Hanna Instruments Research Articles

Validation of a portable, waterproof blood pH analyser for elasmobranchs.

Quantifying changes in blood chemistry in elasmobranchs can provide insights into the physiological insults caused by anthropogenic stress, and can ultimately inform conservation and management strategies. Current methods for analysing elasmobranch blood chemistry in the field are often costly and logistically challenging. We compared blood pH values measured using a portable, waterproof pH meter (Hanna Instruments HI 99161) with blood pH values measured by an i-STAT system (CG4+ cartridges), which was previously validated for teleost and elasmobranch fishes, to gauge the accuracy of the pH meter in determining whole blood pH for the Cuban dogfish (Squalus cubensis) and lemon shark (Negaprion brevirostris). There was a significant linear relationship between values derived via the pH meter and the i-STAT for both species across a wide range of pH values and temperatures (Cuban dogfish: 6.8-7.1 pH 24-30°C; lemon sharks: 7.0-7.45 pH 25-31°C). The relative error in the pH meter's measurements was ~±2.7%. Using this device with appropriate correction factors and consideration of calibration temperatures can result in both a rapid and accurate assessment of whole blood pH, at least for the two elasmobranch species examined here. Additional species should be examined in the future across a wide range of temperatures to determine whether correction factors are universal.

Effect of Chlorhexidine with Fluoride Mouthrinse on Plaque Accumulation, Plaque pH - A Double Blind Parallel Randomized Clinical Trial.

Mouthwashes are important means used in chemical control of dental plaque. There is strong evidence suggestive of better effectiveness, when fluoride is added to chlorhexidine mouthwash. To assess the anti-plaque efficacy of Chlorhexidine combined with Fluoride mouthwash and to measure its impact on plaque accumulation and on plaque pH. Initially 100 subjects were screened. A double blind, parallel randomized clinical trial was conducted on 30 subjects after applying inclusion and exclusion criteria. Other independent variables were matched before randomly allocating them in three groups: Group A-Chlorhexidine as positive control, Group B-Chlorhexidine + Fluoride as test group and Group C- Distilled water as negative control. Oral prophylaxis of participants was done before onset of the study. Plaque pH was assessed before and immediately after rinsing at 0, 5 and 10 minutes interval and after 7 days with digital pH electrode (pHepR pH meter, Hanna Instruments R10285) and accumulation of plaque was recorded by Turesky et al., modification of Quigley Hein Plaque Index (1970). ANOVA test was used for statistical analysis. Although there was a statistically significant reduction in mean plaque scores from baseline to seven days in both Groups A and B, Group B showed better anti-plaque efficacy . Almost equal drop in plaque pH was seen for both the groups at 5 and 10 minutes. Better anti-plaque efficacy was observed in Group B (Chlorhexidine and Fluoride combination) with minimum variation of plaque pH.

In Vitro Liberation of Indomethacin from Chitosan Gels Containing Microemulsion in Different Dissolution Mediums

The objective of this research is to outline the liberation of indomethacin from different chitosan gels containing O/W microemulsion. The influence of surfactant, sodium lauryl sulfate, in two concentrations (0.5% and 0.75%, w/w) was determined in dissolution medium on the release of indomethacin, which was used as poor water-soluble model drug. Chitosan gels were prepared in four different concentrations of chitosan-1%, 1.5%, 2%, and 3% (w/w). Microemulsion enhanced the liberation of the indomethacin from chitosan gels into all dissolution mediums. Adding the surfactant into phosphate-buffered saline decreased the amount of liberated indomethacin from microemulsion, gel mixture, but increased the drug liberation from pure chitosan gels. It was detected that with the increased concentration of chitosan in the samples, the amount of indomethacin liberated (p < 0.05) also increased. A conclusion was drawn that the liberation of indomethacin from chitosan gels was influenced by increased pH of the samples. The high viscosity induced a higher release of indomethacin from 3% (w/w) chitosan hydrogel at pH 5.8 as compared with 3% (w/w) chitosan hydrogel at pH 3.8. The highest percentage of released indomethacin was determined when a mixture of microemulsion gel with higher chitosan content was used.

