Treatment of tomato paste wastewater by electrochemical and membrane processes: process optimization and cost calculation

This study investigated the treatment of wastewater from tomato paste (TP) production using electrocoagulation (EC) and electrooxidation (EO). The effectiveness of water recovery from the pretreated water was then investigated using the membrane process. For this purpose, the effects of independent control variables, including electrode type (aluminum, iron, graphite, and stainless steel), current density (25-75 A/m2), and electrolysis time (15-120 min) on chemical oxygen demand (COD) and color removal were investigated. The results showed that 81.0% of COD and 100% of the color removal were achieved by EC at a current density of 75 A/m2, a pH of 6.84 and a reaction time of 120 min aluminum electrodes. In comparison, EO with graphite electrodes achieved 55.6% of COD and 100% of the color removal under similar conditions. The operating cost was calculated to be in the range of $0.56-30.62/m3. Overall, the results indicate that EO with graphite electrodes is a promising pretreatment process for the removal of various organics. In the membrane process, NP030, NP010, and NF90 membranes were used at a volume of 250 mL and 5 bar. A significant COD removal rate of 94% was achieved with the membrane. The combination of EC and the membrane process demonstrated the feasibility of water recovery from TP wastewater.

A combined process of chemical precipitation and aerobic membrane bioreactor for treatment of citric acid wastewater

The wastewater generated from citric acid production has a high organic loading content. The treatment and reuse of citric acid wastewater with high organic loading become extremely important. In this study, the performance of calcium hydroxide (Ca(OH)₂) precipitation as a low-cost and environmentally friendly pre-treatment method and aerobic membrane bioreactor (MBR) combined treatment system was investigated for the treatment of citric acid (CA) wastewater. At the first step, optimization parameters such as agitation speed (100, 150, 200 rpm), temperature (30, 50, 70 °C), and reaction time (2, 4, 6 h) for Ca(OH)₂ precipitation as a pre-treatment method were investigated using response surface methodology (RSM) to achieve maximum chemical oxygen demand (COD) removal. Experimental sets were designed using Box-Behnken Design. As a result of pre-treatment with Ca(OH)₂ precipitation, a COD removal efficiency of 97.3% was obtained. Then, pre-treated CA wastewater was fed continuously to the MBR process for 10 days, which was the second stage of the combined process. As a result of the MBR process, 92.0% COD removal efficiency was obtained for 24 h HRT and 10 days SRT. In total, 99.8% COD removal efficiency was obtained when combined process was used and COD concentration decreased from 52,000-114 mg/L. For the treatment and reuse of wastewater from citric acid production, Ca(OH)₂ precipitation and MBR combined treatment systems demonstrated an effective strategy.

Green synthesis of iron oxide nanoparticles derived from water and methanol extract of Centaurea solstitialis leaves and tested for antimicrobial activity and dye decolorization capability

In this research, nanoparticles derived from water extract of Centaurea solstitialis leaves were used as green adsorbent in Fenton reaction for Reactive Red 180 (RR180) and Basic Red 18 (BR18) dyes removal. At optimum operating conditions, nanoparticles proved high performance in the tested dyes removal with more than 98% of removal elimination. The free-radical scavenging, DNA nuclease, biofilm inhibition capability, antimicrobial activity, microbial cell viability, and antimicrobial photodynamic therapy activities of the iron oxide nanoparticles (FeO-NPs) derived from water and methanol extract of plant were investigated. Each of the following analysis: SEM-EDX, XRD, and Zeta potential was implemented for the prepared NPs characterization and to describe their morphology, composition and its behavior in an aqueous solution, respectively. It was found that, the DPPH scavenging activities increased when the amount of nanoparticles increased. The highest radical scavenging activity achieved with FeO-NPs derived from water extract of plant as 97.41% at 200 mg/L. The new green synthesized FeO-NPs demonstrated good DNA cleavage activity. FeO-NPs showed good in vitro antimicrobial activities against human pathogens. The results showed that both synthesized FeO-NPs displayed 100% antimicrobial photodynamic therapy activity after LED irradiation. The water extract of FeO-NPs and methanol extract of FeO-NPs also showed a significant biofilm inhibition.

