Αλέξανδρος Γ. Σφακιανάκης: 01/07/19

Monday, January 7, 2019

Prodding Trump’s EPA to reexamine Endangerment

Use external pressure to overcome Administration inertia on reviewing Endangerment Finding William L. Kovacs Campaign rhetoric strongly suggested that the Trump Administration would redress the Obama Administration's insane attempts to regulate every aspect of society in a futile attempt to control nature and climate. President Trump withdrew from the Paris Accord, initiated repeal of the…

from Climate Change Skeptic Blogs via hj on Inoreader http://bit.ly/2LUD2Ij

Nuclear Medicine

Distribution of bone tracer uptake in symptomatic knees after ACL reconstruction compared to asymptomatic non-operated knees: a method for better differentiating patient-specific from disease-specific bone tracer uptake in SPECT/CT

Abstract

Objective

To evaluate the differences of bone tracer uptake (BTU) in symptomatic and asymptomatic contralateral knees in patients after reconstruction of the anterior cruciate ligament (ACL-R) and to identify typical BTU patterns and threshold values to differentiate pathological from physiological BTU.

Methods

53 patients after unilateral ACL-R were retrospectively included in the study. The population was subdivided into a group of symptomatic operated knees and a group of contralateral asymptomatic non-operated knees. BTU was measured in SPECT/CT using a validated anatomical localization-scheme and normalized mean BTU values were calculated in both knees. Wilcoxon signed rank-test and Pearson's rank-correlation coefficient were used (p < 0.05).

Results

Symptomatic knees after ACL-R showed significantly more BTU than asymptomatic ones (p < 0.01).Based on the measured BTU activity in SPECT/CT in symptomatic operated and asymptomatic non-operated knees, intensity thresholds of pathological BTU were established. A BTU threshold of greater than the Median + 1 SD of the asymptomatic non-operated knee was defined as pathological. In both groups the highest mean BTU was found on the femoral, tibial and patellar articular surfaces, the lowest BTU in femoral and tibial regions far from the joint.

Conclusions

The established BTU thresholds for SPECT/CT in knees after ACL-R help to differentiate disease-specific from patient-specific BTU. It could be speculated that BTU in asymptomatic knees equates to the preoperative condition of the knee joint before ACL-R. Therefore, the results of this study help to understand in-vivo loading of the knee and ultimately lead to prediction of development of osteoarthritis in an early stage.

18 F-DOPA uptake does not correlate with IDH mutation status and 1p/19q co-deletion in glioma

Abstract

Objective

The role of amino acid positron emission tomography (PET) in glioma grading and outcome prognostication has not yet been well established. This is particularly true in the context of the new WHO 2016 classification, which introduced a definition of glioma subtypes primarily based on molecular fingerprints. The aim of the present study was to correlate 3,4‑dihydroxy‑6‑[¹⁸F]‑fluoro-l‑phenylalanine (F-DOPA) uptake parameters with IDHmutation, 1p/19q status, and survival outcomes in patients with glioma.

Methods

The study population consisted of 33 patients (17 M/16 F, mean age: 46 ± 13 years) who underwent F-DOPA PET/CT for the evaluation of tumor extent before the start of chemo or radiotherapy. The presence of IDHmutation and 1p/19q status was assessed in all the cases. Tumor volume and semiquantitative uptake parameters, namely SUV_max, tumor-to-normal brain ratio and tumor-to-normal striatum ratio, were calculated for each tumor. Imaging-derived parameters were compared between patients stratified according to molecular fingerprints, using parametric or non-parametric tests, where appropriate. The Kaplan–Meier method was used to assess differences of overall survival (OS) and progression-free survival (PFS) between groups. PET parameters were also tested as prognostic factors in univariate Cox survival regression models.

Results

There were 12 IDH-wild-type and 21 IDH-mutant patients. Stratification according to 1p/19q co-deletion resulted in 20 non-co-deleted and 13 co-deleted patients. Median follow-up time from PET/CT exam was 30.5 months (range 3.5–74 months). Semiquantitative uptake parameters did correlate neither with IDH mutation nor with 1p/19q status. Uptake was similar in low-grade and high-grade tumors, respectively. In addition, F-DOPA uptake parameters, macroscopic tumor volume, or tumor grade did not stratify OS, while a correlation between SUV_max and PFS was shown in the subgroup of astrocytomas. On the other hand, IDH mutation status and presence of 1p/19q co-deletion had a significant impact on survival outcomes. The prognostic value of IDH mutation status was also confirmed in the subgroup of patients with astrocytic tumors.

Conclusions

F-DOPA uptake parameters do not correlate with tumor molecular and histological characteristics. The predictive value of PET-derived parameters on outcomes of survival is limited.

Fundamental study of radiogallium-labeled aspartic acid peptides introducing octreotate derivatives

Abstract

Objective

Somatostatin receptors are highly expressed in neuroendocrine tumors, and many radiolabeled somatostatin analogs for diagnosis and treatment have been developed. To simultaneously detect not only primary cancer but also bone metastases, this study aimed to develop a positron emission tomography probe using generator-produced nuclide Gallium-68 (T_1/2 = 68 min), in which a carrier for primary cancer, a carrier for bone metastases lesions, and a stable gallium complex are introduced into the one molecule. Based on this strategy, the somatostatin receptor-targeted peptide, [Tyr³]-octreotate (TATE), aspartic acid peptide (D_n) with high binding affinity for hydroxyapatite, and Ga-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) as a stable gallium complex were selected. The novel complexes, Ga-DOTA-D_n-TATE (n = 0, 2, 5, 8, or 11), were designed, synthesized, and evaluated. The radiogallium complexes were prepared using the easy-to-handle radioisotope ⁶⁷Ga due to relatively long half-life.

Methods

The radiogallium complex precursor DOTA-D_n-TATE was synthesized by the Fmoc-based solid-phase method and by the air oxidation method to form the disulfide bond. [⁶⁷Ga]Ga-DOTA-D_n-TATE was synthesized by reacting DOTA-D_n-TATE and ⁶⁷Ga. Hydroxyapatite binding assays, in vitro cellular uptake experiments in AR42J tumor cells, in biodistribution experiments in AR42J tumor-bearing mice, were performed using [⁶⁷Ga]Ga-DOTA-D_n-TATE.

