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Y Orita

Publications and source records attributed to Y Orita.

At least 55 records · Page 3Linked to original sources
PubMed1996

[Pathological evaluation of superselective one-shot intra-arterial infusion chemotherapy for head and neck tumors].

Since 1992, we have treated 43 patients with head and neck tumors by superselective intra-arterial infusion chemotherapy (SIIC) via femoral artery. In 8 patients among then, operation was performed thereafter with/without radiation therapy (RT). CDDP and/or CBDCA were utilized as the chemotherapeutic modality. Only SIIC or RT showed Grade (Gr.) 0-2b pathological effects on Oboshi-Shimosato classification scheme, while a combination of SIIC and RT exhibited Gr. 2b-4 pathological effects. We conclude that a combination of SIIC and RT was most effective and had induced degeneration or necrotic changes in the tumor tissue.

Adult↗
PubMed1996

[Diuretics].

Diuretics have been empirically developed. Inorganic mercury was used as diuretics from 16C. Guy's Hospital Pills (containing the equal part of Hg2Cl2, digitalis, and squill) was well known in the 19 C. Discovery of the diuresis of merbaphen has led to develop many organomercurial diuretics and to give suggestion of the drug design of ethacrynic acid. Diuresis in patients given sulfonamide was discovered in 1938. Inhibition of carbonic anhydrase by sulfonamide was related to its diuresis. Drug design aimed to enhance the inhibition of this enzyme has obtained acetazolamide, then chlorothazide. But, the discovery of remarkably enhanced diuretic activity (decreased inhibition on the enzyme) of hydrochlorothazide changed this drug design to rondom chemical modification of thiazide ring. Then, furosemide and other loop diuretics were obtained. The structure-activity relationship of thiazides using the electronic state and other physico-chemical indices was studied by us. A large hydrophobic center linked to a positive formal charge was assumed to the receptor of thiazide. Binding of thiazide to erythrocyte which gives mild and long acting diuretic property was found by us. Recently, shut down of the tubuloglomerular feedback by loop diuretics was reported. Loop diuretics are metabolized to loss their activity. Therapeutic drug monitoring is necessary to obtain a desirable diuresis. By wide clinical use of thiazides and loop diuretics, patients with hyponatremia with eu-or hypervolemic increased. I have proposed aquaretics since 1976. In 1992, nonpeptide selective vasopressin V2 receptor antagonist (OPC-31260) was first synthesized in Japan. This has been found to cause hypotonic diuresis and elevation of serum Na level in men. The combined use of loop diuretics and aquaretics should be considered.

Animals↗
PubMed1996

[Report on the accuracy and the reliability of dip sticks].

Urinary examination with dip sticks is essential for clinical screening test and primary health care. Recently Japanese Society of Clinical Pathology has stressed the clinical use of dip sticks. Many dip sticks are available in Japan. However, few attempts have been done for external quality control of dip sticks. It is well known that there are considerable differences in the accuracy, sensitivity and stability of dip sticks. Makers are at variance in indicating concentration levels in accordance with the given color charts. Some urine chemistry analyzers for dip sticks have been developed. There was a few cases of simultaneous study on dip sticks from various makers. We, four technologists have attempted external quality control of eleven dip sticks for protein, glucose and occult blood with the same lot number (one was only for glucose) using the four different pooled urine samples and two artificial urine samples. Based on the results of this study, the following proposal to improve the accuracy and reliability of dip sticks was derived. 1) Users should have a plenty of knowledge on the difference of the quality of dip sticks of each makers. 2) Makers of dip sticks should clarify to users the method of examination, standard materials and errors. 3) Users should perform internal quality control using different pooled urine samples or different artificial urine samples on a daily basis before going with the routine work.

Glycosuria↗
PubMed1995

Superselective cisplatin (CDDP)-carboplatin (CBDCA) combined infusion for head and neck cancers.

