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Kazuo Suzuki

Publications and source records attributed to Kazuo Suzuki.

At least 91 records · Page 5Linked to original sources
PubMed2002

The value of power Doppler imaging to predict the histologic components of benign prostatic hyperplasia.

BACKGROUND: The response of symptoms caused by benign prostate hypertrophy (BPH) to alpha blockade is related to the area density of the smooth muscle of the prostate. If this density could be determined by ultrasound examination, ultrasound might be useful in predicting the efficacy of alpha-blocker therapy. In this study, various ultrasonographic parameters obtained by transrectal method (TRUS) were compared with histologically measured components. METHODS: Before surgery, ultrasonic power Doppler imaging (PDI) of the prostate was performed using a transrectal probe. The volume of total prostate, transition zone (TZ), and the presumed circle area ratio (PCAR) [1,2] were calculated. Pulsatile blood flow was recorded, and the resistive index (RI) was calculated. Based on the serum concentration of total prostate specific antigen (PSA), ratio of PSA to prostate volume (PSAD), and ratio of PSA to TZ (PSAT) were calculated. Prostate tissues were obtained from 26 patients undergoing transurethral resection, suprapubic prostatectomy, or radical cystectomy, and were analyzed by quantitative morphometry. Computer image analysis was used to determine the mean area densities of the smooth muscle (SM), connective tissue (CT), glandular epithelium (GE) and lumen (GL), and vascular lumen (V). Correlations between ultrasonographic parameters and morphometric data were studied. RESULTS: On microscopic examination, the specimens showed a wide variety, ranging from normal prostate to typical glandular hyperplasia. There was a correlation between RI and the ratios of the four components (SM: r = -0.42 P = 0.034; CT: r = -0.42 P = 0.030; GE: r = 0.42 P = 0.032; GL: r = 0.46 P = 0.018). However, correlations between the other five transrectal parameters and the composition of the prostate were not so clear. This may have been because the blood vessels are compressed within the surgical capsule together with the urethra. CONCLUSIONS: The present study demonstrates that when RI is calculated by PDI, it can be quite useful for predicting component ratios, thereby making it possible to predict the therapeutic efficacy of alpha-blockers in individual patients.

Aged↗
PubMed2002

The HIV-1 Nef protein and phagocyte NADPH oxidase activation.

Nef, a multifunctional HIV protein, activates the Vav/Rac/p21-activated kinase (PAK) signaling pathway. Given the potential role of this pathway in the activation of the phagocyte NADPH oxidase, we have investigated the effect of the HIV-1 Nef protein on the phagocyte respiratory burst. Microglia (cell line and primary culture) were transduced with lentiviral expression vectors. Expression of Nef did not activate the NADPH oxidase by itself but led to a massive enhancement of the responses to a variety of stimuli (Ca(2+) ionophore, formyl peptide, endotoxin). These effects were not caused by up-regulation of phagocyte NADPH oxidase subunits. Nef mutants lacking motifs involved in the interaction with Vav and PAK failed to reproduce the effects of wild type Nef, suggesting a role for the Vav/Rac/PAK signaling pathway. The following results suggest a key role for Rac in the priming effect of Nef. (i) Inactivation of Rac by Clostridium difficile toxin B abolished the Nef effect. (ii) The fraction of activated Rac1 was increased in Nef-transduced cells, and (iii) the dominant positive Rac1(V12) mutant mimicked the effect of Nef. These results are to our knowledge the first analysis of the effect of Rac activation on the NADPH oxidase in intact phagocytes. Rac activation is not sufficient to stimulate the phagocyte NADPH oxidase; however, it markedly enhances the NADPH oxidase response to other stimuli.

Amino Acid Motifs↗
PubMed2002

Development of microsatellite markers from an ectomycorrhizal fungus, Tricholoma matsutake, by an ISSR-suppression-PCR method.

An inter-simple sequence repeat (ISSR)-suppression-PCR technique established to develop microsatellite markers of plant species was applied to an ectomycorrhizal fungus, Tricholoma matsutake. Six polymorphic SSR markers were developed. All six polymorphic SSR markers were single-locused and co-dominant. Alleles produced by these six single-locused markers ranged from two to nine per locus and the expected heterozygosities were calculated as values from 0.098 to 0.803. The results indicated that the ISSR-suppression-PCR technique was effective and applicable to the development of microsatellite markers from ectomycorrhizal fungi. Furthermore, the six microsatellite loci did not amplify DNA from any other ectomycorrhizal species investigated, except for Tricholoma nauseosum (Swedish matsutake) and Tricholoma fulvocastaneum, suggesting that population genetics and reproduction of T. matsutake could be investigated by the SSR markers developed in the present study.

Basidiomycota↗
PubMed2002

Bumblebee-pollination and temporal change of the calyx tube length in Clematis stans(Ranunculaceae).

