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991.
Makoto Ohnishi Yuko Watanabe Emi Ono Chieko Takahashi Hitomi Oya Toshiro Kuroki Ken Shimuta Norio Okazaki Shu-ichi Nakayama Haruo Watanabe 《Antimicrobial agents and chemotherapy》2010,54(3):1060-1067
In Neisseria gonorrhoeae, the mosaic type of penA, which encodes penicillin-binding protein 2 (PBP 2), is associated with reduced susceptibility to oral cephalosporins. To investigate the relatedness of N. gonorrhoeae clinical isolates with reduced susceptibility, we sequenced the penA genes of 32 isolates. Five different amino acid sequence types of PBP 2 were identified, but all seemed to be derivatives of pattern X of PBP 2 (PBP 2-X). However, multilocus sequence typing of the isolates showed that the isolates belonged to six different sequence types. As PBP 2-X was identified in three different sequence types, horizontal transfer of the penA allele encoding PBP2-X was suggested. We demonstrated that the penA gene could be transferred from an isolate with reduced susceptibility to a sensitive isolate by natural transformation. Comparison of the sequence of the penA-flanking regions of 12 transformants with those of the donor and the recipient suggested that at least a 4-kb DNA segment, including the penA gene, was transferred. During horizontal transfer, some of the penA alleles also acquired variations due to point mutations and genetic exchange within the allele. Our results provide evidence that the capacity for natural transformation in N. gonorrhoeae plays a role in the spread of chromosomal antibiotic resistance genes and the generation of diversity in such genes.Neisseria gonorrhoeae is one of the most common sexually transmissible infective agents. Humans are the only natural host for N. gonorrhoeae, and transmission is restricted to direct person-to-person sexual contact. As there is no vaccine for gonorrhea, the control of dissemination depends on timely identification and initiation of an appropriate antibiotic treatment for the infected person in order to prevent transmission.N. gonorrhoeae strains that are resistant to various types of antibiotics have emerged, causing critical concern for public health around the world. Resistance to oral cephalosporins, such as cefixime, is emerging (2, 3, 10, 18), and approximately 30% of N. gonorrhoeae isolates in Japan now show reduced susceptibility to cefixime (20). The molecular mechanism of resistance has been elucidated as the formation of a mosaic structure of penA-encoded penicillin-binding protein 2 (PBP 2). The mosaic penA was generated by interspecies recombination with other neisserial species (3, 10), which is the same mechanism for chromosomally mediated penicillin resistance in N. gonorrhoeae (23). However, the precise junctions of recombination have not been fully elucidated.penA-encoded PBP 2 proteins of N. gonorrhoeae are divided into several types on the basis of the amino acid sequence, and some of these types are associated with reduced susceptibility to cefixime (10, 14, 25, 27). Among these, the most common PBP 2 type is pattern X (PBP 2-X), implying the expansion of a single clone. According to the spread of isolates with reduced susceptibility to cefixime, the expansion of a single clone, which emerged at an early phase, is suggested (18). However, another possibility is that recombination of the penA gene occurred several times independently, followed by multiclonal expansion. Understanding of the mode of spread of antibiotic-resistant clones could help us construct a public health strategy for preventing the further spread of resistant clones.To investigate the mode of dissemination of the newly emerged antibiotic-resistant N. gonorrhoeae isolates, we retrospectively characterized isolates with reduced susceptibility to cefixime (cefixime MIC ≥ 0.25 μg/ml, referred to hereafter as CefRs isolates), using penA sequencing and multilocus sequence typing (MLST) with seven housekeeping genes. We also examined whether the horizontal transfer of penA occurred in vitro, resulting in the one-step emergence of CefRs isolates from the susceptible isolate. 相似文献
992.
Gou Kaneko Eiji Kikuchi Masanori Hasegawa Akira Miyajima Ken Nakagawa Kaori Kameyama Mototsugu Oya 《International journal of clinical oncology / Japan Society of Clinical Oncology》2010,15(6):626-630
A 74-year-old female was referred to our hospital for non-muscle invasive bladder tumors initially treated at another hospital.