A group of 26 patients with carcinoma of the head and neck region was treated by superselective intra-arterial infusion of cisplatin (CDDP)-carboplatin (CBDCA). The tumor locations included the tongue (n = 4), oral base (n = 2), nasopharynx (n = 2), oropharynx (n = 8), hypopharynx (n = 4) and larynx (n = 4). Using the coaxial technique, a microcatheter was placed in the lingual, ascending pharyngeal, facial and superior thyroidal arteries according to the location of the tumor. Under imaging studies, CDDP (50 mg/m2)-CBDCA (300 mg/m2) was infused into the vessel, via injectors at the rate of 12.5 ml/min. One to five injections were given every 4 weeks. During and following the chemotherapy the patients received radiotherapy (n = 22), surgery (n = 4) or both (n = 3). Sixty-six sessions of intra-arterial chemotherapy were given with no major complications. Drug-related systemic side effects were mild. The overall response rate was 96% (complete response (CR) 50% and partial response (PR) 46%). Superselective CDDP-CBDCA combined infusion is feasible, relatively non-toxic, and important as multimodality therapy.

Adult↗
PubMed1995

[Free rectus abdominis muscle perforating artery flaps for reconstruction of the head and neck defects].

During the past eight years, tissue defects of the head and neck region in a total of 45 patients were repaired with free rectus abdominis muscle perforating artery flaps. These flaps are subclassified into (1) reduced musculocutaneous flaps, (2) thin reduced musculocutaneous flaps, (3) paraumbilical perforator-based flaps, and (4) thin paraumbilical perforator-based flaps. The advantages of these flaps are as follows. Since the flaps involve no or only a small portion of the rectus abdominis muscle, (1) the muscle can be left intact on the abdominal wall, and (2) a thin flap can be easily created by simple defatting of the flap. These flaps overcome the major disadvantages of the conventional rectus abdominis musculocutaneous flap, i.e., bulkiness of the flap and frequent postoperative abdominal herniation. The territory of the thin flaps is within 10 cm around the perforator. These flaps are suitable for defects in the head and neck region, because simultaneous flap elevation is possible at the time of tumor resection. Paraumbilical perforator-based flaps are suitable for young females and elderly patients.

Aged↗
PubMed1995

[Assessment of formulas of predicted creatinine clearance from serum creatinine].

Much effects have offered to make formulas of predicted creatinine clearance (Ccr) from serum creatinine, sex, age, body weight and height. In this study, we examined 13 kinds of predicted formulas of Ccr that have been previously published. And instead of an actual body weight, we have attempted to use 4 kinds of ideal body weight (two of them reported in Japan, the others in United States) or a lean body weight. A total of 13 subjects were studied (2 healthy males and 11 males with chronic renal disease) to determine Ccr with urine collection for one hour and simultaneous measurement of inulin clearance (Cin). A highly statistical correlation between determined Ccr and predicted Ccr was observed. From predicted formula with one hour urine collection, standard error of estimation (SEE) was smallest. According to determined Cin, the subjects examined was divided into two groups (group A; Cin > or = 50 ml/min, group B; Cin < 50 ml/min). In most formulas, B group had higher correlation than A group, and each regression line got nearer to the identical line (Y = X) and SEE became smaller. The subjects examined were divided into two groups by body mass index (BMI). One is an obese and the other is a nonobese. In an obese group, SEE became smaller when an ideal body weight or a lean body weight were used in formulas instead of actual body weight. We could conclude that the clearance time and ideal or lean body weight of the patients are most important factors to assess predicted Ccr.

Adult↗
PubMed1995

Aquaretic effect of a potent, orally active, nonpeptide V2 antagonist in men.

Solute-free water diuretics (aquaretics) that antagonize hydrosmotic vasopressin 2 (V2) receptors may be useful in treating diseases in which water is retained. An orally active, nonpeptide, selective V2 antagonist (OPC-31260) was administered in six dose steps (3, 15, 30, 60, 100 and 200 mg) to six healthy, normally hydrated men to investigate the aquaretic effects in comparison with 12 placebo-treated control subjects (two at each dose). All subjects tolerated all six doses without serious clinical side effects. OPC-31260 increased the first 6-hr hypotonic urine volume dose-dependently. Administration at 30 mg raised the 6-hr urine volume to 2 times, 100 mg to 3 times and 200 mg to 4 times (1828.0 +/- 130.2 ml/6 hr) that of the placebo group (470.4 +/- 52.1 ml/6 hr). The drug increased urine flow maximally between 1 and 1.5 hr at all doses (e.g., 10.0 +/- 0.7-10.8 +/- 0.4 ml/min at 60-200 mg). The drug rapidly lowered urine osmolality for 4 hr, particularly between 60 and 90 min (e.g., 72.3 +/- 2.3 and 62.3 +/- 5.1 mOsm/kg at 100 and 200 mg, respectively). In marked hypotonic diuresis, mean free-water clearance of the 6-hr urine increased dose-proportionally into the positive range, reaching 2.82 +/- 0.21 ml/min at 200 mg.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1995

[Diuretics].

