Comparing methanol and glycerol as carbon sources for mainstream partial denitrification/anammox in an IFAS process.

This study explored the implementation of mainstream partial denitrification with anammox (PdNA) in the second anoxic zone of a wastewater treatment process in an integrated fixed film activated sludge (IFAS) configuration. A pilot study was conducted to compare the use of methanol and glycerol as external carbon sources for an IFAS PdNA startup, with a goal to optimize nitrogen removal while minimizing carbon usage. The study also investigated the establishment of anammox bacteria on virgin carriers in IFAS reactors without the use of seeding, and it is the first IFAS PdNA startup to use methanol as an external carbon source. The establishment of anammox bacteria was confirmed in both reactors 102 days after startup. Although the glycerol-fed reactor achieved a higher steady-state maximum ammonia removal rate because of anammox bacteria (1.6 ± 0.3 g/m2/day) in comparison with the methanol-fed reactor (1.2 ± 0.2 g/m2/day), both the glycerol- and methanol-fed reactors achieved similar average in situ ammonia removal rates of 0.39 ± 0.2 g/m2/day and 0.40 ± 0.2 g/m2/day, respectively. Additionally, when the upstream ammonia versus NOx (AvN) control system maintained an ideal ratio of 0.40-0.50 g/g, the methanol-fed reactor attained a lower average effluent TIN concentration (3.50 ± 1.2 mg/L) than the glycerol-fed reactor (4.43 ± 1.6 mg/L), which was prone to elevated nitrite concentrations in the effluent. Overall, this research highlights the potential for PdNA in IFAS configurations as an efficient and cost-saving method for wastewater treatment, with methanol as a viable carbon source for the establishment of anammox bacteria. PRACTITIONER POINTS: Methanol is an effective external carbon source for an anammox startup that avoids the need for costly alternative carbon sources. The methanol-fed reactor demonstrated higher TIN removal compared with the glycerol-fed reactor because of less overproduction of nitrite. Anammox bacteria was established in an IFAS reactor without seeding and used internally stored carbon to reduce external carbon addition. Controlling the influent ammonia versus NOx (AvN) ratio between 0.40 and 0.50 g/g allowed for low and stable TIN effluent conditions.

Probiotic Formulations Containing Fixed and Essential Oils Ameliorates SIBO-Induced Gut Dysbiosis in Rats.

Dysbiosis of the gut microbiota is associated with the pathogenesis of intestinal diseases such as inflammatory bowel disease, irritable bowel syndrome (IBS), small intestinal bacterial overgrowth (SIBO), and metabolic disease states such as allergies, cardiovascular diseases, obesity, and diabetes. SIBO is a condition characterized by an increased number (>1 × 103 CFU) of abnormal bacterial species in the small intestine. Interest in SIBO has gained importance due to increased awareness of the human microbiome and its potential relationships with human health and disease, which has encouraged new work in this area. In recent years, standard antibiotic regimens (rifaximin and metronidazole) have been used to treat SIBO, but solo antibiotics or their derivatives are insufficient. In this study, the therapeutic effects of the probiotic form, which contains coconut oil and traces of peppermint-lemon-patchouli essential oil, were evaluated on the Dysbiosis-Based Rat SIBO Model. There are significant differences between sick and healthy rats (p = 0.014), between sick rats and rats treated with the oil mix plus probiotic mix protocol (p = 0.026), and between rats treated with only the probiotic and only oil protocols (p = 0.030) in the evaluation of TNF-α levels. Histologically, villi distortion and loss of crypts, epithelial shedding and necrotic changes in the apical regions of the villi, and inflammatory cell infiltrations extending to the lamina propria and submucosa were observed in sick rats. Mitotic figures in villus epithelium and crypts were observed in rats treated with 9.2 × 109 CFU/1000 mg/coconut oil + trace amounts of peppermint-lemon-patchouli essential oil and a probiotic mixture (oil + probiotic mix protocol). A regression of inflammatory reactions and an increase in goblet cells were observed. A decrease was observed in inflammation markers in sick rats. On the other hand, the oil plus probiotic mix protocol recovered digestive system defects in the animals caused by dysbiosis. In the future, these treatment approaches can be effective in the treatment of SIBO.