The Lantibiotic NAI-107 Binds to Bactoprenol-bound Cell Wall Precursors and Impairs Membrane Functions

The lantibiotic NAI-107 is active against Gram-positive bacteria including vancomycin-resistant enterococci and methicillin-resistant Staphylococcus aureus. To identify the molecular basis of its potency, we studied the mode of action in a series of whole cell and in vitro assays and analyzed structural features by nuclear magnetic resonance (NMR). The lantibiotic efficiently interfered with late stages of cell wall biosynthesis and induced accumulation of the soluble peptidoglycan precursor UDP-N-acetylmuramic acid-pentapeptide (UDP-MurNAc-pentapeptide) in the cytoplasm. Using membrane preparations and a complete cascade of purified, recombinant late stage peptidoglycan biosynthetic enzymes (MraY, MurG, FemX, PBP2) and their respective purified substrates, we showed that NAI-107 forms complexes with bactoprenol-pyrophosphate-coupled precursors of the bacterial cell wall. Titration experiments indicate that first a 1:1 stoichiometric complex occurs, which then transforms into a 2:1 (peptide: lipid II) complex, when excess peptide is added. Furthermore, lipid II and related molecules obviously could not serve as anchor molecules for the formation of defined and stable nisin-like pores, however, slow membrane depolarization was observed after NAI-107 treatment, which could contribute to killing of the bacterial cell.

Comparison of the trace metal concentration of drinking water supply options in southwest coastal areas of Bangladesh

In the coastal areas of Bangladesh, scarcity of drinking water is acute as the fresh water aquifers at reasonable depths are not available and surface water is highly saline. Households are mainly dependent on rainwater harvesting, pond sand filter (PSF), and rain-fed pond water for drinking purposes. To ascertain the water quality for human consumption, chemical parameters such as pH, conductivity and the concentrations of calcium, magnesium, iron, manganese, copper, zinc, lead, chromium, cadmium, nickel and arsenic were evaluated in the alternative drinking water supply options employed in the southwest coastal areas of Bangladesh. An inductively coupled plasma-optical emission spectroscopy was used for determination of trace metal concentrations. pH and conductivity were measured using HANNA Instrument. The mean iron and manganese concentrations for rain-fed pond and PSF water were much higher than harvested rainwater. The iron concentrations for 41 % of the pond water samples were higher than the Bangladesh guideline value. Iron and manganese removal by PSFs was found to be 74 and 51 %, respectively. Scarcity of calcium and magnesium were found in harvested rainwater. Furthermore, one pond water sample showed arsenic concentration above the 10 μg/l WHO drinking water guideline. The presence of an elevated iron and manganese and low calcium and magnesium concentrations in the drinking water could be a matter of public health concern.

The Study of Water Quality of Several Local Sources

Abstract Aim: The aim of this study is to analyze the water quality of several local sources from the Toplița-Deda region, as well as from the Gheorgheni basin, in order to inform the population about the water quality and about the importance of the drinking water control. Method: Repeated water samples were collected from a total number of 41 sources in the two studied regions during 2010. A multiparametric colorimeter, Hanna Instruments C99 was used to determine certain physical and chemical parameters. A number of current and specific microbiological analyses were also carried out. Results: The average values and the percentage of the positive samples with values above permitted limits were calculated. The highest accepted levels were based on Law no. 458/2002 regarding drinkable water quality. Among the mineral indicators iron exceeded the limit in 18.18% and water samples were poor in fluoride (83.65%) and in iodine (98.18%). A small percentage of sources (3.63%) indicated pollution, 10.9% had high nitrate level. Analyzing the microbiological content, our water samples were within the drinkability limits required by law. Conclusion: Our study emphasizes the importance of monitoring water supplies, the awareness of the water quality according to mineral composition, pollution estimation and microbiological characteristics in order to prevent the unexpected influence on the health status of the consumer population.

Assessment the Present Status of Batticaloa Lagoon, Sri Lanka by means of Water Quality, Fish Diversity Indices and Pollution Indicating Planktons

Abiotic and biotic variables of coastal lagoons are highly heterogeneous in both space and time, and this heterogeneity complicates the assessment of lagoon ecological status. These variables are essential for monitoring and preserving of these fragile ecosystems and the resources and services they sustain. This study was designed to assess the effect of lagoon water quality on changes in fish abundance. In situ measurements of chemical and physical parameters of the Batticaloa lagoons were measured fortnightly by using a calibrated portable Hanna instruments over the different seasons from March 2012 to February 2013. Fish diversity indices for the main commercial species were calculated. Fish composition varied greatly according to the study site and the seasonal trends. Results reveal that the existing conditions, such as salinity dissolved oxygen, nitrate and pH had a strong effect on the fish community in the lagoon. The present study is commissioned to assess the seasonal variation and the status of the lagoon to make informed plans for the fishery of the lagoon patients to reap it successfully and sustainably.