Functional and Radiologic Results of Posteromedial Limited Surgery in Developmental Dysplasia of the Hip

PURPOSE OF THE STUDY In treatment algorithm of developmental dysplasia of the hip, posteromedial limited surgery is placed between closed reduction and medial open articular reduction. The aim of the present study was to assess the functional and radiologic results of this method. MATERIAL AND METHODS This retrospective study was performed in 37 Tönnis grade II and III dysplastic hips of 30 patients. The mean age of the patients at operation was 12.4 months. The mean follow-up time was 24.5 months. Posteromedial limited surgery was applied when sufficient stable concentric reduction was not achieved by closed technique. No pre-operative traction was applied. Postoperatively, human position hip spica cast was applied for 3 months. Outcomes were evaluated regarding modified McKay functional results, acetabular index and presences of residual acetabular dysplasia or avascular necrosis. RESULTS Thirty-six hips had satisfactory and one hip had poor functional result. The mean pre-operative acetabular index was 34.5 degrees. It improved to 27.7 and 23.1 degrees at the postoperative 6th month and the last control X-Rays. The change in acetabular index was statistically significant (p<0.05). At the last control, 3 hips had findings of residual acetabular dysplasia and 2 hips had avascular necrosis. CONCLUSIONS Posteromedial limited surgery for developmental dysplasia of the hip is indicated when closed reduction remains insufficient and medial open articular reduction remains unnecessarily invasive. This study, in line with the literature, provides evidences that this method might decrease the incidences of residual acetabular dysplasia and avascular necrosis of the femoral head. Key words: developmental dysplasia of the hip, posteromedial limited surgery, closed reduction, medial open reduction.

Antimicrobial and antioxidant activity of phenolic extracts from walnut (Juglans regia L.) green husk by using pressure-driven membrane process

In this study, antioxidant (DPPH and metal chelating), DNA cleavage, biofilm, and antimicrobial properties of extracted phenol from the walnut green husk (WGH) and its different concentrate and permeate samples were evaluated. For maximum phenolic compound extraction from the WGH first, the effects of solvent type (deionized water, methanol, n-hexane, acetone, and ethanol), solvent temperature (25-75 °C), and extraction time (0.5-24 h) were optimized. Then to concentrate phenolic compounds a pressure-driven membrane process was used with four different membrane types. The phenol contents of the concentrate samples were found to be microfiltration (MF) concentrate 4400 mg/L, ultrafiltration (UF) concentrate 4175 mg/L, nanofiltration (NF) concentrate 8155 mg/L, and reverse osmosis (RO) concentrate 8100 mg/L. LC-MSMS was used to determine the quantification of phenolic compounds in permeate and concentrate streams. In addition, all of the concentrate samples with high phenol content showed a high antioxidant activity as 100% with MF concentrate, UF concentrate, NF concentrated and RO concentrated. Likewise, concentrate samples were found to have very high antibiofilm activity as 82.86% for NF concentrate againts S. aureus, 85.80% for NF concentrate against P. aureginosa, 80.95% for RO concentrate against S. aureus, and 83.61% for RO-concentrate against P. aureginosa. When the antimicrobial activity of the extracted phenol from WGH and its different concentrate and permeate samples were evaluated by micro dilution and disk diffusion methods, it was found that the ability of the concentrate samples to inhibit bacterial growth was much higher than permeate ones. In addition, extracted phenol from WGH and its different concentrate and permeate samples showed significant DNA nuclease activity.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-022-05588-w.

