Evaluation of photobiomodulation therapy (PBMT) on salivary flow and composition in head and neck cancer patients undergoing radiation therapy.

OBJECTIVE: Assess the impact of photobiomodulation therapy (PBMT) on xerostomia, salivary flow rate (SFR) and composition in patients undergoing radiotherapy (RT) for head and neck cancer (HNC). STUDY DESIGN: Thirty patients undergoing RT (65 Gy) for HNC were enrolled. Saliva and xerostomia evaluations collected pre- and post-PBMT-RT. PBMT involved irradiation of extra and intraoral points, 15-20 sessions, 2-3 times/week. SFR, trace elements, total protein, alkaline phosphatase, xerostomia, and pH were analyzed. RESULTS: The average age was 60.7 years. After treatment, there was not a significant reduction in SFR and there was no difference on xerostomia. Significant reductions in Al, Cd, Fe, Ni, P, and Sb concentrations were observed, along with a significant increase in Mg concentration. Sample data were organized into 3 groups based on a self-organizing map. Low concentrations of Al, As, Co, Cr, Cu, Fe, Mn, Mo, S, Sr, and Zn were the primary discriminatory factors for group A, while group B consisted of post-PBMT-RT samples with high concentrations of Ca, K, Mg, Na, and S. CONCLUSIONS: PBMT prevented a significant reduction in SFR and xerostomia induced by radiation therapy. These findings suggest that PBMT prevents salivary gland damage minimizing the decline in salivary flow.

Self-organizing map applied to the choice of internal standards for the determination of Cd, Pb, Sn, and platinum group elements by inductively coupled plasma mass spectrometry.

The behaviors of internal standards, according to different flow rates of the cell collision gas (He), were studied for the determination of Cd, Pb, Pd, Pt, Rh, and Sn in samples of fish and mollusks by inductively coupled plasma mass spectrometry (ICP-MS). The elements Bi, Ge, In, Sc, and Y were selected as internal standards, considering their masses and first ionization energies. Addition and recovery experiments were carried out at three concentration levels to evaluate the accuracy of the method applied for the analysis of two samples with different matrices. The results were evaluated using a self-organizing map (SOM). The best analyte/IS pairs were as follows: 114Cd+/74Ge+, 195Pt+/74Ge+, and 208Pb+/74Ge+. For 103Rh+, 106Pd+, and 120Sn+, greater accuracy was achieved without use of an internal standard. Helium gas (2.8 mL min-1) was used in the collision cell for the analytes, except for Sn, and recoveries ranged from 98 to 101% under optimal conditions. The use of SOM as an exploratory analysis tool was an effective approach for selection of the most appropriate internal standards.

Oral health, organic and inorganic saliva composition of men with Schizophrenia: Case-control study.

BACKGROUND: Schizophrenia (SCZ) presents complex challenges related to diagnosis and clinical monitoring. The study of conditions associated with SCZ can be facilitated by using potential markers and patterns that provide information to support the diagnosis and oral health. METHODS: The salivary composition of patients diagnosed with SCZ (n = 50) was evaluated and compared to the control (n = 50). Saliva samples from male patients were collected and clinical parameters were evaluated. The concentration of total proteins and amylase were determined and salivary macro- and microelements were quantified by ICP OES and ICP-MS. Exploratory data analysis based on artificial intelligence tools was used in the investigation. RESULTS: There was a significant increase in the salivary concentrations of Al, Fe, Li, Mg, Na, and V, higher prevalence of caries (p < 0.001), periodontal disease (p < 0.001), and reduced salivary flow rate (p = 0.019) in SCZ patients. Also, samples were grouped into six clusters. As, Co, Cr, Cu, Mn, Mo, Ni, Se, and Sr were correlated with each other, while Fe, K, Li, Ti, and V showed the highest concentrations in the samples distributed in the clusters with the highest association between SZC patients and controls. CONCLUSIONS: The results obtained indicate changes in salivary flow, organic composition, and levels of macro- and microelements in SCZ patients. Salivary concentrations of Fe, Mg, and Na may be related to oral conditions, higher prevalence of caries, and periodontal disease. The exploratory analysis showed different patterns in the salivary composition of SCZ patients impacted by associations between oral health conditions and the use of medications. Future studies are encouraged to confirm the results investigated in this study.