The comparison study of Fluoride kinetics in saliva after the use of chewing gums containing different fluoride compounds In Iraqi subjects

There is a relationship between the use of fluoride, the reduction of dental caries and the increase of dental fluorosis. The purpose of this study was to analyze the fluoride kinetics in saliva after using two commercially available chewing gums with fluoride, which contains (3.38) mg of fluoride as marketed Sodium monofluorophosphate (NaMFP) and sodium fluoride (NaF) which are the two most common sources of fluoride used in currently fluoride dentifrices.Fifteen 7-9 year-old volunteers were instructed to chew the fluoridated gums. Total saliva was collected, at 0, 3, 6, 9 and 15 minutes after 3 minutes starting chewing. Salivary fluoride was analyzed with a fluoride-specific electrode (201 Fluoride E. HANNA instruments) after acid hydrolysis.The fluoride amount in the saliva samples after the use of chewing gum which contains Sodium monofluorophosphate (NaMFP) was 0.4 mg which higher than after the use of chewing gum contains sodium fluoride (NaF) which was 0.041mg in all experimental periods, The high fluoride presence in saliva after the use of chewing gum of (NaMFP) is significant to prevent dental caries and this should be evaluated in clinical researches. On the other hand, children at an age of risk for dental fluorosis should avoid the use of this kind of chewing gums.

Evaluation of rapid analysis systems for on-farm nitrate analysis in vegetable cropping

Small analytical systems enabling rapid on-farm analysis may be useful for monitoring crop and soil nutrient status. Two commercially available, rapid analysis systems were evaluated for analysis of (NO3-) in aqueous standard solutions (AS), and in soil solution (SS), plant sap (PS) and fertigation nutrient solutions (NS) obtained from tomato crops. The systems were the Merck RQFlex reflectometer and the Hanna Instruments C115 Grow Master colorimeter. (NO3-) in AS covered the analytical range of each instrument, being 0.3-3.2 and 0.3-16.1 mmol/L, respectively, for the reflectometer and colorimeter. (NO3-) were 5-14 mmol/L for SS, 2.3-33 mmol/L for NS, and 63-158 mmol/L for PS. Accuracy was evaluated using linear regression against (1) known concentration for AS, and (2) laboratory analysis for SS, PS and NS. For the reflectometer with AS, SS and PS, the linear regression had slopes of 1 +/ - 0.08 and intercepts of /= 0.94. The reflectometer was generally accurate for all media examined; it was rapid (1 min per analysis) and simple to use. The colorimeter was generally similarly accurate; however, it was slower, required reagent preparation and was subject to colour interferences. This work demonstrated that the reflectometer can provide rapid and accurate on-farm measurement of (NO3-) in SS, PS and NS.

Heritability and Variance Component Estimates of Meat Quality in Japanese Quail (Coturnix coturnix japonica)

A comparison of 3 methods for variance component estimation to compute the heritability of meat quality characteristics (body weight, breast meat weight, breast yield, l, a, b, c, h, and ph) was performed using the methods of maximum likelihood (ML), restricted maximum likelihood (REML), and minimum variance quadratic unbiased estimator (MIVQUE). The parent population was set up at random from a closed population of Japanese quail (Coturnix coturnix japonica). Selection was not applied for any productive characteristics and no special care was taken to avoid inbreeding. After 12-h feed withdrawal, the birds were weighed and slaughtered at 35 days of age. Their carcasses were dissected. Then 24-h postmortem and breast meat (pectoralis major and pectoralis minor) weights (BRW) were measured. Ultimate pH values (pHu) of the left breast meat were measured with a pH meter (Hanna Instrument Model 8314) using a penetration electrode (FC-200) after 24 h post-mortem. Color measurements (brightness ´´l´´, redness ´´a´´, yellowness ´´b´´, chroma ´´c´´, and hue ´´h´´) of the left breast meat were carried out using a Minolta CM508d spectrocolorimeter connected to a computer. Heritabilities of meat quality characteristics estimated by maximum likelihood (ML), restricted maximum likelihood (REML) and minimum variance quadratic unbiased estimation (MIVQUE) ranged from moderate to high.