Iron-loaded leonardite powder for Fenton oxidation of Reactive Red 180 dye removal

Fenton oxidation is an effective and valuable method for wastewater treatment. To inhibit environmental impacts and increase overall reaction efficiencies, it is important to develop advanced catalysts. This paper illustrates an experimental study on the elimination of RR180 dye from synthetic aqueous solutions with raw leonardite and different iron-loaded leonardite powders, Fe(0)-loaded leonardite, and Fe(II)-loaded leonardite. The effect of solution pH (2.0-6.0), catalyst amount (0.10-1.5 g/L), H₂O₂ concentration (10-50 µL/L), and dye concentration (10-30 ppm) was tested to achieve maximum color removal efficiency using the three catalysts. At pH = 2, color removal efficiencies were higher and more suitable. Initial experiments showed the advantage of using Fe(II)-loaded leonardite on using Fe(0)-loaded leonardite. Fe(II)-loaded leonardite catalyst was the most efficient in RR180 color removal compared to the other tested reagents. Color removal in function of solution pH did not decrease much when Fe(II)-loaded leonardite was used (100 to 96%) when pH was increased from 2.0 to 6.0. In the other hand, dye removal has been significantly affected in the case of using raw leonardite, Fe(0)-loaded leonardite (93 to 0%), and (100 to 13%) in the same pH range, respectively. At optimum experimental conditions, catalyst amount: 0.75 g/L for Fe(II) and Fe(0)-loaded leonardite and 1.5 g/L for raw leonardite; dye concentration: 10 ppm; solution pH: 2.0; H₂O₂ concentration: 50 µL/L; volume: 100 mL and reaction time: 60 min, RR180 dye removal efficiencies were 91%, 100%, and 100% by raw leonardite, Fe(0)-loaded leonardite and Fe(II)-loaded leonardite, respectively. The stability and reusability of the tested catalyst was investigated up to ten cycles. The experimental results revealed that both Fe(0)-loaded leonardite and Fe(II)-loaded leonardite can be used in Fenton reaction up to four cycles without decreasing their efficiency in RR180 color removal. The characterization of the catalysts was established using scanning electron microscope with energy dispersive X-ray spectroscopy (SEM-EDX). The synthesized catalyst can be used at large scale in any textile industry to effectively remove dyes resulting in high elimination rates at the optimal determined and studied conditions.

Comparison of Cr(VI) adsorption and photocatalytic reduction efficiency using leonardite powder

It is very important to treat Cr(VI) from the aquatic environment due to its toxic and harmful effects. Conventional treatment methodology involving biological pathways is generally ineffective for wastewater containing Cr(VI). Therefore, it is necessary to develop environmentally friendly and economical methods to remove Cr(VI) from the aquatic environment. In this study, leonardite, which is a natural mineral that has no harmful effects on the environment, was used for Cr(VI) removal. Leonardite was used in both adsorption and photocatalytic treatment systems by only pulverizing without any chemical treatment. Characterizations of leonardite were obtained using X-ray fluorescence (XRF), fouirer transform infrared spektrofotometre (FTIR), scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX) analyses methods. The effects of solution pH (2-10), particle size (45-300 μm), adsorbent dose (0.25-3 g/L), and initial concentration (10-30 mg/L) on Cr(VI) removal efficiency were investigated in both adsorption and photocatalytic experiments. In the adsorption process, a complete removal efficiency (100%) was obtained for 3 g/L of adsorbent dose with an initial Cr(VI) concentration of 10 mg/L at pH 2 for 2 h. In the photocatalytic process, 100% removal efficiency of Cr(VI) was obtained when four times less adsorbent dosage was used under the same conditions. In addition, the reuse of leonardite powder was also investigated under optimum experimental conditions. Leonardite powder preserved approximately 70% of its activity in the photocatalytic process while it lost 50% of its activity after 5 reuses in adsorption process.

