Biofilm Bacterial Dynamics and Changes in Inorganic Nitrogen Density Due to the Presence of Freshwater Pearl Mussels.

The freshwater pearl mussel (genus Margaritifera) has shown severe declines, while the mussels play important roles in the translocation of nutrients and materials in river water ecosystems. We hypothesized that the biofilm bacterial composition and nutrient flow may reflect the differences in the existence of mussels. We analyzed water from 14 rivers from in multiple regions of Japan, including eight rivers, where the two species of freshwater pearl mussels (Margaritifera laevis and Margaritifera togakushiensis) are predominantly found, to analyze the microbial and nutritional nature of the biofilm artificially formed in the river. Field-produced biofilms, including the bacterial community structure, were examined, using next-generation sequencing of bacterial 16S rRNA gene amplicons followed by analyzing the genomic DNA extracted from the samples, inorganic nitrogen compounds, and chlorophyll a concentration. Compared to those in the control river without freshwater pearl mussels, biofilms of the existing river contained less inorganic nitrogen (ammonia and nitrate), suggesting the involvement of mussels in regulating the river water nutrient flow. Distinct changes were found in biofilms, depending on mussel existence, particularly in biofilms containing fewer photosynthetic bacterial groups, such as Betaproteobacteria and Cyanobacteria. Conversely, bacteria belonging to Bacteroidales in Bacteroidetes and Clostridiales in Firmicutes were predominantly found in biofilm samples where the mussels existed. Mussels alleviated strict nitrogen limitation in streams and possibly caused a concomitant change in the bacterial communities, where populations of bacterial groups exchanging inorganic nitrogen were low. We demonstrate the profound influence of freshwater mussel species on ecosystem processes and community dynamics across rivers. IMPORTANCE The abundance of freshwater unioid mussels exhibited more diverse patterns of inorganic nitrogen flow and bacterial communities than the areas without mussels. This study demonstrates the effect of mussels on different freshwater ecosystem processes with variable organismal densities and biogeochemical factors. Freshwater unionid mussels significantly affect the ecosystem and community dynamics by modulating the relationships, altering nutrient availability, and indirectly manipulating the downstream ecological members, eventually expanding their role in the river ecosystems.

Ureteral reconstruction with bowel segments: experience with eight patients in a single institute.

PURPOSE: Although replacement of the ureter with a bowel segment is indicated for large ureteral defects, it is still a challenging technique for urologists. We present our experience and outcome of ureteral reconstruction using bowel segments. MATERIALS AND METHODS: Ureteral reconstruction with bowel segments was performed in eight patients in our institute between 1969 and 2009. We investigated the position and length of the ureteral defect and methods of reconstruction as well as the patients' backgrounds, postoperative complications, and clinical outcomes. RESULTS: Five patients underwent ureteral replacement with isolated ileal segments alone. In one patient, the ureter was reconstructed by using the Yang-Monti procedure with the ileum. A colon segment was used in two patients who required bladder augmentation for tuberculous contracted bladder at the same time. Metabolic acidosis occurred in three patients having a solitary kidney and the ureter had to be replaced by a relatively long intestinal segment. Two patients who received preoperative radiation therapy were required to undergo additional operations. Long-term cancer-free survival was achieved in one patient who underwent ileal substitution for low-grade renal pelvic cancer. CONCLUSIONS: Although ureteral replacement with a bowel segment is a challenging and useful procedure, attention must be paid to the possibility of metabolic acidosis, which is likely to occur in patients having a solitary kidney with renal insufficiency or in patients requiring a long intestinal segment for reconstruction. In addition, preoperative radiation therapy for the pelvic organs may cause postoperative complications.

Impact of visceral fat ratio on sleep-related erection: a retrospective study of elderly patients.

OBJECTIVES: To investigate the impact of visceral fat accumulation on the preoperative erectile function of elderly patients undergoing radical prostatectomy. METHODS: A total of 83 patients who underwent radical prostatectomy from August 2005 through August 2013 were included in the present study. Findings at preoperative computed tomography scanning and sleep-related erection were used to determine the objective erectile function. Sleep-related erection was measured with an erectometer during at least three nights, and we assessed the maximum penile circumferential change. The visceral fat ratio was calculated as the ratio of the visceral fat area to the total subcutaneous fat area on computed tomography images, and the influence of these parameters on preoperative erectile function was assessed. RESULTS: In simple linear regression analysis there was a strong correlation between the waist circumference and visceral fat ratio (P < 0.01). A visceral fat ratio of 55% was equivalent to a waist circumference of 85 cm, which is the standard value for central obesity in Japan. Furthermore, the factor that most negatively affected maximum penile circumferential change was the visceral fat ratio. In addition, only a visceral fat ratio of 55% or greater was a significant independent risk factor for declining maximum penile circumferential change in both univariate and multivariate analyses (P = 0.04 and 0.02, respectively). CONCLUSIONS: The present study is the first to show the utility of the visceral fat ratio as an index of central obesity and the relationship with sleep-related erection in elderly men.