Preoperatively, computed tomography and magnetic resonance imaging demonstrated non-muscle invasive bladder tumors and a vaginal
tumor. A second transurethral resection of the bladder tumors, transvaginal tumor resection, and systemic chemotherapy were
performed. The histopathological appearances of both tumors were very similar and the diagnoses were urothelial carcinoma
(UC). The pathogenesis of the vaginal UC was considered to be the primary UC or metastasis from the bladder UC. Vaginal UC
is extremely rare and this is only the 15th report in the literature. 相似文献
993.
Keisuke Shigeta Eiji Kikuchi Masayuki Hagiwara Toshiyuki Ando Ryuichi Mizuno Akira Miyajima Ken Nakagawa Mototsugu Oya 《Surgical oncology》2017,26(1):73-79
Objective
To evaluate the impact of pneumoperitoneum time on intravesical recurrence (IVR) in upper tract urothelial carcinoma (UTUC) patients who underwent laparoscopic radical nephroureterectomy (LRNU).Patients and methods
We identified 129 UTUC patients who underwent LRNU at our three institutions from 2004 to 2014. We evaluated the association of IVR rate and patient clinico-pathological characteristics including operation time. By retrospectively reviewing all videotapes, we defined pneumoperitoneum time as being from the infusion of pressurized CO2 gas with a pressure of 10–12 mmHg to extirpation of the kidney.Results
During the median follow-up of 31.1 months, 61 (47.3%) had subsequent IVR after LRNU. Multivariate analysis revealed that prolonged pneumoperitoneum time (HR = 1.81, p = 0.025) and presence of lymphovascular invasion (LVI) (HR = 1.53, p = 0.006) were independent risk factors for subsequent IVR. The 3-year and 5-year IVR free survival rates were 43.7% and 21.8% in patients with a prolonged pneumoperitoneum time of ≥150 min, which were significantly lower than those in their counterparts (59.0% and 48.3%, respectively, p = 0.024). The subsequent IVR rates were 27.3% for a pneumoperitoneum time of <90 min, 35.8% for that of 90–150 min, 55.0% for that of 150–210 min, 61.1% for that of 210–270 min, and 85.7% for that of >270 min.Conclusions
Prolongation of pneumoperitoneum time and presence of LVI might be associated with higher risk of subsequent IVR in UTUC patients who underwent LRNU. 相似文献994.
Pinar Özcan Cem Fiçicioğlu Seda Ateş Meltem Güner Can Çiğdem Kaspar Oya Akçin 《Gynecological endocrinology》2017,33(6):467-471
Objective: The main purpose of our study is to categorize starting doses of recombinant follicle-stimulating hormone (recFSH) based on various cutoff values of anti-Mullerian hormone (AMH) and to determine the effectiveness of serum AMH levels in the prediction of poor ovarian response.Material and methods: Prospective data analysis was conducted at IVF center. A total of 323 patients were included. All patients were divided into four groups according to the patients’ serum AMH concentrations: Group 1 (AMH?1?ng/ml; 450?IU/day n?=?157); Group 2 (AMH 1–2?ng/ml; 375?IU/day, n?=?55); Group 3 (AMH 2–3?ng/ml; 225?IU/day, n?=?48); and Group 4 (AMH?>?3?ng/ml; 150?IU/day, n?=?63). Collected data included age, total gonadotropin dosage, duration of stimulations, the total number of oocytes retrieved, ovarian response, cancelation rate, and cPRs.Results: As serum AMH levels increased, there were significant decreases in the starting recFSH dose and total gonadotropin dosage, and a significant increase in the total number of oocytes retrieved. There was a significant trend toward increasing cycle cancelation rates and decreasing cPRs with decreasing serum AMH levels. Although there were no significant differences with regard to the proportion of cycles with hypo-response between all groups. A result of ≤0.83 was considered the cutoff value of AMH to predict a hypo-response to ovarian stimulation.Conclusions: AMH is a useful marker in selecting the starting dose of recFSH and prediction of poor ovarian response. Our protocol may allow clinicians to modulate the starting dose of recFSH according to these cutoff values for serum AMH levels. 相似文献
995.
