A microfluidic chip-based capillary zone electrophoresis-mass spectrometry method for measuring adenosine 5'-Triphosphate and its similar nucleotide analogues

BACKGROUND

Extracellular ATP is involved in disorders that cause inflammation of the airways and cough, thus limiting its release has therapeutic benefits. Standard luminescence-based ATP assays measure levels indirectly through enzyme degradation and do not provide a simultaneous readout for other nucleotide analogues. Conversely, mass spectrometry can provide direct ATP measurements, however, common RPLC and HILIC methods face issues because these molecules are unstable, metal-sensitive analytes which are often poorly retained. These difficulties have traditionally been overcome using passivation or ion-pairing chromatography, but these approaches can be problematic for LC systems. As a result, more effective analytical methods are needed.

RESULTS

Here, we introduce a new application that uses microfluidic chip-based capillary zone electrophoresis-mass spectrometry (μCZE-MS) to measure ATP and its analogues simultaneously in biofluids. The commercially available ZipChip Interface and a High-Resolution Bare-glass microchip (ZipChip, HRB, 908 Devices Inc.) coupled to a Thermo Scientific Tribrid Orbitrap, were successfully used to separate and detect various nucleotide standards, as well as ATP, ADP, AMP, and adenosine in plasma and BALF obtained from naïve Brown Norway rats. The findings demonstrate that this approach can rapidly and directly detect ATP and its related nucleotide analogues, while also highlighting the need to preserve these molecules in biofluids with chelators like EDTA. In addition, we demonstrate that this μCZE-MS method is also suitable for detecting a variety of metabolites, revealing additional potential future applications.

SIGNIFICANCE

This innovative μCZE-MS approach provides a robust new tool to directly measure ATP and other nucleotide analogues in biofluids. This can enable the study of eATP in human disease and potentially contribute to the creation of ATP-targeting therapies for airway illnesses.

Understanding boron toxicity in aquatic plants (Salvinia natans and Lemna minor) in the presence and absence of EDTA

Even though boron is a widely used element in various industries and a contributor to water pollution worldwide, few studies have examined the toxicity of boron in aquatic plants. EDTA is used to maintain aquatic plants cultures, however it is possible to modify the toxicity of metals. The objective of this study is to assess the toxicity of boron in aquatic plants and explore the impact of EDTA presence on the resulting toxic responses. Floating watermoss Salvinia natans and duckweed Lemna minor were exposed to concentrations ranging from 5 to 100 mg/L for 7 days and 1 to 60 mg/L for 3 days, respectively. Growth and photosynthetic activity parameters were investigated in the presence and absence of EDTA. Growth inhibitions in both aquatic plants were observed in a concentration-dependent manner, irrespective of the presence or absence of EDTA. For instance, based on the specific growth rate (leaves coverage), EC10 values for S. natans were calculated as 12.7 (9.9-15.3) mg/L and 8.0 (5.8-10.3) mg/L with and without EDTA, respectively. In the case of L. minor, EC10 values were calculated as 1.3 (0.8-1.89) mg/L and 2.0 (0.4-4.3) mg/L with EDTA without EDTA, respectively. Significant effects were also observed on the photosynthetic capacity, however there was no change in the increase of boron concentration. Generally, negligible effects of EDTA to the toxicity of boron were observed in the present study. By comparing toxicity results based on the presence and absence of EDTA, which is an essential element in the test medium, the results of this study are expected to be utilized for the ecological risk assessment of boron in aquatic ecosystems.

Effect of photobiomodulation therapy on TGF-β release from dentin, migration and viability of dental pulp stem cells in regenerative endodontics treatment: An ex vivo study

BACKGROUND AND AIM

Regenerative endodontic procedures (REPs) are oriented by the principles of tissue engineering, incorporating dental pulp stem cells (DPSC), crucial growth factors like Transforming growth factor-β (TGF-β1), and scaffolds to facilitate the regeneration of dental pulp tissues. The present study aimed to investigate the effect of photobiomodulation (PBM) therapy, using an 808 nm diode laser on cellular modulation mechanisms in REPs.

METHOD AND MATERIAL

A total of 108 human dentin discs obtained from intact single root teeth were randomly assigned into six groups (n = 8): 1. Positive control (EDTA), 2. PBM-1 (3 J/cm2), 3. PBM-2 (5 J/cm2), 4. EDTA+PBM-1, 5. EDTA+PBM-2, and 6. Negative control (NaOCl). Then, an extract solution was prepared from each disc and the concentration of released TGF-β1 from the discs was measured using enzyme-linked immunosorbent assay (ELISA). Moreover, the extract solution was added to DPSC culture medium to evaluate cell viability and migration through MTT assay and scratch test, respectively.

RESULT

The group exposed to PBM-1 showed the highest cell viability, while treatment with EDTA and EDTA+PBM-2 decreased cellular viability. Also, the PBM-treated groups showed significantly higher release of TGF-β1 compared to the negative control. EDTA and EDTA+PBM-1 showed the highest release among all the groups. No significant difference was found between EDTA and EDTA+PBM-1, as well as between PBM-1 and PBM-2. Moreover, the PBM-1 group exhibited the highest migration after 24 h, which was significantly greater than other groups, except for the PBM-2 group.

CONCLUSION

According to the obtained data, 808 nm mediated-PBM (3 J/cm2), both independently and in conjunction with EDTA, enhanced the release of TGF-β1 from dentin and improved cell viability and migration of DPSCs. It seems that, PBM under the specific parameters employed in this study, could be an effective adjunctive therapy in REPs.

Novel combination of nanoparticles and metallo-β-lactamase inhibitor/antimicrobial-based formulation to combat antibiotic resistant Enterococcus sp. and Pseudomonas sp. strains

Nanotechnology presents an innovative strategy to combat the spread of antibiotic resistant bacteria and their resistance genes throughout different ecosystems. To address this challenge, nanoparticles (silver, gold, zinc and copper) alone or in combination with metallo-β-lactamase inhibitor/antimicrobial-based formulation (EDTA/HLE) showed antimicrobial activity against antibiotic resistant Enterococcus sp. and Pseudomonas sp. strains. Furthermore, the observed synergistic effect was detected notably for silver, zinc or copper nanoparticles with EDTA (ethylenediaminetetraacetic acid) and silver nanoparticles with HLE against planktonic Enterococcus sp. strains, or gold nanoparticles+EDTA or HLE against Pseudomonas sp. Regarding activity against bacterial biofilms, zinc nanoparticles combined with either of the reagents caused strong inhibition of developing biofilms of antibiotic resistant Enterococcus sp. Pseudomonas sp. strains, while preformed biofilms were mainly inhibited by silver nanoparticles+reagent. Microscopic analyses confirmed that the antimicrobial activity of nanoparticles was caused by adsorption to the bacterial cell surface, and further enhanced by chelating agents. Hence, we can conclude that nanoparticles+EDTA or HLE could represent a good alternative to limit the spread of antibiotic resistant bacteria in the food chain and the environment.

Effect of ethylenediaminetetraacetic acid, maleic acid, and fumaric acid on postendodontic treatment root fracture toughness - An in vitro study

Aim

The aim of this study was to evaluate the effectiveness of ultrasonic activation of ethylenediaminetetraacetic acid (EDTA), maleic acid (MA), and fumaric acid (FA) in combination with sodium hypochlorite (NaOCl) on postendodontic treatment root fracture toughness.

Materials and Methods

Forty single-rooted mandibular premolars were sectioned below the cementoenamel junction and were kept on average 14 mm long. With the exception of eight randomly selected teeth acting as a negative control group (Group I/nonprepared), the rest were prepared till F3. Thirty-two specimens were randomly placed into four groups equally and then irrigated using the final irrigation protocols. Saline and NaOCl were used to irrigate Group II, 17% EDTA and NaOCl were used to irrigate Group III, 7% MA and NaOCl were used to irrigate Group IV, and 0.7% FA and NaOCl were used to irrigate Group V. The irrigants were ultrasonically activated in every group. The root canals were obturated with gutta-percha and AH Plus sealer. The roots were embedded along the long axis in the self-curing acrylic blocks along with polyvinyl siloxane, leaving the coronal 2 mm of the root exposed. The specimens were tested using a universal testing machine.

Statistical Analysis

The Post hoc Tamhane's and one-way ANOVA tests were applied to examine the data.

Results

The result of the study revealed that 0.7% FA (598.09 N) provided better root fracture resistance than EDTA (428.07 N) and MA (511.87 N).

Conclusion

The conclusion derived from the study was that 0.7% FA provided better fracture resistance of endodontically treated teeth when compared to 17% EDTA and 7% MA.

Photo-induced photoacoustic streaming and pineapple peel extract as final irrigant on extrusion bond strength of root filling material to canal wall

Objective

Photon-induced photoacoustic streaming (PIPS) with pineapple peel extract (PPE) and ethylenediaminetetraacetic acid (EDTA) as a final endodontic irrigant on the push-out bond strength (PBS) of root filling material to conventional irrigation NaOCl with EDTA.

Methods

An in vitro study at Dar Al Uloom University was conducted over three months. Root canal preparation was performed. Based on final irrigation, all the specimens were divided randomly into four groups (n=10) Group 1: 2.25% NaOCl+ 17% EDTA (control), Group-2: 2.25% NaOCl+PIPS + 6.25% PPE, Group-3: 2.25% NaOCl+PIPS + 17% EDTA, Group-4: 2.25% NaOCl + 6.25% PPE. Canals were obturated and sealed with AH Plus sealer. Root sectioning was performed at 1mm thickness and PBS testing was performed using the universal testing machine. The debonded samples were analyzed for failure mode. ANOVA compared the means and standard deviations (SD) of all investigated group. Assessment of multiple comparisons was performed using Tukey's post hoc test.

