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.

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.

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.

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.

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.

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.

Scientific basis of dissolved organic carbon limitation for landfilling of municipal treatment sludge--is it attainable and justifiable?

This study evaluated the scientific and technical basis of the dissolved organic carbon (DOC) limitation imposed on municipal sludge for landfilling, mainly for assessing the attainability of the implemented numerical level. For this purpose, related conceptual framework was analyzed, covering related sewage characteristics, soluble microbial products generation, and substrate solubilization and leakage due to hydrolysis. Soluble COD footprint was experimentally established for a selected treatment plant, including all the key steps in the sequence of wastewater treatment and sludge handling. Observed results were compared with reported DOCs in other treatment configurations. None of the leakage tests performed or considered in the study could even come close to the prescribed limitation. All observed results reflected 10-20 fold higher DOC levels than the numerical limit of 800 mg/kg (80 mg/L), providing conclusive evidence that the DOC limitation imposed on municipal treatment sludge for landfilling is not attainable, and therefore not justifiable on the basis of currently available technology.

Effect of high loading on substrate utilization kinetics and microbial community structure in super fast submerged membrane bioreactor.

The study investigated the effect of high substrate loading on substrate utilization kinetics, and changes inflicted on the composition of the microbial community in a superfast submerged membrane bioreactor. Submerged MBR was sequentially fed with a substrate mixture and acetate; its performance was monitored at steady-state, at extremely low sludge age values of 2.0, 1.0 and 0.5d, all adjusted to a single hydraulic retention time of 8.0 h. Each MBR run was repeated when substrate feeding was increased from 200 mg COD/L to 1000 mg COD/L. Substrate utilization kinetics was altered to significantly lower levels when the MBR was adjusted to higher substrate loadings. Molecular analysis of the biomass revealed that variable process kinetics could be correlated with parallel changes in the composition of the microbial community, mainly by a replacement mechanism, where newer species, better adapted to the new growth conditions, substituted others that are washed out from the system.

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.

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.

The effects of glutamine on hepatic ischemia reperfusion injury in rats.

AIM: To evaluate the effects of glutamine on the hepatic ischemia reperfusion injury in rats. METHODS: Thirty rats were divided into three groups as sham (Group 1), control (Group 2), and glutamine(gln) treatment group (Group 3). All rats underwent hepatic ischemia for 45 min followed by 60 min period of reperfusion. Rats were intraperitoneally infused with only 0.9% saline solution in group 2. Rats in group 3 received gln (0.75 g/kg) by intraperitoneal administration, before ischemia and before reperfusion. Blood samples and liver tissues were harvested from the rats, and then the rats were sacrificed. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) levels were determined. Total antioxidant capacity (TAC), catalase (CAT), total oxidative status (TOS), oxidative stress index (OSI) and myeloperoxidase (MPO) in hepatic tissue were measured. Also liver tissue histopathology was evaluated by light microscopy. RESULTS: The levels of liver enzymes in group 3 were significantly lower than those in the group 2. TAC in liver tissue was significantly higher in group 3 than in group 2. TOS, OSI and MPO in hepatic tissue were significantly lower in group 3 than the group 2. Histological tissue damage was milder in the gln treatment group than that in the control group. CONCLUSION: Our results suggest that gln treatment protects the rat liver against to hepatic ischemia-reperfusion injury.

The use of fibrin sealant after total thyroidectomy for benign disease obviates the need for routine drainage. Results of a randomized controlled trial.

BACKGROUND: Drains are usually left after thyroid surgery to prevent formation of hematoma and seroma in the thyroid bed. This prospective randomized clinical trial was conducted to evaluate the necessity of drainage after total thyroidectomy for benign thyroidal disorders. METHODS: The patients were assigned randomly into two groups (group 1: with suction drain, group 2: fibrin glue). In the study, operating time, postoperative pain, the total amount of intramuscular analgesic administration, hospital stay, complications (such as wound infection, seroma, bleeding, hematoma, recurrent laryngeal nerve palsy or hypoparathyroidism), were recorded. RESULTS: The drained group (group 1) consisted of 2 men and 48 women with a mean age of 47.76±11.22 years. The nondrained (plus fibrin sealant)( group 2) (comprised of 10 men and 40 women with a mean age of 44.72±11.32 years. There was no significant difference in the gender, age, hormonal status and histopathological results of the patients between the two groups (P=0.18, P=0.36, P=0.28 and P=0.40, respectively). The operations performed were total thyroidectomy in all patients. Twenty-five patients (50%) in the non-drained group did not need intramuscular analgesic, whereas 15 patients (30%) did not in the drained group (P=0.01). In addition, the mean amount of intramuscular analgesic requirement was significantly less in the non-drained group than in the drained group (P=0.02). The complication rates were similar between the two groups. One case of hematoma (2%), two cases of seroma (4%) and three cases of transient hypoparathyroidism (6%) occurred in the non-drained group, whereas one case of hematoma (2%), two cases of seroma (4%), two cases of wound infections (4%) and two cases of transient hypoparathyroidism (4%) occurred in the drained group (P=0.69). No patient needed surgical revision or re-operation for any complication and all complications were successfully managed conservatively. CONCLUSION: Routine drainage of thyroid bed following thyroid surgery may not be necessary. Not draining the wound results in lesser morbidity and decreased hospital stay.

Are postoperative drains necessary with the Karydakis flap for treatment of pilonidal sinus? (Can fibrin glue be replaced to drains?) A prospective randomized trial.

PURPOSE: Different surgical techniques for pilonidal disease have been described in the literature. In this study, our aim was to evaluate the influence of routine cavity drainage in the Karydakis flap technique. METHODS: As much as 50 male patients with pilonidal sinus who underwent the Karydakis flap operation were evaluated prospectively.The patients were assigned randomly into two groups (Group 1 with suction drain; Group 2 fibrin glue). RESULTS: Fluid collection was encountered in 8 out of 50 patients (6.25%): 6 in Group 2 (24%) of which 4 experienced superficial, healed with simple dressing, the other 2 with substantial dehiscence healed with wound dressing; 2 in Group 1 (8%) were treated with wound punctures.There has been no recurrence in any of the patients during the follow-up period.The Karydakis flap operations can be performed with a near zero recurrence rate with the use of drains. CONCLUSION: We recommend the use of fibrin sealant with Karydakis flap procedure, but further studies are needed to confirm this conclusion.

The results of surgical treatment for hepatic hydatid disease.

BACKGROUND: Hydatid disease is an important health problem worldwide and surgery remains the gold standard in terms of treatment for patients with echinococcosis of the liver. In this study we aimed to present our recent surgical experience in treating patients with hepatic hydatidosis. PATIENTS AND METHODS: Fourty-eight patients with Liver Echinococcosis (LE) who were operated in our department between 2007 and 2008 were reviewed retrospectively. It was observed that cystectomy or hepatectomy had been preferred in certain patients with cysts of small size or subcapsular location. RESULTS: There was no significant difference in the type of surgical procedures and early post-operative complications. Recurrence rates and mean duration of hospitalization were significantly lower in patients treated by radical procedures than the patients in drainage and obliteration group. CONCLUSION: Radical operations for hydatid cyst disease are safe methods and may be preffered in selected cases.

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.

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.

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.

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.