Clematis stans is dioecious semi-arboreal, with pale purple-blue, nodding, tubulous flowers in a paniculate inflorescence. Both male and female flowers produce nectar from the base of the calyx tube during a flowering period of 3 or 4 days, and are pollinated by two bumblebee species, Bombus diversus and B. honshuensis,with different proboscis lengths. When the flowers open, four sepals constructing a calyx tube separate at the top and their respective tips gradually curl up, so that a tubular part shortens. Observations at two field sites showed that B. diversus (with a longer proboscis) most often visits the flowers with a longer calyx tube, and B. honshuensis (with a shorter proboscis) the flowers with a shorter calyx tube, i.e., later in the flowering period. By changing the calyx tube length, the flowers of C. stans accept the two bumblebee species with different proboscis length as pollinators and thus increase the chance of pollination for each flower. It was also found that the two bumblebee species prefer the male flowers to the female flowers, although the female flowers secrete more nectar as a reward than male flowers. This is likely because they visit the male flowers to collect pollen grains in addition to nectar.

Journal Article↗
PubMed2002

Critical role of myeloperoxidase and nicotinamide adenine dinucleotide phosphate-oxidase in high-burden systemic infection of mice with Candida albicans.

Oxygen metabolites generated by myeloperoxidase (MPO) and nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase contribute to microbial killing by phagocytes. To compare the importance of the 2 enzymes for host defense, MPO-deficient (MPO(-/-)) mice and NADPH-oxidase-deficient mice with chronic granulomatous disease (CGD mice) were intraperitoneally infected with 3 different doses of Candida albicans, and their infection severity was analyzed. CGD mice had increased mortality and exhibited increased tissue fungal burden in a dose-dependent manner, whereas normal mice showed no symptoms. Of interest, at the highest dose, the mortality of MPO(-/-) mice was comparable to that of CGD mice, but at the lowest dose, it was the same as that of normal mice. At the middle dose, the number of fungi disseminated into various organs of the MPO(-/-) mice was comparable to that of the CGD mice at day 6 of infection, but it was significantly lower at day 14. These results suggest that MPO and NADPH-oxidase are equally important for early host defense against a large inoculum of Candida.

Animals↗
PubMed2002

A 100-amino acid truncation in the cytoplasmic tail of glycoprotein 41 in the reference HIV type 1 strain RF.

Truncations of the cytoplasmic tail of the HIV-1 transmembrane (TM) protein are rare and almost always markedly reduce virus infectivity. We describe a truncation of the gp41 cytoplasmic tail in the commonly used early HIV-1 reference strain RF. This truncation apparently arose after continuous passage in H9 cells. We detected the truncation by Western blot as a size decrease in RF gp41 from 46 to approximately 34 kDa. The reduced size of RF gp41 observed was not due to differences in glycosylation. Viral DNA sequencing confirmed that a point mutation at Env residue 740 (Trp) introduced a premature stop codon, resulting in a 100-amino acid (13-kDa) truncation of the gp41 C terminus. This truncated RF species, termed RF(gp34), was characterized phenotypically by growth in Hut78 cells. Compared with other B clade HIV strains (IIIB, SF2, and NL4.3), RF(gp34) induced massive syncytia. Importantly, RF(gp34) also productively infected peripheral blood mononuclear cells in vitro.

Amino Acid Sequence↗
PubMed2002

Thymidine phosphorylase activity in renal cell carcinoma: relationship between histological parameters and chemosensitivity to fluorouracil-related drugs.

Thymidine phosphorylase (TdR-Pase) is an essential enzyme in the metabolism of fluorouracil-related drugs and is also a potent angiogenic factor. We measured the TdR-Pase activity in human renal cell carcinomas (RCCs) to assess the relationship between TdR-Pase activity and the degree of tumor malignancy. We also investigated the relationship between TdR-Pase activity and chemosensitivity to fluorouracil-related drugs. A total of 61 RCC tissue specimens and 39 normal kidney tissue specimens were obtained. TdR-Pase activity was measured by enzyme-linked immunosorbent assay. The in vitro histoculture drug response assay was also performed to examine tumor sensitivity to 5-fluorouracil (5-FU) and doxifluridine (5'-DFUR). The TdR-Pase activity of RCCs was 13-fold that of the normal tissues. Activity increased with histological grade, and,was significantly higher in high-stage tumors (T3 or higher). TdR-Pase activity exhibited a significant positive correlation with sensitivity to 5-FU and 5'-DFUR. High TdR-Pase activity in human RCC was confirmed to predict high tumor grade and stage. RCCs with high TdR-Pase activity were also sensitive to FU-related drugs.

Antimetabolites, Antineoplastic↗
PubMed2002

Saprobic potential of Tricholoma matsutake: growth over pine bark treated with surfactants.