Results

The maximum PBS was demonstrated by the coronal section of Group-2 (2.25%NaOCl +PIPS+6.25%PPE) specimens (8.21±0.81MPa). The apical section of Group-1 (2.25% NaOCl+17% EDTA) specimens demonstrated minimum bond strength (2.80±0.18 MPa). The intergroup comparison revealed that Group-3 (2.25% NaOCl +PIPS +17% EDTA) and Group-2 demonstrated comparable outcomes (p>0.05). Group-4 (2.25% NaOCl +6.25% PPE) specimens established significantly lower values than Group-3 and Group-4 (p<0.05).

Conclusion

Photon-induced photoacoustic streaming with pineapple peel extract and EDTA demonstrated better bond strength of root canal sealer and have the potential to be used as the final irrigant.

In vivo Study to Evaluate the Effect of Instrument Size on the Accuracy of Three Different Apex Locators when Various Irrigation Solutions are used in Vital and Non-Vital Teeth

Introduction

Root canal success requires working length (WL) optimization. The current study examined how different apex locators on vital and non-vital teeth responded to instrument size.

Materials and Methods

Three hundred patients (180 men and 120 women) receiving root canal therapy at the department of Conservative Dentistry and Endodontics were evaluated. Therefore, we determined that 200 of the patients' teeth (100 vital and 100 non-vital teeth from the upper and lower jaws' first molars) qualified for inclusion in our study. The pulp chamber was accessed using a sterile round bur. The coronal region of the root canal was preflared with successive Gates Glidden drills (Mani Inc. Japan) and irrigated with any one of the solutions 3% sodium hypochlorite (NaOCl), 2% chlorhexidine (CHX), or 17% ethylenediaminetetraacetic acid (EDTA) solution after checking canal patency with a size #10 K file, where (#-number). Later, the working length was established using Ingle's technique and a radiovisiograph (RVG) 0.5 mm short of the radiographic apex. Two endodontists approved this RVG.

Results

Overall, the #15 K file and apex locators did not differ from Ingle's method. While the #8 K file differs significantly from all apex locators, the #10 K file showed a significant difference with all apex locators except Root ZX with 2% CHX (P = 0.06). Irrigation didn't influence apex locators' accuracy.

Conclusion

Even in the presence of irrigating solutions, electronic apex locator (EAL) can be utilized to calculate the working length with accuracy. The apex locators #15 k files, #10 k files, and #8 k files showed the most promising results.

Microplastic isolation method for wastewater and sludge samples by removal of excess organic and inorganic interferences

The isolation of microplastics from other organic and inorganic contents is a major hurdle to the effective quantification and characterization of microplastics in wastewater and biosolids samples. As a result, a well-established and standardized isolation method is vital for the analysis of microplastics. In this study, we evaluated biological hydrolysis, enzymatic hydrolysis, wet peroxidation and ethylenediaminetetraacetic acid treatment for microplastics isolation and demonstrated that the integration of these processes can effectively remove organic and inorganic contents to provide a clear microscope view for microplastics identification from wastewater and sludge samples. To the best of our knowledge, this study is the first to introduce biological hydrolysis and ethylenediaminetetraacetic acid treatment for the isolation of microplastics from environmental samples. The results reported could facilitate the establishment of a standardized procedure for microplastic isolation from wastewater and biosolid samples.

Enhancing attachment of human gingival fibroblasts to periodontally compromised teeth: A comparative analysis of hyaluronic acid, EDTA, enamel matrix derivatives

Background

Gingival recession is a characteristic indicator of periodontitis and one of the factors that contributes to increased tooth clinical crown length. Patients with root exposure frequently undergo periodontal surgical procedures in addition to adjunctive therapy to increase root coverage area and soft tissue stability.

Purpose

This study aimed to evaluate fibroblast-root surface adhesion and determine whether periodontitis-damaged root surface microstructure can be restored using ethylenediaminetetraacetic acid (EDTA) and an enamel matrix derivative (EMD), individually or in combination.

Material and methods

Teeth extracted from patients with periodontal disease were used to create 60 samples, with each group containing six specimens. The test groups were provided root planing or root condition-specific materials (hyaluronic acid [HA], 24% EDTA, EMD, or EDTA/EMD) for varying treatment time periods. In contrast, the control group did not undergo any surface modifications. The samples and fibroblast cells were incubated for 72 h. The number of living cells on the root surface in each group was calculated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay (cell viability assessment).

Results

The control, root planing, and EMD groups showed that the root surfaces treated with EDTA for 4 min had significantly better cell adhesion. Surface EDTA treatment for 2 min significantly promoted cell attachment compared to root planing treatment. The root surfaces modified with EDTA/EMD for 2 and 4 min showed significantly improved cellular migration and adhesion compared to the root surface treated with root planing.

Conclusion

EDTA and EDTA/EMD substantially affected the root surface, which was related to the length of the treatment process. This effect shifts the surface properties, alters fibroblast interactions with the root surface, and recruits more cells to cover a larger area.

Comparative study of the antioxidant capability of EDTA and Irganox

Oxidative stress makes it difficult to preserve food and negatively affect the applicability of polymeric packaging. It is typically caused by an excess of free radicals, and it is dangerous to human health, resulting in the onset and development of diseases. The antioxidant ability and activity of ethylenediaminetetraacetic acid (EDTA) and Irganox (Irg) as synthetic antioxidant additives were studied. Three different antioxidant mechanisms were considered and compared by calculating bond dissociation enthalpy (BDE), ionization potential (IP), proton dissociation enthalpy (PDE), proton affinity (PA), and electron transfer enthalpy (ETE) values. Two density functional theory (DFT) methods were used, M05-2X and M06-2X with the 6-311++G(2d,2p) basis set in gas phase. Both additives can be used to protect pre-processed food products and polymeric packaging from oxidative stress related material deterioration. By comparing the two studied compounds, it was found that EDTA has a higher antioxidant potential than Irganox. To the best of our knowledge several studies have been carried out to understand the antioxidant potential of various natural and synthetic species, but EDTA and Irganox were not compared and investigated before. These additives can be used to protect pre-processed food products and polymeric packaging and prevent material deterioration caused by oxidative stress.

Elemental analysis of various demineralized tooth graft by EDX-720 XRF: An in vitro study

Background

The periodontal regeneration is the most challenging process which involves regeneration of both hard and soft tissues. There are various biomaterials available for this purpose. Tooth graft can be used as a regenerative material in the field of periodontics and implantology. The tooth graft with 70% demineralization is considered to be a better option for periodontal regeneration. Different methods are employed for demineralization of tooth using various acids.

Materials and Methods

This study was designed as an in vitro study. Totally 60 teeth were collected and categorized into four groups. Groups I, II, and III teeth were demineralized in 2% nitric acid, 0.6 M hydrochloric acid, and 17% ethylenediaminetetraacetic acid (EDTA), respectively. The Group IV teeth were left undemineralized. The elements present in the various tooth graft groups after demineralization were analyzed by EDX-720 XRF Instrument.

Results

The EDTA demineralized tooth graft has higher level of Calcium, Strontium, and Zinc content compared to other tooth graft groups and it was statistically significant with P = 0.001.

Conclusion

The EDTA demineralized tooth graft can serve as better graft than 2% nitric acid and 0.6M hydrochloric acid demineralized and undemineralized tooth grafts.

Influence of photodynamic therapy, different final irrigants, and ultrasonic activation on the bond strength of glass fiber posts to root dentin

OBJECTIVE

To evaluate the influence of photodynamic therapy (PDT), different final irrigants, and ultrasonic activation (US) on the bond strength of glass fiber posts (GFP) to root dentin.

METHODS

One hundred twenty bovine roots were divided into 12 groups according to PDT application, the type of final endodontic irrigant, and US. The samples were divided into 12 groups (n = 10): G1-DW(distilled water); G2-DW+US; G3-17% EDTA; G4-17% EDTA+US; G5-17% GA (glycolic acid); G6-17% GA+US; G7-PDT+DW; G8-PDT+DW+US; G9-PDT+17% EDTA; G10-PDT+17% EDTA+US; G11-PDT+17% GA; G12-PDT+17% GA+US. After cementing the glass fiber posts with resin cement, roots were sectioned into 2-mm-thick slices. One slice from the cervical third and another from the middle third were used for the push out test (PO), and the other two for the diametral compression test (DC). Thus, 10 samples were obtained per third for each mechanical test (n = 10). Kruskal-Wallis and Student-Newman-Keuls tests were used to analyze PO and DC data, and Pearson's correlation test was used to verify the relationship between the variables. Failure patterns were analyzed with chi-square test.

RESULTS

Significant differences were found in the PO test among the experimental groups (p < 0.001; power=1.00). PDT improved bond strength when using EDTA. PDT and US increased bond strength when using GA. Favorable failure patterns occurred more frequently in Group GA+US. There was no correlation between data obtained with PO and DC tests (r = 0.112; p = 0.729).

CONCLUSION

PDT provided the highest bond strength values of GFP to root dentin when associated with GA and US or when associated only with EDTA.

