Salivary and urinary assessment of fluoride and silver ion concentrations after silver diamine fluoride application in children: a prospective cohort study

PURPOSE

The purpose of the study was to determine the fluoride (F) and silver (Ag) ions levels in the saliva and urine of healthy children after silver diamine fluoride (SDF) application on dental carious lesions.

METHODS

Sixty children (4-6 years with ≥ 3 caries lesions) were recruited from the outpatient department of Pediatric Dentistry. From each child, 3 ml unstimulated saliva samples were collected at baseline, one hour, and 24 h after SDF application. Similarly, 3 ml urine samples were collected prior to and after 24 h of SDF application. F and Ag ion concentrations were determined by fluoride ion-selective electrode (ISE) and inductively coupled plasma mass spectrometry (ICPMS), respectively.

RESULTS

The mean ± standard deviation (SD) baseline, 1-h, and 24-h salivary F concentrations (ppm) were 0.07 ± 0.07, 0.93 ± 0.48, and 0.19 ± 0.19, respectively, while the mean baseline and 24-h urinary F concentrations (ppm) were 0.33 ± 0.20 ppm and 0.43 ± 0.25 ppm, respectively. The mean baseline, 1-h, and 24-h salivary Ag concentrations (ppb) were 4.22 ± 3.15, 4198 ± 350, and 56.93 ± 37, respectively. The mean baseline and 24-h urinary Ag concentrations (ppb) were 2.80 ± 2.93 ppb and 4.72 ± 4.0 ppb, respectively. There were statistically elevated F and Ag ion concentrations at 1 h and 24 h after SDF application as compared to the baseline.

CONCLUSION

Salivary and urinary F and Ag ions concentrations elevated significantly at 24 h following SDF applications in children. A significant high recovery of these ions in urine indicates minimal systemic absorption, thus intermittent topical application of 38% SDF has a minimal risk of toxicity.

Biomarkers of bleeding and venous thromboembolism in patients with acute leukemia

BACKGROUND

Coagulopathy and associated bleeding and deep vein thrombosis (DVT) are major causes of morbidity and mortality in patients with acute leukemia. The underlying mechanisms of these complications have not been fully elucidated.

OBJECTIVES

To evaluate the associations between biomarker levels and bleeding and DVT in acute leukemia patients.

METHODS

We examined plasma levels of activators, inhibitors, and biomarkers of the coagulation and fibrinolytic pathways in patients aged ≥18 years with newly diagnosed acute leukemia compared with those of normal controls. Multivariable regression models were used to examine the association of biomarkers with bleeding and DVT in acute leukemia patients. The study included 358 patients with acute leukemia (29 with acute promyelocytic leukemia [APL], 253 with non-APL acute myeloid leukemia, and 76 with acute lymphoblastic leukemia) and 30 normal controls.

RESULTS

Patients with acute leukemia had higher levels of extracellular vesicle tissue factor (EVTF) activity, phosphatidylserine-positive extracellular vesicles, plasminogen activator inhibitor-1, plasmin-antiplasmin complexes, and cell-free DNA and lower levels of citrullinated histone H3-DNA complexes compared with normal controls. APL patients had the highest levels of EVTF activity and the lowest levels of tissue plasminogen activator among acute leukemia patients. There were 41 bleeding and 23 DVT events in acute leukemia patients. High EVTF activity was associated with increased risk of bleeding (subdistribution hazard ratio, 2.30; 95% CI, 0.99-5.31), whereas high levels of plasminogen activator inhibitor-1 were associated with increased risk of DVT (subdistribution hazard ratio, 3.00; 95% CI, 0.95-9.47) in these patients.

CONCLUSION

Our study shows alterations in several biomarkers in acute leukemia and identifies biomarkers associated with risk of bleeding and DVT.

Biomarkers of bleeding and venous thromboembolism in patients with acute leukemia

Background

Coagulopathy and associated bleeding and venous thromboembolism (VTE) are major causes of morbidity and mortality in patients with acute leukemia. The underlying mechanisms of these complications have not been fully elucidated.

Objectives

To evaluate the associations between biomarker levels and bleeding and VTE in acute leukemia patients.

