Kinetic evaluation of nitrification performance in an immobilized cell membrane bioreactor.

High rate membrane bioreactor (MBR) systems operated at extremely low sludge ages (superfast membrane bioreactors (SFMBRs)) are inefficient to achieve nitrogen removal, due to insufficient retention time for nitrifiers. Moreover, frequent chemical cleaning is required due to high biomass flux. This study aims to satisfy the nitrification in SFMBRs by using sponge as carriers, leading to the extension of the residence time of microorganisms. In order to test the limits of nitrification, bioreactor was run under 52, 5 and 2 days of carrier residence time (CRT), with a hydraulic retention time of 6 h. Different degrees of nitrification were obtained for different CRTs. Sponge immobilized SFMBR operation with short CRT resulted in partial nitrification indicating selective dominancy of ammonia oxidizers. At higher CRT, simultaneous nitrification-denitrification was achieved when accompanying with oxygen limitation. Process kinetics was determined through evaluation of the results by a modeling study. Nitrifier partition in the reactor was also identified by model calibration.

Different surgical techniques and L-carnitine supplementation in an experimental varicocele model.

We aimed to investigate the impact of various varicocelectomy techniques and/or L-carnitine as an adjunct treatment, following the emergence of oxidative stress, on the expression levels of SCF/c-kit signalling pathways in spermatogenesis. Forty-two rats were divided into seven groups: group 1 (G1) control; group 2 (G2) sham; group 3 (G3) varicocele; group 4 (G4) varicocele + varicocelectomy with testicular nonartery sparing; group 5 (G5) same as G4 but with artery sparing; group 6 (G6) same as G4 but with L-carnitine and group 7 (G7) same as G5 with L-carnitine. mRNA expression levels of SCF and c-kit were measured quantitatively using real-time polymerase chain reaction. CASP-3 activity at protein level was determined, and histological evaluation was performed. mRNA expression level of SCF increased in G6 as compared to control group (3.52-folds change; P = 0.035), whereas mRNA expression level of c-kit gene remained the same. We found that in the left testis of G6 group, mRNA expression level of SCF increased 2.2-folds in comparison with the right testis (P < 0.05). There were no statistically significant differences in the CASP-3 protein expression levels between the control and other groups. When Cosentino Score analyses of immunostaining were conducted, we observed no significant differences among groups. Spermatogenic failure could be primarily due to a sertoli cell dysfunction. Although surgical treatment has been the best option for management of varicocele, auxiliary agents like L-carnitine may be considered as supportive treatment regimes in addition to conventional surgical treatments.

Impact of mixing on water quality in the Bosphorus - Implications on sustainable management of wastewater marine discharges.

The study established the water quality modelling of the Bosphorus system, based on hydrodynamic data as well as the results of the water quality survey carried out in the last five years. The model revealed significant decrease in the magnitude of pollutant loads in the upper layer at the exit into The Marmara Sea providing numerical proof that no pollutant transport would take place from sewage discharges to the upper layer. A similar modelling approach was implemented at the Bosphorus/Marmara interface, a significant hotspot as it included two major deep marine outfalls. The results asserted that the entire sewage flow would enter the lower flow in The Bosphorus through the interface without an appreciable mixing with the upper flow. This way, the study provided a significant scientific support for the sustainable management of marine discharges in this area, since they have no physical interference with The Marmara Sea.

Small bowel obstruction due to anomalous congenital peritoneal bands - case series in adults.