Fabrication of a porous polyacrylonitrile nanofiber adsorbent for removing radioactive 60Co

A Co²⁺ adsorbent was prepared using electrospun porous polyacrylonitrile (PAN) nanofibers, featuring easy recovery for reuse compared with a nanoparticle-based adsorbent. As an efficient ligand for Co²⁺, ethylenediaminetetraacetic acid (EDTA) was introduced on the surface of porous PAN nanofibers with the aid of a branched polyethyleneimine (PEI) linker to obtain an adsorbent with carboxylic acid groups. On the adsorbent surface, the carboxylic acid and amine groups from EDTA could adsorb Co²⁺ via ion exchange and chelation, and amine groups from PEI that remained after EDTA functionalization played a role in coordinating Co²⁺. The amine and carboxylic acid groups were simultaneously involved in the adsorption on the surface, making it possible to remove Co²⁺ over a wide pH range. An investigation of the adsorption isotherms and kinetics of the nanofibrous adsorbent indicated that monolayer chemisorption was achieved with a maximum Co²⁺ adsorption capacity of 8.32 mg/g. In addition, radioactive ⁶⁰Co was efficiently removed by the adsorbent with a removal extent of more than 98%. Considering the easy separation from Co²⁺ solution and regeneration of the nanofibrous adsorbent and its availability in a wide pH range, the adsorbent has great advantages in practical applications.

The role of iron nanoparticles on morpho-physiological traits and genes expression (IRT1 and CAT) in rue (Ruta graveolens)

The iron nanoparticles with different physic-chemical properties induce inconsistent effects on various studied plant species. Thus, the effect of ferric oxide (Fe₂O₃) nanoparticles was compared with Fe₂O₃ microparticles and FeSO₄complexes of EDTA for major physiological and gene expression in Rue (Ruta graveolens). Iron root content increased as Fe-MPs + EDTA ˂˂ Fe-NPs + EDTA˂ FeSO₄ + EDTA. The shoot's iron remained unchanged or slightly increased under most of FeSO₄ and Fe-MPs + EDTA treatments. Under Fe-NPs + EDTA treatment, 50 and 250 µM concentration decreased on shoot iron by 23.2% and 19.4% compared to control, respectively. But the shoot iron at 500 µM NPs was 28.2% higher than that of the control. A 46-58 fold lower Fe translocation was observed under Fe-NPs + EDTA than Fe-MPs + EDTA. The effect of Fe-NPs + EDTA was more significant on plant fresh and dry mass than the control. All treatments showed an increase in anthocyanin by 19-84% in leaves compared to the control. The Fe-NPs + EDTA and MPs + EDTA induced similar effects on enhanced growth parameters, total chlorophyll, catalase enzyme activity, gene, and reduced chlorophyll a/b and oxidants. Catalase enzyme activity in FeSO₄ and MPs + EDTA was similar, and in Fe-NPs + EDTA treatments were influenced by coarse and fine regulation mechanisms, respectively. Iron MPs + EDTA had a more negative effect on IRT₁ relative gene expression in roots as compared to other iron forms. The IRT₁ relative gene expression in shoots was positively affected by 31-81% under all treatment types (except control and 250 µM Fe-NPs + EDTA, and 250 µM MPs + EDTA). These results could reveal the potential mechanism of plant response to nanoparticles.

Diagnostic value of serum versus plasma phospho-tau for Alzheimer's disease

BACKGROUND

Blood phosphorylated tau (p-tau) forms are promising Alzheimer's disease (AD) biomarkers, but validation in matrices other than ethylenediaminetetraacetic acid (EDTA) plasma is limited. Firstly, we assessed the diagnostic potential of p-tau231 and p-tau181 in paired plasma and serum samples. Secondly, we compared serum and cerebrospinal fluid (CSF) samples from biomarker-positive AD and biomarker-negative control participants.

METHODS

We studied three independent cohorts (n=115 total): cohorts 1 and 2 included individuals with paired plasma and serum, while cohort 3 included paired serum and CSF. Blood-based p-tau231 and p-tau181 were measured using in-house or commercial single molecule array (Simoa) methods.

RESULTS

Serum and plasma p-tau231 and p-tau181 were two- to three-fold increased in biomarker-positive AD versus biomarker-negative controls (P≤0.0008). Serum p-tau231 separated diagnostic groups with area under the curve (AUC) of 82.2% (cohort 3) to 88.2% (cohort 1) compared with 90.2% (cohort 1) for plasma. Similarly, p-tau181 showed AUC of 89.6% (cohort 1) to 89.8% (cohort 3) in serum versus 85.4% in plasma (cohort 1). P-tau231 and p-tau181 correlated slightly better in serum (rho=0.92 for cohort 1, 0.93 for cohort 3) than in plasma (rho=0.88, cohort 1). Within-individual p-tau181 (Quanterix) and p-tau231 concentrations were twice higher in plasma versus serum, but p-tau181 (in-house, Gothenburg) levels were not statistically different. Bland-Altman plots revealed that the relative difference between serum/plasma was larger in the lower range. P-tau levels in paired plasma and serum correlated strongly with each other (rho=0.75-0.93) as well as with CSF Aβ₄₂ (rho= -0.56 to -0.59), p-tau and total-tau (rho=0.53-0.73). Based on the results, it seems possible that serum p-tau reflects the same pool of brain-secreted p-tau as in CSF; we estimated that less than 2% of CSF p-tau is found in serum, being same for both controls and AD.

CONCLUSIONS

Comparable diagnostic performances and strong correlations between serum versus plasma pairs suggest that p-tau analyses can be expanded to research cohorts and hospital systems that prefer serum to other blood matrices. However, absolute biomarker concentrations may not be interchangeable, indicating that plasma and serum samples should be used independently. These results should be validated in independent cohorts.

Removal behavior and mechanisms of cadmium and lead by coupled ethylenediaminetetraacetic acid washing and electrochemical reduction: influence of current conditions

Ethylenediaminetetraacetic acid (EDTA) washing has been used extensively to remediate heavy metal-contaminated soils. Electrochemical reduction treatment of spent washing solution is an effective method of EDTA regeneration. However, at present, these two technologies are usually regarded as two independent treatment processes. This research raised a new heavy metal-contaminated soil treatment strategy-a combination technique of coupled EDTA washing and electrochemical reduction. We speculated that the combination of EDTA washing and electroreduction treatment could improve the efficiency of Cd and Pb removal from contaminated soil. In this study, the removal performance and mechanisms of Cd and Pb under different current conditions were investigated based on a coupling of EDTA washing and electrochemical reduction. The combination technique can increase Cd and Pb removal efficiencies by 13.37-15.24% and 14.91-27.05%, respectively, compared with EDTA washing alone. Sequential extraction analysis showed that the reducible fraction improved metal removal efficiency. The percentage of metal removed increased with an increased current value and EDTA concentration. In addition, pulse current mode removed more Cd and Pb than continuous current, although the difference was not significant (p > 0.05). However, pulse current could effectively eliminate the cathodic hydrogen evolution reaction, resulting in a further heavy metal deposition at the cathode. The combination technique exhibited enhanced removal efficiency due to EDTA regeneration in the suspension and the cathodic reduction reaction. The most cost-effective treatment in 48 h was a pulse current mode of 32 min on/16 min off-32 mA-EDTA-10 mM, where 47.56% of Cd and 77.00% of Pb were removed from the soil with an electric energy consumption of 8.24 Wh.

Comparison of Efficacy of Various Intracanal Irrigants with Ultrasonic Bypass System

BACKGROUND

The long-term success of root canal therapy depends on the effective debridement and removal of smear layer and debris from the canal. Root canals with difficult anatomy and complex systems pose great challenge to achieve this. Mechanical therapy alone cannot achieve this goal, various intracanal chemicals also have their own limitations along with the difficulty in reaching the farfetched and difficult areas, and hence, introduction of ultrasonic bypass system has been a boon for the endodontic therapy.

OBJECTIVES

The aim of this study is to compare the various root canal medicaments along with ultrasonic bypass system in effectively cleaning the debris and smear layer from the various parts of the root canal system.

MATERIALS AND METHODS

Forty single-rooted anterior maxillary and mandibular human teeth were collected for this study, after disinfection, they were sectioned into three equal parts coronal, middle, and apical and these parts were later studies under SEM (Scanning Electron Microscope) and scoring as per the scoring criteria set before the study was done and results were then compared statistically.

RESULTS

Group with both ethylenediaminetetraacetic acid (EDTA) and NaOCl with ultrasonic bypass system was the most effective one, when compared with sterile water, NaOCl + ultrasonic bypass system, EDTA + ultrasonic bypass system. NaOCl + ultrasonic bypass system was more effective as compared with the EDTA + ultrasonic bypass system.

CONCLUSION

Ultrasonic bypass system is a useful tool for debris and smear layer removal from a root canal system, but its effectiveness increases when both EDTA and NaOCl are used along with it.

Evaluation of Free Available Chlorine of Sodium Hypochlorite When Admixed with 0.2% Chitosan: A Preliminary Study

AIM AND OBJECTIVE

The aim of the study was to evaluate the changes in free available chlorine (FAC) when 6% sodium hypochlorite (NaOCl) is admixed with irrigants 17% ethylenediaminetetraacetic acid (EDTA), 2% chlorhexidine (CHX), and 0.2% chitosan in varying proportions of 90:10, 80:20, and 50:50.

MATERIALS AND METHODS

The 25 mL aliquots of 6% NaOCl were admixed in varying proportions of 90:10, 80:20, and 50:50 with secondary irrigation solutions: (a) 17% EDTA, (b) 2% CHX, (c) 0.2% chitosan. Iodometric titration was done to evaluate the change in FAC.

STATISTICAL ANALYSIS USED

Kruskal-Wallis and Mann-Whitney tests.