Results

The radiochemical purities of [⁶⁷Ga]Ga-DOTA-D_n-TATE were > 96.0%. In in vitro and in vivo experiments, [⁶⁷Ga]Ga-DOTA-D₁₁-TATE had a high affinity for hydroxyapatite and highly accumulated in bone. However, the uptake of [⁶⁷Ga]Ga-DOTA-D₁₁-TATE into somatostatin receptor-positive AR42J cells was lower than that of [⁶⁷Ga]Ga-DOTA-TATE, and the accumulation of [⁶⁷Ga]Ga-DOTA-D₁₁-TATE in tumor was significantly low.

Conclusion

Ga-DOTA-D₁₁-TATE may not be recognized by somatostatin receptor by the introduction of D₁₁, and the charge adjustment may be important for somatostatin receptor-positive cell uptake.

Brain 18 F-FDG distribution: which region is most affected by increased plasma glucose levels?

Clinical feasibility of early scanning after administration of 68 Ga-DOTATOC

Abstract

Objective

Positron emission tomography (PET)/computed tomography (CT) using ⁶⁸Ga-labeled 1,4,7,10-tetraazacyclododecane-N,N′,N″,N‴-tetraacetic acid-d-Phe¹-Tyr³-octreotide (DOTATOC) is usually performed about 1-h post-injection; however, because of rapid blood clearance, the waiting time for scanning could possibly be shortened without affecting diagnostic performance. The purpose of this study was to investigate the feasibility of early scanning at 30 min post-injection.

Methods

Thirty-eight patients who underwent DOTATOC-PET/CT were analyzed. After administration of ⁶⁸Ga-DOTATOC, data acquisition was performed twice, at 30-min and 60-min post-injection. The number of known or suspected pathological lesions, and quantitative values of those lesions and physiological uptake were compared. SUV_max, SUV_peak, metabolic tumor volume (MTV), and total lesion uptake (TLU) were calculated as quantitative values of the pathological lesions.

Results

A total of 125 known or suspected pathological lesions were found at both timepoints, with no differences between the two datasets. The SUV_max, SUV_peak, MTV, and TLU were highly reproducible, with Spearman's ρ of 0.983, 0.986, 0.918, and 0.981, respectively. The average percent differences (%DIFF_ave) defined as the differences of the values divided by the value at 1-h post-injection were 11.1% for SUV_max, 8.5% for SUV_peak, 15.1% for MTV, and 20.6% for TLU. Physiological uptake in the two datasets was closely comparable in the pituitary gland (Spearman's ρ = 0.954, %DIFF_ave = 11.0%), liver (0.989, 3.9%), spleen (0.970, 6.3%), adrenal glands (0.879, 13.0%), and pancreatic uncus (0.946, 12.7%).

Conclusion

The diagnostic performance of visual interpretation should be comparable between DOTATOC-PET/CT images obtained at 30-min and 60-min post-injection. Some differences between quantitative values may exist; however, they appear to be minimal.

Techniques for generating attenuation map using cardiac SPECT emission data only: a systematic review

Abstract

To reliably interpret and perform quantitative analysis, attenuation correction for cardiac single-photon emission computed tomography (SPECT) is fundamental. Thus, knowledge of the patient-specific attenuation map for accurate correction is required in SPECT quantitative imaging. The aim of this systematic review is to present general principles of attenuation correction and provide a structured summary of the approaches that have been proposed for generating the attenuation map for cardiac SPECT. We identified relevant articles published in English pertaining to the attenuation map (AM) determination using SPECT emission data only by searching PubMed, EMBASE, Scopus, and Web of Science databases. Moreover, other articles were hand searched. The protocol of this systematic review was registered in PROSPERO and the code given is CRD42017060512. Transmissionless techniques of determining attenuation map including calculated methods, statistical modeling for simultaneous estimation of attenuation and emission, consistency conditions criteria, using scattered data and other methods were reviewed. Methods for performing attenuation map for cardiac SPECT are developing and the progresses made are promising. However, much work is needed to assess the efficacy of the correction schemes in the clinical routine.

The significant value of predicting prognosis in patients with colorectal cancer using 18 F-FDG PET metabolic parameters of primary tumors and hematological parameters

Abstract

Objects

The purpose was to evaluate the correlation of the pre-treatment hematological parameters with metabolic parameters of primary tumor in baseline ¹⁸F-FDG PET/CT in patients with colorectal cancer (CRC) and estimate the prognostic value of both.

Methods

We retrospectively investigated 231 patients with CRC who underwent baseline ¹⁸F-FDG PET/CT. Routine blood sampling was tested in the same term. PET parameters in term of hematological parameters and pathological characteristics of primary tumor were compared. Kaplan–Meier survival analysis was performed in the patients without distant metastasis. The differences of disease-free survival between groups were compared by log-rank tests.

Results

Neutrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR) were significantly correlated with all the metabolic parameters including maximum standardized uptake value (SUV_max), metabolic tumor volume (MTV) and tumor lesion glycolysis (TLG). The patients with NLR > 3 had higher MTV (24.82 ± 18.16 vs 19.06 ± 13.30, P = 0.039) and TLG (219.04 ± 186.94 vs 166.45 ± 146.39, P = 0.047) than those whose NLR ≤ 3. NLR in those patients with distant metastasis was significantly higher than those without distant metastasis (P = 0.018) while LMR in those patients with distant metastasis was significantly lower than those without distant metastasis (P = 0.032). Survival analysis showed that those patients with low MTV (P = 0.015), low NLR (P = 0.008) and high LMR (P = 0.027) revealed significant survival benefit.

Conclusions

There was a significant association between the pre-treatment hematological parameters and metabolic parameters of baseline ¹⁸F-FDG PET/CT in the patients with CRC. It might be helpful in those patients with high NLR and low LMR to undergo ¹⁸F-FDG PET/CT to detect distant metastasis and predict prognosis.

