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PubMed1995

[Disinfection of wood in mushroom growing cellars with Mycetox].

Since the use od phenolic disinfectants for impregnating and disinfecting of wood in mushroom--growing cellars was banned in Poland for ecologic and hygienic reasons, the new product, namely Mycetox, containing quaternary ammonium compound and boric acid has been registered for this purpose. Mycetox belongs to new generation products and is non toxic for man and the environment. It is first Polish product developed for the general disinfection as well as for impregnating purposes in mushroom farms. The efficacy of Mycetox in mushroom-growing cellars has been evaluated basing on its fungicidal properties in the different substrates used for the cultivation of mushrooms. Also its influence on mushroom spawn growth, crop yield, and the penetration of spawn into wooden cages impregnated with Mycetox as well as its influence on blanching of mushrooms has been investigated.

Agaricus↗

PubMed1988

Free-flow electrophoretic apparatus for separation and concentration of proteins.

Protein separation in the free-flow electrophoretic apparatus with 48 channels at both the inlet and outlet using "artificial" pH gradients was investigated. The separation was carried out in borate-mannitol pH gradients and in pH gradients created by the concentration gradient of boric acid in the solutions of borax and mannitol. The separation pattern depended on the ratio of the rate of sample injection to the flow-rate of solutions in the separation chamber and did not change when the protein concentration in the sample was changed. The protein separation in the pH gradient was better than in case of conventional free-flow electrophoresis. The free-flow electrophoretic apparatus with multi-channel inlet of the separation chamber is suitable for concentration of biological materials, e.g. proteins and bacterial cells.

Alkaline Phosphatase↗

PubMed1997

Mutagenic effects at HPRT locus induced in Chinese hamster ovary cells by thermal neutrons with or without boron compound.

CHO cells were exposed to thermal neutrons and their mutation frequency was determined. The Kyoto University Research Reactor (KUR), which has a very low level of contamination by gamma-rays and fast neutrons was used as a thermal neutron source. Cells were irradiated in the presence or absence of boric acid to determine mutation frequency and cell survival. Thermal neutron irradiation was 2.5 times as mutagenic as gamma-irradiation without boron. In the presence of boron, however, thermal neutron irradiation was from 4.2 to 4.5 times as mutagenic as gamma-irradiation. When the mutation frequency was plotted against the survival fraction, a higher degree of mutagenicity was observed in the presence than in the absence of boron. These results suggest that the enhancement of thermal neutron-induced mutation with boron is strongly associated with alpha-particles released by 10B(n, alpha)7 Li reaction.

Animals↗

PubMed2004

[Study on the fingerprints of Belamcanda chinensis (L.) DC by capillary electrophoresis].

A capillary electrophoresis fingerprints (CEFP) method was established to evaluate the quality of Belamcanda chinensis (L.) DC. The background electrolyte (BGE) was a 80 mmol/L boric acid containing 15 mmol/L borate solution (adjusted pH 9.7 with KOH solution). The detection wavelength was 228 nm and 12.1 kV was applied. The Belamcanda chinensis (L.) DC was extracted by water to obtain a CEFP containing 21 peaks. The CEFP has good precision, reproducibility and stability with the relative standard deviations (RSDs) of the relative migration time less than 3.5% and the RSDs of the relative peak area about 5.0%. There were good similarities between the standard CEFP and each CEFP of samples collected from ten different places. The coefficients were from 0.913 to 0.993. Meanwhile, fundamental studies related to the methods in peak identification of fingerprints and content evaluation of different sample constituents were carried out.

Boric Acids↗

PubMed1977

Laboratory assessment of physical and chemical methods of preserving urine specimens.