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Benzothiadiazines↗
PubMed1994

Column-switching liquid chromatographic method for the simultaneous determination of iothalamic acid and creatinine in biological fluids.

A column-switching liquid chromatographic method for simultaneous determination of iothalamate and creatinine in human serum and urine was developed. Iothalamate and creatinine were separated on a weakly acidic ion-exchange column (C1) by ion-exclusion chromatography and iothalamate excluded from the column was purified by gel chromatography on a hydrophilic gel column (C2) and then by ion-exchange chromatography on a weakly basic ion-exchange column (C3). Creatinine that was eluted from C1 after iothalamate was transferred to a hydrophilic gel column (C4) and then to a strongly acidic ion-exchange column (C5). The mobile phase for C1-C4 was a pH 3.8 propionate buffer (propionic acid-NaOH = 0.35 + 0.035 mol/kg in water) and a pH 5.6 propionate buffer (propionic acid-NaOH = 0.04 + 0.035 mol/kg in water) was used for C5. Diluted serum and urine samples could be injected directly on to C1, as the matrix of C1 is hydrophilic and C1 is backflushed after the transfer of the creatinine fraction from C1 to C4. Iothalamate and creatinine in the eluates were determined by measuring their ultraviolet absorption at 245 and 234 nm, respectively. The precision (R.S.D.) of the chromatographic method was 1.6% (n = 7) and 0.36% (n = 6) for diluted serum and urine with iothalamate concentrations of 1.0 and 10.0 mumol/l, respectively, and 0.85% (n = 7) and 0.55% (n = 7) for diluted serum and urine with creatinine concentrations of 5.77 and 272 mumol/l, respectively.

Chromatography, Gel↗
PubMed1994

Extended anterior thigh flaps for repair of massive cervical defects involving pharyngoesophagus and skin: an introduction to the "mosaic" flap principle.

"Mosaic" flaps, i.e., connected anteromedial thigh-groin flaps, and connected anterolateral thigh-medial thigh flaps, the pedicles of which are the perforators of the lateral circumflex femoral system, the superficial circumflex iliac vessels, and the perforators from the femoral vessels are used to repair cervical skin defects involving the pharyngoesophagus. Although they appear to be similar to "siamese" flaps, these mosaic flaps are a new concept because they consist of two adjacent flaps that are simultaneously elevated with double pedicles including the lateral circumflex femoral system. The pedicles of the groin or the medial thigh flaps are anastomosed to the muscle branch or the descending branch of the lateral circumflex femoral system, which is the pedicle of the anterior thigh flaps, and the system is joined to a single recipient vessel as a "bridge" flap. The main advantages of these mosaic flaps are (1) they offer single recipient vessels, (2) they offer a larger extension of the vascular territory of a skin flap, and (3) they offer the possibility of creating custom-made composite flaps such as musculocutaneous and osteocutaneous flaps, and (4) the elevation of the flaps simultaneous with head and neck tumor resection is possible. Based on cited cases, it is suggested that mosaic flaps are suitable to use for reconstruction of massive cervical defects involving the cervical skin and the pharyngoesophagus due to recurrent laryngeal carcinomas.

Aged↗
PubMed1994

Organic osmolytes in rat renal inner medulla are modulated by vasopressin V1 and/or V2 antagonists.

For the purpose of clarifying the role of vasopressin V1 and V2 receptors in osmolyte accumulation, we determined the effects on the inner medullary osmolyte content of the administration of orally active vasopressin V1 and/or V2 receptor antagonists OPC-21268 (i.e., 1-(1-[4-(3-acetylaminopropoxy)benzoyl]-4-piperidyl)- 3,4-dihydro-2(1H)-quinolinone) and OPC-31260 (i.e., 5-dimethylamino-1-[4-(2-methylbenzoylamino)benzoyl]-2,3,4,5-tet rah ydro-1H- benzazepine] under a condition of maximal urine concentration achieved by water deprivation for 4 days. Taurine content increased significantly with the use of the V2 antagonist, irrespective of the use of the V1 antagonist. Inner medullary betaine content decreased with the administration of the V1 antagonist, irrespective of the administration of V2 antagonist. The administration of either the V1 or V2 antagonist alone did not affect sorbitol content, aldose reductase activity, or aldose reductase mRNA abundance in renal inner medulla. However, the combined administration of the V1 and V2 antagonists decreased all of these significantly. Myo-inositol content was not affected by the administration of the V1 or V2 antagonists. Glycerophosphorylcholine content was decreased with the use of the V2 antagonist, irrespective of the use of the V1 antagonist, and this effect paralleled urine osmolality. In conclusion, the individual organic osmolytes responded differently to the antagonists of vasopressin V1 and/or V2 receptors. The mechanisms linked to vasopressin V1 and/or V2 receptors appeared to modulate the accumulation of some organic osmolytes in the inner medulla. Aldose reductase mRNA abundance and sorbitol accumulation in the inner medulla appeared to be mediated through either V1 or V2 receptors.(ABSTRACT TRUNCATED AT 250 WORDS)

