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H Koga

Publications and source records attributed to H Koga.

At least 19 recordsLinked to original sources
PubMed1995

Detection of (1-3)-beta-D-glucan in a rat model of aspergillosis.

The G test containing factor G, fractioned from the Limulus lysate, was used to detect (1-3)-beta-D-glucan in a rat model of aspergillosis. Aspergillus fumigatus strain MF-13, 1 x 10(4) conidia, were inoculated transtracheally into rats treated with cortisone acetate (100 mg/kg) and fed a low-protein (8%) diet. Increased serum (1-3)-beta-D-glucan was found on the sixth day after inoculation in concentrations of 370 +/- 178 pg/ml (mean +/- SD) in untreated controls, and 154 +/- 43 pg/ml in rats treated with 0.5 mg/kg of amphotericin B. On day 11 (1-3)-beta-D-glucan concentrations were 2,590 +/- 2,940 pg/ml and 448 +/- 442 pg/ml, respectively. The elevation in levels of (1-3)-beta-D-glucan increased in correlation with the elevation of galactomannan antigen titers; (1-3)-beta-D-glucan is thus measurable during experimental aspergillosis in rats.

Amphotericin B↗
PubMed1995

Dysembryoplastic neuroepithelial tumor: report of three cases.

BACKGROUND: Dysembryoplastic neuroepithelial tumor (DNT) is one of the mixed neuronal-glial tumors that should be differentiated from low-grade gliomas. The recognition and correct diagnosis of DNT is important because this tumor is curable by excision. METHODS: We report three cases of histologically proven DNTs with various image studies performed preoperatively and describe characteristic findings of them, as well as those of previous reports. RESULTS: In our three cases, computed tomography (CT) showed a well-defined, nonenhancing hypodense area. Magnetic resonance imaging (MRI) demonstrated a cortical mass of hypointensity on T1- and of marked hyperintensity on T2-weighted images. I-123-IMP or Tc-99m-HMPAO single-photon emission computed tomography (SPECT) images showed marked hypoperfusion of the lesion. Thallium-SPECT showed no uptake. CONCLUSIONS: I-123-IMP, Tc-99m-HMPAO, and Thallium-SPECT images, as well as CT and MRI, may be helpful in distinguishing DNT from low-grade gliomas.

Adult↗
PubMed1995

Small flat cancer of the rectum: clinicopathologic and endoscopic features.

The clinicopathologic and endoscopic features of 15 patients with small flat cancer of the rectum were investigated. Whereas 4 patients had hematochezia, the remaining 11 patients were asymptomatic, and stool positive for occult blood was the only remarkable clinical feature in 8 of them. Endoscopic features were slight elevation with central depression in 8 lesions, flat-topped elevation in 4, and shallow depression with irregular margin in 3. The surface of the tumor was often faint red in color and frequently characterized by mucosal friability. Five flat rectal cancers were missed during initial endoscopy, and they were found by repeated endoscopic examination. Three flat cancers were not identified in the distal rectum until retroflexed colonoscopic observation was performed. Although all tumors were smaller than 2 cm in diameter and 6 of them were under 1 cm, 9 lesions had deeply invaded the submucosal layer and 7 tumors showed lymphovascular permeation. Two lesions of 1 cm or greater had metastasized to perirectal lymph nodes. These results suggest that careful observation during endoscopy is necessary to detect flat rectal cancers, and a U-turn to examine the anorectal junction should be routinely done in the appropriate age group.

Adenocarcinoma↗
PubMed1995

Holmium: yttrium-aluminum-garnet laser for endoscopic lithotripsy.

OBJECTIVES: To evaluate the holmium:yttrium-aluminum-garnet (Ho:YAG) laser for endoscopic lithotripsy on patients diagnosed with urinary tract calculi. METHODS: Thirty-eight procedures utilizing transurethral ureterolithotripsy or percutaneous nephroureteral lithotripsy were evaluated: 5 renal calculi, 31 ureteral calculi (most in the upper ureter), 1 ureteropelvic junction calculus, and 1 bladder calculus. These were mainly in cases that, after being treated with extracorporeal shock-wave lithotripsy (ESWL), were contraindicated for further ESWL. Laser parameters included energy of 0.5 to 1.0 J/pulse and pulse rate of 5 to 10 Hz. RESULTS: Composition of calculi was determined in 26 procedures. The Ho:YAG laser was effective for fragmenting all types of calculi. Patient outcome evaluated at 6 weeks after treatment showed that 33 of 38 procedures (87%) were effective. Residual calculi in 4 of the 5 unsuccessful procedures were less than 5 mm in size and judged to be able to pass spontaneously. In the remaining procedure, the calculus was passed spontaneously 3 months after treatment. No severe damage to tissues or adverse effects to the body were observed due to the Ho:YAG laser. CONCLUSIONS: On the basis of these results, we determine that this wavelength is effective for lithotripsy in addition to its previously reported usefulness for soft tissue applications, and, thus, is a cost-effective and highly useful clinical device.

