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Biomedical subjects

T Hara

Publications and source records attributed to T Hara.

At least 829 records · Page 46Linked to original sources

In vitro antimicrobial activity of a novel aminothiazolylglycylcephalosporin, MT0703S, compared with that of ceftazidime, cefoperazone and aztreonam.

The antibacterial activity of a novel aminothiazolylglycylcephalosporin, MT0703S, possessing a dihydroxypyridone moiety was compared in vitro with the activity of ceftazidime, cefoperazone, aztreonam and other beta-lactam antibiotics using seven bacterial species of a clinical origin. MT0703S showed the most potent activity against P. aeruginosa, including the ceftazidime-resistant strains, E. coli, K. pneumoniae and C. freundii. MT0703S was comparable to aztreonam but more active than ceftazidime and cefoperazone in its activity against K. oxytoca and E. cloacae, and comparable to ceftazidime against S. aureus and S. marcescens. MT0703S was more active than cefoperazone against S. marcescens but less active against S. aureus. The stability of MT0703S against various beta-lactamases appeared to be intermediate between the stability of ceftazidime and that of cefoperazone. The antimicrobial activity of MT0703S increased in a low-iron environment and decreased in a high ferric ion concentration.

Aztreonam↗

[An experience of anesthesia in a case of WPW syndrome].

WPW (Wolff-Parkinson-White) syndrome is a rare disease characterized by electro-cardiographic anomalies associated with a history of recurrent supraventricular tachycardia. ECG abnormalities consist of a short PR interval and a broad QSR complex with a slurred upstroke. We experienced general anesthesia in a 29-year-old male with this syndrome for operation of maxillary cyst. Physical laboratory examinations of this patient revealed his conditions of within normal limits with the exception of ECG findings. After premedication with atropine, hydroxyzine and pethilorfan intramuscularly one hour prior to anesthesia, anesthesia was induced with intravenous thiopental 325 mg and the trachea was intubated with intravenous succinylcholine 40 mg. Thereafter anesthesia was maintained with 2.0% enflurane and 67% nitroxide in oxygen under controlled ventilation. During 1 hour operation, vital signs remained stable and paroxysmal tachycardia was not recognized on the ECG. The postoperative course was uneventful.

Adult↗

[A case of general anesthesia with Pierre Robin syndrome and scoliosis].

We experienced a case of general anesthesia in a one-year-old boy for palate plasty with a slight micrognathia, cleft palate and scoliosis. At the first anesthesia, we tried two times oral intubation under the spontaneous respiration after slow induction with halothane, nitrous-oxide in oxygen, twice but were unsuccessful. In site of easy intubation with succinyl choline chloride rales and bronchial secretions increased and the operation was postponed. Ten months later, the same operation was planned and re-tried using same method as the first anesthesia. As this time, it was relatively easy to intubate, blood pressure and heart rate were stable during the operation. The recovery from anesthesia was smooth. From the experience of this case, we recognized again that preoperative respiration management was very important for these patients.

Anesthesia, Dental↗

[A case of acute pericarditis secondary to mediastinitis].

A 45-year-old man who complained of swallowing disturbance and chest pain in inspiration phase was admitted for evaluation of "pericarditis". A chest X-ray film on admission disclosed a wide mediastinal shadow and pleural effusion on the right side. Bilateral tonsils were swollen, and covered with pus. A Computed tomogram of the chest showed a shadow of exudate contained with air in the mediastinum. Mediastinal drainage, tonsillectomy and drainage of fistula from pre-tracheal space to upper mediastinum were immediately performed. Staphylococcus aureus was confirmed from the sputum and mediastinal effusion. Thus, acute mediastinitis was confirmed as an etiological diagnosis of "pericarditis" in this patient.

Acute Disease↗

A new anterior capsular opening: dumbbell opening--its efficacy in the human eye.