Aldehyde Reductase↗
PubMed1994

[The effects of a day service center on the physical and mental condition and lifestyle of the disabled elderly living at home].

This study investigated the effects of a day service center on the physical and mental condition of the disabled elderly living at home, and clarified the factors which related to physical and mental effects after using the day service center. Sixty-nine male and 141 female subjects (mean age: 79.5 years) were studied by questionnaire. Among males, the characteristics of "having a spouse" and "dementia" occurred with significantly greater frequency than among female subjects, while the prevalence of "more advanced age" and "three-generation household" were significantly higher among females than males. The enjoyments at the center for the elderly were baths and/or meals, and meeting and talking with staff members, volunteers and other elders using the day service center. The survey found that the day service center helped to improve the physical and mental conditions such as cleanliness and cheerfulness. The main factors related to physical and mental effects after using the day service center were age distribution, household composition, degree of dementia and manner of bathing at the center. From the results obtained, it was concluded that the day service center provides the opportunity to improve actual living conditions and promote the welfare of the disabled elderly living at home.

Aged↗
PubMed1994

[SBOs of urinalysis, analyses of feces, CSF and body fluids].

Specific behavioral objectives (SBOs) of urinalysis, analysis of feces, cerebrospinal fluid (CSF) and body fluids should be decided carefully owing to the unique nature of these tests such as easy deterioration of specimens, false-positive/false-negative by interfering substances and the heavy reliance on conventional methods for many tests. Especially routine urinalysis, including reagent strip method and urinary sediments must be emphasized because these tests are performed by the physicians themselves at their office. Acquirement of sample collection, preservation and quality assurance for these tests are also indispensable.

Body Fluids↗
PubMed1993

Urine, serum and hair monitoring of hydrofluoric acid workers.

To define the relationship between fluoride (F) concentration in the serum, urine and hair of workers and the concentration of hydrofluoric acid (HF) in the work environment, pre- and postshift serum and urine samples of 142 HF exposed workers and 237 unexposed workers were examined. Hair specimens were also collected for the determination of F. To determine whether external contamination influences hair analysis, the control hair samples were kept in the work environment for one week. The pre-exposure levels in serum and urinary F in HF workers were higher (P < 0.01) than the control values. This suggests that F excretion from the body continues for at least 12 hours. The postshift serum and urinary F concentrations of these workers were significantly higher (P < 0.01) than the preshift concentrations. The levels of F in the hair of HF workers were also higher than in the control subjects. The concentrations of F in postshift serum and urine, and hair were in good correlation to each other. There was a linear relationship between mean serum and urinary F concentrations and HF concentration in the workplace. A mean F concentration of 82.3 micrograms/l in serum and 4 mg/l in urine with a lower fiducial limit (95%, P = 0.05) of 57.9 micrograms/l in serum and 2 mg in urine were estimated to correspond to an atmospheric HF concentration of 3 ppm, which is the maximum allowable concentration recommended by Japan Association of Industrial Health and also the threshold limit value suggested by American Conference of Governmental Industrial Hygienists.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Free combined composite flaps using the lateral circumflex femoral system for repair of massive defects of the head and neck regions: an introduction to the chimeric flap principle.