Patients/Method

We examined plasma levels of activators, inhibitors and biomarkers of the coagulation and fibrinolytic pathways in patients ≥18 years with newly diagnosed acute leukemia compared to healthy controls. Multivariable regression models were used to examine the association of biomarkers with bleeding and VTE in acute leukemia patients. The study included 358 patients with acute leukemia (29 acute promyelocytic leukemia [APL], 253 non-APL acute myeloid leukemia [AML] and 76 acute lymphoblastic leukemia [ALL]), and 30 healthy controls.

Results

Patients with acute leukemia had higher levels of extracellular vesicle (EV) tissue factor (TF) activity, phosphatidylserine-positive EVs, plasminogen activator inhibitor-1 (PAI-1), plasmin-antiplasmin complexes, cell-free DNA and lower levels of citrullinated histone H3-DNA complexes compared to healthy controls. APL patients had the highest levels of EVTF activity and the lowest levels of tissue plasminogen activator among the acute leukemia patients. There were 41 bleeding and 37 VTE events in acute leukemia patients. High EVTF activity was associated with increased risk of bleeding (sHR 2.30, 95%CI 0.99-5.31) whereas high PAI-1 was associated with increased risk of VTE (sHR 3.79, 95%CI 1.40-10.28) in these patients.

Conclusions

Our study shows alterations in several biomarkers in acute leukemia and identifies biomarkers associated with risk of bleeding and VTE.

Self-Assembled Nanostructures from Amphiphilic Sucrose-Soyates for Solubilizing Hydrophobic Guest Molecules

We studied self-assembly and colloidal properties of poly(ethylene glycol) (pEG) conjugated sucrose soyate polyols (PSSP). These molecular platforms were synthesized by covalently connecting PEGs of different molecular weights (M_n) (12 and 16 ethylene oxide units) to epoxidized sucrose soyate (ESS). The synthesized PSSP products showed amphiphilicity, reduced water surface tension, and exhibited critical Aggregation Concentration (CAC) within the range of 0.3-0.4 mg/mL. We observed that PSSP self-assembles in water in the form of nanoparticles without the need of any cosolvents. These nanoparticles exhibited number-average hydrodynamic diameter of 120 ± 8 nm with a polydispersity index (PDI) of <0.3, and negatively charged surfaces. We also found out that PSSP nanoparticles can encapsulate and homogeneously distribute a hydrophobic model compound, such as a phthalocyanine dye, Solvent Blue-70 (BL-70), on a metal surface. Collectively, our studies explored and demonstrated the possibility of molecular diversification of biobased starting materials to form amphiphilic nanoparticles with industrially relevant colloidal and surface properties.

Description of Stenotrophomonas sepilia sp. nov., isolated from blood culture of a hospitalized patient as a new member of Stenotrophomonas maltophilia complex

Stenotrophomonas sepilia strain SM16975 (= JCM 32102; = KCTC 62052) is a new species isolated from the blood culture of a hospitalized patient. The biochemical characterization, phenotypic criteria, phylogenomic reconstruction, and genomic analysis were carried out to differentiate it from its phylogenetic neighbours, establishing novel species status in the genus Stenotrophomonas and within Stenotrophomonas maltophilia complex (Smc).

0078 Influence of Light on Brain Activity Upon Waking From Slow Wave Sleep

Introduction

Waking from sleep is associated with reduced alertness due to sleep inertia. Light acutely improves alertness during sleep deprivation. In this study we assessed the influence of light on brain activity and connectivity after waking from slow wave sleep (SWS).

Methods

Twelve participants kept an actigraphy-confirmed stable sleep schedule with 8.5 hours for five nights and five hours for one night prior to an overnight laboratory visit. Participants completed two three-minute Karolinska Drowsiness Tests (KDT) before going to bed at their habitual bedtime. They were monitored continuously using high-density EEG (32-channel; Brain Products GmbH). Participants were woken twice and exposed to red light (0.01 melanopic-lux; control) or blue-enriched light (63.62 melanopic-lux) for one hour, in a randomized order, following at least five minutes of SWS. EEG artifact were removed algorithmically and the spectral composition of each electrode (i.e., fast fourier transform, FFT) and effective connectivity (i.e., partial directed coherence, PDC) between each electrode were estimated. A graphical analysis was conducted to extract features relevant to the facilitation of efficient communication between electrodes. All data were averaged within frequency bins of interest that correspond to delta (1-3Hz), theta (4-7Hz), alpha (8-12Hz), and beta (13-25Hz) bands and expressed relative to the pre-sleep baseline.