BACKGROUND: Congenital bands cause 3 % of all intestinal obstruction and almost always lead to small bowel obstruction. In adults, obstruction due to bands is even rarer. MATERIALS AND METHODS: A multicenter study in Turkey. From January 2000 to December 2010 inclusive - a period of 10 years - all adult patients admitted to the emergency departments with a clinical diagnosis of acute intestinal obstruction due to congenital peritoneal band were included in the study. Surgery was defined as emergency. Recorded operative findings included the site of obstruction, and the operative procedure to relieve it. In the present study, the findings in adult patients with congenital band reported in the literature together with findings in ten cases operated at four center were retrospectively assessed with respect to their demographic, preoperative, peroperative, and postoperative characteristics. RESULTS: There were 8 males and 2 females aged between 18 and 72 year. There were no history of abdominal or inguinal surgery. Plain abdominal X-rays radiography revealed air- fluid levels in all patients. All the bands were ligated and divided. On histopathological examination, the bands were composed of loose connective tissue containing blood vessels. There were no calcification in the bands. CONCLUSION: an anomalous congenital band could be included in the differential diagnosis of intestinal obstruction. This clinical situation requires early surgical intervention that will be diagnostic and therapeutic (Tab. 1, Fig. 4, Ref. 21).

Resection and primary anastomosis with modified blow-hole colostomy or Hartmann's procedure. Which method should be performed for gangrenous sigmoid volvulus?

AIM: To evaluate the efficacy of Hartmann's procedure and RPA with modified blow-hole colostomy for gangrenous sigmoid volvulus. METHODS: Sixty-one patients operated on between January 2004 to September 2010 were reviewed retrospectively. The demographic data of the patients,clinical features, type of surgical procedure performed, postoperative complications, mortality and duration of hospital stay (DHS) after surgery were reviewed. RESULTS: The mean hospital stay, wound infection and mortality did not differ significantly between the groups. Superficial wound infection rate was higher in group A (32% vs15%). Development of leaks secondary to stoma closure was not observed in any patient. During hospitalisation period; the postoperative complications were wound infection in four patients, intraabdominal abscess in two, evisceration and wound dehiscence in two, arrhythmia in six, pneumonia in eight.Medical and surgical complication rates of the groups were not different (p>0.05). When compared, the durations of intensive care unit (ICU) stay were not statistically different (p>0.05), but mean duration of hospital stay (DHS) was longer in group A than group B (p less than 0.05). CONCLUSION: Sigmoidectomy should be the basic principle in the management of sigmoid volvulus.RPA with modified blow - hole colostomy provides satisfactory results. It is easy to perform in patients with sigmoid volvulus. RPA with modified blow - hole colostomy can be performed safely in selected patients without increasing morbidity and DHS.

Pollutant dynamics between The Black Sea and The Marmara Sea: Basis for wastewater management strategy.

The study evaluated pollutant dynamics between The Black Sea and The Marmara Sea using data collected during a marine survey of the region around The Bosphorus strait, in the last five years. A hydraulic model was utilized to define two-layered water exchange in The Bosphorus. Analysis of pollutant exchange indicated The Black Sea as major polluter for the marine environment in The Marmara Sea. Four wastewater outfalls are located along The Bosphorus; Mass balances between the two ends of The Bosphorus indicated losses of 44 t/d total N and 138 t/d COD in the lower layer before reaching The Black Sea. This was explained with a simultaneous nitrification-denitrification process sustained in the low oxygen or anoxic zones around the outfalls, implying that a sustainable wastewater strategy should preclude additional treatment for The Bosphorus discharges, since they do not have an appreciable impact on the water quality of the lower flow.

DNA repair genes in endometriosis.

Several polymorphisms in the DNA repair gene are thought to have significant effects on cancer risk. We investigated the association of polymorphisms in the DNA repair genes XRCC1 Arg399Gln, XRCC3 Thr241Met, XPD Lys751Gln, XPG Asp1104His, APE1 Asp148Glu, and HOGG1 Ser326Cys with endometriosis risk. Genotypes were determined by PCR-RFLP assays in 52 patients with endometriosis and 101 age-matched healthy controls. Although there were no significant (P > 0.05) differences in the frequencies of genotypes or alleles of APE1, XRCC1, XPD, XPG, and HOGG1 genes between patients and controls, the frequency of the XRCC3 Thr/Thr genotype was significantly greater in endometriosis patients compared with controls (P = 0.005). XRCC3 Thr/Met genotypes (P = 0.022), and the Met allele (P = 0.005) seem to have a protective role against endometriosis. The distributions of genotypes and alleles of the genes APE1, XRCC1, XRCC3, XPD, XPG, and HOGG1 were not significantly associated with the different stages of endometriosis (P > 0.05). We conclude that the XRCC3 Thr/Thr genotype is associated with endometriosis in Turkish women.

