Salivary Gland and Tooth Abnormalities Massively Increase Caries Susceptibility in A Mouse Model of Cleft Lip/Palate

Thesis (Ph.D.)--University of Washington, 2016-04

Triboelectric Effect As A New Strategy For Sealing And Controlling The Flow In Paper-based Devices.

We reported here for the first time that triboelectric charges on PET sheets can be used to seal and control the flow rate in paper-based devices. The proposed method exhibits simplicity and low cost, provides reversible sealing and minimizes the effect of sample evaporation.

Salivary Bpifa1 (splunc1) And Bpifa2 (splunc2 A) Are Modified By Head And Neck Cancer Radiotherapy.

To determine the effects of radiotherapy on salivary BPIFA expression and to investigate the role of BPIFA in the development of known radiotherapy side effects. Unstimulated whole-mouth saliva was collected from 45 cancer patients (1 week before treatment, during the treatment, and 1 week after completion of radiotherapy) and from 20 controls. BPIFA1 and BPIFA2 expression was detected by western blotting and analyzed along with clinicopathologic data and side effects from the radiotherapy. A facial radiation field was associated with lower salivary flow during and after radiotherapy and correlated with side effects, mainly mucositis. Salivary BPIFA1 expression levels were similar between the control group and the patient group before treatment. On the other hand, BPIFA2 levels were higher in the patient group before treatment compared with the control group. BPIFA concentration was modified by radiotherapy as BPIFA1 levels increased (P = .0081) and BPIFA2 decreased (P < .0001). Higher levels of BPIFA1 were associated with the presence of mucositis (P = .0363) and its severity (P = .0500). The present study found that levels of BPIFA1 and glycosylated forms of BPIFA2 are affected by radiotherapy, suggesting that these proteins may play a role in the oral microenvironment in irradiated patients with head and neck cancer.

Analysis of the stimulated whole saliva in overweight and obese school children

OBJECTIVE: To determine if some stimulated whole saliva parameters are influenced by an increase of Body Mass Index. METHODS: Controlled cross-sectional study involving 90 school children of both genders between 7 and 10 years of age, from Bragança Paulista - SP. Three groups were formed: overweight, obese and control. Body Mass Index and diet intake by the Food Register method were evaluated. The salivary pH, flow rate, buffer capacity, protein, phosphate, calcium, fluoride, total and free sialic acid, and peroxidase activity were determined. RESULTS: The overweight and obese groups showed greater energy and lipid intake (P< 0.001) than the control group. There was no difference in the saliva flow rate between groups, however only the control group showed a mean value considered normal. In the overweight and obese groups a decrease in both the concentration of phosphate (P< 0.001) and peroxidase activity (P<0.001) was observed. In the obese group an increase in the concentrations of free sialic acid (P= 0.004) and protein (P= 0.003) occurred. CONCLUSION: Overweight and obese children show alterations in the concentrations of phosphate, free sialic acid and proteins, and in the peroxidase activity that are favorable conditions for dental caries.

Electrochemical degradation of the dye reactive orange 16 using electrochemical flow-cell

Electrochemical removals of color and organic load from solutions containing the dye reactive orange 16 (RO16) were performed in an electrochemical flow-cell, using a platinum working electrode. The influence of the process variables flow-rate, such as NaCl concentration, applied potential and solution pH, were studied. The best color removal achieved was 93% (λ = 493 nm) after 60 min at 2.2 V vs. RHE electrolysis, using 1.00 g L-1 NaCl as supporting electrolyte. The rises in the concentration of NaCl and applied potential increased the color removal rate. The best total organic carbon removal (57%) was obtained at 1.8 V, without the separating membrane, indicating that the ideal conditions for the color removal are not necessarily the same as those to remove the total organic carbon. The degradation efficiency decreased with the solution pH decrease.

Evaluation of a simple hyphenated system for flow injection solid-phase pre-concentration and capillary electrophoresis

In this work, the development and evaluation of a hyphenated flow injection-capillary electrophoresis system with on-line pre-concentration is described. Preliminary tests were performed to investigate the influence of flow rates over the analytical signals. Results revealed losses in terms of sensitivity of the FIA-CE system when compared to the conventional CE system. To overcome signal decrease and to make the system more efficient, a lower flow rate was set and an anionic resin column was added to the flow manifold in order to pre-concentrate the analyte. The pre-concentration FIA-CE system presented a sensitivity improvement of about 660% and there was only a small increase of 8% in total peak dispersion. These results have confirmed the great potential of the proposed system for many analytical tasks especially for low concentration samples.