RESULTS

On titration, the mean FAC value of NaOCl at baseline was 1.99 g%. On mixing NaOCl with EDTA, the FAC decreased in all the three proportions and the values were 0.17 g%, 0.17 g%, and 0.06 g% at 90:10, 80:20, and 50:50 ratios, respectively. pH obtained was 9.55 at 50:50 ratio. On mixing NaOCl with CHX, FAC reduced and the values were 1.84 g%, 1.72 g%, and 0.27 g% at 90:10, 80:20, and 50:50 ratios, respectively. pH obtained was 10.87 at 50:50 ratio. On mixing NaOCl and chitosan, the FAC remained unaltered in all the three proportions and the values were 1.64 g%, 1.51 g%, and 1.63 g% at 90:10, 80:20, and 50:50 ratios, respectively. pH obtained was 11 at 50:50 ratio.

CONCLUSION

Combination of NaOCl and chitosan did not lead to a reduction in FAC and the pH of the solution remained unaltered, suggesting that tissue-dissolving property of NaOCl might be preserved.

CLINICAL SIGNIFICANCE

The combination of chitosan with NaOCl is advantageous in two ways. Firstly, FAC remained unaltered and the pH of the solution was also maintained at 11.05 indicating that the tissue-dissolving property of NaOCl prevailed. Secondly, chitosan is known for its chelating property and is effective in smear layer removal. With further in vivo and in vitro studies, a combination of chitosan and NaOCl can be proposed as a novel irrigant.

EDTA, oxalate, and phosphate ions enhanced reactive oxygen species generation and sulfamethazine removal by zero-valent iron

The activation rate of oxygen by zero-valent iron (Fe°) was very low. In this study, ethylenediaminetetraacetic acid (EDTA), oxalate (Ox), and phosphate ions (Na₂HPO₄) were used to enhance the oxygen activation by Fe° for sulfamethazine (SMT) removal. The addition of these ligands could significantly enhance the SMT degradation. SMT removal was improved from 10.5 % in the Fe° system (360 min) to 70.3 %, 85.2 % and 77.8 % in the Fe°/EDTA (60 min), Fe°/Ox (180 min) and Fe°/phosphate (360 min) systems, respectively. Scanning electron microscopy with energy dispersive X-ray (SEM-EDX), Fourier transform infrared reflection (FTIR), contact angle and X-ray photoelectron spectra (XPS) of Fe° in different systems were recorded. The presence of chelating agents hydroxylated Fe°, inhibited the iron oxide formation on the Fe° surface and promoted iron ion release from the solid. Moreover, the agents improved the recovery of surface Fe²⁺ which could subsequently enhance the activation of O₂ to produce more H₂O₂ and reactive oxygen radicals for SMT removal. OH radical produced mainly through H₂O₂ decomposition was primarily responsible for removing SMT in all three systems. The Fe° system added with chelating agents is a new and promising approach for treating wastewaters containing ligands.

Cadmium phytoextraction from contaminated paddy soil as influenced by EDTA and Si fertilizer

The efficiency of heavy metal (HM) phytoextraction from contaminated soil directly depends on the pollutant bioavailability, which can be increased by some soil amendments. In field test, the impacts of soil-applied ethylenediaminetetraacetic acid (EDTA) and amorphous silicon dioxide (ASD) and foliar-applied monosilicic acid (MS) on cadmium (Cd) uptake by rice plants from contaminated paddy soil were investigated. Without EDTA, the solid or liquid Si materials reduced the Cd accumulation in the aboveground part of rice by 26 to 52%. If EDTA was applied, the Cd accumulation by plants was increased by 60 to 92%; however, the biomass was reduced by 16 to 35%. The combined application of Si-rich materials and EDTA provided enhanced plant tolerance to a negative influence of EDTA, while kept high Cd content in the rice stems and leaves. As a result, the Cd amounts extracted by the stems and leaves from the unit area of contaminated paddy soil were greater by 25 and 37% in comparison with those for only EDTA treatment.

Analysis of Post-Sample Collection EDTA Effects on Mean Platelet Volume Values in Relation to Overweight and Obese Patient Status

BACKGROUND

Mean platelet volume (MPV) may be a useful biomarker for platelet activation in obese patients. However, storage duration and use of anticoagulant K3-ethylenediaminetetraacetic acid (EDTA) may interfere with these measurements.

OBJECTIVES

The aim of this study was to measure the variability of MPV in obese patients following exposure to EDTA.

METHOD

A total of 160 patients were divided into 3 groups according to body mass index (BMI; normal: <25 kg/m2; overweight: 25-30 kg/m2; obese: >30 kg/m2). Blood was collected in sterile tubes containing K3-EDTA. Blood cell counts were obtained using the CELL-DYN Ruby system immediately and 1, 2, and 3 h after collection.

RESULTS

MPV was found to be directly proportional to BMI. With the addition of EDTA, MPV was increased in the first hour after collection; MPV then decreased to levels that were lower than initial baseline measurements.

CONCLUSIONS

K3-EDTA use alters platelet volume. The time from collection to measurement should be standardized to reduce MPV value variance. MPV should be determined within 1 h of collection to avoid anticoagulant use-related interference.

Collection of cerebrospinal fluid into EDTA versus plain tubes does not affect the standard analysis in dogs

BACKGROUND

Cerebrospinal fluid (CSF) can be collected into ethylenediaminetetraacetic acid (EDTA) or plain tubes. The EDTA content presumably contributes to a better cell preservation. EDTA, however, is reported to cause a false elevation in the total protein concentration and to dilute the CSF sample, thereby affecting the diagnostic interpretation. To the authors' knowledge, no validated studies support this view. The aim of this study was therefore to determine if the choice of tube (EDTA or plain) influences the results of the standard CSF analysis.

RESULTS

Thirty-two paired EDTA stabilised and plain CSF samples were included. There was no statistically significant difference in the semi-quantitative protein concentrations when comparing CSF samples from EDTA and plain plastic tubes (P > 0.99). The total nucleated cell count did not differ significantly between EDTA and plain tube samples (P = 0.85). There were no significant differences in the differential cell counts between the two tubes when evaluating polymorphonuclear cells (P = 0.90), lymphocytes (P = 0.84) and monocytes/macrophages (P = 0.86). Also, there was no significant difference in the preservation of cell morphology when evaluating cytological preparations from EDTA stabilised and plain tube samples (P = 0.45).

CONCLUSIONS

The collection of CSF into EDTA tubes does not influence the result of the standard CSF analysis. However, a presumed positive effect of EDTA on cell preservation could not be shown in the present study.

Accidental injection of ethylenediaminetetraacetic acid (EDTA) instead of an anaesthetic solution: a case report

The accidental use of drugs is an unacceptable mistake in medicine, but the misuse of different agents has been reported frequently in the literature. While performing local anesthesia before starting dental treatment, the injection of a wrong agent, as a result of confusing the liquid in the syringe may cause local and systemic complications. Sudden swelling, intense pain, and severe allergic reactions may develop in the patient. A complication causing soft tissue necrosis is presented in this case report in which Ethylenediaminetetraacetic acid (EDTA) was accidentally injected instead of an anesthetic solution. This case report is unique because it is the first to report an inadvertent injection of EDTA in dentistry.

Time-Dependent Effect of Various Irrigants for Root Canal on Smear Layer Removal

Background:

Existence of smear layer in root canals caused by instrumentation is believed to prevent penetration of irrigating agents, thereby resulting in endodontic treatment.

Aims and Objectives:

To compare and evaluate the effectiveness of two irrigants: 17% ethylenediaminetetraacetic acid (EDTA) and mixture of tetracycline isomer, an acid, and a detergent (MTAD) as final agents for eliminating the smear layer.

Materials and Methods:

We included 50 human lower premolar teeth whose crowns were sectioned at cementoenamel junction. The sample was randomly grouped into five groups, each with 10 teeth. Group 1: 1 mL of 17% EDTA as final rinse for 1 min, Group 2: 1 mL of 17% EDTA for 30 s, Group 3: 5 mL of MTAD for 2.5 min, Group 4: 5 mL of MTAD for 5 min, and Group 5: saline. The specimens were sectioned vertically all along the long axis and fixed on an aluminum stub for gold ion sputtering. Scanning electron microscope was used to observe the specimens, and photomicrographs were taken at coronal, middle, and apical thirds of canal, and assessed by Torabinejad scoring system by two examiners, and the observations were analyzed statistically.

Results:

When Group 1 and Group 2 and Groups 3 and 4 were compared, we found a significant variation in removal of smear layer at cervical and middle thirds, and insignificant difference at apical third. In comparison with EDTA and saline, MTAD was more efficient significantly in middle and cervical thirds and insignificant at apical third.

Conclusion:

MTAD is an efficient irrigant for removing smear layer than EDTA and saline.

Smear Layer Removing Ability of Root Canal Irrigation Solutions: A Review

AIM

The purpose of this review is to address the smear layer removing the ability of root different canal irrigants including ethylenediaminetetraacetic acid (EDTA), a mixture of tetracycline, acid and detergent (MTAD), tetraclean, citric acid, Q-Mix, maleic acid, and smear clear.

BACKGROUND

Smear layer is a layer which is produced during instrumentation. It contains both organic and inorganic materials. It may also contain bacteria and their byproduct considering the root canal situation. This layer may prevent the penetration of the healing material introduced to the canal to the interior of the dentinal tubules. In addition, it can affect the adaptation of sealing materials to the root canal walls.