Using excised pig eyes and a human eye-bank eye, we demonstrated the efficacy of our new anterior capsular opening, the dumbbell opening, especially for the human eye. The opening consists of two microcircular holes made by an automated electric microtrephine, connected by a straight cut made with scissors. The 3.5-mm-long dumbbell opening fully retained its original shape after cataract removal and posterior-chamber intraocular lens insertion.

Aged↗

[Clinical application of Sonolith 3000 type on extracorporeal shock wave lithotripsy for renal and ureteral stones].

With Sonolith 3000, a new extracorporeal shock wave lithotriptor, we performed extracorporeal shock wave lithotripsy (ESWL) on 34 patients with upper urinary stones, including 5 patients with target stones of this clinical application in both sides. The 39 target stones in the 34 patients were located in the renal calyx (13 cases), renal pelvis (14 cases), renal calyx and pelvis (1 case), renal pelvis and ureter (1 case), and upper ureter (10 cases). The ultrasound-aiming system gave a satisfactory imaging of the target stones in 94.9% of cases (37/39 cases). During the ESWL treatment, 32 patients (94.2%) did not need anesthesia, but 2 patients (5.9%) needed epidural anesthesia because of intolerable pain and/or terror of pain. The average number of treatments per case was 2.08, and the average dose of shock waves per treatment was 3,691.1. The stone-free rate on the 14th, 42nd and 90th days after the last ESWL treatment were 28.2% (11/39), 51.3% (20/39) and 64.1% (25/39), respectively. Out of 39 cases, 31 cases (79.5%) were either stone-free or had only sand-like residual stones on the 90th day. Most cases had minimal side effects, such as transient macroscopic hematuria (100.0%), skin eruption (50.0%) and back pain (41.2%), but one case needed a 1,200 ml transfusion because of perirenal hematoma immediately after 1st session of ESWL treatment with 2,300 shock waves (13 kv). The serum total bilirubin level on 1st day after the last session of ESWL treatment was significantly increased when compared with the preoperative level, but the level was not significantly increased after the 1st session.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Primary carcinoma in situ of the ureter: a case report].

A case of primary carcinoma in situ of the ureter in a 77-year-old man is reported. The patient had been to another hospital with right flank pain and macroscopic hematuria. Ultrasound sonogram showed right hydronephrosis. An excretory urogram showed right hydronephrosis and stenosis of right ureter. He was referred to our hospital for further evaluation and treatment. Retrograde pyelogram demonstrated a right ureteral stricture at the level of S1-2, but no space occupying lesion was detected in the ureter. Cytology of voided urine was negative for malignant cells and no other abnormal findings were present. Probe laparotomy was performed under the preoperative diagnosis of ureteral stricture. During the operation, frozen section examination of the stenotic ureter showed carcinoma in situ and so we performed right total nephroureterectomy with a bladder cuff. Pathologic diagnosis was primary carcinoma in situ of the right ureter. The patient has been doing well for six months postoperatively with no evidence of recurrent or metastatic disease.

Aged↗

[Oocyte fertilizability and hormonal environment of human preovulatory follicles in hyperstimulated cycles in an in vitro fertilization program: Are mature preovulatory follicles undergoing atresia?].

Steroid hormones in preovulatory follicular fluid, maturity of the oocyte-corona-cumulus complex (OCCC), and oocyte fertilizability were studied in 55 hyperstimulated cycles in 40 patients who were indicated for in vitro fertilization and embryo transfer due to tubal infertility. Aspirated follicles were categorized into four groups according to the degree of oocyte maturation and fertilizability, i.e. follicle (Fol)-1 (non-fertilized, intermediate maturation), Fol-2 (fertilized, intermediate maturation), Fol-3 (fertilized, full maturation), and Fol-4 (non-fertilized, full maturation). Estradiol (E2), progesterone (P), and delta 4- androstenedione (delta 4A) concentrations were highest in Fol-3, being lower in Fol-2 and Fol-1 sequentially. Fol-3 contained significantly more E2 and P than did Fol-1, showing that the degree of oocyte maturation and fertilizability correlate with concentrations of E2 and P in the follicles. A comparison of Fol-3 and Fol-4 revealed significantly higher concentrations of delta 4A in Fol-4, whereas differences in E2 and P concentrations were not significant although Fol-4 values were lower. This comparison indicated that Fol-4 were already undergoing atresia at the time of oocyte retrieval, containing morphologically mature OCCC which had lost fertilizability. This study shows that steroid hormones in the follicular fluid reflect oocyte viability and fertilizability, and suggests that preovulatory follicles with mature oocytes can also undergo atresia.

