blood and organs were obtained for analyses. Mean fetal tin levels from rats treated with 1.0 and 2.0 mg TPTC were 0.05 and 0.11 microgram/g wet weight, respectively, these values being significantly (P < 0.01) higher than in the control group. The latter was higher than the former at a significance level of 5%. No significant difference between fetal tin levels from rats treated with SnCl2 and the control group could be detected. Following oral TPTC administration, tin was present in maternal liver, kidney and brain in high concentrations. Following the oral administration of SnCl2, the tin level was highest in bone and kidney, but none could be detected in the brain.

Administration, Oral↗
PubMed1994

Working conditions in home care: a survey of Washington state's home care workers.

Home care services make it possible for millions of older Americans to continue living in the community. Such services may enhance the recipients' quality of life while providing essential respite to family caregivers. But while there has been increasing recognition of the burden borne by the predominantly female family caregivers, there has been less attention to the plight of the home care workforce. With the growth of the home care industry, the burden of care has to some extent shifted from one category of female caregivers to another. This paper, based on a survey of 16 agencies and 1,900 workers, examines the employment conditions of home care workers in Washington state. The study reveals a pattern of harsh working conditions, low wages, and few benefits. The findings raise questions about the ethics and efficacy of government policies that are based on the exploitation of home care workers.

Adult↗
PubMed1994

Efficacy of steroid therapy on liver metastasis of thymic carcinoid.

We present a 61-year-old man who was hospitalized because of dyspnea, abdominal pain and liver dysfunction accompanied by ascites due to hepatic metastasis of a thymic carcinoid 20 years after the primary tumor was excised. His symptoms and liver function were well controlled by prednisolone, 30 to 60 mg daily, for the next 2 years, with a reduction in the size of the hepatic tumors and in the accumulation of ascites. He subsequently contracted pneumonia due to methicillin-resistant staphylococci, developed disseminated intravascular coagulation (DIC) and died. Thus, prednisolone should be considered for treating patients with metastasis of a thymic carcinoid.

Carcinoid Tumor↗
PubMed1994

Primitive neuroectodermal tumor arising in the pancreas.

Peripheral primitive neuroectodermal tumors (PNETs) are extra cranial primitive small round blue cell tumors showing histologic, immunohistochemical or electron microscopic evidence of neuroectodermal differentiation. They are most commonly encountered in the soft tissue or bone in children and young adults. We report an unusual case of a PNET arising in the pancreas. A 17-yr-old male presented with a pancreatic mass and underwent a pancreatoduodenectomy. Histologically, the neoplasm was composed of sheets of small round cells that stained for cytokeratin, neuron specific enolase, and 12E7 but not muscle specific action, desmin, common leukocyte antigen, chromogranin, synaptophysin, or other islet cell markers. The diagnosis of PNET in this unusual location was confirmed by cytogenetic analysis which showed the chromosomal translocation characteristics of PNETs, t(11;12)(q24;q12). This case highlights the difficulty in the diagnosis of PNET when it is present in visceral organs where other neuroendocrine neoplasms and adenocarcinomas are more common.

Adolescent↗
PubMed1993

Stereoselective determination of the active metabolites of a new anti-inflammatory agent (CS-670) in human and rat plasma using antibody-mediated extraction and high-performance liquid chromatography.

The main metabolites of (+-)-2-[4-(2-oxocyclohexylidenemethyl)phenyl]propionic acid (CS-670), a new pro-drug anti-inflammatory agent of the 2-arylpropionic acid type, have one or two chiral centres arising from reduction of the oxocyclohexylidene moiety in addition to an original chiral centre in the propionic acid moiety. To determine these metabolites stereoselectively, antibody-mediated extraction was investigated as a stereoselective clean-up method prior to chiral HPLC. Immunoglobulin G, which recognizes each stereoisomeric cyclohexanol moiety, was coupled to cyanogen bromide-activated Sepharose 4B to prepare re-usable immobilized antibody, and its specificity was improved by examination of a washing process after charging of samples. Plasma extracted with the immobilized antibody column was derivatized with a chiral reagent to separate the enantiomers of the propionic acid moiety by HPLC. This newly developed analytical method clarified the stereoselective biotransformation of the pro-drug to pharmacologically active forms in humans and rats related to reduction of the oxocyclohexylidene moiety and chiral inversion in the propionic acid moiety.