Three methods of preserving simulated specimens of urine were studied with six test strains of bacteria. Viable counts were measured by a surface viable count and by the filter-paper-strip method during a holding period of 72 hours. Refrigeration at approximately 4 degrees C was effective and reliable. Boric acid (1-8%) at room temperature was toxic for the strain of Escherichia coli at a density of 10(7) cfu/ml but this may not be significant at the higher concentration of bacterial cells often found in clinical specimens. NaCl-polyvinylpyrrolidone (PVP) solutions containing PVP of mol. wt 44 000 or 700 000 were not effective; they were toxic for the Gram-negative strains and did not retard the growth of Micrococcus subgroup 3. The two methods of measuring viable counts were compared for specimens held under different conditions; the specificity of the filter-paper-strip method was high but the sensitivity was low when many of the specimens contained approximately 10(5) cfu/ml.

Bacteria↗

PubMed1991

Collection and storage of capillary blood in glass fibre filters for glycated haemoglobin measurement by a microcolorimetric method.

A filter method for collection and storage of capillary blood spots for glycated haemoglobin (gHb) has been developed. Glass fibre filters (GFB) impregnated with 0.8 M boric acid were used to collect and store capillary blood. Haemoglobin from the dried blood spots was eluted into water and determined by Drabkin's method, while gHb in the eluates was determined by the microcolorimetric method. The intraassay coefficients of variation (CVs) were 4.5, 4.5 and 3.1% at 882, 1101 and 1704 pmol HMF/mg Hb, respectively. The corresponding inter-assay CVs were 8.6, 8.6 and 6.3%, respectively. A total of 63 paired capillary and venous blood samples were measured by both the direct and GFB method. The GFB method showed excellent correlation with the direct method (r = 0.948 and r = 0.994) after 7 and 14 days' storage at room temperature. The GFB method will enable prior collection and postage of blood samples by patients.

Blood Specimen Collection↗

PubMed2005

Precipitation recovery of boron from wastewater by hydrothermal mineralization.

It is well known that boric acid exhibits various toxic effects on plant, animal and human beings even at very low concentrations. Thus, the development of boron-removal technique from wastewater has been intensively investigated. In this study, a new hydrothermal treatment technique was developed to recover boron as recyclable precipitate Ca(2)B(2)O(5).H(2)O from aqueous solutions. As a result, it was found that the hydrothermal treatment using calcium hydroxide as a mineralizer converted boron in the aqueous media effectively into calcium borate, Ca(2)B(2)O(5).H(2)O. In the optimal hydrothermal condition, more than 99% of boron was collected from the synthetic wastewater of 500 ppm. Thus, the present hydrothermal treatment in the presence of calcium hydroxide is recommended as one of the effective techniques to recover boron from aqueous media.

Borates↗

PubMed1986

Thermal behavior of the gypsum binder in dental casting investments.

This study examined the thermal behavior of cast gypsum specimens, with and without additives, by means of simultaneous differential thermal analysis-thermogravimetry (DTA-TG) and dilatometry. Specimens were prepared from wet-calcined hemihydrates (Hydrocal and Densite). The additives studied were boric acid (H3BO3) and sodium chloride (NaCl), and these were added to the hemihydrate powders in concentrations of 2 wt% (in the case of H3BO3) and 0.5 wt% (in the case of NaCl). A large shrinkage was observed in the range of 300 to 500 degrees C, and this was greatly reduced when either H3BO3 or NaCl was present. The dehydration of gypsum (calcium sulfate dihydrate) was not completed until the initial stage of this large shrinkage was reached, but the phase transition of calcium sulfate anhydrite (III-CaSO4 to II-CaSO4) was the major cause for the large shrinkage. This phase transition occurred over a much wider temperature range than that suggested by the DTA-TG results. Dehydration conditions similar to those employed in wet calcination of gypsum appeared to be produced under atmospheric pressure when NaCl was present.

Boric Acids↗

PubMed2003

Rapid separation and laser-induced fluorescence detection of mutated DNA by capillary electrophoresis in a self-coating, low-viscosity polymer matrix.