Results

Compared to the pre-sleep baseline, participants exposed to blue-enriched light experienced reduced theta and alpha activity; however, these results were not significantly different from the control. In contrast, the communication of frontal electrodes significantly increased across all frequency bands compared to the control, and this effect was most prominent in the alpha (t(11)=3.80, p=.005) and beta bands (t(11)=3.92, p=.004).

Conclusion

Exposure to blue-enriched light immediately after waking from SWS may accelerate the process of waking and help to improve alertness by facilitating communication between brain regions. Future analyses will explore the temporal persistence and granularity of the communicative properties associated with this response.

Support

Naval Postgraduate School Grant. NASA Airspace Operations and Safety Program, System-Wide Safety Project.

Plaque Removal Efficacy of Different Toothbrushes: A Comparative Study

Aim and objective

This study aimed to compare the plaque removal efficacy of different toothbrushes and to ascertain the most efficient mechanical mean for daily plaque removal so as to maintain oral health in a preeminent way.

Study design

It was a randomized controlled clinical trial consisting of 60 subjects divided into three groups (group I ultrasonic and sonic toothbrush, group II multidirectional toothbrush, and group III manual toothbrush) with 20 in each group. Prebrushing and postbrushing plaque scores were recorded at weekly intervals for four weeks using Turesky modification of Quigley and Hein plaque index.

Results

Statistically significant differences (p < 0.001) existed in mean percent reduction of pre-day 1 to pre-day 28 mean percent reduction in plaque values of the ultrasonic toothbrush group (111.92 ± 25.20), the multidirectional toothbrush group (189.06 ± 52.70), and the manual toothbrush group (42.34 ± 14.77). Similar results were found in post-day 1 to post-day 28 mean percent reduction in plaque values.

Conclusion

Group II (i.e., multidirectional toothbrush) showed maximum mean percent reduction in prebrushing and postbrushing plaque scores at the end of four weeks when compared with the baseline values followed by ultrasonic toothbrush and manual toothbrush.

How to cite this article

Aggarwal N, Gupta S, Grover R, et al. Plaque Removal Efficacy of Different Toothbrushes: A Comparative Study. Int J Clin Pediatr Dent 2019;12(5):385-390.

Frontal Polymerization of a Thin Film on a Wood Substrate

Frontal polymerization has been explored as a technique to form two-dimensional thin films (<0.5 mm) on wood. We used trimethylolpropane triacrylate with a thermal free-radical initiator. The viscosity of the resin was adjusted by incorporating fumed silica within the formulation. As filler materials, either calcium carbonate or graphene nanoplatelets was used to evaluate the effect of filler type and content on front propagation. We observed that resin viscosity and film thickness critically affected the qualitative and quantitative propagation of the thermal front resulting in the formation of the coating. A workable coating was formed at a viscosity of 0.6 Pa·s, which was obtained when 3 phr (parts per hundred resin) of fumed silica was used in the resin formulation. Wet film thickness for this resin system was also found to have a limiting value, and full propagation of the front to result in a conformal coating required at least 15 mil (1 mil = 25 μm) of wet film thickness. Filler materials affected film propagation as a function of particle size and thermal properties. While 15 phr calcium carbonate could be incorporated with the resin, only 5 phr graphene nanoplatelets could be loaded within the matrix to ensure complete propagation of the front. Interestingly, for graphene fronts, velocity and temperature reduced systematically as a function of filler content. Filler type and content affected porosity and roughness of the coating, which was quantified by computerized tomography to understand the relationship between porosity and adhesion of the coated film with the wood substrate.

Effect of Different Finishing and Polishing Systems on the Surface Roughness of Resin Composite and Enamel: An In vitro Profilometric and Scanning Electron Microscopy Study

Aim

The aim is to compare and evaluate the different finishing and polishing systems for the change in surface roughness of resin composites and enamel.