REVIEW RESULTS

The smear layer removal ability of MTAD is superior and faster than EDTA. Tetraclean is similarly composed of an acid, an antibiotic, and a detergent. The presence of doxycycline is believed to help the smear layer removal ability of these irrigants. Antibiotics such as tetracycline had similar smear layer removal ability as even citric acid. EDTA is an amino acid with a chelating ability that sequestrates metal ions. Some believed EDTA smear layer removing ability is better than MTAD, tetraclean, SmearClear, and 20% citric acid which is controversial in case of comparison between MTAD and EDTA. Phosphoric acid is efficient enough to be comparable to EDTA in removing the smear layer. Maleic acid is an organic compound with acid etching smear layer removal. Its ability seems to be similar or even better than EDTA. Citric acid as another organic acid is believed to be used as smear removing agent. HEBP is another chelating agent that can be used in combination with NaOCl; however, HEBP is a weak decalcifying agent compared to EDTA and hence cannot be applied as a mere final rinse. QMiX is a combination of CHX, EDTA, and detergent and should be used at final rinse. It is believed that QMiX is as efficient as EDTA. Smear clear is a 17% EDTA solution including an anionic and cationic (cetrimide) surfactant. The ability of QMiX is similar to EDTA.

CONCLUSION

There are different canal irrigation solutions with various smear layer removal ability that some should be used as a mere final rinse and some should not.

CLINICAL SIGNIFICANCE

The usage of canal irrigation solutions depends on the clinical situation and preference of the dentists. This study provides a good guide for clinician of the field.

Role of EDTA on the Pd(II) adsorption characteristics of chitosan cross-linked 3-amino-1,2,4-triazole-5-thiol derivative from synthetic electroless plating solutions

This article targets the efficacy of chitosan cross-linked 3-Amino-1,2,4-triazole-5-thiol derivative for the recovery of Pd from synthetic electroless plating solutions (ELP) whose solution chemistry complexity is brought forward with ethylenediaminetetraacetic acid (EDTA), ammonium hydroxide (NH₄OH), and surfactant (cetyl trimethyl ammonium bromide (CTAB)). Batch adsorption characteristics of the resin were investigated in the parametric range of 2-10 pH, 0.2-2 g L^-1 adsorbent dosage, 5-1080 min contact time, 50-300 mg L^-1 Pd concentration and 25-60 °C operating temperature. Equilibrium, kinetic and thermodynamic model fitness studies were also considered. Pd(II) adsorption characteristics were determined using NaOH, KOH and HCl solutions with variant eluent concentrations (0.1-2 N). The solution chemistry complexity has been evaluated to have profound impact in detrimentally influencing Pd sorption characteristics of the CH-AZ resin. The resin has been characterized to be highly effective for Pd removal from synthetic ELP solutions but with moderate efficacy towards the noble metal recovery and reuse.

Comparative Evaluation of Cleaning Efficacy of Self-adjusting File and WaveOne File: An in vitro Scanning Electron Microscopic Study

AIM

This study aims to compare the cleaning efficacy of root canal walls using two rotary single file systems: self-adjusting file (SAF) and WaveOne (WO).

MATERIALS AND METHODS

Forty extracted human premolars with similar range of canal curvature were selected, decoronated, working length determined and roots were divided into two groups of 20 samples each: Group I - SAF and Group II - WO. All root canals were irrigated with 3% sodium hypochlorite (NaOCl) and 17% ethylenediaminetetraacetic acid (EDTA). The roots were sectioned longitudinally and subjected to scanning electron microscopic examination. The amount of debris and smear layer was evaluated using five score index at coronal, middle and apical third levels. Statistical analysis was performed using the Chi-square test and significance was set at a P < 0.05.

RESULTS

Statistically significant difference was observed between the groups in cleaning the apical third. Group I (SAF) showed better canal cleanliness compared to Group II (WO) in the apical third.

CONCLUSION

Within the limitations of this study, SAF in combination with 3% NaOCl and 17% EDTA irrigating solution had significantly better cleaning efficacy in the apical third of root canals when compared to WO rotary file system.

Evaluation of Influence of Widening Apical Preparation of Root Canals on Efficiency of Ethylenediaminetetraacetic Acid Agitation Protocols: Study by Scanning Electron Microscopy

AIM

The purpose of this study was to evaluate the influence of widening the apical root canal preparation (RCP) on the efficiency of different ethylenediaminetetraacetic acid (EDTA) agitation protocols on smear layer removal: EDTA; EDTA + Easy Clean in rotary movement (ECROT); EDTA + Easy Clean in reciprocating movement (ECREC); and EDTA + Passive ultrasonic irrigation (PUI).

MATERIALS AND METHODS

A total of 80 mandibular premolars had their crowns sectioned and then were divided into two groups according to widening: size 25 or 40, 0.08 taper. Sequentially they were once again allocated to subgroups according to the agitation protocol performing eight experimental groups (n = 10). Ten additional teeth were prepared for controls (C+/C-). The specimens were then submitted to the cleaning protocols and thereafter cleaved and microphotographed by variable pressure scanning electron microscopy (SEM) at previously determined points along their root thirds (750*). Scores were attributed to the images, and data were analyzed by the Kruskal-Wallis, Student-Newman-Keuls and Friedman tests.

RESULTS

A higher widening was observed to have a positive influence on cleaning efficiency offering significant differences in global and apical third evaluations (p < 0.05). Relative to the agitation, significant differences were observed mainly in the apical third, with PUI and ECROT providing the best results (p < 0.05); no difference for C+ was observed when higher widening was employed.

CONCLUSION

A greater widening of the apical third provided a significant improvement in the action of the agitation/activation protocols. Moreover, the PUI and ECROT activation methods were shown to be superior to the use of EDTA solely, particularly in the apical third.

CLINICAL SIGNIFICANCE

The findings of this study reinforce the need for clinical use of additional methods to complement cleaning. Therefore, it is important for professionals to have knowledge and command of these protocols to obtain more satisfactory results.

A comparative evaluation of shear bond strength of composite resin to pulp chamber dentin treated with sodium thiosulfate and proanthocyanidin: An in vitro study

Aim:

Based on the importance of coronal sealing right after endodontic treatment, this in vitro study aimed to evaluate the difference of shear bond strength to pulp chamber dentin treated with sodium thiosulfate and proanthocyanidin (PA).

Materials and Methods:

Fifteen extracted mandibular molar teeth were decoronated at the level of cementoenamel junction horizontally. The individual teeth were then sectioned mesiodistally to expose the pulp chamber dentin using a diamond disc. The specimens were randomly divided into three groups (n = 10). Group A: control group, treated with 5.25% sodium hypochlorite (NaOCl) for 30 min followed by a final rinse with 17% ethylenediaminetetraacetic acid (EDTA) solution for 3 min; Group B: after pretreatment with NaOCl and EDTA, it is further treated with 5% sodium thiosulfate (Na₂S₂O₃) for 10 min; and Group C: after pretreatment with NaOCl and EDTA, it is further treated with 6.5% PA for 10 min. After drying the specimens, a bonding agent namely One Coat Bond SL (SwissTEC, Coltene) was applied to the pulp chamber dentin followed by a composite restoration (SwissTEC, Coltene). Each specimen was then tested under a universal testing machine at the dentin/resin interface to determine the shear bond strength.

Results:

Both the groups in which 5% Na₂S₂O₃ and 6.5% PA were used for 10 min showed bond strength that was found to be statistically higher than the positive control (P < 0.05).

Conclusion:

The use of Na₂S₂O₃ and PA can significantly increase the bond strength of composite resin to NaOCl/EDTA-treated dentin, allowing adhesive restorations to be immediately applied after endodontic treatment.

Root canal irrigants influence the hydrophobicity and adherence of Staphylococcus epidermidis to root canal dentin: an in vitro study

Objectives

To determine the effect of root canal irrigants on the hydrophobicity and adherence of Staphylococcus epidermidis (S. epidermidis) to root canal dentin in vitro.

Materials and Methods

Root dentin blocks (n = 60) were randomly divided into 4 groups based on the irrigation regimen: group 1, saline; group 2, 5.25% sodium hypochlorite (NaOCl); group 3, 5.25% NaOCl followed by 17% ethylenediaminetetraacetic acid (EDTA); group 4, same as group 3 followed by 2% chlorhexidine (CHX). The hydrophobicity of S. epidermidis to root dentin was calculated by cell surface hydrophobicity while the adherence was observed by fluorescence microscopy, and bacteria were quantified using ImageJ software (National Institutes of Health). Statistical analysis of the data was done using Kruskal-Wallis test and Mann-Whitney U test (p = 0.05).

Results

The hydrophobicity and adherence of S. epidermidis to dentin were significantly increased after irrigating with group 3 (NaOCl-EDTA) (p < 0.05), whereas in group 4 (NaOCl-EDTA-CHX) both hydrophobicity and adherence were significantly reduced (p < 0.05).

Conclusions

The adherence of S. epidermidis to dentin was influenced differently by root canal irrigants. Final irrigation with CHX reduces the bacterial adherence and may impact biofilm formation.