Effect of Genetic Crossing and Nutritional Management on the Mineral Composition of Carcass, Blood, Leather, and Viscera of Sheep.

The effect of genetic crossing and nutritional management on weight gain and the concentration of minerals and trace elements in the carcass, blood, leather, and viscera of sheep were evaluated. Several statistical strategies were used to evaluate the different elemental composition characteristics of pure breed animals, i.e., White Dorper (ODO), Ile de France (OIF), Texel (OTX), and Santa Inês (OSI), as well as their crossbreeds 1/2 White Dorper and 1/2 Santa Inês (ODS), 1/2 Ile de France, and 1/2 Santa Inês (OIS), 1/2 Texel × 1/2 Santa Inês (OTS). Three different diets were evaluated AL (ad libitum), R75, and R63 (75 and 63 g of dry matter/kg of the animal metabolic weight, respectively). Levels of Ca, Cu, Fe, K, Mg, Mn, P, S, and Zn were determined by inductively coupled plasma optical emission spectrometry (ICP OES). The concentration of inorganic elements in the different body components was not affected by the diet (P > 0.05), and OTX and OTS were the breeds with the highest weight gain. Random forest importance models demonstrated that Zn in the carcass, K, Ca, and Zn in blood, and K in leather are most associated with separating the different evaluated sheep's breeds. Crossbreeding the native Santa Inês breed with sheep of exotic breeds produces animals well adapted to confinement.

Potential of near-infrared spectroscopy for quality evaluation of cattle leather.

Models using near-infrared spectroscopy (NIRS) were constructed based on physical-mechanical tests to determine the quality of cattle leather. The following official parameters were used, considering the industry requirements: tensile strength (TS), percentage elongation (%E), tear strength (TT), and double hole tear strength (DHS). Classification models were constructed with the use of k-nearest neighbor (kNN), soft independent modeling of class analogy (SIMCA), and partial least squares-discriminant analysis (PLS-DA). The evaluated figures of merit, accuracy, sensitivity, and specificity presented results between 85% and 93%, and the false alarm rates from 9% to 14%. The model with lowest validation percentage (92%) was kNN, and the highest was PLS-DA (100%). For TS, lower values were obtained, from 52% for kNN and 74% for SIMCA. The other parameters %E, TT, and DHS presented hit rates between 87 and 100%. The abilities of the models were similar, showing they can be used to predict the quality of cattle leather.

Bioaccessibility of Ca, Cu, Fe, Mg, Zn, and crude protein in beef, pork and chicken after thermal processing.

The bioaccessibility of Ca, Cu, Fe, Mg, Zn, and crude protein was evaluated after submitting beef, pork, and chicken to five different thermal treatments. The bioaccessibility of crude protein and metals were simulated by using in vitro enzymatic digestion with a gastric fluid solution and dialysability approach. Inductively coupled plasma optical spectrometry was used to quantify the dialyzable fraction and the total mineral content after microwave-assisted digestion. Graphite furnace atomic absorption spectrometry quantified Cu in chicken dialyzable fraction. The increase of temperature and heat exposure period decreased the protein bioaccessibility. Considering the total and dialyzable fraction, beef is an important source of Cu, Fe, Mg, and Zn to the human diet. The results of Fourier-transform infrared spectroscopy indicated physical changes in the treated samples related to protein denaturation, which was probably responsible for the decreased bioaccessibility of minerals and protein, mainly at higher temperatures.

Effect of root age on the allocation of metals, amino acids and sugars in different cell fractions of the perennial grass Paspalum notatum (bahiagrass).