CCR2-64I is a risk factor for development of bladder cancer.

Chemokines are potent proinflammatory cytokines that are implicated in numerous inflammatory diseases. Proinflammatory gene polymorphisms lead to variations in the production and concentration of inflammatory proteins. We investigated a possible association between polymorphisms in chemokine and chemokine receptor genes (MCP-1 A-2518G and CCR2-V64I) and bladder cancer risk. Genotypes were determined by PCR-RFLP assays in 72 bladder cancer patients and 76 unrelated age-matched healthy controls. There were significant differences in the frequencies of the MCP-1 A-2518G (P = 0.012) and CCR2-V64I genotypes (P = 0.004) between the controls and patients. The MCP-1 A-2518G GG genotype frequencies for controls and cases were 0.039 and 0.11, respectively; individuals who had the GG genotype had a 3-fold increased risk of bladder cancer (P = 0.08). The CCR2-64I/64I genotype frequencies for controls and cases were 0.02 and 0.13, respectively; subjects carrying the 64I/64I genotype had a 5.9-fold increased risk of bladder cancer compared to the other genotypes. Individuals carrying the CCR2-V64I heterozygote or homozygous variant genotype (64I/64I + wt/64I) had a 2.9-fold increased risk of bladder cancer compared with the wild-type genotype (wt/wt). CCR2-V64I heterozygote or homozygous wild-type genotype (wt/wt + wt/64I) frequencies were significantly decreased in the patient group compared with controls. We conclude that CCR2-64I is a new risk factor for bladder cancer.

Respirometric evaluation of biodegradation characteristics of dairy wastewater for organic carbon removal.

This study evaluates the biodegradation kinetics of an integrated dairy wastewater, with the main purpose of defining the experimental basis for modelling of the activated sludge process. Besides conventional characterization, the experiments involved detailed chemical oxygen demand (COD) fractionation and assessment of major kinetic and stoichiometric coefficients, by using respirometric methods. A multi-component model based on the endogenous decay concept was used for the kinetic interpretation. The results of conventional analyses and respirometric evaluations together with the assessment of residual components showed that the organic carbon content of the dairy wastewater was mostly soluble and biodegradable. The soluble, slowly biodegradable COD was the major COD fraction, representing around 50% of the total COD. Model calibration of the oxygen uptake rate profiles were consistent and revealed the existence of dual hydrolysis kinetics for soluble and particulate COD components. The hydrolysis rate associated with the main COD component--the soluble, slowly biodegradable COD fraction--was found to be 1.2 d(-1), which is quite low and underlines the role of this COD fraction as the rate-limiting factor for effluent quality. Simulation of process efficiency by the adopted model, calibrated with the experimentally determined parameters, indicated that effective control of the biodegradation of the soluble biodegradable COD components could be done by selection of appropriate values for the sludge age and hydraulic retention time. In this way, the total effluent soluble COD level could be lowered to 30-40 mg L(-1) range, in conformity with effluent limitations.

Transcriptomic expression levels of the VHL, TIMP-3, and RASSF1A genes in renal tumors.

OBJECTIVE: In this study, we aimed to investigate the relation between the mRNA expression levels of VHL, TIMP-3 and RASSF1A genes, and the histopathological and clinical characteristics of patients with renal tumors. PATIENTS AND METHODS: Radical nephrectomy specimens of cases presented without neoadjuvant treatment were confirmed to be cancerous, non-cancerous, benign, and healthy after removal from separate localizations. A total of 69 patients with kidney tumors (138 tissue samples) were included in the study group. RNA isolation, reverse transcriptase PCR (RT-PCR), and quantitative real time PCR (qPCR) were performed, and the GAPDH gene was used to normalize mRNA levels. RESULTS: In the RCC cancerous tissue, TIMP-3 levels increased 1.3 times and RASSF1A levels increased 1.4 times compared to the corresponding levels in non-cancerous tissues, and there was no statistically significant difference in these values. On the other hand, VHL gene expression levels in cancerous tissue were 2.8 times higher than in matched adjacent non-cancerous tissues (p < 0.05). In the case of oncocytomas, TIMP-3 levels were found to be 3.2 times higher, RASSF1A levels 3.8 times higher, and VHL levels 2.2 times lower than the corresponding levels in healthy tissues (p < 0.05). CONCLUSIONS: The roles of VHL, TIMP-3, and RASSF1A mRNA expression in contributing to the development of renal tumors could not be clearly established. Further studies are therefore required to elucidate the mechanisms underlying renal tumors.