Leonardite powder as an efficient adsorbent for cationic and anionic dyes

This paper aims to investigate the uses of leonardite powder (LP) as an effective adsorbent for the removal of basic red 18 (BR18) and reactive red 180 (RR180) dyes. LP was characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Zeta potential, Brunauer-Emmett-Teller (BET) analysis, Fourier transform infrared spectroscopy (FTIR), and X-ray fluorescence (XRF). The adsorption process was assessed based on pH, size and the amount of the adsorbent, BR18 and RR180 concentration, and the contact time. BR18 dye was completely adsorbed onto the LP (the removal efficiency equals 100%) after 45 min at the optimum condition (original pH [6.5], the particle size of 45 μm, the adsorbent dose of 0.25 g/L, and the initial concentration of 10 mg/L). For RR180, the maximum removal efficiency (74%) was obtained when 1 g/L LP with 45 um size was added to an RR180 solution of 10 mg/L concentration. Temkin isotherm was used to explain the adsorption of BR18. In contrast, RR180 adsorption was described by the Freundlich model. The adsorptions of both dyes followed the pseudo-second-order kinetics. The reusability of the LP was assessed. For BR18, the efficiency decreased to 96% in the second cycle and reached 42% in the fifth cycle. In RR180, LP was not able to be reused efficiently. As a result, the LP ability for BR18 removal is higher than the RR180 in terms of uptake and reusability. PRACTITIONER POINTS: BR18 and RR180 dyes elimination was carried out with leonardite powder (LP). The maximum removal efficiencies for BR18 and RR180 were 100% and 74%, respectively. The LP ability for BR18 removal is higher than the RR180 in terms of uptake and reusability.

The effect of blue thermal treatment on endodontic instruments and apical debris extrusion during retreatment procedures

AIM

To determine the effect of blue thermal treatment on Reciproc (VDW, Munich, Germany) endodontic instruments and the amount of apically extruded debris during retreatment procedures.

METHODOLOGY

Thirty extracted mandibular molar teeth having mesial roots with a degree of curvature less than 20° and having an initial apical size equivalent to a size 10 K-file were selected. The mesial roots of the teeth were removed from the cementoenamel junction to obtain a 15-mm root length. The mesiobuccal canals were prepared to size F2 using the ProTaper Universal system (Dentsply Sirona, Ballaigues, Switzerland), filled with gutta-percha and 2Seal (VDW) using the lateral compaction technique and then randomly divided into two groups (n = 15). The root fillings were removed with one of the following instruments using a crown-down preparation technique: M-Wire Reciproc or Reciproc Blue (both VDW). Apically extruded debris was collected in pre-weighed Eppendorf tubes. The Eppendorf tubes were then stored in an incubator at 70 °C for five days to evaporate the distilled water. The data were analysed using the Mann-Whitney U test (P = 0.05).

RESULTS

Reciproc Blue (1.42 ± 0.4491 mg) extruded significantly less debris apically than M-Wire Reciproc (2.56 ± 1.0232 mg) (P < 0.05).

CONCLUSIONS

Blue thermal treatment of Reciproc instruments was associated with less debris extrusion during retreatment procedures.

Cabergoline treatment in prolactinoma: Amelioration in obstructive and central sleep apneas

A 44-year-old male patient was admitted to the otolaryngology department with a history of progressive snoring, excessive daytime sleepiness, and reduced libido for the last 6 months. Polysomnography demonstrated the presence of moderate obstructive sleep apnea (OSA) with an apnea-hypopnea index (AHI) of 24.6 events/h, consisting of 77 obstructive and 59 central apneas. The marked number of central apneas in the sleep study and urologic complaints prompted the performance of brain magnetic resonance imaging (MRI), which indicated a pituitary macroadenoma (prolactinoma). Three months after treatment with cabergoline, a control MRI showed a significant reduction in the size of the macroadenoma. The AHI was also significantly decreased (to 11.6 events/h), as were the numbers of obstructive and central apneas. The patient's complaints regarding libido were also regressed. During this treatment period, CPAP therapy has not been tolerated by the patient. Cabergoline treatment reduced the severity of both obstructive and central sleep apneas in this patient.

Common coeliacomesenteric trunk: a computed tomography radiological study

BACKGROUND

There is an increasing trend for administration of invasive radiological interventions, laparoscopic surgery, and transplantation procedures in recent years, and determining the vascular variations prior to these procedures is crucially important. Coeliacomesenteric trunk (CMT) is among these variations. This study aimed to retrospectively evaluate this rare anomaly by computed tomography (CT).