Risks of using EDTA as an agent for trace metals dosing in anaerobic digestion of olive mill solid waste

Low concentrations of trace elements in many organic wastes recommend their supplementation in order to avoid potential limitations. Different chelating agents have been used to ensure an adequate trace metal pool in the soluble fraction, by forming dissolved complexes. Ethylenediaminetetraacetic acid (EDTA) is probably the most common, although several negative effects could be associated with its usage. Biomethane potential tests were performed using Olive Mill Solid Waste as the substrate, supplementing different combinations of Fe, Co, Ni, Ba, always under the presence of EDTA. Results show that Ni and Co slightly recovered biodegradability. However, Ba supplementation resulted in worsening the methane yield coefficient in all cases. High concentration of EDTA led to decrease in the activity of anaerobic digestion. High availability of EDTA induces the capture of trace metals like Co or Ni, key trace metals for anaerobic biomass activity. While supplementing trace metals, the addition of Ba and/or EDTA must be carefully considered.

Effects of smear layer removal agents on the physical properties and microstructure of mineral trioxide aggregate cement

OBJECTIVE

To compare the effect of QMix (Dentsply Sirona), 7% maleic acid (MA), and 17% ethylenediaminetetraacetic acid (EDTA) on the microhardness, flexural strength and microstructure of mineral trioxide aggregate (MTA; ProRoot MTA, Dentsply Sirona).

METHODS

Forty MTA specimens were divided into four groups: [I] QMix [II] 7% MA [III] 17% EDTA and [IV] distilled water (control). After treatment with 5mL of the respective solution for 1min, the specimens were tested for microhardness using a Knoop hardness tester. Forty additional specimens were similarly treated and evaluated for the flexural strength using a universal testing machine. For microstructure evaluation, MTA specimens were treated in a similar manner and examined by X-ray diffractometry and scanning electron microscopy (SEM).

RESULTS

For microhardness, there were no differences between distilled water, QMix and EDTA groups. However, MTA exposed to distilled water had higher microhardness than MA. When compared with QMix and EDTA, MA had lower microhardness; there was no difference between EDTA and QMix. For flexural strength, distilled water group had higher flexural strength than the other agents. There were no differences between EDTA vs MA and EDTA vs QMix. Specimens treated with QMix had higher flexural strength than MA. X-ray diffraction indicated that EDTA inhibited hydration of MTA. For SEM, all the tested agents altered the microstructure of MTA when compared to distilled water.

CONCLUSION

MA had more detrimental effect on the physical properties of MTA and EDTA was more detrimental to the hydration of MTA.

CLINICAL SIGNIFICANCE

The present study highlights the effect of newer chelating agents on the physical properties and microstructure of MTA. Preventing the deterioration of MTA is important for its long term success in endodontic procedures.

In Vitro Leukoagglutination: A Rare Hematological Cause of Spurious Leukopenia

Leukopenia secondary to leukocytic agglutination is caused by an ethylene diamine tetra acetic acid (EDTA) which may appear in both benign and malignant states. Ethylene diamine tetra acetic acid induced platelets clumping in peripheral blood has been well established, but invitro leukocytic aggregation is very rarest hematological finding. Pseudo-leukopenia resulting from leukoagglutinins has been reported in the cirrhotic state, infections, autoimmune disorders, uremia, in immunosuppressed state or in various malignancies. Though the condition seems to be benign but very important to be detected as these artifactual findings lead to unnecessary investigations and remarkably changed the overall management plan. Here we report the case of a young patient with this rare finding who was admitted to our hospital with progressive labor pains. The analysis of ethylene diaminetetraacetic acid (EDTA), anticoagulated blood was done on automated hematology analyzer reveals leukopenia. The peripheral smear examination revealed multiple aggregates of leukocytes. On repeat sampling in citrate anticoagulant, the complete blood count showed total leukocytic count of 16.5x109/L with absolute neutrophilic count of 11.5x109/L. This is a rare case of spurious leukopenia secondary to in-vitro leukocytic agglutination provoked by EDTA anticoagulant.

A comparative evaluation of the effect of 8% and 17% ethylenediaminetetraacetic acid exposure for 1 min and 10 min on the fracture resistance of endodontically treated roots: An in vitro study

Objective:

The objective of this study was to evaluate the effect of 8% and 17% ethylenediaminetetraacetic acid (EDTA) exposure for 1 min and 10 min on the fracture resistance of endodontically treated roots.

Methodology:

Sixty human single-rooted teeth were decoronated and divided into six groups (n = 10). Canal preparation was carried out except in negative control group, using the ProTaper rotary file system. Final irrigation was performed using distilled water, 17% EDTA for 1 min and 10 min, 8% EDTA for 1 min and 10 min. Thereafter, roots were obturated with ProTaper F3 Gutta-percha points and AH Plus sealer using a single-cone technique. The specimens were loaded vertically at 1 mm/min crosshead speed until vertical root fracture occurred. Results were evaluated statistically with one-way analysis of variance and post hoc Tukey test.

Results:

Analysis of results showed that the unprepared roots showed the highest fracture resistance and roots irrigated with 17% EDTA for 10 min showed the lowest fracture resistance. The mean fracture resistance of unprepared roots, roots irrigated with 8% EDTA for 10 min and 17% EDTA for 1 min was significantly higher than roots irrigated with 8% EDTA for 1 min, 17% EDTA for 10 min and distilled water.

Conclusion:

From a clinical viewpoint, if EDTA has to be used, it is safer to use higher concentration for a shorter application time or a low concentration with a longer application time. Prolonged use of high concentrations of EDTA might increase the risk of root fracture.

Identification of the immunogenic epitopes of the whole venom component of the Hemiscorpius lepturus scorpion using the phage display peptide library

The venom of the Hemiscorpius lepturus scorpion contains mixtures of bioactive compounds that disturb biochemical and physiological functions of the victims. Hemiscorpius lepturus envenomation is recognized as a serious health concern in tropical regions. So far, there is no preventive procedure, and the main focus is on treatment of victims with an antiserum purified from hyper-immunized horses. Although antisera can neutralize the venom, they, in some cases, lead to anaphylactic shock and even death. Selection of peptides mimicking antigenic and immunogenic epitopes of toxins from random peptide libraries is a novel approach for the development of recombinant toxins and poly-epitopic vaccine. To achieve this aim, a phage display peptide library and three rounds of biopanning were performed on immobilized antibodies (IgGs) purified from the sera of hyper-immunized horses. The results show that the highest binding of the phage to immobilized horse antibodies occurred in the third round of biopanning. Over 125 individual clones carrying mimotopes of Hemiscorpius lepturus toxins were selected and subjected for sequencing. The sequencing results identified unique peptides mimicking the antigenic and immunogenic epitopes of Hemiscorpius lepturus toxins. The results of this study provide a basis for further studies and the development of a putative epitopic vaccine and a recombinant toxin.

Evaluating the Effect of CPP-ACP as a Final Irrigant in Improving the Micro-Hardness of Erosive Root Dentin and its Influence on the Bond Strength of Self Etch Resin Sealer - An In-vitro Study

INTRODUCTION

Smear layer removal from the root canal wall involves the use of 17% EDTA and 5.25% sodium hypochlorite, which thereby improves the adhesion of obturating materials to root dentin. But these chemical irrigants have shown to decrease micro hardness, increase roughness, cause erosion and reduce the root dentin fracture toughness. To combat these adverse effects, studies can be focussed on the remineralisation of the erosive root dentin and this novel idea has been utilized in the present study.

AIM

To evaluate the micro hardness of erosive root dentin when Casein Phosphopeptide-Amorphous Calcium Phosphate (CPP-ACP) was used as a final irrigant and its influence on resin sealer bonding tested by push-out bond strength method.

MATERIALS AND METHODS

Sixty extracted maxillary incisors were divided into three groups based on the final irrigation protocol. Group 1-normal saline, Group 2-17% EDTA (Ethylene Diamine Tetraacetic Acid) + 5.25% NaOCl (Sodium Hypochlorite), Group 3 - 17% EDTA + 5.25% NaOCl + CPP-ACP; each group was divided into two subgroups. Half the specimens of each group were evaluated for Vicker's micro hardness test after the treatment. In continuation with the above methodology the remaining specimens were tested for push-out bond strength after obturation of the specimens with self etch adhesive resin sealer and conventional 6% gutta percha cones.

RESULTS

Micro hardness was statistically analysed using Kruskal Wallis test and push-out bond strength was evaluated using Mann Whitney test and paired t-test. CPP-ACP treated group showed increased micro hardness (p<0.05). There was no statistically significant difference between the push-out bond strength values between group EDTA + NaOCl group and EDTA + NaOCl + CPP-ACP group.

CONCLUSION

Within the limitations of this study it can be concluded that, CPP-ACP improved the micro hardness of erosive root dentin and is not affecting its bond strength. Therefore, CPP-ACP may be used before bonding procedures for promoting remineralization of root dentin.

Impact of Various Irrigating Agents on Root Fracture: An in vitro Study

INTRODUCTION

Irrigating solutions are used for cleaning and removing dentinal debris, and the other remains from pulpal space during biomechanical preparation. Therefore, we evaluated the impact of various irrigating agents on root fracture at 5-minute time exposure.

MATERIALS AND METHODS

We sectioned 60 permanent maxillary premolars with fully formed root structures transversely maintaining the root length of approximately 14 mm. Five study groups were made comprising ethylenediaminetetraacetic acid (EDTA), cetrimide, citric acid, and so on as various irrigating agents. A universal force test machine was used to calculate the force which was enough to fracture each root. Analysis of variance (ANOVA) test was used to access the level of significance.

RESULTS

About 10% citric acid solution as an irrigating agent showed minimal fracture opposing results, whereas 10% EDTA solution showed the maximum fracture resistance of root portion.

CLINICAL SIGNIFICANCE

Selection of suitable EDTA concentration that has minimal adverse effect on the mechanical properties of the tooth is very important for the successful management of tooth fracture.