This work aimed to compare the allocation of Al, Fe, Cu, Ni, amino acids and sugars in different fractions of root cells of Paspalum notatum with 21 and 120 days old grown in quartz sand. In general younger roots showed a higher content of Al, Fe, Cu Ni, amino acids and sugars, compared to older roots. This can be due to a higher metabolic activity of younger roots and/or to structural changes that can occur with cell ageing. Al and Fe were mainly allocated to fractions with pectin, hemicellulose and cellulose, both in younger and older roots. However, older roots also showed a significant fraction of Al allocated to the intracellular fraction. It seems that older roots were less able to prevent the entry of Al in the cytoplasm. The proportion of Cu was higher in intracellular components, both in younger and older roots, as expected from an essential nutrient. Ni content was very low in older roots and in younger roots it was mainly allocated to the intracellular fraction and to the cell wall polysaccharides fraction. The amino acids were mainly allocated to the cytoplasm and polysaccharide fraction. Although younger roots showed a higher total amount of amino acids compared to older roots, the amino acids profile and allocation, mainly in the cytoplasm polysaccharides, was quite similar. Arabinose, a major component of structural glycoproteins of the primary cell wall matrix, was only detected in younger roots. Thus, it seems that root cells of P. notatum suffered changes in the composition of the cell wall components with ageing. To further understand the structural changes of root cells with ageing and its effect on metal allocation, it is important to quantify several components of the cell wall matrix, namely pectins and glycoproteins.

Microwave-assisted digestion procedures for biological samples with diluted nitric acid: identification of reaction products.

Microwave-assisted sample preparation using diluted nitric acid solutions is an alternative procedure for digesting organic samples. The efficiency of this procedure depends on the chemical properties of the samples and in this work it was evaluated by the determination of crude protein amount, fat and original carbon. Soybeans grains, bovine blood, bovine muscle and bovine viscera were digested in a cavity-microwave oven using oxidant mixtures in different acid concentrations. The digestion efficiency was evaluated based on the determination of residual carbon content and element recoveries using inductively coupled plasma optical emission spectrometry (ICP OES). In order to determine the main residual organic compounds, the digests were characterized by nuclear magnetic resonance ((1)H NMR). Subsequently, studies concerning separation of nitrobenzoic acid isomers were performed by ion pair reversed phase liquid chromatography using a C18 stationary phase, water:acetonitrile:methanol (75:20:5, v/v/v)+0.05% (v/v) TFA as mobile phase and ultraviolet detection at 254 nm. Sample preparation based on diluted acids proved to be feasible and a recommendable alternative for organic sample digestion, reducing both the reagent volumes and the variability of the residues as a result of the process of decomposition. It was shown that biological matrices containing amino acids, proteins and lipids in their composition produced nitrobenzoic acid isomers and other organic compounds after cleavage of chemical bonds.

Coconut coir as biosorbent for Cr(VI) removal from laboratory wastewater.

A high cost-effective treatment of sulphochromic waste is proposed employing a raw coconut coir as biosorbent for Cr(VI) removal. The ideal pH and sorption kinetic, sorption capacities, and sorption sites were the studied biosorbent parameters. After testing five different isotherm models with standard solutions, Redlich-Peterson and Toth best fitted the experimental data, obtaining a theoretical Cr(VI) sorption capacity (SC) of 6.3 mg g(-1). Acid-base potentiometric titration indicated around of 73% of sorption sites were from phenolic compounds, probably lignin. Differences between sorption sites in the coconut coir before and after Cr adsorption identified from Fourier transform infrared spectra suggested a modification of sorption sites after sulphochromic waste treatment, indicating that the sorption mechanism involves organic matter oxidation and chromium uptake. For sulphocromic waste treatment, the SC was improved to 26.8+/-0.2 mg g(-1), and no adsorbed Cr(VI) was reduced, remaining only Cr(III) in the final solution. The adsorbed material was calcinated to obtain Cr(2)O(3,) with a reduction of more than 60% of the original mass.

Soil calcium and pH monitoring sensor system.

An agrarian sensorial system based on temperature, moisture, and all solid-state ion-selective potentiometric sensors was developed with the objective of monitoring the behavior of H+ and Ca2+ ions in soil and in real conditions, contributing with a new tool that tries to complement the current precision agriculture technology. The evaluation of the sensorial system to pH monitoring presented a good correlation between the results obtained by the system and the standard methodology, allowing us to notice the soil buffer capacity at different soil depths. With regard to calcium, the sensor system also presented an agreement between its results and those obtained by flame atomic absorption spectrometry, using a calibration model based on multiple linear regressions that allows the correct determination of Ca2+ concentrations in soil depths where the relative moisture is different. In this way, using well-known potentiometric sensors in a complex, discontinued, and heterogeneous matrix, such as soil, the sensorial system proved to be a useful task for agrochemical field applications.