MATERIALS AND METHODS

A total of 1000 CT angiography images were analysed retrospectively, and the patients with mesenteric and coeliac arteries arising from the abdominal aorta with a single root were identified. The level that CMT arose, and its branching patterns were determined individually for all patients.

RESULTS

Ten patients (6 males and 4 females) with a mean age of 50.2 years (17-87 years) had CMT in CT images.

CONCLUSIONS

The knowledge of variations in the CMT prior to vascular or laparoscopic interventions will contribute to early intervention in case of a complication, or to avoid from a potential damage.

The force required to fracture endodontically roots restored with various materials as intra-orifice barriers

OBJECTIVE

To evaluate the effect of various materials as intra-orifice barriers on the force required fracture roots.

MATERIALS AND METHODS

One hundred-thirty five mandibular premolars were decoronated and prepared up to size #40. The root canals were filled and randomly divided into two control and seven experimental groups (n = 15), as follows: Positive control group (the intra-orifice barrier cavity was not prepared), negative control group (the intra-orifice barrier cavity was prepared, but not filled), filling using glass ionomer cement, nano-hybrid composite resin, short fiber-reinforced composite, bulk-fill flowable composite, MTA Angelus, Micro Mega MTA or Biodentine. A fracture strength test was performed, and the data were analyzed using one-way ANOVA and Tukey's post hoc tests.

RESULTS

Nano-hybrid composite, short fiber-reinforced composite, bulk-fill flow able composite, and glass ionomer cement increased the force required fracture the roots compared to the positive and negative control groups (P < 0.05). While MTA groups did not increase the force required fracture the roots compared to the control groups, Biodentine increased significantly.

CONCLUSIONS

Within the limitations of the present study, the use of nano-hybrid composite, short fiber-reinforced composite, bulk-fill flowable composite, and glass ionomer cement as an intra-orifice barrier may be useful in reinforcing roots. MTA placement (MTA Angelus or Micro Mega MTA) did not significantly increase the fracture resistance of endodontically treated roots compared to the control groups, however Biodentine did.

Effectiveness of laser-assisted irrigation and passive ultrasonic irrigation techniques on smear layer removal in middle and apical thirds

The purpose of this study was to investigate the evaluation of laser-assisted irrigation (LAI) on the removal of the smear layer as compared to passive ultrasonic irrigation (PUI). Forty-eight single-rooted, upper-central incisor teeth were selected and prepared with ProTaper rotary instruments up to size #40 (F4) at the working lengths. Specimens were divided into four groups, as follows: (a) PUI with 5 mL of 2.5% NaOCl for 60 s; (b) PUI with 2.5 mL of 17% EDTA and 2.5 mL of 2.5% NaOCl each for 30 s; (c) LAI with 5 mL of 2.5% NaOCl for 60 s; and (d) LAI with 2.5 mL of 17% EDTA and 2.5 mL of 2.5% NaOCl each for 30 s. In the PUI groups, the ultrasonically activated file was inserted 1 mm short of the working length, but in the LAI groups, the fiber tip was applied into the pulp chamber. LAI in the pulp chamber with the combination of 17% EDTA and 2.5% NaOCl removed more of the smear layer than the other groups (p < 0.018). LAI in the pulp chamber with the combination of 2.5% NaOCl and 17% EDTA better removed the smear layer than LAI applied similarly but without EDTA or PUI with the same NaOCl and EDTA combinations using an ultrasonically activated file inserted 1 mm short of the working length.

Corticosteroid hypersensitivity in allergic rhinitis

Corticosteroid hypersensitivity in allergic rhinitis.

BACKGROUND

intranasal corticosteroid (IC) is the most effective treatment method in allergic rhinitis patients who are unresponsive to antihistamines. The literature reports an approximate 20% treatment failure for instances where IC is used for the treatment allergic rhinitis. Hypersensitivity reaction to corticosteroids may be one of the causes of this treatment failure.

OBJECTIVE

to discover the incidence and confounding factors of corticosteroid hypersensitivity in patients with allergic rhinitis.