Determination of paracetamol at a graphite-polyurethane composite electrode as an amperometric flow detector

A bare graphite-polyurethane composite was evaluated as an amperometric flow injection detector in the determination of paracetamol (APAP) in pharmaceutical formulations. A linear analytical curve was observed in the 5.00 x 10-5 to 5.00 x 10-3 mol L-1 range with a minimum detectable net concentration of 18.9 µmol L-1 and 180 determinations h-1, after optimization of parameters such as the detection potential, sample loop volume, and carrier solution flow rate. Interference of ascorbic acid was observed, however, it was possible overcome the interference, reaching results that agreed with HPLC within 95% confidence level. These results showed that the graphite-polyurethane composite can be used as an amperometric detector for flow analysis in the determination of APAP.

Syndromes with salivary dysfunction predispose to tooth wear: case reports of congenital dysfunction of major salivary glands, Prader-Willi, congenital rubella, and Sjogren's syndromes.

Four cases-of congenital dysfunction of the major salivary glands as well as of Prader-Willi, congenital rubella, and Sjogren's syndromes-were identified in a series of 500 patients referred for excessive tooth wear. Although there was evidence of consumption of highly acidic drinks, some occlusal parafunction, and unacceptable toothbrushing habits, salivary dysfunction was the salient factor predisposing a patient to tooth wear in these syndromal cases. The 500 subjects have been characterized either as having medical conditions and medications that predispose them to xerostomia or lifestyles in which workplace- and sports-related dehydration lead to reduced salivary flow. Normal salivation, by buffering capacity, clearance by swallowing, pellicle formation, and capacity for remineralization of demineralized enamel, protects the teeth from extrinsic and intrinsic acids that initiate dental erosion. Thus, the syndromes, unrelated in many respects, underline the importance of normal salivation in the protection of teeth against tooth wear by erosion, attrition, and abrasion.

The oral medicine of tooth wear

This review illustrates, through a series of case histories, how oral medicine insights aid the diagnosis and management of patients with excessive tooth wear. The cases reviewed are drawn from the records of 500 southeast Queensland patients referred to the author over a 12 year period. Patients most at risk of dental erosion have work and sports dehydration, caffeine addiction, gastro-oesophageal reflux, asthma, diabetes mellitus, hypertension or other systemic diseases or syndromes that predispose to xerostomia. Saliva protects the teeth from the extrinsic and intrinsic acids which cause dental erosion. Erosion, exacerbated by attrition and abrasion, is the main cause of tooth wear. These cases illustrate that teeth, oral mucosa, salivary glands, skin and eyes should be examined for evidence of salivary hypofunction and attendant medical conditions. Based on comprehensive oral medicine, dietary analyses and advice, it would seem patients need self-management plans to deal with incipient chronic tooth wear. The alternative is the expensive treatment of pain, occlusal damage and pulp death required to repair the effects of acute severe tooth wear.

Unsaturated liquid percolation flow through nonwetted packed beds

The unsaturated flow of liquid through packed beds of large particles was studied using six different liquids, all with contact angles greater than 90degrees on the bed packing (wax spheres of 9, 15 and 19.4 mm diameter). The liquid flow was discrete in nature, as drops for low flow rates and rivulets for high flow rates. For unsaturated liquid flows, the actual percolation velocity, not superficial velocity, should be used to characterize the flow. The percolation velocity did not vary with packed-bed depth, but was a strong function of liquid flow rate, liquid and particle properties. Effects of liquid and particle properties (but not flow rate) are well captured by a simple correlation between the liquid-particle friction factor and Reynolds number based on actual percolation velocities. Liquid dispersion, characterized by the maximum dispersion angle, varies significantly with liquid and particle properties. The tentative correlation suggested here needs further validation for a wider range of conditions.

Determination of polyphenols in wines by reaction with 4-aminoantipyrine and photometric flow-injection analysis

A new flow-injection analytical procedure is proposed for the determination of the total amount of polyphenols in wines; the method is based on the formation of a colored complex between 4-aminoantipyrine and phenols, in the presence of an oxidizing reagent. The oxidizing agents hexacyanoferrate(III), peroxodisulfate, and tetroxoiodate(VII) were tested. Batch trials were first performed to select appropriate oxidizing agents, pH, and concentration ratios of reagents, on the basis of their effect on the stability of the colored complex. Conditions selected as a result of these trials were implemented in a flow-injection analytical system in which the influence of injection volume, flow rate, and reaction- coil length, was evaluated. Under the optimum conditions the total amount of polyphenols, expressed as gallic acid, could be determined within a concentration range of 36 to 544 mg L–1, and with a sensitivity of 344 L mol–1 cm–1 and an RSD <1.1%. The reproducibility of analytical readings was indicative of standard deviations <2%. Interference from sugars, tartaric acid, ascorbic acid, methanol, ammonium sulfate, and potassium chloride was negligible. The proposed system was applied to the determination of total polyphenols in red wines, and enabled analysis of approximately 55 samples h–1. Results were usually precise and accurate; the RSD was <3.9% and relative errors, by the Folin–Ciocalteu method, <5.1%.