Animals↗
PubMed1993

The effects of walking at the anaerobic threshold level on vertebral bone loss in postmenopausal women.

The purpose of this study was to determine the optimal intensity of exercise necessary to prevent the postmenopausal bone loss on the basis of anaerobic threshold (AT). Thirty-three postmenopausal women were randomized to control (group C: n = 12) or two exercise groups (group H and group M). All women performed a treadmill exercise test, and the AT was measured by expired gas analysis. The exercise regimen consisted mainly of walking at a speed that kept the exercise heart rate above the AT (group H: n = 12) or below the AT (group M: n = 9). Exercise was performed for 30 minutes, three times a week for 7 months. The bone mineral density (BMD) of the lumbar vertebrae was measured using dual energy X-ray absorptiometry. The BMD level in group C decreased by 1.7 +/- 2.7%, but there was a significant increase of 1.1 +/- 2.9% in group H. In group M there was a decrease of 1.0 +/- 3.1% which did not differ from group C. In group C, serum osteocalcin and urinary hydroxyproline excretion were significantly increased, but no changes were seen in either of the exercise groups. Urinary calcium significantly decreased in the exercise groups. We conclude that short-term (7 months) exercise with intensity above the AT is safe and effective in preventing postmenopausal bone loss.

Absorptiometry, Photon↗
PubMed1993

Familial cryptotia.

A case of familial cryptotia is presented, and the hereditary basis for this condition is discussed. Although, intuitively, the distribution of the intrinsic auricular muscle, the primary etiologic factor in cryptotia, must be determined genetically, further studies are needed to establish the mode of inheritance.

Adolescent↗
PubMed1993

Therapeutic effect of cefozopran (SCE-2787), a new parenteral cephalosporin, against experimental infections in mice.

The therapeutic effect of cefozopran (SCE-2787), a new semisynthetic parenteral cephalosporin, against experimental infections in mice was examined. Cefozopran was more effective than cefpiramide and was as effective as ceftazidime and cefpirome against acute respiratory tract infections caused by Klebsiella pneumoniae DT-S. In the model of chronic respiratory tract infection caused by K. pneumoniae 27, cefozopran was as effective as ceftazidime. The therapeutic effect of cefozopran against urinary tract infections caused by Pseudomonas aeruginosa P9 was superior to that of cefpirome and was equal to those of ceftazidime and cefclidin. In addition, cefozopran was more effective than ceftazidime and was as effective as flomoxef in a thigh muscle infection caused by methicillin-sensitive Staphylococcus aureus 308A-1. Against thigh muscle infections caused by methicillin-resistant S. aureus N133, cefozopran was the most effective agent. The potent therapeutic effect of cefozopran in those experimental infections in mice suggests that it would be effective against respiratory tract, urinary tract, and soft tissue infections caused by a variety of gram-positive and gram-negative bacteria in humans.

Animals↗
PubMed1993

A serial computerized tomographic study of the interval form of CO poisoning.

Serial computerized tomography (CT) was performed to quantitatively characterize cerebral changes in 1 case of the interval form of carbon monoxide poisoning. The patient was comatose for 2 days, regained consciousness for 8 days, and then developed akinetic mutism. During the remission period, a low-density area in the cerebral white matter was observed to enlarge progressively. These results suggest that the demyelination of the cerebral white matter progressed throughout the interval period. A correlation between changes in CT abnormalities and clinical presentation is described.

Aged↗
PubMed1993

Cardiac myxoma metastasized to the brain: potential role of endogenous interleukin-6.

Metastasis of a cardiac myxoma to the brain is extremely rare. We present the case of a 70-year-old man who had an atrial myxoma and two metastatic myxomas in the brain. The intracranial lesions were in fact diagnosed before the cardiac myxoma, since the patient developed hemiparesis before his cardiac symptoms occurred. Computerized tomography of the brain showed two high-density lesions, the larger of which was removed surgically. Follow-up computerized tomography revealed a progressive enlargement of the second lesion which was then resected. Histopathological examination showed all lesions to the benign myxomas. Interestingly, high concentrations of interleukin-6 were present in the patient's serum and cardiac myxoma. Interleukin-6 may possibly potentiate metastasis of cardiac myxoma.

Aged↗