METHODS

after 31 patients were excluded, 150 consecutive patients who were prospectively evaluated in our outpatient clinics with the diagnosis of allergic rhinitis and 50 age- and sex- matched healthy volunteers were included in this study. To diagnose allergic rhinitis, the symptoms of patients and a skin prick test were used. A skin patch test was used to determine corticosteroid hypersensitivity. Total IgE values and total eosinophil count were obtained for all patients. Total symptom scores were calculated for the severity of symptoms and to determine the response to therapy using intranasal corticosteroids.

RESULTS

the incidence of corticosteroid hypersensitivity determined via the skin patch test was 14.0% (21 out of 150 patients). A difference was observed for patch test positivity results between the study and control groups (14% vs. 0%, respectively). Serum IgE levels and total eosinophil count were higher among patients who had corticosteroid hypersensitivity (p:0.005 and p:0.004, respectively). Patients unresponsive to intranasal corticosteroids had a higher incidence of corticosteroid hypersensitivity (71.4% vs. 4.4%, p<0.00 1).

CONCLUSION

our study is the largest to date investigating CH in patients with allergic rhinitis and patients with allergic rhinitis have been found to have a high incidence (14%) of corticosteroid hypersensitivity, which may affect the response of patients to intranasal corticosteroid treatment.

Assessment of root surfaces of apicected teeth: a scanning electron microscopy evaluation

OBJECTIVES

The aim of this study was to determine the apical surface characteristics and presence of dental cracks in single-rooted premolars, resected 3.0 mm from the root apex, using the Er: YAG laser, tungsten carbide bur, and diamond-coated tip, by scanning electron microscopy (SEM).

EXPERIMENTAL DESIGN

Thirty single-rooted premolar teeth were collected. The instrumented and obturated teeth were divided into three groups according to the root resection method (2.94 μm, 100 mj, 20-Hz Er: YAG laser, plain tapered fissure tungsten carbide bur at a low speed of 40,000 rpm, or a diamond-coated SG6D tip coupled to the handpiece of a conventional ultrasound device). The specimens were prepared for SEM and analyzed by the Kruskal-Wallis and Mann-Whitney statistical tests.

RESULTS

The SEM images showed that tungsten carbide burs produced significantly smoother resected root surfaces than the diamond-coated tip. There was no statistically significant difference between the Er: YAG and tungsten carbide bur groups. The analysis of scores obtained for the cut quality by the Kruskal-Wallis test revealed no significant differences among the groups. In our study, five teeth had no cracks after the apical resection. The mean number of cracks per tooth was 3.5 ± 1.780 (Er: YAG laser group), 2.5 ± 1.716 (tungsten carbide bur group), and 4.5 ± 2.593 (diamond-coated tip group).

CONCLUSIONS

Under the tested conditions smoother surfaces were observed in the groups treated with the tungsten carbide bur and Er: YAG laser when compared with the diamond-coated tips.

Comparison of apically extruded debris after root canal instrumentation using Reciproc(®) instruments with various kinematics

AIM

To assess the amount of apically extruded debris using Reciproc(®) instruments with different kinematics (150° counter clockwise [CCW]-30° clockwise [CW], 270° CCW-30° CW, 360° CCW-30° CW and continuous rotation).

METHODOLOGY

Forty-eight maxillary central incisors were selected and assigned to four root canal shaping groups as follows (n = 12): 150° CCW-30° CW, 270° CCW-30° CW, 360° CCW-30° CW and continuous rotation. Reciproc R25 and R50(®) instruments were used in all groups. Apically extruded debris was collected and dried in preweighed Eppendorf tubes. The weight of extruded debris was assessed with an electronic balance. The data were analysed with one way analysis of variance and LSD post hoc tests (P = 0.05).

RESULTS

The 150° CCW-30° CW and 270° CCW-30° CW reciprocating motions extruded significantly less debris than continuous rotation (P < 0.05). However, no significant differences were found between the 360° CCW and 30° CW reciprocating motion and the continuous rotation (P > 0.05).