Chorionic Gonadotropin↗

Accommodative intraocular lens with spring action. Part 1. Design and placement in an excised animal eye.

We designed an intraocular lens (IOL) with spring action, which we call the Spring IOL, with the idea of providing a slight but adequate accommodative power. The Spring IOL consists of two 6.0-mm optics, held 4.38 mm apart, and four flexible loops. The optics are made of polymethylmethacrylate (PMMA) and the loops of polyvinylidene fluoride. The lens's refractive power is provided by the anterior optic; the posterior optic acts as a footplate to restrict the anteroposterior movement of the anterior optic. By torsionally compressing the obliquely arranged loops, a 10.0-mm 3-dimensional IOL can be reduced to 6.0 mm and inserted in the capsular bag through a 3.5-mm capsular opening. Because the Spring IOL is made of the same materials as conventional IOLs, most of the problems hindering the development of a refilling material (which could also provide accommodation) are avoided. In this first report we discuss the design of the lens, the refractive theory involved, and our experience inserting it in an excised animal eye.

Accommodation, Ocular↗

[Dysphagia in olivopontocerebellar atrophy].

Clinical, radiological and manometric studies on thirteen patients with olivopontocerebellar atrophy were performed in order to investigate the characteristics of dysphagia. As a clinical study, a detailed history of dysphagia was taken to distinguish two types of dysphagia, that is to say swallowing disturbance in a narrow sense and passage disturbance. In the radiological study, each phase of swallowing was observed by X-rays with contrast medium (Dionosil). In the manometric study, intraluminal resting pressure in the esophagus and pressure of esophageal contraction after swallowing were measured. The results were as follows: Eight patients had the sensation of swallowing disturbance in a narrow sense and five patients has the feeling of passage disturbance. In X-ray studies four patients had pooling in piriformis sinus and six patients had slight dilatation of the lower esophagus. In manometric studies, six patients had low intraluminal resting pressure of the upper esophageal sphincter, but almost all patients had normal intraluminal resting pressure throughout the esophagus and in the lower esophageal sphincter. Two patients, who had suffered for five and seven years, had loss of both negative and positive wave in the upper esophageal sphincter after swallowing. Another three patients, who had suffered for two, six and seven years, respectively had loss of negative wave in the upper esophageal sphincter after swallowing. Regarding peristaltic wave, eight patients had low amplitude of the wave. Two patients, who had suffered for five and six years, had diphasic shape of the wave. One patient, who had suffered for nine years, had synchronous wave. Nine patients had loss of negative wave in the lower esophageal sphincter.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[A case of malignant neuroepithelioma in the retroperitoneum].

Reported is a case of a malignant neuroepithelioma in the retroperitoneum. The patient was a 37-year-old male suffering from lumbago and edema of the lower extremities. After ultrasonography and a CT scan, a diagnosis of a retroperitoneal tumor was made and a surgical resection of the tumor was performed in October, 1985. The subsequent pathological diagnosis was malignant neuroepithelioma which showed epithelioid cell clusters that stained positively to NSE. Eleven months later, metastatic tumors were seen present in the lungs and the liver though they regressed markedly after adjuvant chemotherapy with ADM, CPM, and VCR. Forty-one months after his first operation, the patient continues to work. In this case, adjuvant chemotherapy has proved effective.

Adult↗

Preparation of EGF labeled liposomes and their uptake by hepatocytes.