Comparative assessment of energy generation from ammonia oxidation by different functional bacterial communities.

Bioelectrochemical ammonia oxidation (BEAO) in a microbial fuel cell (MFC) is a recently discovered process that has the potential to reduce energy consumption in wastewater treatment. However, level of energy and limiting factors of this process in different microbial groups are not fully understood. This study comparatively investigated the BEAO in wastewater treatment by MFCs enriched with different functional groups of bacteria (confirmed by 16S rRNA gene sequencing): electroactive bacteria (EAB), ammonia oxidizing bacteria (AOB), and anammox bacteria (AnAOB). Ammonia oxidation rates of 0.066, 0.083 and 0.082 g NH4+-N L-1 d-1 were achieved by biofilms enriched with EAB, AOB, and AnAOB, respectively. With influent 444 ± 65 mg NH4+-N d-1, nitrite accumulation between 84 and 105 mg N d-1 was observed independently of the biofilm type. The AnAOB-enriched biofilm released electrons at higher potential energy levels (anode potential of 0.253 V vs. SHE) but had high internal resistance (Rint) of 299 Ω, which limits its power density (0.2 W m-3). For AnAOB enriched biofilm, accumulation of nitrite was a limiting factor for power output by allowing conventional anammox activity without current generation. AOB enriched biofilm had Rint of 18 ± 1 Ω and yielded power density of up to 1.4 W m-3. The activity of the AOB-enriched biofilm was not dependent on the accumulation of dissolved oxygen and achieved 1.5 fold higher coulombic efficiency when sulfate was not available. The EAB-enriched biofilm adapted to oxidize ammonia without organic carbon, with Rint of 19 ± 1 Ω and achieved the highest power density of 11 W m-3. Based on lab-scale experiments (scaling-up factors not considered) energy savings of up to 7 % (AnAOB), 44 % (AOB) and 475 % (EAB) (positive energy balance), compared to conventional nitrification, are projected from the applications of BEAO in wastewater treatment plants.

Impact of Inoculum Type on the Microbial Community and Power Performance of Urine-Fed Microbial Fuel Cells.

Bacteria are the driving force of the microbial fuel cell (MFC) technology, which benefits from their natural ability to degrade organic matter and generate electricity. The development of an efficient anodic biofilm has a significant impact on the power performance of this technology so it is essential to understand the effects of the inoculum nature on the anodic bacterial diversity and establish its relationship with the power performance of the system. Thus, this work aims at analysing the impact of 3 different types of inoculum: (i) stored urine, (ii) sludge and (iii) effluent from a working MFC, on the microbial community of the anodic biofilm and therefore on the power performance of urine-fed ceramic MFCs. The results showed that MFCs inoculated with sludge outperformed the rest and reached a maximum power output of 40.38 mW·m-2anode (1.21 mW). The power performance of these systems increased over time whereas the power output by MFCs inoculated either with stored urine or effluent decreased after day 30. These results are directly related to the establishment and adaptation of the microbial community on the anode during the assay. Results showed the direct relationship between the bacterial community composition, originating from the different inocula, and power generation within the MFCs.

A case report of a unique aorto-bifemoral graft infection and its treatment.

In this study, we report a unique case of aorto-bifemoral graft infection, which developed in a 47-year-old male patient after endovascular aortic aneurysmal repair (EVAR) and extra anatomic axillo-femoral bypass. The patient had previously been treated by EVAR for an infrarenal abdominal aortic aneurysm. Earlier, the EVAR was blocked by a thrombosis and treated with an extra-anatomic axillo femoral bypass, which then became occluded. The patient was then treated with an aorto-bifemoral bypass using a Dacron Y graft. A few months later, he was referred to our cardiovascular center with high body temperature, weight loss, inability to stand and walk, and very serious sepsis. A computed abdominal tomography scan revealed that a part of the graft proximal to the bifurcation had totally eroded into the proximal jejunum. We treated this patient with multiple surgeries, antibiotic administrations and hypochlorous acid irrigation without graft excision, which carries a high morbidity and mortality risks.

Resilience and limitations of MFC anodic community when exposed to antibacterial agents.