CONCLUSIONS

All instrument movements were associated with apically extruded debris. However, the 150° CCW-30° CW and 270° CCW-30° CW reciprocating motions were associated with less extrusion than continuous rotation.

A review of instrumentation kinematics of engine-driven nickel-titanium instruments

Over the years, NiTi alloys have become indispensable materials in endodontic treatment. With technological advancements in metallurgy, manufacturers have attempted to produce instruments with enhanced features. In parallel with these developments, endodontic motors have undergone improvements in terms of torque control and kinematics that are adjustable in different directions. This review presents an overview of the advancements in instrumentation kinematics and the effect of instrumentation kinematics on root canal shaping procedures and instrument performance. The literature search for this narrative review was conducted in Google Scholar, Scopus, PubMed and Web of Science using the keywords 'kinematics and endodontics' and 'reciprocation and endodontics'. In addition, historical literature was searched using the keyword 'nickel-titanium and endodontics'. Overall, 143 articles were included up to 2015.

Antimicrobial susceptibilities of uropathogen Escherichia coli in renal transplant recipients: dramatic increase in ciprofloxacin resistance

The urinary tract is the most common site of bacterial infections in renal transplant recipients. The management of urinary tract infections (UTI) in renal transplant recipients is becoming more difficult because of drug-resistant bacteria. The antimicrobial susceptibilities of uropathogen bacteria isolated from 398 patients who underwent renal transplantation between 2007 and 2011 were obtained from medical records. At least 1 UTI episode was diagnosed in 172 (43.2%) patients. Among the 703 bacteria isolated from these patients, Exherichia coli the most common pathogen, was isolated from 407/703 episodes (57.8%). Ciprofloxacin, co-trimoxazole, ceftriaxone, and gentamicin resistance rates were 59.4%, 85.7%, 40.7%, and 36.6%, respectively. Ninty six of 407 E. coli isolates (23.5%) were ESBL positive. Analysis of resistance rates in our center demonstrated ciprofloxacin resistance rate in uropathogenic E. coli to have increased gradually from 30.4% in 2003, 41.3% in 2007, and 59.4% in 2012. Instutional data regarding the etiologic agents and antimicrobial susceptibility results are important for proper management of patients with UTI.

Efficacy of various irrigation protocols on the removal of triple antibiotic paste

AIM

To compare the efficacy of irrigation protocols on the removal of triple antibiotic paste (metronidazole, ciprofloxacin and minocycline) (TAP) from artificial grooves in root canals.

METHODOLOGY

Root canals in 72 extracted single-rooted teeth were prepared using ProTaper rotary instruments up to size F5. The roots were split longitudinally and a standardized groove was prepared in the apical part of one segment. TAP was placed in the grooves, and the root halves were reassembled. The roots were randomly divided into six experimental groups according to the irrigation protocol used: distilled water, 1% NaOCl, 2.5% NaOCl, 100% ethanol, 17% EDTA and passive ultrasonic irrigation (PUI) with 1% NaOCl. The root segments were disassembled, and the amount of TAP remaining was evaluated under a stereomicroscope at 20× magnification using a four-grade scoring system. The data were evaluated statistically using Kruskal-Wallis and Mann-Whitney U-tests with a 95% confidence level (P = 0.05).

RESULTS

There were significant differences amongst the groups (P < 0.001). Passive ultrasonic irrigation (PUI) with 1% NaOCl removed significantly more TAP than the other irrigating solutions (P < 0.05). Distilled water, 1% NaOCl, ethanol and EDTA were associated with significantly more remaining TAP.

CONCLUSIONS

PUI with 1% NaOCl was more effective in removing TAP from artificial grooves in root canals than other irrigating solutions without ultrasonic agitation. It was not possible completely to remove TAP from root canals.

Micro-tensile bond strength of adhesives to pulp chamber dentin after irrigation with Ethylenediaminetetraacetic acid

Aim:

The aim of this study was to evaluate the influence of different concentrations of Ethylenediaminetetraacetic acid (EDTA) solution on adhesion, that is, the bond strength of the different adhesive systems, to the pulp chamber dentin.