Adult↗
PubMed1995

Effective renaturation of reduced lysozyme by gentle removal of urea.

To increase the folding yield of concentrated reduced lysozyme, we developed a renaturation method by means of dialysis from concentrated urea with redox agents. After lysozyme was incubated in the reducing buffer (8 M urea solution) with oxidized glutathione, renaturation of reduced lysozyme was started by dialysis against the dialyzing buffer containing 8 M urea with redox agents. The urea concentration of the dialyzing bottle was gradually diluted with dialyzing buffer without urea at a flow rate of 0.1 ml/min by high pressure pump. Using this systematic dialysis, a concentration as high as 5 mg/ml of reduced lysozyme could be renaturated in 80% yield, while the folding yield was < 5% even at a concentration of 1 mg/ml using a conventional rapid dilution method [Goldberg et al. (1991) Biochemistry, 30, 2790-2797]. Therefore, it was concluded that gentle removal of urea from denatured proteins, dissolved in concentrated urea solution, by means of dialysis should be useful to renature denatured proteins effectively.

Buffers↗
PubMed1995

Intracranial germ cell tumors: detection of p53 gene mutations by single-strand conformation polymorphism analysis.

Using polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) analysis, p53 gene mutation was examined in 12 intracranial germ cell tumors (5 yolk sac carcinomas and 7 germinomas), many of which were derived from young patients in the first to the second decade. A total of 10 mutations were detected in 4 of the 12 cases and, in 3 of them, the mutations were multiple or tandem. Among the 10 mutations, 7 were missense, 1 was splicing and 2 were silent. The 7 missense mutations were located at previously proposed hot spot codons or in their vicinity or, when outside the hot spots, at a codon encoding an amino acid conserved in most vertebrates. These findings suggested that all 7 missense mutations may actually give rise to functional alteration of the p53 protein. The splicing mutation was considered to be a germ-line mutation, though its biological effect was equivocal, since the neoplastic tissue contained an additional mutation. The pattern of the mutations was predominancy of G:C-A:T transition with frequent involvement of the CpG site. These mutations were more frequently detected in yolk sac carcinomas (60%; 3/5 cases) than in germinomas (14%; 1/7 cases), suggesting that the contribution of the p53 mutation to carcinogenesis differed with the histological type of the intracranial germ cell tumor.

Adolescent↗
PubMed1995

Occurrence of acute megakaryoblastic leukemia in a patient with idiopathic growth hormone deficiency.

We describe a case of a 15 year old boy who developed acute megakaryoblastic leukemia (AMKL) while receiving treatment with human growth hormone (hGH) for idiopathic growth hormone deficiency (GHD). He was diagnosed as having idiopathic GHD and given hGH from December 1991. The examination of his peripheral blood showed mild pancytopenia 2 months before the start of the hGH therapy. Since January 1992, paleness of the skin, general fatigue and fervescence progressed gradually. In February 1992, because of the occurrence of acute leukemia, administration of hGH was discontinued. Judging from the results of surface marker analysis of the blast cells, the patient was diagnosed as having AMKL. He was treated with chemotherapy for acute non-lymphoblastic leukemia from March 1992. A complete remission was obtained after 4 weeks of treatment. The chemotherapy was completed in July 1993. He remains in complete remission 26 months after diagnosis. This case suggests the importance of hematological examination and, when there is any abnormality which is not caused by GHD, such as pancytopenia, more detailed medical examinations (for example bone marrow examination) are necessary.

Child↗
PubMed1995

[A report to 2 cases where Stenotrophomonas maltophilia with a mucoid phenotype was isolated from the sputum].

Mucoid Stenotrophomonas maltophilia was isolated from the sputum of 2 women. Case 1 which we reported recently was primary pneumonia caused by S. maltophilia. However, in Case 2, mucoid S. maltophilia represented part of the transient flora. Interestingly, colonization of mucoid Pseudomonas aeruginosa on respiratory tract occurred in both cases after mucoid S. maltophilia was isolated from their sputum.

Female↗
PubMed1995

Disseminated intravascular coagulopathy in infection compared with that in malignant neoplasia.