This study evaluates the fate of certain bactericidal agents introduced into microbial fuel cell (MFC) cascades and the response of the microbial community. We tested the response of functioning urine fed MFC cascades using two very different bactericidal agents: a common antibiotic (Ampicillin, 5 g/L) and a disinfectant (Chloroxylenol 4.8 g/L) in concentrations of up to 100 times higher than the usual dose. Results of power generation showed that the established bacteria community was able to withstand high concentrations of ampicillin with good recovery after 24 h of minor decline. However, power generation was adversely affected by the introduction of chloroxylenol, resulting in a 99% loss of power generation. Ampicillin was completely degraded within the MFC cascade (>99.99%), while chloroxylenol remained largely unaffected. Analysis of the microbial community before the addition of the bactericidal agents showed a significant bacterial diversity with at least 35 genera detected within the cascade. Microbial community analysis after ampicillin treatment showed the loss of a small number of bacterial communities and proportional fluctuations of specific strains within the individual MFCs community. On the other hand, there was a significant shift in the bacterial community after chloroxylenol treatment coupled with the loss of at least 13 bacterial genera across the cascade.

Development of efficient electroactive biofilm in urine-fed microbial fuel cell cascades for bioelectricity generation.

The Microbial fuel cell (MFC) technology harnesses the potential of some naturally occurring bacteria for electricity generation. Digested sludge is commonly used as the inoculum to initiate the process. There are, however, health hazards and practical issues associated with the use of digested sludge depending on its origin as well as the location for system deployment. This work reports the development of an efficient electroactive bacterial community within ceramic-based MFCs fed with human urine in the absence of sludge inoculum. The results show the development of a uniform bacterial community with power output levels equal to or higher than those generated from MFCs inoculated with sludge. In this case, the power generation begins within 2 days of the experimental set-up, compared to about 5 days in some sludge-inoculated MFCs, thus significantly reducing the start-up time. The metagenomics analysis of the successfully formed electroactive biofilm (EAB) shows significant shifts between the microbial ecology of the feeding material (fresh urine) and the developed anodic biofilm. A total of 21 bacteria genera were detected in the urine feedstock whilst up to 35 different genera were recorded in the developed biofilm. Members of Pseudomonas (18%) and Anaerolineaceae (17%) dominate the bacterial community of the fresh urine feed while members of Burkholderiaceae (up to 50%) and Tissierella (up to 29%) dominate the anodic EAB. These results highlight a significant shift in the bacterial community of the feedstock towards a selection and adaptation required for the various electrochemical reactions essential for survival through power generation.

Overcoming challenges in mainstream Anammox applications: Utilization of nanoscale zero valent iron (nZVI).

Although Anammox process is a proven technology for sidestream nitrogen removal, the process faces challenges for mainstream applications in sewage treatment plants (STPs). The aim of this study was to investigate the effect of zero valent iron nanoparticles (nZVI) on process performance to eliminate confronts for mainstream applications. An SBR (sequencing batch reactor) system was fed with various nZVI concentrations (0.04-5000 ppb) within 310 days of operation. Ammonium (NH4+-N) and nitrite (NO2--N) removal rates showed 58% increase in daily measurements and 73% increase in instant measurements. Specific Anammox Activity (SAA) was noticeably higher on the days the system was exposed to nZVI compared to the unexposed days. EPS secretion, which enhances granulation of Anammox bacteria was favored by nZVI. Despite lower sludge retention time (SRT) values, the fraction of Anammox bacteria in total bacteria reached to 91-92% implying a boosting effect of nZVI on growth rate of Anammox bacteria. High Resolution Melting (HRM) analyses showed that four distinct clades were present in the reactor.

Anammox start-up strategies: the use of local mixed activated sludge seed versus Anammox seed.