[Clinical and pathological features of the best candidates for active surveillance-retrospective analysis of patients with radical prostatectomy].

To develop a more clinically relevant protocol and identify the best candidates for active surveillance (AS), we examined the pathological features of radical prostatectomy (RP) specimens of patients who met the Japanese AS protocol criteria. Of 342 patients who underwent RP between 2000 and 2010, 58 (17.0%) eligible for the Japanese AS protocol were retrospectively identified. Pathological features of biopsy specimens and RP specimens were compared to reveal the incidences of up-grading, up-staging and insignificant cancer. We also tried to identify preoperative clinical and pathological factors that accurately predicted the insignificant cancer in the surgical specimens. Up-grading (Gleason score ≥7) and upstaging (≥pT3) were observed in 32 (55.2%) and 6 (10.3%) patients, respectively. Insignificant cancer was observed in 19 (32.8%). Dominant tumors were located in the peripheral zone (PZ) in 34 (58.6%) patients and in the transition zone (TZ) in 24 (41.4%). Multivariate analysis revealed that prostate-specific antigen density ＜0.15 ng/ml/cm3 was a significant independent factor to predict insignificant cancer (odds ratio 6.70, p＝0.036). Larger dominant tumors were associated more frequently with up-grading and up-staging (p=0.038 and p=0.021, respectively), and were more likely to be located in the TZ (P = 0.027). Our results suggest that the risk of up-grading and up-staging should be considered in patients who met the Japanese protocol. Larger dominant tumors were associated more frequently with up-grading and up-staging.

Clinical evaluation of hemorrhagic gastroduodenal ulcer in the elderly: is Helicobacter pylori infection a risk factor for hemorrhage?

AIM: In this study, the aim was to determine the demographic characteristics of elderly patients with gastroduodenal ulcer who had undergone endoscopic hemostasis by comparing them with younger patients. METHODS: A total of 353 patients with Forrest class I-IIa hemorrhagic gastroduodenal ulcer who underwent endoscopic hemostasis at our hospital between December 2004 and May 2010 were divided into two groups: one for those 75 years or older (old-old group; n = 71; age ≥75 years) and one for those younger than 75 years (younger group; n = 282; age <75 years). Then, their demographic characteristics were compared. RESULTS: There were significantly more female patients, patients with underlying chronic renal failure and patients using non-steroidal anti-inflammatory drugs in the old-old group than in the younger group. In addition, the prevalence of open-type atrophy in the background gastric mucosa was significantly higher in the old-old group. Although more than half the patients in each group were infected with Helicobacter pylori, the prevalence was significantly higher in the younger group. Of the patients who underwent endoscopic hemostasis only once, those in the old-old group constituted a significantly higher medical cost than those in the younger group. Comparison of deaths between the two groups revealed that the old-old patients were more likely to develop severe complications associated with hematemesis, such as aspiration pneumonia. CONCLUSIONS: The observed lower prevalence of Helicobacter pylori infection among the elderly patients compared to the younger patients with hemorrhagic gastroduodenal ulcer suggests that other factors, such as non-steroidal anti-inflammatory drugs use and chronic renal failure, predispose the elderly to hemorrhagic ulcer.

[A case of Crohn's disease developing bladder rupture 4 months after laparoscopic sigmoidectomy with partial cystectomy for vesicosigmoidal fistula].