Ryuichi Mizuno Jun Nakashima Makio Mukai Hajime Okita Michio Kosugi Eiji Kikuchi Akira Miyajima Ken Nakagawa Takashi Ohigashi Mototsugu Oya 《BJU international》2009,104(9):1215-1218
OBJECTIVE
To investigate the possible significance of tumour dimensional variables, including maximum tumour diameter (MTD), maximum tumour area (MTA) and total tumour volume (TTV), with standard prognostic factors for predicting prostate‐specific antigen (PSA) recurrence after radical prostatectomy (RP).PATIENTS AND METHODS
Serial whole sections of the prostate from 164 patients who had RP for localized prostate cancer were investigated. Cox proportional hazards regression models were used for univariate and multivariate analyses to test the relationships between biochemical failure and clinicopathological factors, including tumour dimensional variables. The results were analysed retrospectively to develop a prognostic factor‐based model for risk stratification.RESULTS
In the univariate Cox proportional hazard model, pathological T stage, Gleason score, perineural invasion, microvascular invasion, positive surgical margins, MTD, MTA and TTV were significantly associated with biochemical failure. In the multivariate Cox proportional hazard model using a stepwise inclusion of these factors, Gleason score, positive surgical margins and MTD were independent indices in association with biochemical failure. Using the three statistically significant variables, the relative risk of biochemical failure could be calculated.CONCLUSION
These results imply that MTD is possibly one of the most important prognostic factors for predicting biochemical recurrence after RP. As calculating the MTD on the section a rapid, simple and objective method, it can be used instead of the TTV calculation. The prognostic factor‐ based risk stratification might help clinicians to predict biochemical failure after RP. 相似文献996.
M Matsushima M Horinaga R Fukuyama H Yanaihara E Kikuchi M Kawachi M Iida Y Nakahira M Oya H Asakura 《Oncology letters》2011,2(1):13-19
Intravesical immunotherapy with bacillus Calmette-Guerin (BCG) is currently the most successful adjuvant agent for the treatment and/or prophylaxis of non-muscle-invasive bladder cancer (NMIBC). However, NMIBCs recur in 60-70% of cases and 30% of these recurrent tumors present with a higher grade and more invasive properties. Patients that do not respond to intravesical BCG therapy are considered to be a challenge for urologists. Thus, novel conservative possibilities should be explored. To test the efficacy of a novel therapeutic approach, we examined the antitumor effect of combination therapy by intravesical administration of mitomycin C (MMC) plus BCG, infusing the two drugs simultaneously, in an orthotopic bladder cancer model. Intravesical BCG and MMC administration showed a dose-dependent survival (n=8 per group). The combination of MMC and BCG provided a significant survival advantage compared to the BCG-alone (p=0.035) and MMC-alone groups (p=0.040) (n=8 per group). The group with combined MMC/BCG exhibited a survival period similar to that achieved with an amount eight times higher that of BCG (n=10 per group). Ki-67 labeling index of cancer cells, showing tumor proliferation, was significantly lower in the combined group compared to the BCG-alone (p<0.05), MMC-alone (p<0.01) and control groups (p<0.01). No difference was detected between the combined group and the BCG-alone group with regard to CD3, T-cell infiltration and CD68 macrophage activity. The combined MMC/BCG treatment decreased the tumor appearance rate, improved the survival period and reduced the cellular proliferation rate in tumors compared to the BCG-alone treatment. The results suggest that the combined intravesical MMC/BCG treatment induced an enhanced antitumor effect against bladder tumors. The combined MMC/BCG treatment also showed a survival period similar to that achieved using a dose eight times higher of BCG-alone. 相似文献
997.