Saprotrophic growth of Tricholoma matsutake isolates was investigated over Pinus densiflora bark fragments either on soil or on agar media. Preferential colonization of pine bark fragments by hyphae, in glucose-deprived environments suggested that Matsutake was able to extract some nutrients to sustain its growth. This was confirmed in glucose-free liquid nutrient medium, where bark as sole carbon source significantly stimulated (up to two-fold) growth of T. matsutake isolates. The addition of surfactants (Tween 80 and Tween 40) in liquid medium further stimulated mycelium growth over pine bark by up to 55%. Such growth stimulation was associated with a sharp increase in protein and beta-glucosidase excretion by hyphae in culture filtrates. As T. matsutake has some saprotrophic ability, the initiation and extension of Matsutake Shiro in forest soil might require simultaneously nutrients derived from the host plant and from soil organic compounds. Data reported here may contribute to the formulation of new culture substrates adapted to the co-culture of T. matsutake and its host plant under controlled conditions.

Agaricales↗
PubMed2002

Primary signet ring cell carcinoma of the urinary bladder successfully treated with intra-arterial chemotherapy alone.

A 65-year-old man presented with the complaint of gross hematuria. Cystoscopy revealed a sessile tumor on the left bladder wall. It was diagnosed as primary signet ring cell carcinoma of the bladder (T3bN0M0). The patient did not want surgical treatment. Therefore, three courses of arterial infusion of carboplatin were administered at 3-week intervals. Complete remission was obtained and has been maintained for 44 months. Our case appears to be the first report of successful treatment with chemotherapy alone of an infiltrating signet ring cell carcinoma of the bladder.

Aged↗
PubMed2002

Laparoscopic surgery for malignant adrenal tumors.

This paper outlines the indications and techniques of laparoscopic surgery for malignant adrenal tumors. Laparoscopic surgery is not indicated for adrenal tumors of any size when invasion of the surrounding tissues is clearly detected by preoperative imaging. When laparoscopic surgery is performed for a tumor without invasion that has a maximum diameter of more than 6 cm or a tumor that is considered potentially malignant from preoperative imaging or endocrine studies, it is important to inform the patient and family that the tumor may be malignant and that conversion to open surgery may be necessary. The transperitoneal approach is appropriate for primary adrenal malignancies. For metastatic cancer, the transperitoneal approach is suitable for radical surgery and the extraperitoneal approach for histological diagnosis by partial resection or tumor biopsy. In either case, it is important for the surgeon to have a sufficiently wide working space, to remove the tumor and surrounding fat en bloc, to never grasp the tumor or adrenal tissue, and to carefully handle the ultrasonically activated scalpel or ultrasonic aspirator so that it does not touch the tumor surface due to the risk of tumor cell dissemination. It is also essential not to unreasonably persist with laparoscopic procedures, but to immediately switch to open surgery when laparoscopic surgery becomes difficult.

Adrenal Gland Neoplasms↗
PubMed2002

Role of Doppler ultrasound and resistive index in benign prostatic hypertrophy.

BACKGROUND: The aim of the present study was to assess the resistive index in patients with benign prostatic hypertrophy (BPH) and the role of power Doppler ultrasonography. METHODS: From April 1996 to December 1997, a total of 214 men aged 48-86 years with symptoms of BPH were prospectively enrolled to participate in our study. All patients presented to our clinic with lower urinary tract symptoms. Transrectal ultrasonography was used to calculate the total prostate volume (TPV), transition zone (TZ) volume, transition zone index (TZI = TZ volume/TPV) and presumed circle area ratio (PCAR). Power Doppler imaging was used to identify the capsular and urethral arteries of the prostate and measure its resistive index (RI) value. RESULTS: The RI of capsular arteries significantly correlated with theTPV, TZ volume, TZI (r = 0.470; P < 0.0001) and PCAR (r = 0.334; P < 0.0001). Correlations were found between the RI of capsular arteries and the International Prostatic Symptom Score (IPSS) (r = 0.389; P < 0.0001), peak flow rate of uroflowmetry (r = -0.393; P < 0.0001). CONCLUSION: We demonstrated that an increase of the RI of capsular arteries correlated with increases in the TZI and PCAR in BPH. The lower IPSS and peak flow rate correlated with the high RI of capsular arteries; however, no correlation between the RI of urethral arteries and prostatic parameters was found. The findings suggested that the RI of capsular arteries may become the index for measuring lower urinary obstruction in the future.

Aged↗
PubMed2002

Histologically benign but telomerase positive adrenal pheochromocytoma.