Materials and Methods

To conduct the study, 30 extracted human maxillary central incisors were selected, decoronated, and molded in self-cure acrylic molds. A box-shaped cavity of dimensions 3 mm × 3 mm × 2 mm was prepared in all the teeth. A nanohybrid composite resin (Filtek Z250) was then used to restore the prepared cavities. Thirty samples were divided into two groups, control group (Group A, n = 10) and experimental group (Group B, n = 20). The samples in Group A were cured through the Mylar matrix. The experimental group, i.e., Group B was divided into two subgroups, i.e., Subgroup BX, n = 10 in which Sof-Lex polishing system was used for polishing the tooth surface and Subgroup BF, n = 10 in which Shofu composite polishing system was used. The mean surface roughness (Ra in μm) of the composite restoration as well as for the enamel surface of all the samples before and after polishing was measured with a contact profilometer, and the values were correlated with scanning electron microscopy.

Results

The statistical analysis was carried out using paired t-test. The results exhibited a significant decrease in the surface roughness of the resin composite and enamel surface irrespective of the finishing and polishing system used. The mean surface roughness values demonstrated by Mylar matrix was the lowest followed by Sof-Lex polishing system. Shofu polishing system demonstrated the highest surface roughness values.

Conclusion

Finishing and polishing of composite restoration can achieve a surface roughness similar to that of enamel. Involvement of marginal enamel in finishing and polishing procedures carried out for composite restoration results in smoother enamel surface.

Isolated tuberculosis of talus: a case report

Tuberculosis still remains a leading infection, causing death and disability worldwide. We report a patient with isolated tuberculosis of the talus bone. A 14 year old boy reported with an eight-month history of swelling and pain in his left ankle joint. Routine investigations indicated positive aetiology of tuberculous infection . Surgical curettage of the talus and, debridement were performed and a below knee POP cast was applied along with anti TB therapy. After 18 months postoperative , the patient was able to carry out his daily activities without pain .The ankle and foot are rarely affected and account for only 1% of all TB infections. Provisional diagnosis can be made through history and routine investigations but confirmation by the identification of the bacillus from the local lesion or by a histopathological examination of tissue. Talus tuberculosis should be considered in any long standing inflammatory pathology of the ankle.

Role of obturators and other feeding interventions in patients with cleft lip and palate: a review

BACKGROUND

Newborns with cleft palate have a distorted maxillary arch at birth. Depending upon the type of cleft, infants suffer from a variety of problems, many of which are related to feeding difficulties. Feeding these babies is an immediate concern because there is evidence of delayed growth of children with cleft lip and palate (CLCP) compared to normal infants. Many methods have been devised to overcome these problems, including the use of special bottles, nipples, and initial obturator therapy.

REVIEW

A Pub Med search was conducted using the following search terms: feeding interventions in cleft lip and palate, feeding plate/obturator in cleft palate. All the relevant articles were studied and the reference list of selected articles was also studied. Effects of different feeding interventions in infants with cleft palate with special emphasis on obturators, based on descriptive reports, expert opinions, and available data from clinical trials was reviewed.

RESULTS

The combination of search terms generated a list of 74 articles out of which 51 articles were excluded based on analyses of abstracts and full texts. Three additional publications were identified by the manual search. A total of 26 relevant articles were selected which included randomised controlled trials and descriptive studies on feeding interventions and obturators.

CONCLUSION

A single intervention may not fulfil all feeding requirements of infants with CLCP. Combined use of different feeding interventions such as palatal obturator, Haberman feeder, and breast milk pump and lactation education may successfully meet the feeding needs of both mother and child.

In vivo remineralization of artificial enamel carious lesions using a mineral-enriched mouthrinse and a fluoride dentifrice: a polarized light microscopic comparative evaluation

BACKGROUND

Remineralization process is accelerated by the presence of fluoride ions in the oral environment, but this mechanism of caries reversal will be further enhanced if the concentration of calcium, phosphate and fluoride ions is supersaturated with respect to that of oral fluids.

AIM

This in vivo study was carried out to evaluate and compare the remineralizing efficacy of a urea-based mineral-enriched mouthrinse and a fluoridated dentifrice using an in vivo intraoral appliance model and polarized light microscopic evaluation technique.

MATERIALS AND METHODS

The specimens were prepared from sound teeth and artificial caries was produced using an artificial caries medium in vitro and enamel specimens were inserted in removable orthodontic appliances that were to be worn by 14 children of 10-15 years of age. They were divided into three groups - nonfluoridated dentifrice, fluoridated dentifrice and mineral-enriched mouthrinse groups. After the 6-month experimental period, during which the enamel specimens inserted in the intraoral appliance were subjected to one of the agents (either fluoride, nonfluoride dentifrice or mouthrinse) in vivo, the specimens were retrieved from the patients and were evaluated using the polarized light microscopic technique.