The organic symptoms and results of coagulation tests of disseminated intravascular coagulopathy (DIC) in 17 patients with infection were compared with those in 12 patients with malignancy. The infectious diseases were mainly sepsis and pneumonia, and the malignancy was mainly lung cancer. The mean antithrombin III (AT III) before treatment was 54% in infection and 68% in malignancy, and the AT III values improved after administration of 1500 U of AT III concentrates per day. The mean thrombin-antithrombin complex level decreased from 22 ng/ml to 9 ng/ml after the treatment in infection, but it increased in malignancy. There were no differences in DIC scores between infection and malignancy before treatment; however, the scores were significantly more improved in infection than in malignancy after treatment (p < 0.05). The fibrin/fibrinogen degradation product level, platelet count, and fibronectin level were also significantly more improved in infection than in malignancy. This better response to treatment in infection than in malignancy is probably due to eradication of the causative organisms by antibiotics in infection. These data suggest that therapy against both DIC and the underlying disease is crucial for successful treatment.

Aged↗
PubMed1995

Trends in antimicrobial resistance of Streptococcus pneumoniae in Japan.

A total of 184 isolates of Streptococcus pneumoniae were recovered from the sputa of patients over a 5-year period in the Nagasaki area and were examined. A total of 30 strains were resistant to penicillin (MIC, > or = 0.10 micrograms/ml), 13 of which belonged to serotype 19B. These strains showed decreased susceptibility to other antimicrobial agents. Vancomycin, cefpirome, and imipenem were the most active agents tested.

Anti-Bacterial Agents↗
PubMed1995

Effect of MPL 9000 extracorporeal shock wave lithotripsy on renal hemodynamics and urine flow: assessment by 99mTc-DTPA renal scintigraphy.

The effect of extracorporeal shock wave lithotripsy (ESWL) with an MPL9000 lithotriptor on renal hemodynamics and urine flow was investigated by 99mTc-DTPA renal scintigraphy. In the first-pass scintigrams obtained within 1 min after injection of 99mTc-DTPA, there was no significant change in the time to the maximum radioactivity level and the maximum radioactivity ratio at 1 day before ESWL and 1 day or 1 month after ESWL. However, analysis of 30-min scintigrams showed that urinary clearance of radioactivity was delayed in the treated kidney 1 day after ESWL, particularly in the region targeted by shock waves, despite the absence of overt urinary tract obstruction by residual stone fragments. This change was reversible and was no longer noted 1 month after ESWL. These results suggest that ESWL with the MPL9000 lithotriptor induces a focal and temporary decrease in urine flow in the treated kidney, but has little or no effect on renal hemodynamics.

Adult↗
PubMed1995

Clinical evaluation of catheter-related fungemia and bacteremia.

Forty-four patients with catheter-related infection admitted to Hokusho Central Hospital between 1985 and 1991 were studied retrospectively. The rate of catheter-related fungemia or bacteremia to all corresponding cases of fungemia and bacteremia increased from 7.7% in 1985 to 28.8% in 1991. The isolated pathogens were Candida parapsilosis (8 strains), Candida tropicalis (6 strains), methicillin-resistant Staphylococcus aureus (MRSA) (6 strains), methicillin-sensitive S. aureus (MSSA) (5 strains) and Streptococcus epidermidis (3 strains). Bacteremia occurred after catheterization of the femoral vein for a mean duration of 37 days. The period was significantly shorter than that after catheterization of the subclavian vein (56 days). The major isolates from the subclavian vein were Candida spp. (14/17, 82.4%), followed by MRSA (1/17, 5.9%) and MSSA (1/17, 5.9%), while isolates from the femoral vein were Candida spp. (6/16, 37.5%), MRSA (5/16, 31.3%) and MSSA (3/16, 20.8%). Catheter removal alone did not improve the clinical condition, particularly in MRSA bacteremia; the combination of antimicrobial therapy and removal of the catheter was necessary for a better prognosis.

Aged↗
PubMed1995

Infections in patients with liver cirrhosis and hepatocellular carcinoma.

Infections in immunocompromised hosts have been an important clinical problem. Patients with liver cirrhosis and/or hepatocellular carcinoma are at a high risk of infection due to multiple factors. Five hundred and two patients admitted with liver cirrhosis and/or hepatocellular carcinoma were evaluated for infection. The infection rate was not influenced by the etiology of hepatic diseases or the presence of hepatocellular carcinoma, however, it increased with the advance of clinical stages of liver cirrhosis and hepatoma. The respiratory tract and urinary tract were the most common sites of infection, being involved in 50% and 28% of cases, respectively. The major pathogens of respiratory tract infection were S. aureus, H. influenzae, and P. aeruginosa. Gram-negative bacteria was the common isolate from sputum and urine, and S. aureus was also common in gram-positive bacteria. The infection rate was high in patients who died although infections could rarely be implicated as the direct cause of death. These findings should be a guide for the clinicians in treating patients with liver cirrhosis and/or hepatocellular carcinoma who exhibit signs of infection.