A 32-year-old well-nourished man having a vesicosigmoidal fistula due to Crohn's disease received laparoscopic sigmoidectomy with partial cystectomy. The bladder wall was closed with an all-layer running suture and additional interrupted sutures using 2-0 Vicryl. Four months after surgery, the suture site on the bladder showed perforation to the abdominal cavity. Since the same event occurred again 6 months after surgery, open partial cystectomy was performed to repair the perforated site 8 months after the initial surgery. The perforated site showed a thinning bladder wall composed of normal urothelium, scar tissue and thin detrusor muscle. Non-caseating granuloma was not found in the specimen, even though it was slightly observed in the margin of the detrusor muscle resected in the initial surgery. Although it was possible that the persisting activity of Crohn's disease, subclinical impaired nutrition due to Crohn's disease or insufficient suturing of the bladder wall were involved in the bladder rupture, the definitive cause remains unknown.

Baseline erectile function alters the cavernous nerve quantity and distribution around the prostate.

PURPOSE: We clarified the distribution of neuronal nitric oxide synthase positive nerve fibers around the prostate and factors contributing to fiber quantity. MATERIALS AND METHODS: We investigated 46 hemispheres of 23 nonnerve sparing radical prostatectomy specimens from patients with available preoperative International Index of Erectile Function and maximum penile circumferential change data. We performed immunohistochemical staining with neuronal nitric oxide synthase antibody, and divided the prostatic hemisphere into 6 zones to assess the distribution of neuronal nitric oxide synthase positive nerve fibers at the apex, midportion and base of the prostate. Multivariate analysis of the quantity of overall neuronal nitric oxide synthase positive nerve fibers used the variables of specimen weight, patient age, body mass index, International Index of Erectile Function and maximum penile circumferential change. A maximum penile circumferential change of 20 mm or less was considered objective erectile dysfunction. RESULTS: Median patient age was 68 years (range 57 to 74). Median International Index of Erectile Function-erectile function domain score was 12 (range 0 to 24) and median maximum penile circumferential change was 25.0 mm (range 2.70 to 38.3). Of the neuronal nitric oxide synthase positive nerve fibers 65% were distributed in a 3 to 5 o'clock sextant (p <0.001). Logistic regression analysis revealed that maximum penile circumferential change was the single significant variable (p = 0.019). The fiber count was greater in the objective erectile dysfunction group (median 1,500, range 382 to 2,760) than in the nonerectile dysfunction group (median 649, range 156 to 2,916) (p = 0.009). The fiber count was significantly different between the 2 groups in the 3 to 6 o'clock area, especially at the apex. CONCLUSIONS: Baseline erectile function greatly impacts cavernous nerve quantity and distribution. Cavernous nerve preservation in the neurovascular bundle, especially at the apex, is still essential for patients with erectile dysfunction.

Contemporary patients with LUTS/BPH requiring prostatectomy have long-term history of treatment with alpha1-blockers and large prostates compared with past cases.

OBJECTIVES: To retrospectively investigate the characteristics of patients with lower urinary tract symptoms suggestive of benign prostatic hyperplasia for which surgery was needed during the past 20 years. In particular, the chronologic change in prostate volume at surgery and the status of alpha(1)-blocker use before surgery and its duration were studied. METHODS: The data from 371 consecutive patients with lower urinary tract symptoms/benign prostatic hyperplasia who had undergone surgery in our institute from 1987 through 2006 were retrospectively analyzed. The number of surgeries, type of surgical procedure, content and duration of medical treatment of lower urinary tract symptoms/benign prostatic hyperplasia before surgery, prostate volume on transrectal ultrasonography at baseline and at surgery, and the weight of the removed tissue were determined from the medical charts. RESULTS: The number of surgeries suddenly began to decrease between 1987 and 1990 and again from 1991 to 1994, probably owing to the introduction of 2 nonselective alpha(1)-blockers at those times in Japan. The percentage of use of alpha(1)-blockers before surgery and the duration of use increased in each period. More than 80% of recent patients had received alpha(1)-blockers before surgery, with an average duration of 3 years. Recent patients had a large prostate volume at baseline and at surgery compared with previous patients. Corresponding to the large prostate, open subcapsular prostatectomy was indicated in 18% of the recent patients. CONCLUSIONS: Patients with surgical treatment after long-term use of alpha(1)-blockers had large prostates at baseline and at surgery. Although alpha(1)-blockers delayed the need for surgery by a few years, patients with a large prostate volume might finally need to undergo surgery.

Measurement of plasma concentration of gemcitabine and its metabolite dFdU in hemodialysis patients with advanced urothelial cancer.