Comparison of 18 F-Choline PET/CT and MRI functional parameters in prostate cancer

Abstract

Aim

¹⁸F-Choline (FCH) uptake parameters are strong indicators of aggressive disease in prostate cancer. Functional parameters derived by magnetic resonance imaging (MRI) are also correlated to aggressive disease. The aim of this work was to evaluate the relationship between metabolic parameters derived by FCH PET/CT and functional parameters derived by MRI.

Materials and methods

Fourteen patients with proven prostate cancer who underwent FCH PET/CT and multiparametric MRI were enrolled. FCH PET/CT consisted in a dual phase: early pelvic list-mode acquisition and late whole-body acquisition. FCH PET/CT and multiparametric MRI examinations were registered and tumoral volume-of-interest were drawn on the largest lesion visualized on the apparent diffusion coefficient (ADC) map and projected onto the different multiparametric MR images and FCH PET/CT images. Concerning the FCH uptake, kinetic parameters were extracted with the best model selected using the Akaike information criterion between the one- and two-tissue compartment models with an imaging-derived plasma input function. Other FCH uptake parameters (early SUVmean and late SUVmean) were extracted. Concerning functional parameters derived by MRI scan, cell density (ADC from diffusion weighting imaging) and vessel permeability (K_trans and V_e using the Tofts pharmakinetic model from dynamic contrast-enhanced imaging) parameters were extracted. Spearman's correlation coefficients were calculated to compare parameters.

Results

The one-tissue compartment model for kinetic analysis of PET images was selected. Concerning correlation analysis between PET parameters, K₁ was highly correlated with early SUVmean (r = 0.83, p < 0.001) and moderately correlated with late SUVmean (r = 0.66, p = 0.010) and early SUVmean was highly correlated with late SUVmean (r = 0.90, p < 0.001). No significant correlation was found between functional MRI parameters. Concerning correlation analysis between PET and functional MRI parameters, K₁ (from FCH PET/CT imaging) was moderately correlated with K_trans (from perfusion MR imaging) (r = 0.55, p = 0.041).

Conclusions

No significant correlation was found between FCH PET/CT and multiparametric MRI metrics except FCH influx which is moderately linked to the vessel permeability in prostate cancer.

Count-based method for specific binding ratio calculation in [I-123]FP-CIT SPECT analysis

Abstract

Objective

To calculate the specific binding ratio (SBR) appropriately in dopamine transporter (DAT) imaging, a method for extracting the striatal volume of interest (VOI) was developed.

Methods

This study included 200 patients (72 ± 10 years) who were suspected of parkinsonian syndromes (PS) or dementia with Lewy body (DLB). The patients were divided into three groups of PS with dopaminergic degeneration, DLB and non-PS after [¹²³I]ioflupane (FP-CIT) SPECT and clinical follow-up. The image data were reconstructed with CT attenuation correction and scatter correction, and with only CT attenuation correction (CTAC). The new method extracted striatal VOI according to the high-level counts and the average striatum volume, and calculated SBR using the reference occipital counts. The SBR values for each patient were obtained using the Tossici-Bolt method (SBR_Bolt) and our method. Reproducibility of SBR calculation using our method was compared by two operators.

Results

The mean SBR values for the PS and DLB groups were significantly different from that of the non-PS group with both methods. The coefficients of variation of the SBR were significantly smaller with the proposed method compared with those of SBR_Bolt (p < 0.001), except for the CTAC images. There were no differences in SBR between the two operators using our method. The diagnostic accuracies with our method for the PS and DLB groups were 98.4 and 96.0%, respectively.

Conclusion

Our new method for SBR calculation in the FP-CIT SPECT showed less coefficients of variation with high reproducibility, which would be useful for clinical diagnosis and in assessing the severity of diseases in follow-up studies.

The role of 13 N -ammonia in the differential diagnosis of gliomas and brain inflammatory lesions

Abstract

Objective

To investigate the utility of ¹³N-ammonia PET/CT imaging in the differential diagnosis of gliomas and brain inflammations.

Methods

¹³N-ammonia PET/CT imaging data of 77 patients with gliomas and 34 patients with brain inflammations were retrospectively analyzed. No patients received any treatment before ¹³N-ammonia imaging. All the patients were diagnosed by stereotactic biopsy or clinical follow-up. Visual and semi-quantitative analysis was performed to analyze the results of ¹³N-ammonia imaging. Finally, the uptake ratios of each lesion were calculated and its differences among different groups were tested with one-way ANOVA.

Results

29.4% inflammations, 51.6% low-grade gliomas and 91.3% high-grade gliomas were positive by visual analysis in ¹³N-ammonia imaging. The sensitivity, specificity and accuracy for the diagnosis of gliomas were 75.3%, 55.8% and 67.8%, respectively. As for semi-quantitative analysis, the T/G ratios of inflammatory lesions, low-grade gliomas and high-grade gliomas were 0.88 ± 0.24, 1.04 ± 0.43 and 1.43 ± 0.49, respectively. One-way ANOVA revealed that the T/G ratios of high-grade gliomas were significantly higher than those of low-grade gliomas and inflammations (P < 0.05), but there was no statistical difference between low-grade gliomas and inflammations (P = 0.118). Among the inflammatory lesions, T/G ratios were not statistically different between infectious and demyelinating lesions (P > 0.05). ROC curve analysis showed that the optimal cut-off value of T/Gratio in distinguishing gliomas from inflammations was 1.21 with the AUC 0.78. The sensitivity, specificity, accuracy, PPV and NPV were 52.9%, 94.4%, 65.3%, 95.7% and 45.9%, respectively. ROC curve analysis showed that the optimal cut-off value of T/G ratio in distinguishing high-grade gliomas from low-grade gliomas was 1.06 with the AUC 0.78. The sensitivity, specificity, accuracy, PPV and NPV were 81.5%, 67.7%, 76.5%, 81.5% and 67.7%, respectively. ROC curve analysis showed that the optimal cut-off value of T/G ratio in distinguishing high-grade gliomas from low-grade gliomas and inflammations was 1.19 with the AUC 0.84. The sensitivity, specificity, accuracy, PPV and NPV were 70.4%, 85.1%, 78.5%, 79.2% and 78.1%, respectively.