Adrenalectomy was performed on a 37-year-old woman with right adrenal pheochromocytoma. Although the histological diagnosis was benign, telomerase repeat amplification protocol (TRAP) demonstrated positive telomerase activity. Thirty-five months after adrenalectomy, a recurrent tumor was found. Forty-seven months after adrenalectomy, bone metastases also appeared. Malignant pheochromocytoma was clinically diagnosed. Our experience suggests that telomerase-positive tumor cells are highly likely to repeat cell proliferation when they are left in the patient's body, and lead to recurrence. Therefore, telomerase-positive tumors should be clinically treated as malignant even if they have been histologically diagnosed as benign.

Adrenal Gland Neoplasms↗
PubMed2002

Meta-analysis on the therapeutic state of hypertensive population in Japan: focusing on the impact of new diagnostic criteria of Japanese Guideline for the Management of Hypertension 2000.

A Meta-analysis on the therapeutic state of hypertensive population in Japan is performed by the three nation-wide governmental surveys focusing on the impact of new diagnostic criteria described in the Guidelines for the Management of Hypertension in Japan 2000. These surveys are the National Survey of Circulatory Disorders, National Nutrition Survey and Patient Survey in 1990. The meta-analysis approach is used to evaluate the validity and reliability of these three national data sets, particularly the National Nutrition Survey. The population with history of hypertensive treatment and without previous diagnosis was calculated using the old and new diagnostic criteria. The results of three national surveys are fairly consistent. National Nutrition survey can be used to monitor the overall therapeutic status of Japanese population if the definition is considered judiciously. The impact of new diagnostic criteria is extensive as demonstrated by the results of the analysis on the National Nutrition Survey of 1999. The hypertensive population doubled and one half of the Japanese population over the age of 30 is now defined as hypertensive. A policy to manage this newly diagnosed hypertensive population is urgently needed to lessen the burden on Japanese health care system.

Adult↗
PubMed2002

[Contribution of neutrophils to Aspergillus infection].

Neutrophil disfunction, caused by a decreased production of effective radical oxygen species by myeloperoxidase (MPO) and NADPH oxidase within the neutrophil, may result in susceptibility to opportunistic fungal infections. In vitro, MPO produces OCl, which kills bacteria and viruses. In the case of MPO deficiency, susceptibility to Candida albicans infection was observed. Furthermore, it was demonstrated that MPO knockout mice were primarily susceptible to C. albicans infection. With regards to NADPH oxidase deficiency, such a patient was found to have severe chronic granulomatous disease (CGD) due to Aspergillus infection. This deficiency may have resulted from a gene mutation and/or abnormality of the NADH oxidase components, particularly cytochrome b558 (gp91phox and p22phox) in membrane and cytosol factors p47phox, p67phox, p40phox and others in neutrophil. Thus,irregular regulation of transcription factors for gene expression of phox molecules and MPO permits susceptibility to Aspergillus and Candida infections.

Animals↗
PubMed2002

[Sling suspension of incontinent urinary reservoir].

We report a case and surgical technique of successful sling suspension of insufficient efferent limb of continent urinary reservoir, which has occurred urinary incontinence. A 64-year-old male, who received radical cystectomy with continent urinary reservoir, had been suffered urinary incontinence from the reservoir about one year after surgery. Various procedures, such as the repair of the efferent limb of the reservoir, addition of the ileal patch, instillation of scopolamine, oxybutynin into the reservoir and an injection of GAX collagen in the efferent limb, were not effective for his urinary incontinence. Finally, anti-incontinence procedure of sling at an efferent limb using abdominal rectus muscle fascia was employed and obtained a continence for 2 years after operation. The principle of this surgery is same with that of sling suspension for female stress incontinence. It is advisable for the incontinent urinary reservoir when it has an enough length of efferent limb.

Humans↗
PubMed2002

[A case of interstitial pneumonia exacerbated by kampo-induced pneumonitis].

A 65-year-old woman who had complained of non-productive cough since May 1998 visited our hospital on November 5, 2000. She had been treated at another hospital with Kampo (Chinese herbal medicine), including Moku-boui-to, Bakumon-do-to, and Saiko-keishi-kankyo-to for chronic non-productive cough. Chest radiographs and CT films showed the reticular shadows that had been present in 1998, in both lower lung fields, and also demonstrated new reticular shadows in the right upper lung field and left lingular segment. Laboratory data revealed hypoxemia and pulmonary function tests revealed restrictive ventilatory disturbance, so she was admitted to our hospital on November 9, 2000. After the cessation of Kampo treatment, her symptoms disappeared, and the hypoxemia, restrictive disturbance, and reticular shadows in the chest radiograph gradually improved. Video-assisted lung biopsy specimens showed thickened alveolar walls with lymphocyte and eosinophil infiltration. A leukocyte migration test was positive for Moku-boui-to, Bakumon-do-to, and weakly positive for Saiko-keishi-kankyo-to. Although no challenge test for Kampo was performed, we diagnosed this case as interstitial pneumonia exacerbated Kampo-induced pneumonitis based on these clinical, laboratory and histological findings.

Aged↗