CONCLUSION

About 10% EDTA provided the highest fracture resistance, necessitating the use of irrigating solution in root canal therapy (RCT). Further research with higher and different study groups is required to search for more efficient irrigating solution to improve the outcome of RCT.

Effect of combination of ethylenediaminetetraacetic acid + tetracycline with coronally positioned flap in the treatment of gingival recession: A clinical study

CONTEXT

Gingival recession is the apical migration of gingival margin results from destruction of the connective tissue leading to various esthetic problems. Many surgical procedures have been attempted to achieve root coverage that include free gingival grafts, pedicle flaps such as semilunar coronally repositioned flaps (SCRFs) and guided tissue regeneration. The exposed root surface has undergone substantial alterations and may no longer serve as an appropriate substrate for cell attachment and fiber development. When the denuded root surfaces are treated with biomodifiers following mechanical instrumentation, the resulting surface favors both the attachment of fibroblasts and new connective tissue attachment. It was then necessary to evaluate the surface characteristics of the acid demineralized root surface and its effect on periodontal wound healing.

AIM

To evaluate the effect of the combination of ethylenediaminetetraacetic acid (EDTA) and tetracycline as root bio-modifiers along with SCRF for root coverage.

SETTINGS AND DESIGN

Twenty subjects were randomly assigned into two groups as cases (SCRF + EDTA + tetracycline [TTC]) and controls (SCRF).

MATERIALS AND METHODS

Twenty-four percentage EDTA and 100 mg/ml TTC hydrochloride were used along with semilunar coronally positioned flap. The clinical parameters such as recession height, the width of keratinized tissue, recession width, clinical attachment level, probing depth, plaque index, and gingival index were recorded at baseline, 1 and 3 months.

STATISTICAL ANALYSES USED

The clinical parameters were compared using post-hoc test and the comparison between cases and controls was done using Mann-Whitney U-test.

RESULTS

No statistical significant difference has been observed between the groups.

CONCLUSION

It was concluded that no clinical benefit was observed after the application of a combination of 100 mg/ml TTC hydrochloride and 24% EDTA on the root surface.

Effect of irrigating solutions used for postspace treatment on the push-out bond strength of glass fiber posts

Aim:

To evaluate the effect of different irrigating solutions on postspace treatments on the push-out bond strength of glass fiber posts.

Materials and Methods:

Thirty mandibular premolar roots were decoronated and endodontically treated. Postspaces were prepared and roots were divided into three groups: In group 1: 2.5% sodium hypochlorite irrigation (control), group 2: 17% ethylenediaminetetraacetic acid (EDTA) with hand activation, group 3: 17% EDTA irrigation with photon-induced photoacoustic streaming (PIPS) has been done to the postspaces. Scanning electron microscope (SEM) analysis has been made for two samples of each group. Fiber posts were then luted with resin cement. Each root was prepared for push-out test. Data have been statistically analyzed.

Results:

SEM results showed clean postwalls with both group 2 and group 3, whereas group 1 showed adhesion of resin cement to intraradicular dentine. When all groups were compared, the bond strength values are higher with group 2 followed by group 3.

Conclusion:

Within the limitations of the study, clean postwalls and the highest bond strength values were obtained from 17% EDTA with hand activation and 17% EDTA with PIPS.

Regenerative potential of immature permanent non-vital teeth following different dentin surface treatments

This study evaluates the regenerative potential of immature permanent non-vital teeth following different dentin surface treatments in dogs. Periapical lesions and necrotic pulps were induced in 288 roots of 144 teeth in twelve dogs. Teeth were randomly divided into 3 equal groups according to the evaluation period. Each group was subdivided into 8 subgroups according to the treatment modalities including; blood clot, blood clot and collagen, blood clot and Ethylenediaminetetraacetic acid (EDTA), blood clot, collagen and EDTA, blood clot and Mixture Tetracycline Citric Acid and Detergent (MTAD), blood clot, collagen and MTAD, positive control and negative control. Apart from control subgroups, all infected root canals were cleaned with sodium hypochlorite solution and triple antibiotics paste before different treatment protocols. After different treatments, the root length, thickness and apical diameter were evaluated by radiographic examination. Histopathological examination was carried out to evaluate the inflammation, bone/root resorption, tissue in-growth in pulp space, new hard tissue formation and apical closure. Using EDTA solution as a surface modifier showed significantly higher levels of tissue in-growth in the pulp space after 6 weeks and 3 months. Addition of collagen as a scaffold caused significantly more bone/root resorption than the other subgroups while EDTA caused significantly lower inflammatory cell counts only after 2 weeks. Final rinse with 17% EDTA solution before blood clot induction has positive impact on tissue interaction along dentinal walls without modification of the cell type. Moreover, the use of collagen as a scaffold material and MTAD as a surface modifier did not improve the quality of the regenerative process.

Selective extraction and release using (EDTA-Ni)-layered double hydroxide coupled with catalytic oxidation of 3,3',5,5'-tetramethylbenzidine for sensitive detection of copper ion

Copper is an important heavy metal in various biological processes. Many methods have been developed for detecting of copper ions (Cu(2+)) in aqueous samples. However, an easy, cheap, selective and sensitive method is still desired. In this study, a selective extraction-release-catalysis approach has been developed for sensitive detection of copper ion. Ethylenediaminetetraacetic acid (EDTA) chelated with nickel ion (Ni(2+)) were intercalated in a layered double hydroxide via a co-precipitation reaction. The product was subsequently applied as sorbent in dispersive solid-phase extraction for the enrichment of Cu(2+) at pH 6. Since Cu(2+) has a stronger complex formation constant with EDTA, Ni(2+) exchanged with Cu(2+) selectively. The resulting sorbent containing Cu(2+) was transferred to catalyze the 3,3',5,5'-tetramethylbenzidine oxidation reaction, since Cu(2+) could be released by the sorbent effectively and has high catalytic ability for the reaction. Blue light emitted from the oxidation product was measured by ultraviolet-visible spectrophotometry for the determination of Cu(2+). The extraction temperature, extraction time, and catalysis time were optimized. The results showed that this method provided a low limit of detection of 10nM, a wide linear range (0.05-100μM) and good linearity (r(2)=0.9977). The optimized conditions were applied to environmental water samples. Using Cu(2+) as an example, this work provided a new and interesting approach for the convenient and efficient detection of metal cations in aqueous samples.

Endocrine disrupting alkylphenolic chemicals and other contaminants in wastewater treatment plant effluents, urban streams, and fish in the Great Lakes and Upper Mississippi River Regions

Urban streams are an integral part of the municipal water cycle and provide a point of discharge for wastewater treatment plant (WWTP) effluents, allowing additional attenuation through dilution and transformation processes, as well as a conduit for transporting contaminants to downstream water supplies. Domestic and commercial activities dispose of wastes down-the-drain, resulting in wastewater containing complex chemical mixtures that are only partially removed during treatment. A key issue associated with WWTP effluent discharge into streams is the potential to cause endocrine disruption in fish. This study provides a long-term (1999-2009) evaluation of the occurrence of alkylphenolic endocrine disrupting chemicals (EDCs) and other contaminants discharged from WWTPs into streams in the Great Lakes and Upper Mississippi River Regions (Indiana, Illinois, Michigan, Minnesota, and Ohio). The Greater Metropolitan Chicago Area Waterways, Illinois, were evaluated to determine contaminant concentrations in the major WWTP effluents and receiving streams, and assess the behavior of EDCs from their sources within the sewer collection system, through the major treatment unit processes at a WWTP, to their persistence and transport in the receiving stream. Water samples were analyzed for alkylphenolic EDCs and other contaminants, including 4-nonylphenol (NP), 4-nonylphenolpolyethoxylates (NPEO), 4-nonylphenolethoxycarboxylic acids (NPEC), 4-tert-octylphenol (OP), 4-tert-octylphenolpolyethoxylates (OPEO), bisphenol A, triclosan, ethylenediaminetetraacetic acid (EDTA), and trace elements. All of the compounds were detected in all of the WWTP effluents, with EDTA and NPEC having the greatest concentrations. The compounds also were detected in the WWTP effluent dominated rivers. Multiple fish species were collected from river and lake sites and analyzed for NP, NPEO, NPEC, OP, and OPEO. Whole-body fish tissue analysis indicated widespread occurrence of alkylphenolic compounds, with the highest concentrations occurring in streams with the greatest WWTP effluent content. Biomarkers of endocrine disruption in the fish indicated long-term exposure to estrogenic chemicals in the wastewater impacted urban waterways.

Comparative evaluation of a new endodontic irrigant - mixture of a tetracycline isomer, an Acid, and a detergent to remove the intracanal smear layer: a scanning electron microscopic study

BACKGROUND

The most important and demanding aspect of endodontic therapy is considered to be cleaning and shaping. Irrigation is considered a vital adjunct to instrumentation of the root canal for canal debridement. Until date, there is no single solution that simultaneously removes the smear layer and disinfects the entire root canal system. Thus, this in vitro study was designed to evaluate the efficiency of a new irrigation solution mixture of a tetracycline isomer, an acid, and a detergent (MTAD) (BioPure, Dentsply) containing a mixture of tetracycline (doxycycline hydrochloride), an acid (citric acid) and a detergent (Tween 80) in comparison with normal saline, 5% NaOCl and 17% ethylenediaminetetraacetic acid (EDTA) to remove intracanal smear layer.

MATERIALS AND METHODS

A total of 60 single rooted teeth were irrigated with Saline (Group A), 5% NaOCl (Group B), 17% EDTA (Group C) and MTDA (Group D). The extent of removal of smear layer and erosion was assessed using scanning electron microscope.