Conclusions

¹³N-ammonia imaging is effective in distinguishing high-grade gliomas from low-grade gliomas and inflammations, but its role in the differential diagnosis of low-grade gliomas and brain inflammatory lesions is limited, and the accuracy needs to be improved.

Dental Research

Load-deflection characteristics of coated and noncoated nickel-titanium wires in self-ligating brackets using a modified bending test: An in vitro study
Tripti Tikku, Rohit Khanna, Akhil Agarwal, Kamna Srivastava, Shashank Shekhar, Ivy Shukla

Dental Research Journal 2019 16(1):1-6

Background: To determine and compare the force-deflection values of different types of nickel-titanium (NiTi) wires during unloading phase at varying deflections, that is 1 mm, 1.5 mm, 2 mm, and 2.5 mm, with the use of self-ligating ceramic brackets using modified bending test on a typodont under controlled temperature conditions. Materials and Methods: In this in vitro study total of 45 wires of ovoid shape of three different NiTi wires – pseudoelastic NiTi (Group I), heat activated NiTi (Group II), and esthetic coated NiTi (Group III) for maxillary arch were tested after insertion in ceramic self-ligating brackets bonded to plastic teeth of phantom jaw . The maxillary left lateral incisor was removed to simulate a malpositioned tooth which acted as the load site, and load-deflection characteristics were measured during unloading using Instron, and data analyzed statically by two-way analysis of variance ,Tukey's post hoc test, intraclass correlation coefficient and Pearson correlation coefficient. A two-sided (α = 2) P < 0.05 was considered statistically significant. Results: When wires were compared at each deflection statistically significant difference was observed between the three groups of wires (Group I > Group II > Group III) at all the four levels of deflection except for Group II versus Group III at 1 mm, 1.5 mm, and 2 mm of deflection. Statistically significant difference was noted in mean load values for comparisons made at different deflections for each wire except for the comparison made at 1.5 versus 2 mm for Group II and Group III. Conclusion: Overall comparison showed esthetic coated Ni-Ti wires gave significantly lower mean load values, followed by heat activated and pseudoelastic NiTi wires. Thus, heat activated NiTi wires are best suited in patients with severe malpositions/periodontitis, while for esthetically conscious patients esthetic coated NiTi can be used.

Effects of menthol-flavored substances at the cellular level on oral mucosal sites
Nanda Prasad, Sarvesh Vijay, A Yashwanth Reddy, S Nonitha

Dental Research Journal 2019 16(1):7-11

Background: The purpose of this study was to determine the effects of menthol-flavored substances at the cellular level in different mucosal sites of the oral cavity and to compare the cellular changes between individuals without the habit of chewing menthol-flavored substances and individuals with the habit. Materials and Methods: This was an experimental cytology study including a total of 500 individuals belonging to the age group of 18–45 years based on the inclusion or exclusion criteria. The selected participants were divided into two groups of 250 participants each, based on participants not having the habit of chewing menthol-flavored substances (Group I) and participants having the habit of chewing menthol-flavored substances (Group II). Cytological smears were taken by gently scraping the mucosal surfaces in different sites of the oral mucosa using a wooden spatula and stained with Papanicolaou, analyzed under microscope for any cellular changes. The results were tabulated and statistically analyzed using Chi-square test and Fisher's exact test. P < 0.05 was considered statistically significant. Results: Micronuclei seen in all the participants belonging to group with the habit of chewing menthol-flavored substances with a P < 0.001 which was considered highly significant. Alteration in the nuclear-cytoplasmic ratio was also seen P = 0.001, which showed significant at 1% significance level. Conclusion: Participants with habit of chewing menthol-flavored substances showed the presence of micronuclei and slight alteration in the nuclear-cytoplasmic ratio, which could be directly related to genotoxicity and cell damage.

Impact of occupational dental erosion on oral health-related quality of life among battery factory workers in Bengaluru, India
Amit Kumar, Manjunath P Puranik, KR Sowmya, Soni Rajput

Dental Research Journal 2019 16(1):12-17

Background: A greater understanding of impact of occupational dental erosion on oral health-related quality of life (OHRQoL) will sensitize both employee and employers to adopt strict protective measures for oral health. The research aimed to determine the relationship between occupational dental erosion and OHRQoL among battery and other factory workers in Bengaluru, India. Materials and Methods: This cross-sectional comparative study enrolled a total of 400 workers. Structured proforma assessed information on sociodemographic details, oral hygiene practices, adverse oral habits, and work-related practices. OHRQoL was determined using oral health impact profile-14 (OHIP-14). Dental erosion was measured using Smith and Knight's tooth wear index modified by Millward et al. 1994 scoring system independent t-test, Mann–Whitney U-test and Spearman's correlation was performed. P < 0.05 was considered statistically significant. Results: The mean age of the participants in the study and control groups was 43.11 ± 8.02 and 45.93 ± 6.16 years, respectively. Less than half of the participants in the study group had positive behavioral work practice. The prevalence and severity of dental erosion was significantly higher in study group (39.5%) than control group (11.5%). Mean OHIP-14 score was significantly lower in study group (23.88 ± 0.88) than control group (26.06 ± 9.67). Dental erosion significantly correlated with work experience and OHIP-14. Conclusion: The findings highlight the impact of occupational dental erosion on OHRQoL. Measures to enhance occupational safety thereby reducing exposure to occupational hazards are needed.