Carcinoma, Hepatocellular↗
PubMed1995

[Histopathological analysis of herniated cerebellar tonsils resected from the patients with Chiari type I malformation with syringomyelia].

Cerebellar tonsillectomy is a controversial treatment for Chiari type I malformation combined with syringomyelia. To demonstrate the validity of this procedure, we evaluated the postoperative clinical course, the histopathological finding in the resected cerebellar tonsils and the MR images of four patients. The patients were all women, ranging in age from 27 to 58 years old (mean: 43 years). The postoperative follows-up period lasted from 28 to 51 months (average: 38 mos), and the neurological symptoms and signs improved in all patients. Histopathological examination of the resected tonsils revealed a loss of Purkinje cells and granule cells. Vacuolated degeneration and chromatolysis were also seen, and modified Bielschowsky stain revealed axonal degeneration. These findings appeared to be irreversible. Postoperative T1-weighted MR images of the cervical and thoracic spine demonstrated a decrease in the size of the syrinx and the disappearance of evidence of tonsillar herniation in all patients. Postoperative phase-contrast MR images showed good CSF pulsation in the subarachnoid space at the craniocervical junction in all three patients examined. It was possible to avoid surgical complications by using careful microsurgical techniques. Based on these results, we concluded that cerebellar tonsillectomy is an adequate surgical strategies for treating Chiari type I malformation associated with syringomyelia.

Adult↗
PubMed1995

[Post-TUR-P stress urinary incontinence successfully treated by periurethral injection of autologous fat to the prostate: a case report].

A 77-year-old man had been suffering from stress urinary incontinence for 2 years since he had received transurethral resection of prostate (TUR-P) for benign prostatic hypertrophy. A 60-min pad test yielded 3 g of urine. Prostatic urethra was widely open and the external sphincteric injury was suggested because of the short membraneous urethra on the urethrogram. Urethral pressure profile indicated his maximal urethral closing pressure (MUCP) of 24 cmH2O and functional urethral length of 1.6 cm and cystometry demonstrated an underactive bladder, indicating that his incontinence was caused by sphincteric injury. Autologous fat injection therapy was performed in the lithotomy position under spinal anesthesia. Fifteen ml of subcutaneous fat was obtained from his lower abdomen by liposuction through a 15G needle, and 10 ml was injected submucosally from the perineum at 6 o'clock area of the prostatic apex under the guidance of transrectal echography using a 15G needle. The patient became completely dry after the procedure. MUCP and FUL increased to 35 cmH2O and 1.9 cm, respectively, although longer follow up is necessary. The advantage of autologous fat injection to the prostate for post-TUR-P SUI patients is briefly discussed.

Adipose Tissue↗
PubMed1995

[A rapid susceptibility test of Mycobacterium tuberculosis using hybridization protection assay].

The conventional drug susceptibility tests of Mycobacterium tuberculosis are time-consuming and usually require 2 to 4 weeks to obtain final results. In this study, we attempted to develop a novel method for rapid detection of drug-resistant M. tuberculosis using hybridization protection assay (HPA). Clinically isolated strains of M. tuberculosis including seven isoniazid (INH) susceptible strains and six resistant strains were used. The organisms grown on Ogawa egg medium were inoculated into Middlebrook 7H9 broth and cultured at 37 degrees C for one week. Then, the inoculum of each strain was prepared as a tenfold dilution of bacterial suspension at McFarland No. 0.5. The inocula were mixed with INH solutions to yield final concentrations of 0.1 and 1.0 micrograms/ml, and the resulting bacterial suspensions with or without test drug were cultured on the swaying plate at 37 degrees C for up to 5 days. At intervals, 50 microliters of each sample was withdrawn and subjected to the protocol of the HPA using acridinium-ester (AE) labeled DNA probe, and then the relative light unit (RLU) was read in a luminometer. In the case of the susceptible strains, a significant difference in the mode of increase in RLU ratio (% of RLU on day x/RLU on day 0) was observed between the INH-treated and drug-free control sets within three days of cultivation, while no such differences were seen in the case of the resistant strains.(ABSTRACT TRUNCATED AT 250 WORDS)

Acridines↗