False positive 18F-FDG PET scan in adrenal oncocytoma.

18F-FDG whole-body positron emulsion tomography (18F-FDG PET) has become an established imaging modality for a variety of cancers. Today, 18F-FDG PET is utilized to differentiate benign from malignant non-functioning adrenal masses. In this report, a 25-year-old woman presented with a 2-month history of left flank pain. Abdominal CT revealed a left 6.5 x 4.5 cm adrenal mass with regular margins and focal calcification. To make a differential diagnosis, 18F-FDG PET was performed. Preoperative laboratory studies showed that the mass was non-functioning. A left adrenalectomy was performed through a left subcostal incision. The final pathologic evaluation revealed adrenal oncocytoma. We present the disassociation between preoperative 18F-FDG PET and pathologic findings of a benign adrenocortical oncocytoma.

High temperature pyrolysis of sewage sludge as a sustainable process for energy recovery.

This study explored the potential of high temperature pyrolysis for energy recovery from domestic sewage. It mainly defines optimum operating conditions to maximize syngas generation. A pyrolysis unit was operated in batch mode, at temperatures of 450, 600 and 850 °C, rotation speeds of 10, 40 and 60 Hz. The sludge had 6% moisture content; it contained 65% organic matter and involved a low calorific value of 13.535 kJ/kg dry matter. Pyrolysis at 850 °C and high rotation speed of 60 Hz yielded the highest conversion of sludge to syngas, with an average of 59% of the organic matter as syngas, 29% as tar and 12% as biochar. Pyrolysis enabled 74% of the energy recovery as syngas and tar. Continuous full-scale pyrolysis systems would further increase the syngas by recovering condensable gaseous products and/or recycling tar back into the pyrolysis unit. A unified approach for energy recovery management should equally consider what fraction of the energy contained in the wastewater was consumed and wasted before generating the sludge. Therefore, the adopted management scheme should also cover all design and operation parameters of the treatment plant, because this is how the energy is best conserved even before the sludge is generated.

Toward a novel membrane process for organic carbon removal-fate of slowly biodegradable substrate in super fast membrane bioreactor.

The study tested the performance of super fast membrane bioreactor (SFMBR) using starch as a slowly biodegradable substrate, exploring the fate of starch, and the response of the microbial community. SFMBR was operated at extremely low sludge ages of 0.5-2.0 days, with a hydraulic retention time of 1.0 h. Average values for permeate chemical oxygen demand (COD) always remained in the narrow range between 14 and 18 mg/L, regardless of the selected mode of MBR operation at different sludge ages. Soluble COD levels in the reactor were consistently higher than the corresponding permeate COD. Parameters defining process kinetics, determined by model calibration of oxygen uptake rate (OUR) profiles, varied as a function of sludge age. Model simulation of SFMBR performance indicated total removal of hydrolysis products so that permeate COD consisted of residual microbial products. PCR-DGGE experiments revealed significant shifts in the composition of the microbial community imposed by variations in the sludge age, reflecting on corresponding process kinetics.

Comparison of colorectal neoplastic polyps and adenocarcinoma with regard to NLR and PLR.