Multivariate classification of cigarettes according to their elemental content determined by inductively coupled plasma optical emission spectrometry.

In this paper we describe our study on the characterization of cigarette samples according to their mineral content. Acid digestion assisted by microwaves was employed, and inductively coupled plasma optical emission spectrometry was the analytical technique used for the determination of Al, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, P and Sr in conventional, light, and flavorized cigarettes. Multivariate techniques, such as hierarchical clusters analysis (HCA) and principal-component analysis (PCA), were applied to discriminate among different types of cigarettes. Cluster analysis and principal-component analysis showed differences in cigarettes according to the type and mineral composition. The cigarette samples were divided within the 3 groups according to their mineral composition. Ca, Sr, Cu, K and Na were the most important elements for cigarette classification, and only these 5 variables were sufficient for the classification and discrimination of the evaluated types of cigarettes.

Determination of vanadium in human hair slurries by electrothermal atomic absorption spectrometry.

This work describes an analytical procedure for vanadium determination in human hair slurries by electrothermal AAS using longitudinal heating (LHGA) and transversal heating (THGA) graphite furnace atomizers. The samples were powdered using cryogenic grinding and the hair slurries containing 0.2% (m/v) were prepared in three different media for determination of vanadium: 0.14molL(-1) HNO(3), 0.1% (v/v) Triton X-100 and 0.1% (v/v) water soluble tertiary amines (CFA-C, pH 8). The limits of detection (LOD), limits of quantification (LOQ), and characteristic masses obtained were 0.28, 0.95mugL(-1) and 35pg (LHGA) and 0.34, 1.13mugL(-1) and 78pg (THGA), respectively. The accuracy of the analytical results obtained by the proposed procedure in both equipments was confirmed by a paired t-test at the 95% confidence level and compared with a conventional procedure based on acid digestion.

A new procedure for bovine milk digestion in a focused microwave oven: gradual sample addition to pre-heated acid.

Milk samples can be efficiently digested using a focused microwave oven, however the conventional procedure of addition of concentrated acids to the liquid sample leads to digestates with elevated acidity and residual carbon concentrations. In this work a focused microwave oven was applied for acid digestion of bovine milk samples using a conventional and an alternative procedure based on gradual sample addition to hot and concentrated acids. A two-level 2(3) full factorial design experiment with eight runs was carried out to evaluate the optimum experimental conditions for reducing both the residual carbon and the final acidity of digestates. The three studied parameters were: temperature of the digestion medium for sample addition, addition of sulfuric acid before the sample or during the first step, and number of aliquots of the sample gradually added. The best conditions were attained by adding small aliquots of milk (ten-fold a volume of 0.5ml added during 5.0min) to a digestion mixture containing 3.0ml nitric acid plus 1.0ml sulfuric acid heated at 105 degrees C. It was demonstrated that the digestion efficiency of the alternative procedure was better than the conventional procedure, i.e. 98 and 80%, respectively. The alternative procedure was applied for determination of Ba, Ca, Cu, K, Mg, Na, P, and Zn in whole and non-fat bovine milk. The accuracy was proved using two certified reference materials (whole and non-fat milk powder).

In-soil potassium sensor system.

A potentiometric sensor system based on potassium ion-selective electrodes was developed for agricultural purposes. Sensors were built using PVC ion-selective membranes over an inner solid contact prepared with graphite-epoxy composites. A copper plate was used as a reference electrode. A two-stage electronic circuit composed of current and voltage amplifiers was designed to interface the sensors to a distributed data acquisition system. Three ion-selective sensors and three off-the-shelf temperature sensors and their associated circuits were mounted in a PVC tube to set up a soil probe. The electronic controls were placed in an airtight box fixed at the upper part of the probe. The system was evaluated in the field, where the sensors presented sensibility within the range of 69-71 mV dec(-)(1). Extracts of soil samples were analyzed by a current flame photometry approach, and the results, compared with the probe measurements, showed a linear relationship (r (2) = 0.992 and 0.995, respectively, to 5 and 20 cm depths), which implies viability and instrumentation reliability for agricultural applications.

Orthophosphate, phytate, and total phosphorus determination in cereals by flow injection analysis.