Study of the voltammetric behaviour of metam and its application to an amperometric flow system

The electrochemical behaviour of the pesticide metam (MT) at a glassy carbon working electrode (GCE) and at a hanging mercury drop electrode (HMDE) was investigated. Different voltammetric techniques, including cyclic voltammetry (CV) and square wave voltammetry (SWV), were used. An anodic peak (independent of pH) at +1.46 V vs AgCl/Ag was observed in MTaqueous solution using the GCE. SWV calibration curves were plotted under optimized conditions (pH 2.5 and frequency 50 Hz), which showed a linear response for 17–29 mg L−1. Electrochemical reduction was also explored, using the HMDE. A well defined cathodic peak was recorded at −0.72 V vs AgCl/ Ag, dependent on pH. After optimizing the operating conditions (pH 10.1, frequency 150 Hz, potential deposition −0.20 V for 10 s), calibration curves was measured in the concentration range 2.5×10−1 to 1.0 mg L−1 using SWV. The electrochemical behaviour of this compound facilitated the development of a flow injection analysis (FIA) system with amperometric detection for the quantification of MT in commercial formulations and spiked water samples. An assessment of the optimal FIA conditions indicated that the best analytical results were obtained at a potential of +1.30 V, an injection volume of 207 μL and an overall flow rate of 2.4 ml min−1. Real samples were analysed via calibration curves over the concentration range 1.3×10−2 to 1.3 mg L−1. Recoveries from the real samples (spiked waters and commercial formulations) were between 97.4 and 105.5%. The precision of the proposed method was evaluated by assessing the relative standard deviation (RSD %) of ten consecutive determinations of one sample (1.0 mg L−1), and the value obtained was 1.5%.

PulseCath iVAC 3LTM hemodynamic performance for simple assisted flow.

The PulseCath iVAC 3L? left ventricular assist device is an option to treat transitory left heart failure or dysfunction post-cardiac surgery. Assisted blood flow should reach up to 3 l/min. In the present in vitro model exact pump flow, depending on various frequencies and afterload was examined. Optimal flow was achieved with inflation/deflation frequencies of about 70-80/min. The maximal flow rate was achieved at about 2.5 l/min with a minimal afterload of 22 mmHg. Handling of the device was easy due to the connection to a standard intra-aortic balloon pump console. With increasing afterload (up to a simulated mean systemic pressure of 66 mmHg) flow rate and cardiac support are in some extent limited.

Right coronary artery flow velocity and volume assessment with spiral K-space sampled breathhold velocity-encoded MRI at 3 tesla: accuracy and reproducibility.

PURPOSE: To evaluate accuracy and reproducibility of flow velocity and volume measurements in a phantom and in human coronary arteries using breathhold velocity-encoded (VE) MRI with spiral k-space sampling at 3 Tesla. MATERIALS AND METHODS: Flow velocity assessment was performed using VE MRI with spiral k-space sampling. Accuracy of VE MRI was tested in vitro at five constant flow rates. Reproducibility was investigated in 19 healthy subjects (mean age 25.4 +/- 1.2 years, 11 men) by repeated acquisition in the right coronary artery (RCA). RESULTS: MRI-measured flow rates correlated strongly with volumetric collection (Pearson correlation r = 0.99; P < 0.01). Due to limited sample resolution, VE MRI overestimated the flow rate by 47% on average when nonconstricted region-of-interest segmentation was used. Using constricted region-of-interest segmentation with lumen size equal to ground-truth luminal size, less than 13% error in flow rate was found. In vivo RCA flow velocity assessment was successful in 82% of the applied studies. High interscan, intra- and inter-observer agreement was found for almost all indices describing coronary flow velocity. Reproducibility for repeated acquisitions varied by less than 16% for peak velocity values and by less than 24% for flow volumes. CONCLUSION: 3T breathhold VE MRI with spiral k-space sampling enables accurate and reproducible assessment of RCA flow velocity.