An assessment of the validity of enteral aspirate pH measurements made with commercial pH strips

Summary Background & aims Clinicians must ensure that enteral feeding tubes are in the correct position prior to use. Malposition of enteral feeding tubes into the trachea resulting in respiratory distress or death has been described in the literature. pH strips can be used to determine tube position; however, commercially available pH strips are industrial in nature and not intended for clinical use. Therefore, institutions have a requirement for clinically validated pH strips. The aim of this study is to compare the accuracy of commercially available pH strips ranges 0–6 and 2–9 (Merck Serono, UK) to a calibrated pH meter (pH 211 Microprocessor, Hanna Instruments) for the assessment of enteral aspirate. Methods Forty-eight patients were included in the study; some patients had an aspirate taken on more than one occasion. A total of 60 measurements were attempted. In 6 cases the investigators failed to obtain an aspirate, therefore 54 aspirates were analysed in total. Each aspirate obtained was analysed by both pH strips and a calibrated pH meter. Results These data show a high correlation between the pH strips (both 0–6 and 2–9) and the pH meter, with r-values (Pearson's correlation) approaching 1 in all cases. Conclusions We conclude that Merck Serono pH strips accurately reflect the actual pH of enteral aspirate when compared to a calibrated pH meter. They may therefore be useful in the placement of feeding tubes and in the determination of feeding tube position in the stomach and small bowel.

Physical characteristics of Longissimus lumborum muscle of “Sarda” and “Nero Siciliano” pigs reared outdoor. Preliminary results

It is known that the sensory properties, i.e. smell, taste, colour, juiciness, texture and tenderness represent the principal factors able to condition drastically the choices of the consumers at the moment of purchase, therefore, they have a role of primary importance regarding the qualification of the product. The physical characteristics of the meat are influenced by different factors such as: age, sex, breed, breeding system and transport, slaughtering and ripeness; the aim of this study was to evaluate some physical characteristics of pig meat derived from two different autochthonous Italian genetic types. The trial was carried out on 30 castrated males pigs, 15 Sarda and 15 Nero Siciliano, reared outdoor respectively in the Ogliastra (Sardinia-Italy) and in the Nebrodi (Sicily-Italy) mountain area at 550±50 m above sea level. Animals fed spontaneous fruits, acorn principally, of undergrowth variable in relation to the seasons. In March 2006, at the age of 2 years and live weight of 106.4±4.2 kg for the Sarda and 107.2±3.6 kg for the Nero Siciliano, the pigs were slaughtered. At 45’ post mortem the pH1 value of each half-carcass was determined (Hanna Instrument HI 9023). After 24 hours of refrigeration at 4° C from the right half-carcass of each animal, one sample of Longissimus lumborum muscle (L2-L5) was taken and the pHu, Colour (CIEL*a*b* system; Minolta CR – 400), Cooking loss and Warner-Bratzler shear force (INSTRON 5542) analysed.Data were subjected to the statistical analysis of variance by the GLM procedure of SAS. The pH1 (Sarda 6.07 vs. Nero Siciliano 6.06; P=0.29) and pHu (Sarda 5.98 vs. Nero Siciliano 5.45; P=0.06) values indicate a bad progress of meat acidification for the Sarda pigs; this could be due to the typical extensive breeding system of these animals, therefore to the difficulties of their capture and transportation to the slaughterhouse. Significant differences were observed for the colour parameters of the meat with the lowest values of L* (Sarda 39.91 vs. Nero Siciliano 50.88; P=0.001), a* (Sarda 11.21 vs. Nero Siciliano 15.70; P=0.001), b* (Sarda 4.03 vs. Nero Siciliano 4.63; P=0.031) and Chroma (Sarda 11.85 vs. Nero Siciliano 16.39; P=0.001) in the Sarda pigs; these data are related to the highest pHu values. The Cooking loss has shown no significant differences between two genetic types (Sarda 27.79% vs. Nero Siciliano 27.80%; P=0.50). As regards the tenderness, the values of WBS (Sarda 4.29 kg f/cm2 vs. Nero Siciliano 3.57 kg f/cm2; P=0.02) were significantly lowest in the meat of Nero Siciliano pigs, in relation to the best acidification of the muscle of these animals, testifying a meat more tender than that of Sarda pigs. Data show that, for improving the meat quality and its aptitude to the transformation, it need to modify, at least during the finishing period, the breeding system of these autochthonous pigs in a “plein air” system.