The preparation of epidermal growth factor (EGF) bearing liposomes (EGF-liposomes) and their uptake by rat hepatocytes were described. EGF was bound to the liposomal surface by the disulfide bridge linkage using a heterobifunctional cross-linking reagent, N-hydroxysuccinimidyl-3-(2-pyridyl-dithio) propionate. EGF-liposomes were taken up in a significant amount by rat hepatocytes in an EGF receptor mediated manner, and their uptake was dependent on the amount of labeled EGF coupled to the liposomal surface. These results raise the possibility that the EGF-liposomes may be an effective drug carrier to the cells having EGF-receptors like some cancer cells.

Animals↗

Preparation and in vitro cytotoxicity of a methotrexate-anti-MM46 monoclonal antibody conjugate via an oligopeptide spacer.

A method was developed by which conjugates of methotrexate (MTX) with antibody were prepared via an oligopeptide spacer which, after internalization of the conjugates into the target cells, would be cleaved by lysosomal enzymes to liberate MTX or its derivative(s) for entry of the drug into the cytoplasm through the lysosomal membrane. The conjugate of MTX with a monoclonal antibody (MAb) (aMM46) to mouse mammary carcinoma MM46 cells prepared by this method via Leu-Ala-Leu-Ala showed potent, antibody-directed cytotoxicity through lysosomal degradation of the conjugate, most likely at the tetrapeptide spacer. This was supported by the following observations: (a) the cytotoxicity of the aMM46 conjugate was more potent than that of the corresponding normal gamma-globulin conjugate, the antibody alone not being cytotoxic; (b) the conjugate retained its potent cytotoxicity to MM46 cells even after removal, by hydroxylamine treatment, of a less stably bound MTX derivative which might have been released extracellularly and have caused non-specific cytotoxicity by entering the cells via the membrane active transport system for MTX; (c) the cytotoxicity was not inhibited by thiamine pyrophosphate, an inhibitor of the MTX transport system; (d) the cytotoxicity was inhibited significantly with ammonium chloride, which inactivates lysosomal enzymes by raising the pH; and (e) the cleavability of the Leu-Ala-Leu-Ala spacer by the lysosomal enzymes was verified by using bio-undegradable poly(D-lysine) and biodegradable poly(L-lysine) as the lysosomotropic macromolecular carriers: unlike the poly(L-lysine) counterpart, the direct MTX-poly(D-lysine) conjugate showed very weak cytotoxicity while the tetrapeptide-mediated conjugate of MTX with poly(D-lysine) exhibited potent cytotoxicity.

Animals↗

Effects of dilazep (Comelian) on the central purinergic system: inhibitory effects on clonidine-induced aggressive behavior.

Mice given clonidine (20-50 mg/kg i.p. and 5 micrograms i.c.v.) exhibited aggressive behavior. Dilazep as well as N6-(L-phenylisopropyl) adenosine (adenosine agonist) inhibited this behavior. Dilazep combined with N6-(L-phenylisopropyl) adenosine markedly inhibited the behavior at low doses that were without effect when given alone whereas the inhibitory effect of dilazep on the behavior was reversed by caffeine and 8-phenyltheophylline, which are adenosine antagonists. The results suggest that the inhibitory action of dilazep on clonidine-induced aggressive behavior can be substantially attributed to central purinoceptor stimulation.

Aggression↗

Ultrasound spatula.

A spatulalike tip is made from a 0.9-mm ultrasound (Fragmatome) tip. It is attached to a Fragmatome handpiece and used with ultrasound vibration at an intensity of about 6 W/cm2. (An infusion needle [May Needle] is used as a separate irrigating instrument.) Because the apex of the tip is rounded and lacks a simultaneous aspirating function, there is almost no danger of damaging the capsule if used carefully. This instrument is useful for dissecting the cataract to remove it through a smaller capsular incision, and in removing lens epithelial cell by applying it from the outer surface of the anterior capsule without damaging the capsule.

Cataract Extraction↗

EBV gene expression in an NPC-related tumour.