The start-up period of Anammox systems is still a big challenge due to the unavailability of large volumes of slowly growing Anammox seed locally in most countries. This study aims to evaluate the effects of seeding strategy on the start-up and enrichment period of Anammox systems by monitoring both process performance and microbial population dynamics. Two different seeding strategies, the use of mixed activated sludge culture from a local STP and the use of enriched Anammox culture transported from abroad, were comparatively studied in SBR systems operated for 410 days. The enriched Anammox seed from abroad inhibited seriously during transportation. Anammox activity re-started after 195 days' recovery period. An active Anammox culture was successfully enriched within 95 days from a local activated sludge source without seeding any Anammox. The Anammox population reached levels of 1011 copies/ng at the end of 410 days' enrichment period. Based on FISH, Ca. Brocadia anammoxidans and Ca. Scalindua species were dominant in the enriched culture. The maximum TNRR was observed as 430 mg N/day. DGGE analyses revealed a drastic change in the microbial community (56%) with Anammox enrichment. Phylogenetic analysis demonstrated a significant decrease in phylotype Proteobacteria and increase in phylotypes Planctomycetes, Chloroflexi and Acidobacteria with enrichment.

Risk factors for infection development after transrectal prostate biopsy and the role of resistant bacteria in colonic flora.

INTRODUCTION: In this study, we aimed to identify risk factors for the development of infectious complications after prostate biopsy and to investigate the role of intestinal colonization of bacteria that are resistant to prophylactic antibiotics. METHODOLOGY: A total of 168 patients who had undergone transrectal prostate biopsy (TRPB) under ciprofloxacin and gentamycin prophylaxis were included in the study. Stool cultures and subsequent antibiotic susceptibility testing were performed in all patients before the start of antibiotic prophylaxis. RESULTS: Of the 168 patients, 17 (10.1%) developed urinary tract infection (UTI), while 6 (3.57%) developed sepsis within seven days after biopsy. Ciprofloxacin-resistant bacterial colonization was detected in 81 (48.2%) of the patients. None of the patients with ciprofloxacin-sensitive bacteria in intestinal flora developed a UTI. The colonization of intestinal ciprofloxacin-resistant bacteria increased UTI risk significantly after TRPB (p < 0.0001). Urolithiasis history, presence of permanent urinary catheterization, hospitalization history for more than 48 hours in the last year, and recent antibiotic usage significantly increased UTI risk after TRPB. CONCLUSIONS: Development of an infection was more frequent in patients with resistant bacterial colonization. We hope to guide more comprehensive studies designed to find a standard prophylactic regimen for TRPB that can be used all over the world.

An Unusual Manifestation of Q Fever: Peritonitis.

Q fever has rarely been reported and can be difficult to diagnose, especially in immunocompromised patients. In the present report, we describe an unusual case of Q fever that presented as peritonitis and was treated with long-term combination therapy with doxycycline, ciprofloxacin and rifampicin for five weeks in a patient who had been on peritoneal dialysis for six years due to hypertensive nephropathy.

National practice in antibiotic prophylaxis in breast cancer surgery.

BACKGROUND: Although breast cancer surgery is regarded as a "clean" surgery, surgical site infection (SSI) rates are higher than expected. There is no consensus regarding the use of antibiotic prophylaxis in elective breast surgery. The nationwide survey was conducted to determine the trend of antibiotic prophylaxis in breast cancer among Turkish surgeons. METHODS: The survey was sent to surgeons who are member of Turkish Surgical Association (TSA) via e-mail from TSA web address. A 15 item web-based survey consisted of surgeon demographics and the use of prophylactic antibiotic in patients with risk factors related to SSI. RESULTS: The number of completed questionnaires was 245. The most common antibiotic used was first generation of cephalosporins. A majority of respondents indicated that prophylaxis was preferred in patients with high risk of SSI including preoperative chemotherapy or radiotherapy, older age, diabetes mellitus, immunodeficiency, immediate reconstruction (P < 0.05). However, the use of drain did not significantly influence antibiotic prophylaxis (P = 0.091). CONCLUSIONS: The use of prophylactic antibiotic was strongly dependent on the presence of some risk factors; however, the variation in current practice regarding antibiotic prophylaxis demonstrated a lack of its effect on preventing SSI after breast cancer surgery.

Case management and supportive treatment for patients with Crimean-Congo hemorrhagic fever.