Comparative investigation of primary stability of four different dental implants in low-density bone model
Saied Nokar, Amirali Reza Rasouli-Ghahroudi, Elham Shidvash, Faezeh Atri

Dental Research Journal 2019 16(1):18-23

Background: Primary stability is one of the prerequisites of immediate loading. The aim of this study was to compare the primary stability of four different implant systems in low-density bone models. Materials and Methods: In this in vitro experimental study, 20 fixtures from four implant body designs were selected: Zimmer Tapered Screw-Vent (ZTSV), NobleReplace Tapered (NRT), Replace Select Tapered (RST), and Dentium SuperLine (DSL). Fixtures were inserted in low-density bone models according to manufacturer drilling protocol by one surgeon. Measurement of insertion torque value (ITV), resonance frequency analysis (implant stability quotient [ISQ]), and reverse torque value (RTV) was recorded for each fixture. The data were analyzed with one-way ANOVA and post hoc tests (Tukey honestly significant difference) (P < 0.05). Results: ZTSV had significantly lower amount of insertion torque in comparison to other systems (P = 0.045). RTV was significantly lower in ZTSV in comparison to DSL and NRT (P = 0.004). ISQ value in NRT (ISQ = 67) was significantly higher than other systems (P = 0.000). The lowest amount of ISQ was in RST system (ISQ = 53) with significant difference (P = 0.000). Conclusion: This study demonstrated that primary stability of different implant systems was not comparable and implant design was effective on ITV, RTV, and ISQ.

Assessment of antimicrobial activity of different concentrations of Tinospora cordifolia against Streptococcus mutans: An in vitro study
Sankalp Agarwal, Priyadarshini H Ramamurthy, Bennete Fernandes, Avita Rath, Preena Sidhu

Dental Research Journal 2019 16(1):24-28

Background: The antimicrobial property of Tinospora cordifolia has been tested against a variety of microorganisms in the literature. The present study aimed to assess the antimicrobial activity of different concentrations of commercially available T. cordifolia powder against Streptococcus mutans. Materials and Methods: An in vitro study was undertaken in which extract of T. cordifolia was obtained using 100% ethanol by maceration. Seven different concentrations were prepared and tested against S. mutans in brain–heart infusion agar medium. Plates were incubated aerobically at 37°C for 48 h, and zone of inhibition was measured using Vernier caliper. 0.2% chlorhexidine and dimethylformamide were used as positive and negative controls respectively. The data were analysed by descriptive analytic tests. Results: The maximum antibacterial activity of T. cordifolia was observed with a volume of 40 μl at 2% concentration with a zone of inhibition of 19 mm. A 30 μl volume of 0.2% chlorhexidine showed a zone of inhibition of 28 mm, and no zone of inhibition was observed with dimethylformamide. Conclusion: Tinospora exhibited antimicrobial activity against S. mutans. However, it needs to be confirmed further with in vivo studies.

Association between quality of sleep and chronic periodontitis: A case–control study in Malaysian population
Vijendra Pal Singh, Joe Yin Gan, Wei Ling Liew, Htoo Htoo Kyaw Soe, Sowmya Nettem, Sunil Kumar Nettemu

Dental Research Journal 2019 16(1):29-35

Background: Periodontitis is a public health concern since it is a major factor in tooth loss worldwide and has association with many systemic diseases. Sleep is a complex and essentially biological process and a critical factor for maintaining mental and physical health. Since inflammation is characteristic of both chronic periodontitis and sleep deprivation, few studies in recent years present the contradictory results regarding this potential association. The objective of the present study was to investigate the association between quality of sleep and chronic periodontitis. Materials and Methods: A total of 200 individuals participated in this study. All participants underwent a comprehensive clinical periodontal examination. Case–control were identified using the Centers for Disease Control and Prevention/American Academy of Periodontology case definitions for periodontal disease. The quality of sleep was assessed by Pittsburgh Sleep Quality Index. The univariate and multivariate logistic regression analysis was used to test the influence of variables (quality of sleep, age, sex, ethnicity, education, and socioeconomic status), in the occurrence of periodontitis. Odds ratio (OR) and respective confidence intervals (CIs) were calculated and reported. P ≤0.05 was considered statistically significant. Results: The prevalence of poor quality of sleep was 56.75% in cases (periodontitis group) and 43.24% in control group. There was positive association between quality of sleep and chronic periodontitis (OR = 3.04; 95% CI = 1.42–6.5; P = 0.004). In multivariate logistic regression analysis, only the age was significantly related to the periodontitis (OR = 1.11; 95% CI = 1.07–1.41; P < 0.001), other variables failed to reach the significant level. Conclusion: Poor quality of sleep was significantly associated with chronic periodontitis. Only the age was significantly related to periodontitis among the other covariable measured.

Sealants revisited: An efficacy battle between the two major types of sealants – A randomized controlled clinical trial
B Prathibha, P Parthasarthi Reddy, Md Shakeel Anjum, M Monica, BH Praveen

Dental Research Journal 2019 16(1):36-41

Background: The aim of this study is comparing the retention and caries preventive effect of the glass-ionomer fissure sealant and resin-based fissure sealant. Materials and Methods: A randomized-controlled split-mouth study was conducted to compare the retention and the caries preventive effect of light-cured resin-based sealant (3M ESPE) and glass ionomer sealant (Fuji VII). The sealants were applied to either the right or the left lower mandibular molars (7-9 yrs of age) in 120 school children, based on the randomization process. They were recalled for assessment of clinical retention at intervals of 3, 6, and 12 months. The caries-preventive effect between the two materials was tested statistically by the McNemar's test for matched pairs, and the differences observed with regard to the retention of the materials was tested by Chi-square tests. The level of significance was set to be at P < 0.05. Results: At the end of 12th month, sealant retention is found to be higher in the resin-based sealant group compared to the glass ionomer group. In the glass ionomer sealants placed, 101 (91%) were caries-free and 10 (9%) had caries. In the resin-based sealant, 105 (94.60%) had sound teeth and 6 (5.4%) had dental caries (P = 0.34). Conclusion: The glass ionomer sealant was less retentive when compared to resin sealants. The caries incidence between the glass ionomer and resin-based sealants was not statistically significant.