Materials and Methods:

Recently extracted, sound, human, third molars were cut horizontally to expose the pulp horn. The roof of the pulp chamber and pulp tissue was removed. The teeth were then divided into five main groups. The teeth in each group were treated as follows: group 1, irrigated with saline; group 2, with 5% EDTA for 5 minutes; group 3, with 15% EDTA for 5 minutes; group 4, with 17% EDTA for 5 minutes and group 5, with 19% EDTA for 5 minutes. Treated specimens were dried and divided into 2 subgroups for adhesives; bonded with a total-etching adhesive (Adper Scotchbond Multi-purpose - ASB) or a one bottle of self-etch adhesive system (Clearfil S3 Bond – CS3). After the bonding procedure and composite restoration, teeth were sectioned and dentin sticks were obtained from each group for micro tensile testing (n = 10). Micro tensile testing was performed and scanning electron microscope (SEM) photographs were taken for each irrigated group.

Results:

In the ASB group, saline showed statistically higher bond strength values at the different concentrations of EDTA, while the micro-tensile bond strengths of the different concentrations of EDTA were not statistically different. In the CS3 group, saline and 5% EDTA showed statistically higher bond strength values than 17% and 19% EDTA, while the micro-tensile bond strengths of 15% EDTA compared to saline and 5% EDTA and 15% EDTA compared to 17% EDTA and 19% EDTA, were not statistically different.

Conclusion:

This study showed that EDTA irrigation can affect the bond strength of adhesive systems on pulp chamber lateral walls. Clinically, low EDTA concentrations can be recommended if self-etch adhesives have been selected.

Spinal tanycytic ependymoma with diffusion restriction on MRI

Tanycytic ependymoma is a rare spindle-cell variant of ependymoma derived from tanycytes. Primitive neuroectodermal tumors usually have diffusion restriction, whereas ependymomas do not. Here, we present a case of tanycytic ependymoma with diffusion restriction. As far we are aware, this is the first case of tanycytic ependymoma in the English literature with diffusion restriction.

Risk factors for extended-spectrum beta-lactamase positivity in uropathogenic Escherichia coli isolated from community-acquired urinary tract infections

The aim of this prospective cohort study was to determine the risk factors for community-acquired urinary tract infections (UTIs) caused by extended-spectrum beta-lactamase (ESBL)-positive Escherichia coli and the distribution of the ESBL enzyme types. Structured forms were filled in for patients diagnosed with community-acquired UTI in four different geographical locations in Turkey. The forms and the isolates were sent to the central laboratory at Baskent University Hospital, Ankara. Antimicrobial susceptibility was determined according to the CLSI criteria. PCR and DNA sequencing were used to characterize the bla(TEM), bla(CTX-M) and bla(SHV) genes. Multivariate analysis was performed using logistic regression. A total of 510 patients with UTI caused by Gram-negative bacteria were included in this study. ESBLs were detected in 17 of 269 (6.3%) uropathogenic E. coli isolates from uncomplicated UTIs and 34 of 195 (17.4%) E. coli isolates from complicated UTIs (p <0.001). According to multivariate analysis, more than three urinary tract infection episodes in the preceding year (OR 3.8, 95% CI 1.8-8.1, p <0.001), use of a beta-lactam antibiotic in the preceding 3 months (OR 4.6, 95% CI 2.0-0.7, p <0.001) and prostatic disease (OR 9.6, 95% CI 2.1-44.8, p 0.004) were found to be associated with ESBL positivity. The percentages of isolates with simultaneous resistance to trimethoprim-sulphamethoxazole, ciprofloxacin and gentamicin were found to be 4.6% in the ESBL-negative group and 39.2% in the ESBL-positive group (p <0.001). Forty-six of 51 ESBL-positive isolates (90.2%) were found to harbour CTX-M-15. Therapeutic alternatives for UTI, particularly in outpatients, are limited. Further clinical studies are needed to guide the clinicians in the management of community-acquired UTIs.