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne infection which has been increasing in Turkey and European countries since the year 2000. The disease is particularly endemic in the Middle East and in some African countries. It is also seen in European countries as a travel infection. Patients with confirmed diagnosis are usually hospitalized for monitoring, while patients with good overall condition may be monitored on an outpatient basis. Hospitals that manage CCHF should have easy access to a blood bank, and tertiary care hospitals must have a well-equipped intensive care unit. Strict blood and body fluid control precautions should be started on admission to limit CCHF exposure. The follow-up period for each patient is determined based on individual clinical status and laboratory values. Since there is no specific antiviral treatment for CCHF, supportive treatment is essential. This review highlights some of the major features of case monitoring and supportive treatment in CCHF.

Comparative activity of carbapenem testing (the COMPACT study) in Turkey.

BACKGROUND: Recent evidence indicates that Gram-negative bacterial pathogens, the most common of which are Pseudomonas spp., Enterobacteriaceae, and Acinetobacter baumannii, are frequent causes of hospital-acquired infections. This study aims to evaluate the in vitro activity of doripenem and comparator carbapenem antibiotics against Gram-negative clinical isolates collected from COMParative Activity of Carbapenem Testing (COMPACT) study centres in Turkey. METHODS: Ten centres in Turkey were invited to submit Pseudomonas aeruginosa, Enterobacteriaceae, and other Gram-negative isolates from intensive care unit (ICU)/non-ICU patients with complicated intra-abdominal infections, bloodstream infections, or nosocomial pneumonia, including ventilator-associated pneumonia, between May and October 2008. Susceptibility was determined by each centre using E-test. A central laboratory performed species confirmation as well as limited susceptibility and quality-control testing. RESULTS: Five hundred and ninety six isolates were collected. MIC90 values for doripenem, meropenem, and imipenem, respectively, were 32, ≥ 64, and ≥ 64 mg/L against Pseudomonas spp.; 0.12, 0.12, and 0.5 mg/L against Enterobacteriaceae; and ≥ 64 mg/L for each against other Gram-negative isolates. In determining the susceptibility of hospital isolates of selected Gram-negative pathogens to doripenem, imipenem, and meropenem, we found that against all pathogens combined, the MIC90 for ICU compared with non-ICU isolates was higher. CONCLUSIONS: Doripenem showed similar or slightly better activity than meropenem and better activity than imipenem against the Gram-negative pathogens collected in Turkey.

Assessment of the requisites of microbiology based infectious disease training under the pressure of consultation needs.

BACKGROUND: Training of infectious disease (ID) specialists is structured on classical clinical microbiology training in Turkey and ID specialists work as clinical microbiologists at the same time. Hence, this study aimed to determine the clinical skills and knowledge required by clinical microbiologists. METHODS: A cross-sectional study was carried out between June 1, 2010 and September 15, 2010 in 32 ID departments in Turkey. Only patients hospitalized and followed up in the ID departments between January-June 2010 who required consultation with other disciplines were included. RESULTS: A total of 605 patients undergoing 1343 consultations were included, with pulmonology, neurology, cardiology, gastroenterology, nephrology, dermatology, haematology, and endocrinology being the most frequent consultation specialties. The consultation patterns were quite similar and were not affected by either the nature of infections or the critical clinical status of ID patients. CONCLUSIONS: The results of our study show that certain internal medicine subdisciplines such as pulmonology, neurology and dermatology appear to be the principal clinical requisites in the training of ID specialists, rather than internal medicine as a whole.

The effect of a nationwide antibiotic restriction policy on antibiotic usage in a stem cell transplantation unit.

The Turkish Ministry of Health has released a regulation in February 2003 in order to decrease, first the antibiotic expenses and second, inappropriate use of antimicrobial agents. The aim of this study is to assess the impact of this nationwide antibiotic restriction (NAR) in the most active stem cell transplantation unit (SCTU) in Turkey. All patients followed up in SCTU and had received antimicrobial therapy in the period of four months before and after NAR were evaluated retrospectively. The appropriateness of antimicrobial treatments was assessed by two ID specialists and one ID professor. Disagreements between investigators were solved by discussion and review of published guidelines. There were 10 and 25 patients who were on antimicrobial therapy in the 1st (before NAR) and 2nd (after NAR) group, respectively. Seventeen of the patients had undergone allogeneic stem cell transplantation, while 6 were allogeneic bone marrow recipients and 12 were autologous peripheral stem cell recipients. The antibiotic days per patient was 33.4 and 19.4 in the first and second groups respectively (p=0.036). Although it was not significant, the appropriateness of antibiotic regimens used in the second group was higher than the first group (OR: 5, CI: 0.9-26.4, p= 0.059). The significantly lower antibiotic day per patient in the 2nd group may be the result of collaboration between infectious diseases and hematology physicians settled after NAR in our hospital. NAR had reduced the antimicrobial use in our unit mainly by providing collaboration between infectious diseases and hematology departments.