A flow injection spectrophotometric procedure with enzymatic hydrolysis was developed for determination of orthophosphate, phytate and total phosphorus in cereal samples. Phosphorus species were extracted from cereals with 0.05 mol L(-1) potassium hydrogen phthalate buffer solution at pH 5.7. Orthophosphate was directly determined in the extracts by molybdenum blue spectrophotometric method. The phytate was hydrolyzed by the enzyme phytase coupled to a solid phase packed into an enzymatic reactor, and the resulting hydrolyzed orthophosphate was also determined by spectrophotometry at 650 nm. After optimization for phosphorus species extraction and enzymatic hydrolysis, a linear calibration graph was obtained up to 196 x 10(-6) mol L(-1) orthophosphate (P conc = -2.67 + 0.52x, r = 0.9998). Measurements are characterized by relative standard deviation of 1.6% for a standard of 72 x 10(-6) mol L(-1) orthophosphate and no baseline drift was observed during 4 h operation periods. It provides 72 measurements per hour, with 2.4 x 10(-)6) mol L(-1) and 7.9 x 10(-6) mol L(-1) as detection and quantification limits, respectively.

Direct determination of Cu and Zn in fruit juices and bovine milk by thermospray flame furnace atomic absorption spectrometry.

In the present work, thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) was employed for Cu and Zn determination in bovine milk and fruit juice samples without any pretreatment. TS-FF-AAS system was optimized and a sample volume of 300mul was injected into the carrier stream (0.014moll(-1) HNO(3) at a flow rate of 0.4mlmin(-1)), and it was introduced into a hot Ni tube. The detection limits obtained for Cu and Zn in aqueous solution were 2.2 and 0.91mugl(-1), respectively, and 3.2mugl(-1) for Cu in a medium containing water-soluble tertiary amines. The relative standard deviations varied from 2.7 to 4.2% (n=12). Sample preparation was carried out by simple dilution in water or in water-soluble tertiary amines medium. Accuracy was checked by performing addition-recovery experiments as well as by using reference materials (whole milk powder, non-fat milk powder, and infant formula). Recoveries varied from 97.7 to 105.3% for Cu and Zn. All results obtained for reference materials were in agreement with certified values at a 95% confidence level.

Single vessel procedure for acid vapor partial digestion of bovine liver in a focused microwave: multielement determination by ICP-OES.

An acid vapor partial digestion procedure for bovine liver is proposed using a focused microwave oven and a laboratory-made PTFE support. The support is equipped with three cups of approximately 4 ml volume each one and the cups were adapted to the glass reaction vessel of the microwave oven. A mixture containing HNO(3) plus H(2)SO(4) is heated to 120 degrees C to generate acid vapor. Bovine liver (50-90 mg) were directly weighed into the cups followed by addition of a mixture containing NaClO+H(2)O(2). Samples were exposed to acid vapor during 15-25 min and then diluted with distilled and deionized water to final masses of 3.0 g. Recoveries of Al, Ca, Cu, Fe, Mg, Mn, and Zn were evaluated using an ICP-OES with axially-viewed configuration. The effects of both particle sizes and acid vapor exposure time were evaluated and recoveries of most elements were quantitative when using 25 min of heating and 50 mg of samples. Slightly better recoveries were reached using particles smaller than 44 mum, but this effect was mainly observed for hardly extracted elements such as Al and Fe.

Microwave-assisted Acid decomposition of animal- and plant-derived samples for element analysis.

A single microwave-assisted acid-decomposition procedure is proposed for sample preparation of plant- and bovine-derived materials prior to multielement determination by inductively coupled plasma-optical emission spectrometry (ICP-OES). The procedure involved sample grinding in a cryogenic mill to reduce particle sizes and increase the surface area for acid attack, followed by decomposition under high pressure and temperature. A single heating program was employed and efficiently destroyed most of the organic matrix by using small volumes of nitric acid and hydrogen peroxide. Accuracy of the elemental analysis was indicated by the good agreement between certified and found values of elements in plant and animal samples at 95% confidence level. The sample preparation procedure was fast and reproducible, and proved to be efficient for elemental analysis in agricultural and food-related samples by a sensitive multielement technique such as ICP-OES.