A comparative study of the clinical efficiency of chemomechanical caries removal using Carie-Care gel for permanent teeth of children of age group of 12–15 years with that of conventional drilling method: A randomized controlled trial
Priyanka Sontakke, Prateek Jain, Aniket Dhote Patil, Gautam Biswas, Pramod Yadav, Diljot Kaur Makkar, Vikas Jeph, Banu Pyari Sakina

Dental Research Journal 2019 16(1):42-46

Background: Dental caries is considered as one of the most serious dental diseases that results in localized dissolution and destruction of the calcified tooth tissues. As possible alternatives to conventional techniques of caries removal, chemomechanical caries removal systems have emerged. This study aims to clinically observe the advantages of chemomechanical method of caries removal over conventional technique. Materials and Methods: Inthis randomized controlled trial a total of 60 children with Class 1 open carious lesions were selected for the study. They were divided into two equal groups according to a method of caries removal (30 chemomechanical and 30 conventional on permanent molars). In Group A, caries was removed using the Carie-Care system and in Group B with the conventional drill and were restored equally with glass ionomer cement. The visual analogy face scale was used to determine the level of anxiety in children at baseline, during treatment and after treatment. Results: The results were subjected to statistical analysis using Student's unpaired t-test. It showed that though chemomechanical technique took a marginal increase in time compared to the conventional technique, it was found to be more comfortable for all the children. Conclusion: Chemomechanical technique though time-consuming is definitely superior compared to the conventional technique provided we use a less technique sensitive restorative material which retains in the oral cavity for longer period. It is definitely a better treatment protocol in school-based dental treatment and atraumatic restorative dentistry compared to the conventional technique.

The effect of office bleaching on the color and bond strength of resin restorations
Homayoon Alaghehmand, Marzieh Rohaninasab, Ali Bijani

Dental Research Journal 2019 16(1):47-52

Background: Bleaching may affect the bond strength of existing composite fillings and may weaken it. Hence, the aim of this study was to find the best method of in-office bleaching with the least effect on microshear bond strength (MSBS) of existing composite resin fillings to tooth structure. Materials and Methods: In this in vitro study, Class V cavities were prepared on buccal surface of 50 extracted third human sound molars. The cavities in 25 teeth had enamel axial walls, Group E, which were divided into five subgroups of E1 through E5 and in 25 teeth had dentin axial walls, Group D, which were divided into five subgroups of D1 through D5. Cavities were treated with Single Bond 2 adhesive system and restored with composite resin (Z250). The corresponding subgroups received similar bleaching methods and materials; 1 – not bleached, 2 – hydrogen peroxide (HP) 25%, 3 – HP + ultraviolet light, 4 – HP + light-emitting diode-curing device, and 5 – HP + diode laser. Teeth colors were monitored before and after bleaching, and MSBS test and failure modes were examined. Results were analyzed with one-way ANOVA and Kruskal–Wallis tests. P < 0.05 was considered significant. Results: One-way ANOVA did not show differences in MSBS of enamel subgroups but showed significant differences in dentin subgroups (P < 0.00). Adhesive fracture in all of the subgroups was the most frequent mode of failure. Kruskal–Wallis test showed that laser was the most effective instrument to change ΔE. Conclusion: Diode laser was the best method for tooth bleaching because lowering the shear bond strength between composite resin and enamel was minimum and also had the most ΔE in tooth bleaching.

In vitro evaluation of coronal discoloration following the application of calcium-enriched mixture cement, Biodentine, and mineral trioxide aggregate in endodontically treated teeth
Solmaz Araghi, Atefeh Khavid, Mostafa Godiny, Mahshid Saeidipour

Dental Research Journal 2019 16(1):53-59

Background: This study sought to assess and compare coronal discoloration following the application of white mineral trioxide aggregate, Biodentine, and calcium-enriched mixture cement in endodontically treated teeth. Materials and Methods: In this in vitro experimental study, 64 freshly extracted sound human premolars were selected, cleaned, and stored in saline. After cleaning, shaping, and obturation the root canal of the teeth, the teeth were randomly assigned to one control (n = 4) and three experimental (n = 20) groups. In the experimental groups, the cement were applied over the canal orifices in 3-mm thickness. All teeth were then restored with composite resin. Color parameters, according to the CIE L*a*b* system, were measured using Vita Easyshade spectrophotometer before application of cement and at 1 week, 1 month, 2 months, and 3 months after the application of cement. The recorded values were statistically analyzed using descriptive and analytical statistics. For analytical statistics, Kolmogorov–Smirnov test was applied to assess normal distribution of data. ANOVA was used to compare the results at baseline and repeated measures. P < 0.05 was considered statistically significant Results: Significant differences were noted in color change (ΔE) between all time points except between ΔE4 (2 months) and ΔE5 (3 months) (P < 0.01). However, tooth discoloration caused by the three cement was not significantly different (P = 0.343). Conclusion: The three tested cement were not significantly different in terms of causing coronal discoloration in endodontically treated teeth.

Isolation of a Stable Pyridine Radical Anion

Chem. Commun., 2019, Accepted Manuscript
DOI: 10.1039/C8CC09700C, Communication

Jan Schröder, Daniel Himmel, Daniel Kratzert, Valentin Radtke, Sabine Richert, Stefan Weber, Tobias Böttcher
Reduction of 2,6-bis(diazaboryl)pyridine with KC8 gives a room-temperature-stable yellow colored solution containing the corresponding radical anion. The radical was characterized by single crystal XRD, EPR spectroscopy, UV-vis absorption spectroscopy and...
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Green Weenie Award: Nuclear War Will Save Us!

Green-Weenie-Mug-copy.jpg?is-pending-loa

Powerlineline's Green Weenie of the Week Award has now raised the bar against which all green weenies will now be measured. ~ctm From Powerline. Posted on January 4, 2019 by Steven Hayward in Climate, Green Weenie Award As I suggested in my latest Loose Ends post earlier today, our standards for giving out one of…

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Halide-assisted activation of atomic hydrogen for photoreduction on two-liquid interfacial plasmonic arrays

Chem. Commun., 2019, Accepted Manuscript
DOI: 10.1039/C8CC09619H, Communication

Yue Xu, Fanfan Yu, Mengke Su, Shanshan Du, Honglin Liu
Here we show two-liquid interfacial 3D plasmonic arrays for SERS examination on direct photoreduction of p-nitrothiophenol (4-NTP) to p-aminothiophenol (4-ATP) without the need for traditional catalysts and reductants, revealing the...
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Zirconium bistriazolylpyridine phosphonate materials for efficient, selective An(III)/Ln(III) separations