OBJECTIVE: We investigated the pharmacokinetics of gemcitabine and its metabolite in two male patients (52 and 56-year-old) with advanced urothelial cancer receiving hemodialysis three times a week. METHODS: Gemcitabine, 1000 mg/m(2) in 100 ml of saline, was intravenously administered for 30 min. The concentration of gemcitabine and its metabolite 2',2'-difluorodeoxyuridine (dFdU) was measured at several given time points using a high-pressure liquid chromatography assay. Pharmacokinetic parameters were determined using the two-compartment modeling program. RESULTS: Gemcitabine was rapidly eliminated from plasma even in patients with renal dysfunction. No obvious differences in pharmacokinetic parameters such as the t(1/2), AUC and C(max) of gemcitabine were observed between the patients on hemodialysis and those with normal renal function in previous reports. On the other hand, dFdU showed a sustained level until hemodialysis was initiated. Hemodialysis could reduce the plasma dFdU level by approximately 50%. CONCLUSIONS: According to the previous information, no dose modification of gemcitabine may be required for patients with renal impairment or hemodialysis. However, gemcitabine should be given with caution because only limited information is available, and the clinical effect of sustained and/or accumulated dFdU is unknown.

Appearance of osteonectin-expressing fibroblastic cells in early rat stomach carcinogenesis and stomach tumors induced with N-methyl-N'-nitro-N-nitrosoguanidine.

The present study was designed to define molecular alterations in the initiation stage of rat stomach carcinogenesis. Groups of male Lewis rats, 6 weeks old, were given drinking water with or without N-methyl-N'-nitro-N-nitrosoguanidine (MNNG; 100 mg/liter). Total RNA was isolated from the stomach pyloric mucosa, and fluorescent differential display analysis was performed. A cDNA fragment of 125 bp encoding an extracellular matrix-associated matricellular glycoprotein, osteonectin, was identified after 14 days of MNNG exposure. A severalfold increase in expression was observed after 14 and 27 days of MNNG exposure, as determined by northern blot and RT-PCR. Immunohistochemistry revealed that osteonectin-mAb-stained fibroblastic cells appeared in interstitial tissue of pyloric mucosa. Additionally the gene expression of other extracellular matrix proteins, viz., collagen type III, fibronectin, osteopontin, proteoglycan NG2, laminin gamma1 and S-laminin, was also markedly increased, as determined by competitive RT-PCR after 14 days of MNNG exposure. The gene expression of osteonectin and the six other extracellular matrix proteins was elevated in twelve stomach adenocarcinomas and adenomas induced by MNNG in Lewis and WKY rats. Osteonectin-mAb-stained fibroblastic cells were evident in interstitial tissue of stomach tumor. These results suggest that osteonectin-expressing fibroblastic cells appear in the interstitial tissue of pyloric mucosa from the early initiation stage of rat stomach chemical carcinogenesis, and that this phenomenon probably plays a role in cancer development.

Dendritic cell appearance and differentiation during early and late stages of rat stomach carcinogenesis.

Dendritic cell appearance and differentiation during early and late stages of rat stomach carcinogenesis were studied in the pyloric mucosa. Young male rats were given drinking water with or without N-methyl-N'-nitro-N-nitrosoguanidine (MNNG; 100 mg/liter) for 14 days. Use of competitive RT-PCR and northern blotting showed that MNNG exposure induced 3- to 4-fold greater expression of the genes for integrin beta7 and integrin alphaE2 (identical with antigen OX-62, a dendritic cell marker), as well as three cytokines, IL-4, GM-CSF and TNFalpha, in the stomach pyloric mucosa of resistant Buffalo rats compared to sensitive ACI rats. These genes were minimally expressed in control animals. The results confirm the appearance of dendritic cells in the target pyloric mucosa and suggest the possibility that dendritic cell differentiation and maturation are induced by various cytokines, at least in Buffalo rats. Competitive RT-PCR showed expression of integrin alphaE2 and beta7, MHC class II-associated invariant chain (Ii), MHC class II, B7-1, CD28, GM-CSF and TNFalpha genes in all 12 examined stomach adenocarcinomas and adenomas induced in male Lewis and WKY rats with 30 weeks' MNNG exposure, suggesting the presence of dendritic cells in tumors. OX-62 staining and western blotting for OX-62 also confirmed the presence of dendritic cells in tumors. However, the population of dendritic cells in tumors was less than that in the pyloric mucosa after 14 days' MNNG exposure. The present results suggest that immune defense involving dendritic cells is marshaled from the very early initiation stage during rat stomach cancer development, but is downgraded in developed tumors.