The detection of point and other simple mutations in DNA is important for cancer research and diagnosis and other biological studies. Capillary electrophoresis has been successfully used for separating DNA fragments. However, a low-viscosity polymer sieving buffer for DNA separation with on-line coating has never been reported. In this paper, a new method using capillary electrophoresis with on-line coating and laser-induced fluorescence detection (CE-LIF) for screening for point or simple DNA mutations has been demonstrated. The method uses an on-line dynamic coating technique that increases capillary lifetime and analysis reproducibility, and employs a low-viscosity polymer solution, which allows the user to rinse the capillary rapidly and refill with polymer solution easily. Experiments proved that the additives in the separation buffer for on-line capillary coating do not affect the separation efficiency of the running buffer, and do not interfere with the formation of hydrogen-bonded network between boric acid, mannitol and hydroxypropylmethylcellulose polymers. The stability of the dynamically coated capillary was quantitatively studied; the capillary lifetime was increased 6- to 7-fold compared with that of permanently coated CE columns. Standard DNA fragments containing mutations, with sizes of 209, 219, and 338 bps, were successfully separated and detected with this system, after the mutated DNA fragments were cleaved by CEL-I endonuclease. The technique is very sensitive for the size-separation of low-range, middle-range, and high-range DNA fragments. Results were compared with the HPLC methods developed by Transgenomic, Inc. and were in good agreement. The method should be applicable to mutation detection for all relevant biological and clinical studies. The factors influencing separations and the stability of dynamic capillary coatings are also discussed in the paper.

Boric Acids↗

PubMed1981

Intermittent trachoma chemotherapy: a controlled trial of topical tetracycline or erythromycin.

In communities with endemic blinding trachoma, mass (or "blanket") treatment with a topically applied tetracycline derivative is a standard control measure. The widely used "intermittent" treatment schedule consists of the twice daily application of antibiotic ointment for five consecutive days once a month for six months. In this study, the efficacy of "intermittent" treatment was evaluated for the treatment of severe and moderate intensity trachoma in children in southern Tunisia. Tetracycline or erythromycin ointments (specific antichlamydial drugs) were compared with 5% boric acid ointment (a simple antiseptic) given by the intermittent schedule during the winter and spring. There was a statistically significant degree of improvement at only one examination, four weeks after the full course of treatment had been completed. When re-examined five months later there were no differences in intensity in the three groups. The limited effect of topical chemotherapy might be attributable to several causes, among which could be inadequate drug levels, inadequate treatment periods, reinfection from non-treated children in the community, and auto-infection from extraocular sites (e.g., respiratory tract) in the same child. The possible value of short-term (two weeks) systemic antimicrobial therapy as an additional strategy to prevent blindness of children with potentially blinding active trachoma is discussed.

Boric Acids↗

PubMed2002

Effect of endocrine disrupting chemicals on germinal vesicle breakdown in Xenopus in vitro.

Currently, no standardized and well-validated alternative models exist for screening for progesterone-responsive endocrine disrupting chemicals (EDCs). Because of this, a rapid assay for evaluating progestin/antiprogestin activity using Xenopus oocyte germinal vesicle breakdown (GVBD) as a model was evaluated. Five compounds, including progesterone (P), ethinyl estradiol (EE), ethylene glycol monomethyl ether (EGME), cadmium (Cd), and boric acid (B) were used to validate the model on a preliminary basis. Each test material was tested for progestin/anti-progestin activity. The binding affinity of each test material to the oocyte plasma membrane receptor (OPMR) relative to progesterone was then determined. Results from the present studies suggested that both EE and EGME were capable of inhibiting GVBD in a concentration-dependent manner. Cd had a subtle inhibitory effect at high concentrations. B had no effect on GVBD even at concentrations of 100 mg B/L, and thus appears to have no EDC activity in this model. The binding capacity of the test substances to the OMPR relative to progesterone was low. Thus, the relative inhibitory potential of the test materials study was EE > EGME >> Cd > B. However, the relative binding affinity of the toxicants to the OMPR can be expressed as P >> EGME > EE > Cd > B. Although EE was more effective in inhibiting GVBD, EGME appeared to bind more tightly to the OMPR.