OBSERVATIONS AND RESULTS

On analysis, mineral gain occurred in all groups, viz. nonfluoride dentifrice group, fluoride dentifrice and mineral-enriched mouthrinse group. However, it was found to be complete in the mouthrinse group, i.e. both at the surface and at the subsurface (67%), while in the fluoridated dentifrice group, 43% of the samples showed mineral gain in both zones. In the nonfluoridated dentifrice group also, remineralization occurred but was limited either to the surface or the subsurface zone.

CONCLUSIONS

Urea-based mineral-enriched mouthrinse was shown to be more efficacious in the process of remineralization of artificial carious lesions.

A positive feedback-based gene circuit to increase the production of a membrane protein

BACKGROUND

Membrane proteins are an important class of proteins, playing a key role in many biological processes, and are a promising target in pharmaceutical development. However, membrane proteins are often difficult to produce in large quantities for the purpose of crystallographic or biochemical analyses.

RESULTS

In this paper, we demonstrate that synthetic gene circuits designed specifically to overexpress certain genes can be applied to manipulate the expression kinetics of a model membrane protein, cytochrome bd quinol oxidase in E. coli, resulting in increased expression rates. The synthetic circuit involved is an engineered, autoinducer-independent variant of the lux operon activator LuxR from V. fischeri in an autoregulatory, positive feedback configuration.

CONCLUSIONS

Our proof-of-concept experiments indicate a statistically significant increase in the rate of production of the bd oxidase membrane protein. Synthetic gene networks provide a feasible solution for the problem of membrane protein production.

Development of satranidazole mucoadhesive gel for the treatment of periodontitis

The aim of the paper was to develop satranidazole-containing mucoadhesive gel for the treatment of periodontitis. Different mucoadhesive gels were prepared, using various gelling agents like sodium carboxymethylcellulose (SCMC), poloxamer 407, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, and the mucoadhesive polymer carbopol 934P. The selected formulations (based on the mucoadhesive force) were studied for different mechanical properties, such as mucoadhesive strength, hardness, compressibility, adhesiveness, and cohesiveness through Texture Profile Analyzer. In vitro satranidazole release from the prepared formulations was also determined and compared with marketed preparation of metronidazole (Metrogyl gel). The formulation SC30 (containing SCMC 3% w/v) showed maximum mucoadhesive strength (167.72 +/- 3.76 g) and adhesiveness (-46.23 +/- 0.34 N mm), with low hardness (9.81 +/- 0.04 N) and compressibility (40.05 +/- 0.48 N mm) and moderate cohesiveness (0.87 +/- 0.01). SC30 formulation exhibited long-term release. Thus, SC30 gel was evaluated for its clinical effectiveness along with marketed metronidazole gel. At the end of the study (42 days of clinical studies), both formulations were found to significantly reduce the probing depth, plaque index, gingival index, calculus criteria, and bleeding index. However, the SC30 gel was more effective in reducing the above parameters than marketed metronidazole gel. This study confirmed the acceptability and effectiveness of satranidazole gel for treatment of periodontitis.

Inhibition of TNF-alpha-induced cyclooxygenase-2 expression by Mycobacterium bovis BCG in human alveolar epithelial A549 cells

Cyclooxygenase-2 (COX-2) is implicated in pathophysiological processes associated with the initiation or maintenance of host inflammatory responses to infection. Our results demonstrates that Mycobacterium bovis BCG (M. bovis BCG) downregulates tumour necrosis factor-alpha (TNF-alpha)-induced COX-2 gene expression in alveolar epithelial cells by inhibiting the phosphorylations of Raf-1 and p38 kinases. Further, M. bovis BCG-mediated inhibition of COX-2 or p38 mitogen-activated protein kinase could be reversed by Calyculin A, a selective inhibitor of Ser/Thr phosphatases. Moreover, M. bovis BCG inhibited the TNF-alpha-triggered NF-kappaB activation following IkappaB degradation. Taken together, these results suggest that the attenuation of COX-2 expression by vaccine strain, M. bovis BCG, represents a novel strategy to maintain robust host proinflammatory responses to subsequent challenges with virulent tuberculosis bacilli.