A prospective study of salivary gland function in patients undergoing radiotherapy for squamous cell carcinoma of the oropharynx

Résumé: Le traitement du cancer avancé de la tête et du cou nécessite souvent une approche multidisciplinaire associant la chirurgie, la radiothérapie et la chimiothérapie. Chacun de ces traitements présente des avantages, des limites et des inconvénients. En raison de la localisation de la tumeur primaire et/ou des métastases ganglionnaires, les glandes salivaires majeures sont fréquemment touchées par les traitements oncologiques. La salive joue un rôle déterminant dans la cavité buccale car elle lubrifie les tissus et facilite à la fois la déglutition et l'élocution. Son contenu en électrolytes et en protéines, dont certaines possèdent un effet antibactérien, protège les dents de la déminéralisation par l'acidité. Une fonction normale, liée autant à la quantité qu'à la qualité de la salive, reste indispensable pour le maintien d'une bonne santé buccale. L'objectif de cette étude prospective a été de déterminer, dans un groupe homogène de patients, l'influence d'un traitement de radiothérapie sur divers paramètres salivaires comme la sécrétion, le pH et l'effet tampon, avant, pendant et jusqu'à un an après la fin du traitement. L'étude a aussi examiné le comportement de ces paramètres salivaires après une intervention chirurgicale seule au niveau de la tête et du cou, avec ou sans exérèse d'une glande sous- maxillaire. L'étude s'est basée sur 54 patients (45 hommes et 9 femmes) atteints d'un carcinome épidermoïde avancé avec une localisation oro-pharyngée confirmée (n = 50) ou soupçonnée (n = 4), adressés et investigués dans le Centre Hospitalier Universitaire Vaudois de Lausanne, Suisse. Tous ces patients furent traités par radiothérapie seule ou en combinaison avec une chirurgie et/ou une chimiothérapie. Trente-neuf des 54 patients parvinrent à la fin de cette étude qui s'est étendue jusqu'à 12 mois au-delà de la radiothérapie. La chirurgie de la tête et cou, en particulier après ablation de la glande sous-maxillaire, a révélé un effet négatif sur la sécrétion salivaire. Elle n'influence en revanche ni le pH, ni l'effet tampon de la salive. Cependant, l'effet sur la sécrétion salivaire lié à la chirurgie est progressivement masqué par l'effet de la radiothérapie et n'est plus identifiable après 3-6 mois. Dès le début de la radiothérapie, la sécrétion salivaire chût très manifestement pour diminuer progressivement jusqu'à 1/3 de sa capacité à la fin du traitement actinique. Une année après la fin de cette radiothérapie, la dysfonction salivaire est caractérisée par une diminution moyenne de la sécrétion salivaire, de 93 % (p < 0,0001) pour la salive au repos et de 95 % (p < 0.0001) pour la salive stimulée, par rapport aux valeurs pré-thérapeutiques. Le pH salivaire ainsi que l'effet tampon furent également influencés par le traitement actinique. L'effet tampon a présenté une diminution à 67 % à une année post-traitement en comparaison de sa valeur pré-thérapeutique. Le pH de la salive stimulée présente une légère, mais significative, diminution par rapport à sa valeur antérieure à la radiothérapie. En conclusion, la chirurgie des cancers de l'oropharynx précédant une radiothérapie a une influence négative sur la sécrétion salivaire sans aggraver l'hyposialie consécutive aux radiations ionisantes. Cette étude confirme qu'un traitement oncologique comprenant une irradiation totale des glandes salivaires majeures chez des patients atteints d'un carcinome épidermoïde avancé de la région oro-pharyngée, induit une perte sévère et à long terme de la sécrétion salivaire avec une altération du pH et de l'effet tampon Abstract: Objective. We sought to investigate the impact of head and neck cancer treatment on salivary function. Study design. The study was conducted on 54 patients with advanced squamous cell carcinoma with confirmed (n =50) or suspected (n = 4) primary oropharyngeal localization who were treated with radiation alone or in combination with surgery or chemotherapy, or both. The following groups were considered in the evaluation: 1, the entire pool of patients; 2, those undergoing surgery and those not undergoing surgery before radiation; 3, those undergoing resection and those not undergoing resection of the submandibular gland. The flow rates, pH, and buffering capacity were determined before, during, and up to 12 months after the completion of radiation. Results. Head and neck surgery, particularly when submandibular gland resection was performed, had a negative impact on salivary flow rates but did not influence pH or buffering capacity. Nonetheless, the effect of surgery on salivary flow rates decreased progressively and disappeared at 3 to 6 months after radiotherapy. More than two thirds of the salivary output was lost during radiation treatment. All patients were experiencing salivary dysfunction at 1 year after completion of radiotherapy, with average decreases of 93% (P < .0001) and 95% (P < .0001) for whole resting salivary flow and whole stimulated salivary flow, respectively, compared with the preradiotherapy values. The buffering capacity decreased to 67% of its preradiotherapy value, and whole stimulated saliva became acidic. Conclusions. The result of this study confirms that cancer treatment involving full-dose radiotherapy (RTH) to all major salivary glands for locally advanced squamous cell carcinoma of the oropharynx induces severe hyposalivation with alteration of salivary pH and buffering capacity. Head and neck surgery has a negative impact on salivary flow rates, especially when the submandibular gland is removed. However, surgery before irradiation is not a factor aggravating hyposalivation when postoperative radiotherapy includes all the major salivary glands.