Chem. Commun., 2019, Accepted Manuscript
DOI: 10.1039/C8CC07892K, Communication

Jessica Veliscek-Carolan, Aditya Rawal
Direct synthesis of ZrCl4 and bistriazolylpyridine phosphonate has produced novel sorbent materials that, for the first time, demonstrate selective extraction of Am(III) in the presence of excess Eu(III). Further, the...
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Aggregation-induced emission (AIE)-active molecules bearing singlet oxygen generation activities: the tunable singlet-triplet energy gap matters

Chem. Commun., 2019, Accepted Manuscript
DOI: 10.1039/C8CC09230C, Communication

Chengkai Zhang, Yanqian Zhao, Dandan Li, Jiejie Liu, Heguo Han, Daoyu He, Xiaohe Tian, Shengli Li, Jieying Wu, Yupeng Tian
Herein, a series of photosensitizers were constructed of α, β and γ-isomers of terpyridine and the corresponding N-methylation derivatives. Benefiting from the tunable singlet-triplet energy gap and aggregation-induced emission characteristics,...
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Study reconstructing ocean warming finds ocean circulation changes may account for significant portion of sea level rise

Study suggests that in the last 60 years up to half the observed warming and associated sea level rise in low- and mid- latitudes of the Atlantic Ocean is due to changes in ocean circulation. Over the past century, increased greenhouse gas emissions have given rise to an excess of energy in the Earth system.…

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[ASAP] Long-Range Activationless Photostimulated Charge Transport in Symmetric Molecular Junctions

TOC Graphic

ACS Nano

DOI: 10.1021/acsnano.8b08662

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Investigation on leaching behaviour of toxic metals from biomedical ash and its controlling mechanism

Abstract

It is comprehensible that disposal of biomedical ash (BMA) is a serious threat to human life and to the environment compared to any other type of waste without proper treatment. In the present study, it is focused in studying the leaching behaviour and its controlling mechanism to predict the contamination levels of BMA. Experimental investigation was carried out to determine the physico-chemical properties of BMA. The morphological and mineralogical composition was performed by SEM equipped with EDAX and XRD. A leaching pattern was identified for various heavy metals simultaneously (Hg, Se, As, Fe, Cd, Zn, Pb, Ca, Co, Ni, Cr and Cu) by varying pH (3, 5, 7, 9, and 11) via a pH-dependent batch leaching test using AAS and ICP. Major oxidation states of leached mineral/metal were established by Visual MINTEQA 3.1. Leaching test results show that a high concentration of Hg (9.3 mg/l), Se (2.4 mg/l) and As (9.7 mg/l) at pH 11 was obtained. Characterisation studies substantiate 60% of calcium silicate presence and major minerals like ettringite, calcite and thermonatrite. Geochemical modelling reveals that leached elements were solubility controlled except As and Se. It is inferred that, presence/formation of ettringite, calcite and thermonatrite minerals are responsible for immobilizing/reduced leaching of toxic heavy metals in alkaline environment except for Hg, Se and As as they are highly mobile in an alkaline condition which can be reduced by adopting a suitable pretreatment option so as to reduce the contamination levels of handling even untreated waste disposal.

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Duration analysis on the adoption behavior of green control techniques

Abstract

Based on field survey data of 366 traditional households (THs) and 364 family farms (FFs) from Huang-Huai-Hai Plain, a discrete-time cloglog model for parameter estimation was constructed to reveal factors that affect the two types of farms' duration from the awareness to the adoption of green control techniques (GCTs). Differences in the influencing factors affecting the duration of the two types of farmers were also discussed. The research results are as follows. First, the duration from awareness to adoption of GCTs is significantly shorter in FFs than that in THs. Second, a higher degree of education, risk preference, family financial status, perceived ease of use and usefulness of the technique, and extension of media and supervision of agricultural technique extension departments of local governments significantly reduce the duration from awareness to adoption of GCTs by THs and FFs, whereas a male head of household prolongs the duration. Third, the age, farm size, and number of laborers exert different impacts on the duration from awareness to adoption of GCTs by THs and FFs.

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Butyrylcholinesterase—a potential plasma biomarker in manganese-induced neurobehavioral changes

Abstract

Groundwater particularly drinking water contamination with metals has created an environmental disaster in Bangladesh. Manganese (Mn), an essential trace element, plays a key role in the development and function of the brain. Excess Mn exposure is reported to be associated with complex neurological disorders. Here, we have found a notably large extent of Mn above the permissive limit in the tube-well water of Rajshahi and Naogaon districts in Bangladesh. Higher levels of Mn in hair and nail samples, and a decreasing level of butyrylcholinesterase (BChE) activity were detected in plasma samples of the human subjects recruited from Naogaon district. Mn concentrations in water, hair, and nails were negatively correlated with the plasma BChE levels in Mn-exposed populations. To compare and validate these human studies, an animal model was used to determine the in vivo effects of Mn on neurobehavioral changes and blood BChE levels. In elevated plus maze, the time spent was significantly reduced in open arms and increased in closed arms of Mn-exposed mice compared to control group. The mean latency time to find the platform was declined significantly in control mice compared to Mn-treated group during 7 days in Morris water maze test, and Mn-exposed group also spent significantly less time in the desired quadrant as compared to the control group in probe trial. BChE activity was significantly reduced in Mn-exposed mice compared to control mice. Taken together, these results suggest that plasma BChE levels may serve as reliable biomarker of Mn-induced neurotoxicity related to behavioral changes.

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River Basin Management Plans as a tool for sustainable transboundary river basins’ management

Abstract

Data availability and the existence of exchange mechanisms are considered crucial issues for the management of water bodies shared among riparian countries. Moreover, common legislative and technical frameworks are assets that foster the management of transboundary waters in an integrated and sustainable manner. The River Basin Management Plans of the European Union's Water Framework Directive implementation process not only incorporate a cooperative framework, but also include open access internet-based databases that can enhance cooperation and shed light on water-related conflicts among countries that share transboundary waters. The proposed methodological approach in this research is applied in four transboundary river basins, where Greece is the downstream country, and the upstream countries are not all member states of the European Union. The areas of dispute were found in the 2nd Water Convention Report. For each particular case study, data and information from the respective River Basin Management Plans were used to investigate the actual situation. The results demonstrated that significant conflict situations in the past, which involved both water quality and water quantity issues, could be resolved using continuous and reliable datasets included in the management plans. The use of freely available data sources renders the findings of this work useful for the sustainable management of shared waters.