Poly-epsilon-caprolactone microspheres and nanospheres: an overview

Poly-epsilon-caprolactone (PCL) is a biodegradable, biocompatible and semicrystalline polymer having a very low glass transition temperature. Due to its slow degradation, PCL is ideally suitable for long-term delivery extending over a period of more than one year. This has led to its application in the preparation of different delivery systems in the form of microspheres, nanospheres and implants. Various categories of drugs have been encapsulated in PCL for targeted drug delivery and for controlled drug release. Microspheres of PCL either alone or of PCL copolymers have been prepared to obtain the drug release characteristics. This article reviews the advancements made in PCL-based microspheres and nanospheres with special reference to the method of preparation of these and their suitability in developing effective delivery systems.

Chitosan microspheres as a potential carrier for drugs

Chitosan is a biodegradable natural polymer with great potential for pharmaceutical applications due to its biocompatibility, high charge density, non-toxicity and mucoadhesion. It has been shown that it not only improves the dissolution of poorly soluble drugs but also exerts a significant effect on fat metabolism in the body. Gel formation can be obtained by interactions of chitosans with low molecular counterions such as polyphosphates, sulphates and crosslinking with glutaraldehyde. This gelling property of chitosan allows a wide range of applications such as coating of pharmaceuticals and food products, gel entrapment of biochemicals, plant embryo, whole cells, microorganism and algae. This review is an insight into the exploitation of the various properties of chitosan to microencapsulate drugs. Various techniques used for preparing chitosan microspheres and evaluation of these microspheres have also been reviewed. This review also includes the factors that affect the entrapment efficiency and release kinetics of drugs from chitosan microspheres.

Intracranial neurothekeoma--a rare parenchymal nerve sheath myxoma of the middle cranial fossa

Neurothekeomas are rare, benign nerve sheath tumors, usually arising from cutaneous nerves in the head and neck region. So far, only 4 cases of the intracranial counterpart have been reported and these were located in the posterior fossa, sellar and parasellar region. We report here the first case of neurothekeoma located deep inside the brain parenchyma. Histologically, the tumor had lobular appearance with bland morphology in spite of cellular pleomorphism, myxoid background and variable S-100 positivity, characteristics of neurothekeomas. The schwannian origin was further confirmed ultrastructurally by demonstrating basal lamina and Luse bodies. Because of its benign nature, the lesion does not need postoperative radiotherapy. Histogenesis of neurothekeoma arising in the parenchyma remains enigmatic. The probable cell of origin could be the Schwann cell or perineurial cell of the nerve twigs around the blood vessels or by extreme differentiation of the precursor cell resting in a suitable microenvironment to the schwannian phenotype.

Gene therapy for brain tumors

"Gene therapy" can be defined as the transfer of genetic material into a patient's cells for therapeutic purposes. To date, a diverse and creative assortment of treatment strategies utilizing gene therapy have been devised, including gene transfer for modulating the immune system, enzyme prodrug ("suicide gene") therapy, oncolytic therapy, replacement/therapeutic gene transfer, and antisense therapy. For malignant glioma, gene-directed prodrug therapy using the herpes simplex virus thymidine kinase gene was the first gene therapy attempted clinically. A variety of different strategies have now been pursued experimentally and in clinical trials. Although, to date, gene therapy for brain tumors has been found to be reasonably safe, concerns still exist regarding issues related to viral delivery, transduction efficiency, potential pathologic response of the brain, and treatment efficacy. Improved viral vectors are being sought, and potential use of gene therapy in combination with other treatments is being investigated.

Relationship between cariogenic diet and dental caries as evaluated from a 5-day diet diary in 4-12 year-old children

A preliminary study was conducted on 50 children in the age group of 4-12 years, who were divided into two groups on the basis of decayed, missing and filled teeth (DMFT) i.e. Group A (1-3) and Group B (> 3). A 5-day diet diary was evaluated and Sweet Score, Total Sugar Exposure, At Meal Sugar Exposures and Between Meal Sugar Exposure were calculated. There was statistically significant difference between the two groups in relation to Sweet Score and Total sugar Exposures. Between Meal Sugar Exposure and At Meal sugar exposure did not differ significantly.