Nogawa H Horikoshi H Oya N Akiyoshi T 《Gan to kagaku ryoho. Cancer & chemotherapy》2011,38(10):1717-1722
Hepatic artery chemotherapy with transarterial infusion (TAI) of a cisplatin formulation designed for intra-arterial injection (IA-call?) is recognized as an established treatment for advanced hepatocellular carcinoma (HCC). We experienced three patients whose multiple HCC(Stage III) was successfully treated by TAI using IA-call combined with embolization by porous gelatin particles (Gelpart?), after a series of treatments such as hepatectomy, radiofrequency ablation (RFA), transcatheter arterial chemoembolization (TACE), and TAI. Cisplatin-based TAI was not effective, but porous gelatin particles showed a therapeutic effect in one patient by reducing his hepatic arterial blood flow. The two other patients responded to combination therapy after the second treatment. Adverse events from the treatment were mild. This therapy has benefits even for multiple intra-hepatic lesions that are resistant to TACE and TAI because of its widespread effect on the entire liver, and it could be an effective treatment option for advanced HCC. 相似文献
998.
Tanaka T Okanobu H Kuga Y Yoshifuku Y Fujino H Miwata T Moriya T Nishida T Oya T 《Gastroentérologie clinique et biologique》2010,34(12):687-695
Background and Objective
Elevated/activated myeloid leucocytes, like the CD14(+)CD16(+) monocytes are sources of TNF-α, and therefore, selective depletion of these cells by granulocyte/monocyte (GM) adsorption (GMA) should promote remission or enhance drug efficacy. However, studies in ulcerative colitis (UC) reported contrasting efficacy, from an 85% to statistically insignificant level. We investigated patients’ demography in responders and non-responders.Methods
In 120 UC patients, 61 steroid naive and 59 steroid dependent, we looked for entry clinical or endoscopic features to identify responders (or non-responders) to GMA. Patients received up to an 11 Adacolumn GMA sessions over 12 weeks. Patients were clinically and endoscopically evaluated, allowing each patient to serve as her/his own control. Immunohistochemistry on colonic biopsies was to reveal the impact of GMA on leucocyte infiltration of the mucosa.Results
Entry average clinical activity index (CAI) was 12.6, 10–16. An 80 of 120 patients responded (CAI ≤ 4); 45 steroid naïve (73.8%) and 35 steroid dependent (59.3%). Over 900 biopsies were processed. Infiltrating leucocytes were overwhelmingly polymorphonuclear and macrophages around and within crypt abscesses. There was a marked reduction of infiltrating leucocytes in responders. Most non-responders had extensive colonic lesions with virtually no mucosal tissue left at the lesions.Conclusions
Steroid naïve patients with short duration of UC were the best responders, while patients with deep colonic lesions and extensive loss of the mucosal tissue were non-responders. 相似文献999.
Gastrointestinal stromal tumor (GIST) is one of the most common malignant mesenchymal tumors of the stomach. Prognosis of this disease is related to tumor size and mitotic activity and early diagnosis is the only way to improve it. Diagnosis of GIST always requires histological and immunohistochemical confirmation as no imaging modalities can diagnose it conclusively. Endoscopic forceps biopsy results are frequently negative. Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is a technique which allows tissue samples to be obtained with minimal risks and is accurate in the diagnosis of GIST. From the point of view of the endoscopist, aggressive use of EUS-FNA is the only promising way to allow early diagnosis and early treatment of this disease. 相似文献
1000.
Ciledag A Karnak D Kayacan O 《The Southeast Asian journal of tropical medicine and public health》2010,41(4):900-903
Abstract. We report here a 35 year-old immunocompetent male, with a fulminantly lethal diffuse alveolar hemorrhage caused by CMV pneumonia. The patient was admitted with fever, rust colored sputum and exertional dyspnea. A chest x-ray revealed bilateral alveolar infiltration in a butterfly pattern. Bronchoalveolar lavage (BAL) was performed which revealed alveolar hemorrhage. Microscopic findings of the lavage fluid revealed large numbers of erythrocytes and hemosiderin-laden macrophages. The patient did not improve with empiric antibiotic treatment. High CMV IgG and IgM titers were found in the serum. The patient died from respiratory failure after detection of inclusion bodies on BAL before initiation of antiviral therapy. 相似文献