[Prevalence of extrahepatic illnesses in patients with chronic hepatitis b and hepatitis c: retrospective study of 435 patients]. / Kronik hepatit B ve hepatit C saptanan hastalarda ekstrahepatik hastaliklarin sikligi: 435 hastanin retrospektif olarak incelenmesi.

Chronic infections that caused by hepatitis B and C viruses, are important all of the world as a public health problem. Despite intensive control measurements, the incidences of chronic hepatitis B and C virus infections in our country are estimated as 5-7% and 3%, respectively. There are accumulating data of especially autoimmune mediated extrahepatic manifestations of hepatitis B and C virus infections, such as Diabetes Mellitus (DM), Behçet's Disease (BD), hypo- or hyper-thyroiditis and autoimmune diseases. The aim of this study was the retrospective evaluation of 400 chronic B hepatitis (CBH) and 35 C hepatitis (CCH) patients by means of the presence of extrahepatic manifestations. As a result, the positivity rates of extrahepatic manifestations detected in CBH and CCH patients were as follows respectively; 1.5% and 8.5% for DM, 1.5% and 5.7% for hypothyroiditis, 0.75% and 2.8% for hyperthyroiditis, 2% and 20% for nodular goitre, 0.25% and 5.7% for BD, 1% and 0% for systemic lupus, 1% and 5.7% for Rheumatoid Arthritis (RA), and 22% and 11.4% for iron deficiency anemia. DM, thyroid diseases and RA were the most common extrahepatic manifestations detected in both of the patient groups, while the rates of DM, BD and nodular goitre were found higher in CCH patients than CBH patients (p < 0.05). As a result, the extrahepatic manifestations should be carefully followed in patients with chronic hepatitis B and C infections, for an early diagnosis and appropriate treatment.

The significance of cryoglobulinemia in patients with chronic hepatitis B and C virus infection.

BACKGROUND/AIMS: Mixed cryoglobulinemia is frequently seen in liver disease and chronic viral hepatitis. The aim of this study is to determine the prevalence and clinical findings of cryoglobulins in patients with chronic hepatitis B and chronic hepatitis C. METHODOLOGY: Cryoglobulins were precipitated from serum stored for up to 7 days. The precipitates were washed five times at 4 degrees C with 0.15 mol/L NaCl and total protein concentration was measured by reading absorbance at 280 nm. RESULTS: The prevalence of cryoglobulinemia was higher in patients with hepatitis C than in patients with hepatitis B (16.6% and 4.6% respectively). Patients with cryoglobulinemia had several symptoms such as arthralgia and weakness. CONCLUSIONS: Cryoglobulin-positive chronic hepatitis B and C patients should be investigated in terms of cryoglobulinemia symptoms and complications.

[Thrombocytopenia cases due to acute brucellosis]. / Akut brusellozise bagli trombositopeni olgulari.

The hematological manifestations of brucellosis include anemia, leucopenia, thrombocytopenia and clotting disorders. In this case report, two patients, with clinically and serologically proven brucellosis, manifesting with thrombocytopenia were presented. The first patient who was a 32 years old man, was admitted to the hospital with the complaints of fever, malaise and night sweats. His Brucella agglutination titer was 1/1280 and thrombocyte count was 41.000/mm3. The second case was a 46 years old man with the complaints of fever and rash. His Brucella agglutination titer was 1/640, thrombocyte count was 38.000/mm3. Following treatment with doxycycline and rifampisin the thrombocyte counts of the patients returned to normal (respectively, 176.000/mm3 and 162.000/mm3. The blood cultures of both of these patients did not yield Brucella. The antibiotic therapy of patients discontinued after 6 weeks, with full recovery.