RESULTS

Irrigation with 5% NaOCl and MTAD as a final flush produced the cleanest surface with all the dentinal tubules open. No conjugation or erosion of dentinal tubules was noted (P > 0.05).

CONCLUSION

MTAD flush was the most effective debridement regimen in all the three thirds of the canal showing its ability to reach the apex with no conjugation and erosion of dentinal tubules.

The effect of laterally positioned flap-revised technique and 24% ethylenediaminetetraacetic acid root conditioning on root coverage: A case report

Complete root coverage is considered the true goal of treatment of gingival recession defects because only complete coverage assures recovery from the hypersensitivity and esthetic defects associated with recession areas. Previous studies have shown that the laterally positioned flap (LPF) technique or root surface biomodification yields a higher percentage of complete root coverage upon gingival recession treatment. This article highlights the use of the laterally positioned pedicle flap-revised technique (LPFRT) as a modification of the LPF technique, along with 24% EDTA gel as a root surface biomodification agent, in the management of localized gingival recession defects. Clinical examination revealed a Miller class II recession defect on the buccal aspect of the lower right central incisor, as well as the presence of aberrant frenum pull adjacent to the recession defect. The LPFRT, together with 24% EDTA gel, was speculated to cover the gingival recession defect. The frenectomy, along with periosteal fenestration, was planned simultaneously with LPFRT. After 6 months of therapy, the clinical condition was stable with complete root coverage and satisfactory healing of the gingival tissues at both the donor and recipient sites with no signs of inflammation.

Assay for characterizing the recovery of vertebrate cells for adhesion measurements by single-cell force spectroscopy

Single-cell force spectroscopy (SCFS) is becoming a widely used method to quantify the adhesion of a living cell to a substrate, another cell or tissue. The high sensitivity of SCFS permits determining the contributions of individual cell adhesion molecules (CAMs) to the adhesion force of an entire cell. However, to prepare adherent cells for SCFS, they must first be detached from tissue-culture flasks or plates. EDTA and trypsin are often applied for this purpose. Because cellular properties can be affected by this treatment, cells need to recover before being further characterized by SCFS. Here we introduce atomic force microscopy (AFM)-based SCFS to measure the mechanical and adhesive properties of HeLa cells and mouse embryonic kidney fibroblasts while they are recovering after detachment from tissue-culture. We find that mechanical and adhesive properties of both cell lines recover quickly (<10 min) after detachment using EDTA, while trypsin-detached fibroblasts require >60 min to fully recover. Our assay introduced to characterize the recovery of mammalian cells after detachment can in future be used to estimate the recovery behavior of other adherent cell types.

An in vitro evaluation of passive ultrasonic agitation of different irrigants on smear layer removal after post space preparation: a scanning electron microscopic study

This study evaluated the removal of debris and smear layer after post space preparation using different irrigations and passive ultrasonic agitation. Sixty human premolars were decoronated and post space prepared after endodontic therapy. The samples were then randomly divided into three experimental groups (Groups A, B, C) and one control group (Group D) with fifteen samples in each group. Groups A and B samples were treated with 10 % citric acid and 17 % ethylenediamintetraacetic acid (EDTA), respectively and passive ultrasonic agitation was done, rinsed with sodium hypochlorite and finally flushed with saline. Group C samples were conditioned with 36 % phosphoric acid and then rinsed with saline. The control group was treated with 3 % sodium hypochlorite, passive ultrasonic agitation done and flushed with saline. The samples were sectioned and evaluated for debris and smear layer removal under scanning electron microscope. 10 % citric acid showed the best removal of smear layer when compared with 17 % EDTA and 36 % phosphoric acid, but was not statistically significant (p > 0.05). The difference in scoring for debris and smear layer removal in the coronal, middle and apical third of post space of experimental groups in comparison with control group was statistically significant (p < 0.001).

Comparative gene expression analysis of Dtg, a novel target gene of Dpp signaling pathway in the early Drosophila melanogaster embryo

In the early Drosophila melanogaster embryo, Dpp, a secreted molecule that belongs to the TGF-β superfamily of growth factors, activates a set of downstream genes to subdivide the dorsal region into amnioserosa and dorsal epidermis. Here, we examined the expression pattern and transcriptional regulation of Dtg, a new target gene of Dpp signaling pathway that is required for proper amnioserosa differentiation. We showed that the expression of Dtg was controlled by Dpp and characterized a 524-bp enhancer that mediated expression in the dorsal midline, as well as, in the differentiated amnioserosa in transgenic reporter embryos. This enhancer contained a highly conserved region of 48-bp in which bioinformatic predictions and in vitro assays identified three Mad binding motifs. Mutational analysis revealed that these three motifs were necessary for proper expression of a reporter gene in transgenic embryos, suggesting that short and highly conserved genomic sequences may be indicative of functional regulatory regions in D. melanogaster genes. Dtg orthologs were not detected in basal lineages of Dipterans, which unlike D. melanogaster develop two extra-embryonic membranes, amnion and serosa, nevertheless Dtg orthologs were identified in the transcriptome of Musca domestica, in which dorsal ectoderm patterning leads to the formation of a single extra-embryonic membrane. These results suggest that Dtg was recruited as a new component of the network that controls dorsal ectoderm patterning in the lineage leading to higher Cyclorrhaphan flies, such as D. melanogaster and M. domestica.

ALG1-CDG: a new case with early fatal outcome

Congenital disorders of glycosylation (CDG) are a growing group of inherited metabolic disorders where enzymatic defects in the formation or processing of glycolipids and/or glycoproteins lead to variety of different diseases. The deficiency of GDP-Man:GlcNAc2-PP-dolichol mannosyltransferase, encoded by the human ortholog of ALG1 from yeast, is known as ALG1-CDG (CDG-Ik). The phenotypical, molecular and biochemical analysis of a severely affected ALG1-CDG patient is the focus of this paper. The patient's main symptoms were feeding problems and diarrhea, profound hypoproteinemia with massive ascites, muscular hypertonia, seizures refractory to treatment, recurrent episodes of apnoea, cardiac and hepatic involvement and coagulation anomalies. Compound heterozygosity for the mutations c.1145T>C (M382T) and c.1312C>T (R438W) was detected in the patient's ALG1-coding sequence. In contrast to a previously reported speculation on R438W we confirmed both mutations as disease-causing in ALG1-CDG.

Characterization of the human mitochondrial thiamine pyrophosphate transporter SLC25A19 minimal promoter: a role for NF-Y in regulating basal transcription

Transcriptional regulation of expression of the human mitochondrial thiamine pyrophosphate transporter (the product of the SLC25A19 gene) is unknown. To understand this regulation, we cloned and characterized the 5'-regulatory region of the SLC25A19 gene (1,080 bp). The cloned fragment was found to possess promoter activity in transiently transfected human-derived liver HepG2 cells. 5'- and 3'-deletion analysis has identified the minimal region required for basal SLC25A19 promoter activity to be between -131 and +20 (using the distal transcriptional start site as +1). The minimal promoter lacks typical TATA motif and contains two inverted CCAAT boxes (binding sites for NF-Y transcriptional factor). By means of mutational analysis, the critical role of both the upstream and downstream CCAAT boxes in basal SLC25A19 promoter activity was established; however, each of these boxes alone was found to be unable to support promoter activity. EMSA and supershift EMSA (with the use of specific antibodies against NF-Y subunits) studies, as well as chromatin immunoprecipitation assay, demonstrated the binding of NF-Y to both CCAAT boxes in vitro and in vivo, respectively. The requirement for NF-Y in SLC25A19 promoter activity in vivo was directly confirmed by the use of a dominant negative NF-YA mutant in transiently transfected HepG2 cells. These studies report for the first time the characterization of the SLC25A19 promoter and demonstrate an essential role for NF-Y in its basal activity.

Vascular targeting to the SST2 receptor improves the therapeutic response to near-IR two-photon activated PDT for deep-tissue cancer treatment

BACKGROUND

Broader clinical acceptance of photodynamic therapy is currently hindered by (a) poor depth efficacy, and (b) predisposition towards establishment of an angiogenic environment during the treatment. Improved depth efficacy is being sought by exploiting the NIR tissue transparency window and by photo-activation using two-photon absorption (2PA). Here, we use two-photon activation of PDT sensitizers, untargeted and targeted to SST2 receptors or EGF receptors, to achieve deep tissue treatment.

METHODS

Human tumor lines, positive or negative for SST2r expression were used, as well as murine 3LL cells and bovine aortic endothelial cells. Expression of SST2 receptors on cancer cells and tumor vasculature was evaluated in vitro and frozen xenograft sections. PDT effects on tumor blood flow were followed using in vivo scanning after intravenous injection of FITC conjugated dextran 150K. Dependence of the PDT efficacy on the laser pulse duration was evaluated. Effectiveness of targeting to vascular SST2 receptors was compared to that of EGF receptors, or no targeting.

RESULTS

Tumor vasculature stained for SST2 receptors even in tumors from SST2 receptor negative cell lines, and SST2r targeted PDT led to tumor vascular shutdown. Stretching the pulse from ~120fs to ~3ps led to loss of the PDT efficacy especially at greater depth. PDT targeted to SST2 receptors was much more effective than untargeted PDT or PDT targeted to EGF receptors.

GENERAL SIGNIFICANCE

The use of octreotate to target SST2 receptors expressed on tumor vessels is an excellent approach to PDT with few recurrences and some long term cures.