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A photosynthetic algal microbial fuel cell for treating swine wastewater

Abstract

A photosynthetic algal (Chlorella vulgaris) microbial fuel cell (PAMFC) with double chambers was adopted for power production and removal of carbon and nitrogen in swine sewerage that could provide nutrients for the growth of C. vulgaris. C. vulgaris was expected to utilize carbon dioxide (CO₂) delivered from the anode chamber and generate oxygen as an electron acceptor by photosynthesis. PAMFC presented a maximum voltage output of 0.747 V and a maximum power density of 3720 mW/m³ at 240 h, much higher than that of the standalone MFC. 85.6%, 70.2%, and 93.9% removal of ammonia nitrogen, total nitrogen (TN), and total organic carbon (TOC), respectively, were obtained in the anode chamber of the PAMFC system, while the corresponding removal in MFC was 83.1%, 56.0%, and 87.2%, respectively. PAMFC also presented a much higher removal of ammonia nitrogen (68.7%) in the cathode chamber than MFC (47.5%). The results indicated the superiority of the PAMFC device for carbon and nitrogen removal.

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New study attempts to “squeeze out” uncertainty in climate models

From the "we're gonna need a bigger computer" department. Climate model uncertainties ripe to be squeezed The latest climate models and observations offer unprecedented opportunities to reduce the remaining uncertainties in future climate change, according to a new study. Although the human impact of recent climate change is now clear, future climate change depends on how…

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Exposure of non-target small mammals to anticoagulant rodenticide during chemical rodent control operations

Abstract

The extensive use of anticoagulant rodenticides (ARs) results in widespread unintentional exposure of non-target rodents and secondary poisoning of predators despite regulatory measures to manage and reduce exposure risk. To elucidate on the potential vectoring of ARs into surrounding habitats by non-target small mammals, we determined bromadiolone prevalence and concentrations in rodents and shrews near bait boxes during an experimental application of the poison for 2 weeks. Overall, bromadiolone was detected in 12.6% of all small rodents and insectivores. Less than 20 m from bait boxes, 48.6% of small mammals had detectable levels of bromadiolone. The prevalence of poisoned small mammals decreased with distance to bait boxes, but bromadiolone concentration in the rodenticide positive individuals did not. Poisoned small mammals were trapped up to 89 m from bait boxes. Bromadiolone concentrations in yellow-necked mice (Apodemus flavicollis) were higher than concentrations in bank vole (Myodes glareolus), field vole (Microtus agrestis), harvest mouse (Micromys minutus), and common shrew (Sorex araneus). Our field trials documents that chemical rodent control results in widespread exposure of non-target small mammals and that AR poisoned small mammals disperse away from bating sites to become available to predators and scavengers in large areas of the landscape. The results suggest that the unintentional secondary exposure of predators and scavengers is an unavoidable consequence of chemical rodent control outside buildings and infrastructures.

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Degradation of tetracyclines in manure-amended soil and their uptake by litchi ( Litchi chinensis Sonn.)

Abstract

The environmental and human health risk posed by veterinary antibiotics is of global concern. Antibiotic uptake by herbal plants has been studied, but little is known about perennial woody fruit crops. Litchi (Litchi chinensis Sonn.), a longevial fruit tree, is routinely fertilized with animal manure and, therefore, may be at risk of antibiotic uptake into its fruits. This study investigated the degradation of chlortetracycline and doxycycline present in manure used to amend orchard soil, and their subsequent assimilation by litchi plant, as affected by manure application rate. The results show that half-lives of chlortetracycline and doxycycline in soil were decreased by increased manure rate, with an average of 27 and 59 days, respectively. Chlortetracycline was readily transported to litchi shoots and increased with the growth of litchi plants. Doxycycline predominantly remained in the roots, and underwent growth dilution in the plants. The two tetracyclines could not be detected in fruits from litchi trees when applied with manures, at various rates, over 2 years. For litchi, chlortetracycline may pose human health risk through manure application, but doxycycline is unlikely to do so. Long-term field experiments are required to monitor antibiotic accumulation in fruits of perennial fruit trees fertilized with animal manure.

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Effect of irrigation with detergent-containing water on foxtail millet shoot biomass and ion accumulation

Abstract

Water shortage leads farmers to use sewages for irrigation. Sewages contain a large amount of laundry detergent. In this study the impact of irrigation by contaminated water on shoot biomass and seed germination of foxtail millet (Setaria italica) was investigated. The research was conducted as laboratory and pot experiments. Iso-potentials (− 0.042, − 0.077, and − 0.415 MPa) of polyethylene glycol (PEG, water deficit treatment) and laundry detergent (contamination treatment) made the laboratory experiment treatments. The pot experiment included contamination factor (0, 0.1, 1, and 10 g L⁻¹ of laundry detergent) and deficit irrigation factor (irrigation interval of 1, 2, and 3 days). Results of this study showed that at the iso-potential, laundry detergent had more negative effect on seed germination traits when compared with PEG. There was no germination at − 0.415 MPa of laundry detergent. Both drought and contamination reduced dry forage yield, plant height, leaf number, leaf area, leaf dry and fresh weight, stem dry, and fresh weight. Detergent concentration of 10 g L⁻¹ with irrigation interval of 3 days had a forage yield reduction of 63% compared to control (laundry detergent concentration of 0 g L⁻¹ with irrigation interval of 1 day). Detergent concentration of 10 g L⁻¹ with irrigation interval of 1 day had a sodium increase of 1847% compared to control. Based on the results of this study, it is recommended not to irrigate foxtail millet farm by contaminated water with laundry detergent higher than 1 g L⁻¹.

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