A nasopharyngeal carcinoma tumour (designated C15) propagated in nude mice has been used to generate a large cDNA library that we have analysed for Epstein-Barr virus (EBV) gene expression. No gross alterations exist in viral DNA from C15 relative to other human isolates and the large deletion present in the B95-8 'prototype' viral strain established in marmoset cells is not found; C15 contains no linear virion DNA. In the cDNA library, of the six EBV nuclear antigens (EBNAs) expressed in latently infected B-lymphocytes, only clones for EBNA-1 are found. These data are confirmed by immunoblotting. Sequence analysis shows the EBNA-1 mRNA splicing pattern in the carcinoma to differ from that observed in B-lymphocytes. Further, contrary to observations with B-cell lines, most viral transcription in the tumour is localized onto the 'rightmost' region of the conventional EBV physical map. Transcripts identified corresponding to known genes include those for the latent membrane protein (LMP), the alkaline DNA exonuclease and probably the terminal protein; major transcripts are also derived from the BamHI D fragment and the region deleted in B95-8 EBV DNA. Novel transcripts have also been identified that proceed in an anti-sense direction to genes encoding functions associated with replication, such as the viral DNA polymerase. They contain a large, hitherto unidentified, open reading frame in the viral genome that is complementary to the putative function known as BALF3 and a smaller open reading frame complementary to BALF5 (the DNA polymerase gene). From the present studies we can conclude that: (i) EBV transcription patterns in the epithelial cells vary markedly from those identified previously in B-cells, reflecting differential use of promoters or splicing patterns. (ii) Transcription is tightly regulated and restricted in the C15 tumour with many latent genes, notably EBNAs 2-6, being 'switched off.' (iii) A family of cytoplasmic RNAs are transcribed in an antisense direction to a number of existing open reading frames in the EBV genome. (iv) There are a number of mutations in C15 transcripts relative to the B95-8 genome, some of which could result in amino acid alterations in proteins.

Amino Acid Sequence↗

Cytotoxicities of two disulfide-bond-linked conjugates of methotrexate with monoclonal anti-MM46 antibody.

In studies on (antitumor antibody)-drug conjugates as potential antitumor agents, the amide derivatives of methotrexate (MTX) with cysteine and with 2-mercaptoethylamine (cysteamine) (MTX-Cys and MTX-MEA, respectively) were linked via a disulfide bond with a monoclonal antibody (alpha MM46) to a mouse mammary tumor MM46 with attached 3-(2-pyridyldithio) propionyl groups to give conjugates of MTX with alpha MM46 (MTX-Cys-SS-alpha MM46 and MTX-MEA-SS-alpha MM46, respectively). These two conjugates are both linked by a disulfide bond and are very similar in structure, but MTX-MEA-SS-alpha MM46 showed only weak in vitro cytotoxicity against MM46 cells, whereas MTX-Cys-SS-alpha MM46 had strong cytotoxicity. The cytotoxicity of the latter was comparable to that of the conventional direct MTX-alpha MM46 conjugate prepared with an MTX-active ester. However, this conjugate had a greater selectivity than that of the direct conjugate, calculated as the IC50 (concentration of a conjugate by MTX equivalence required for suppression of the number of viable MM46 cells to 50% of that of the untreated control) for the corresponding nonspecific conjugate divided by the IC50 for the alpha MM46 conjugate. The inhibitory activities of MTX-Cys and MTX-MEA on dihydrofolate reductase were similar. The cytotoxicity of MTX-Cys-SS-alpha MM46 was not affected by thiamine pyrophosphate, an inhibitor of the active transport of MTX across the cell membrane, but was decreased significantly by ammonium chloride, a lysosomotropic amine. However, the cytotoxicity was decreased only to a small extent by leupeptin, an inhibitor of lysosomal cysteine proteases cathepsins B, H, and L. These results suggest that the cytotoxicity is mediated by lysosomes, and may involve lysosomal enzymes other than cathepsins B, H, and L.

Animals↗