OBJECTIVE: Cancer-related inflammation affects many aspects of malignancy, including proliferation and survival of malignant cells, angiogenesis, and therapeutic response. Some biomarkers representing the degree of systemic inflammation, such as the Glasgow prognostic score, NLR and PLR, have been shown to have prognostic value in many kinds of cancer patients. Aim of this study to investigate to compare neutrophil/leukocyte (NLR) and platelet/lymphocyte (PLR) ratios of the patients with colorectal neoplastic polyps and colorectal cancer (CRC) and tried to determine whether this could be used as a biomarker in follow up of the patients with neoplastic polyps. PATIENTS AND METHODS: A total of 100 colorectal polyps, 113 colorectal cancers and 124 healthy controls were included in the study. Exculusion criteria were endocrinologic or metabolic diseases, acute or chronic diseases, hypertension and atherosclerotic heart diseases, renal diseases. Blood count parameters of the patients were measured. The NLR was calculated as a simple ratio between the absolute neutrophil and the absolute lymphocyte counts. The PLR was defined as the platelet counts to lymphocyte ratio. RESULTS: A statistically significant difference was not detected between Group A and C with regard to NLR and PLR. NLR and PLR were found statistically significantly high in Group B (CRC), Group A (colorectal polyp) and Group C (healthy individuals) (p < 0.001 and p < 0.001). Our study showed that the optimum NLR cut-off point for neoplastic polyps was 2.28 (sensitivity: 68.7%, specificity: 42.3%). When the sensitivity and specificity levels of the PLR were assessed, they were 68.7% and 46.5% for neoplastic polyps, 80% and 68.9% for colorectal cancer. CONCLUSIONS: NLR and PLR may be used for follow up conversion of colonic and rectal neoplastic polyps to invasive tumor.

Glutathione S-transferase M1 gene polymorphism in bladder cancer patients. a marker for invasive bladder cancer?

The glutathione S-transferase M1 (GSTM1) gene is polymorphic in humans, and the deficiency in enzyme activity of GSTM1 is caused by the inherited homozygous absence of the GSTM1 gene, or the "null" genotype (GSTM1, 0/0). The increased risk of bladder cancer has been shown to correspond with this gene defect. No reports, however, have been found in the literature regarding GSTM1 gene deficiency with superficial and invasive bladder cancer. In this study, we examined the association of the GSTM1-null genotype with superficial and invasive bladder cancer. Using a polymerase chain reaction (PCR)-based method, we examined the frequency of the GSTM1 gene defect in Turkish patients with superficial bladder cancer (N = 61), invasive bladder cancer (N = 42), and control subjects (N = 202) who had no history of cancer. The GSTM1 null genotype was observed in 34.7% of the control subjects and in 54.3% of total bladder cancer patients (OR: 2.246; 95% CI: 1.384-3.645, P: 0.00094). In other words, the presence of the GSTM1-null genotype significantly increased the risk of bladder cancer development. Among invasive bladder cancers, the frequency of the GSTM1-null genotype was 64.3% (OR: 0.294, 95% CI: 0.147-0.590, P: 0.0003). This was also significantly higher than control subjects, indicating that patients carrying this genotype were at increased risk for developing invasive bladder cancer. This relationship was not statistically significant in the superficial bladder cancer group (OR: 0.585, 95% CI: 0.327-1.045, P: 0.06). Our results indicate that GSTM1 gene polymorphism should be considered as an important risk modifier in the development of bladder cancer and might be used as a predictive marker for invasive bladder cancer.

Combined use of prostate-specific antigen derivatives decreases the number of unnecessary biopsies to detect prostate cancer.