Chimeric composite flaps combined using microanastomoses consist of two or more flaps or tissues, each with an isolated pedicle and a single vascular source. Free combined chimeric flaps using the lateral circumflex femoral system were used to treat massive composite defects of the head and neck in 10 cases. A combined anterolateral thigh flap and vascularized iliac bone graft based on the lateral circumflex femoral system and the deep circumflex iliac system was the most commonly used combination. An anteromedial thigh flap and a paraumbilical perforator-based flap were also combined with this principal combination. The advantages of this chimeric flap over other osteocutaneous flaps are: (1) The flap is relatively thin and the pedicle vessels are up to 10 cm longer and are wider than those of other flaps for easier harvesting of the flap. (2) It is unnecessary to reposition the patient. (3) The vascular pedicle to the skin can be separated from that of the bone. (4) The donor site is not close to the recipient site. (5) The donor scar is in an unexposed area. (6) The skin territory of this flap is extremely wide. (7) A combined anterolateral and anteromedial thigh flap and vascularized iliac bone graft can be easily obtained as an extended combined osteocutaneous flap. (8) Other neighboring skin flaps, such as a groin flap, a paraumbilical perforator-based flap, or a medial thigh flap, can be combined with this chimeric flap because several major muscle branches to be anastomosed derive from the lateral circumflex femoral system. Chimeric composite flaps using the lateral circumflex femoral system are considered suitable for the repair of massive composite defects of the head and neck.

Adult↗
PubMed1993

Potent aquaretic agent. A novel nonpeptide selective vasopressin 2 antagonist (OPC-31260) in men.

Solute-free water diuretics (aquaretics) by antagonizing hydrosmotic vasopressin receptors (V2) may be useful in treating water-retaining diseases. The effects of intravenous administration of a newly developed nonpeptide, selective V2 antagonist, OPC-31260, at doses ranging from 0.017 to 1.0 mg/kg to groups of healthy, normally hydrated men were compared with those of 0.33 mg/kg furosemide and placebo. OPC-31260 increased the hypotonic urine volume dose dependently for the first 4 h, while furosemide induced sodium diuresis for 2 h. The absolute increase in the cumulative response in the urine to the highest doses of OPC-31260 was not significantly different from that to furosemide. The higher doses of OPC-31260 rapidly lowered urine osmolality for 2 h, particularly between minutes 15 and 45 (e.g., 1.0-mg/kg dose: 63 +/- 2 mOsm/kg in urine collected between minutes 30 and 45). In a marked hypotonic diuresis, mean free water clearance of the 4-h urine increased dose proportionally into the positive range, reaching 1.80 +/- 0.21 ml/min at 1.0 mg/kg. Whereas furosemide induced marked Na and K diuresis, OPC-31260 increased urinary Na excretion only slightly. At 4 h, 0.75 and 1.0 mg/kg of OPC-31260 almost doubled the plasma arginine vasopressin; and the higher doses increased plasma osmolality and plasma Na slightly, but did not alter plasma K, blood pressure, or heart rate. OPC-31260 thus safely induced a potent aquaretic effect in men.

Adult↗
PubMed1993

[Studies on otolaryngeal Chlamydia trachomatis infection province (a case report and seroepidemiological study)].

Recently, chlamydial infection patterns have undergone considerable change. Chlamydia trachomatis has, in particular, been described as a major cause of sexually transmitted diseases. Because of the more liberal attitude concerning sexual life-styles and behavior patterns, the oral cavity and pharynx has been increasingly becoming a site of infection for many sexually transmitted diseases. In the otolaryngeal region, because of oro-genital sexual relations, C. trachomatis infection is presently attracting a great deal of attention. The authors report a case of pharyngitis and cervical lymphadenitis due to C. trachomatis infection contracted from oral sexual activity. Initially, this was suspected to be a case of malignant lymphoma, but histological studies in biopsy specimens of the epipharynx and cervical lymph nodes revealed no malignant cells. Serum antibody titers against mycoplasma and a number of viruses were not elevated while those against C. trachomatis were, based on results of the microplate immunofluorescence antibody technique. C. trachomatis antigen was demonstrated in pharyngeal scrapings by an isolation method and direct immunofluorescence test. In addition, inclusion bodies of C. trachomatis were demonstrated in biopsy specimens from the lateral funiculus of the pharynx by direct immunofluorescence test using a MicroTrak. The authors studied the seroepidemiology of chlamydial infection in healthy controls, patients with acute respiratory infection and patients with inflammation or infection in the otolaryngeal region. Among adult patients with otolaryngeal inflammation, the carrier rate for C. trachomatis specific antibodies was higher than in other groups. In females, especially, the carrier rate for C. trachomatis specific antibodies was very high.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