The authors evaluated the prostate cancer detection rate in Turkish patients with prostate-specific antigen (PSA) levels of 4 ng/ml to 10 ng/ml and who had normal digital rectal examination (DRE) findings. They also aimed to evaluate the value of PSA density and percent free PSA in minimizing unnecessary prostate biopsies for these PSA ranges. This prospective study included 134 consecutive men referred for early prostate cancer detection or lower urinary tract symptoms. All men underwent transrectal ultrasound with systematic sextant needle biopsies. The ability of PSA density and percent free PSA to improve the power of PSA in the detection of prostate cancer was evaluated with statistical analyses as well as receiver operating characteristics curves. Among the 134 men, 124 (92.5%) had a benign histology and 10 (7.5%) had cancer diagnosed on the initial biopsies. Despite the disappointing results in regard to the sensitivity and specificity of PSA derivatives alone, the combination of PSA density and percent free PSA significantly increased the area under the curve compared with the use of each test alone. To increase the specificity of PSA in this patient population, the authors recommend combining two PSA derivatives in deciding whether to perform a biopsy. In a PSA range of 4 ng/ml to 10 ng/ml and with normal DRE, a percent free PSA < 21% and a PSA density > 0.18 yields highest specificity with 90% sensitivity.

Combination of pneumatic lithotripsy and transurethral prostatectomy in bladder stones with benign prostatic hyperplasia.

We present our experience with combined pneumatic lithotripsy and transurethral resection of the prostate (TURP) in 52 patients with bladder stone(s) and benign prostatic hyperplasia (BPH). All stones were fragmented with the pneumatic Swiss Lithoclast. Pneumatic lithotripsy and evacuation caused a mean increase of 16 minutes in operating time. No complications, other than mild hematuria, were observed intraoperatively because of pneumatic lithotripsy. We observed early and long-term complications related to the procedure in 13% of patients. The average hospital stay was 3.2 days. The combination of pneumatic lithotripsy and TURP appears to be an effective, safe, and economical treatment method for patients with bladder stone(s) and BPH.

Serum levels of interleukin-18 and nitrite+nitrate in renal cell carcinoma patients with different tumor stage and grade.

Interleukin (IL-18) and nitric oxide (NO) are immunoregulatory cytokines that have been suggested to participitate in the multistep process of carcinogenesis. In this study, serum IL-18 and nitrite+nitrate levels (as an index of NO generation) were measured in 26 patients with histologically confirmed renal cell carcinoma (RCC) before surgical procedure and in 8 healthy controls. RCC patients showed significantly higher serum IL-18 levels when compared to the control subjects (p<0.001). Serum IL-18 levels were found to be similar in patients with T1 and T2, T3, T4 tumors (p>0.05). Patients with grade 3 and 4 tumors showed significantly higher serum IL-18 levels when compared to the patients with grade 1 and 2 tumors (p<0.05). No significant difference was found in serum nitrite+nitrate levels between RCC patients and control subjects (p>0.05). Serum nitrite+nitrate levels were lower in patients with grade 3 and 4 tumors than those with grade 1 and 2 tumors, but this was not statistically significant (p=0.063). In conclusion, elevated serum level of IL-18 in RCC patients than in controls and extra-increase of this level in those with high grade tumors may reflect the degree of human defence mechanisms against tumor cells in RCC.

Characterization and COD fractionation of domestic wastewaters.

Results of a comprehensive study are reported for wastewater characterization in relation to modelling and design of biological nutrient removal systems for the Metropolitan Area of Istanbul. Domestic sewage quality was experimentally assessed in terms of major polluting parameters. Size distribution and calculation of significant ratios such as BOD5:COD and COD:N were used to evaluate the merit of candidate physical, chemical and biological treatment alternatives. COD fractionation was effected to assess biological treatability and to yield the necessary process components to the recent modelling approaches.

Antibiotic prophylaxis for transrectal biopsy of the prostate: a prospective randomized study of the prophylactic use of single dose oral fluoroquinolone versus trimethoprim-sulfamethoxazole.

We investigated the efficacy of prophylactic use of single dose oral ofloxacin and trimethoprim-sulfamethoxazole regimens for transrectal prostate biopsy in 110 men. In the ofloxacin, trimethoprim-sulfamethoxazole and control groups, urinary infection was found in 2 (4.76%), 3 (6.66%) and 6 (26.08%) patients, respectively. Both of these antibiotic regimens produced a statistically significant reduction in urinary infection (p<0.02, p<0.05). Our study indicates that single dose fluoroquinolone or trimethoprim-sulfamethoxazole prophylaxis seems to be effective, practical and economical.