Animals↗

PubMed2000

Comparisons of toxic baits for controlling the cockroach, Blattella germanica: attractiveness and feeding stimulation.

Female German cockroaches, Blattella germanica (L.) (Dictyoptera: Blattellidae) and nymphs (stages 1, 3 and 6) were used to test the attractiveness and the feeding stimulation of several commercial gel formulations of insecticide food baits in laboratory binary choice tests. The four toxic gel baits tested were: 'Avert' (0.05% abamectin=avermectin B1), 'Drax' (33.3% boric acid), 'Goliath' (0.05% fipronil) and 'Maxforce' (2.15% hydramethylnon). The attractiveness of a bait was estimated by the number of cockroaches that chose it first, and by their tendency to change to it secondarily. Feeding stimulation was estimated by the mean duration of feeding bouts and total duration of food intake. Variability of these factors was assessed in relation to age of cockroaches and to age of baits. With a few exceptions, cockroach age did not affect performance in any of these tests. Attractiveness to B. germanica ranked 'Goliath' gel higher than 'Avert', 'Drax' and 'Maxforce' gels, whether or not the active ingredient fipronil was present in 'Goliath' gel. Feeding stimulation ranked 'Avert' and 'Maxforce' gels higher than 'Goliath' gel, and 'Drax' gel was inferior. With ageing up to 3 months, the feeding stimulation power of 'Goliath' and 'Maxforce' gels increased, whereas that of 'Avert' fluctuated. Assuming that all types of bait effectively kill cockroaches once ingested, these results illustrate the importance of behavioural observations on bait efficiency and show that ranking of these different food baits varies in relation to the parameter analysed.

Age Factors↗

PubMed2000

Bacteriology of chronic otitis media in Dar es Salaam, Tanzania.

OBJECTIVES: To determine the aetiology of chronic otitis media (COM) in Dar es Salaam and to find out the shelf life of boric acid in spirit ear drops (BAISED). DESIGN: Cross-sectional study. SETTING: Muhimbili Medical Centre and selected primary schools within Dar es Salaam. MAIN OUTCOME MEASURES: Bacterial isolates and their sensitivity patterns and shelf life of BAISED. SUBJECTS AND METHODS: One hundred and seventy six pus swab specimens obtained from 150 patients with COM for more than three months were submitted for culture and antimicrobial sensitivity testing in 1997. RESULTS: The isolates included Pseudomonas aeruginosa (51.7%), Staphylococcus aureus (17.2%), Proteus mirabilis (13.2%), Klebsiella spp. (8.0%), Escherichia coli (5.8%) and unidentified coliforms in 4.0%. All isolates were sensitive to gentamicin. Sensitivity of Pseudomonas aeruginosa and Proteus mirabilis to kanamycin was 98.5% and 100%, respectively. P. aeruginosa was sensitive to chloramphenicol, ampicillin and tetracycline by 58.1%, 10.1% and 8.3%, respectively. Three per cent BAISED inhibited the growth of all Pseudomonas aeruginosa even after it has been stored at room temperature for six weeks. CONCLUSION: Based on these results, the drug of choice for management of COM in Dar es Salaam is gentamicin. However, given its ototoxicity effects and the fact that BAISED is effective and affordable, the later should be the treatment of choice.

Adolescent↗

PubMed2005

Educational intervention to control cockroach allergen exposure in the homes of hispanic children in Los Angeles: results of the La Casa study.

BACKGROUND: Cockroach allergy is common among inner city children with asthma, and exposure to cockroach allergen is associated with more severe disease. However, there has been little evaluation of educational approaches for controlling cockroach infestations and reducing allergen exposure. OBJECTIVE: An educational intervention to reduce cockroach allergen exposure in the homes of Hispanic children in Los Angeles was implemented and evaluated. METHODS: Caretakers of 150 children with asthma were randomly assigned to an in-home intervention or comparison group. In the intervention group, peer health educators trained the caretaker to control cockroaches by reducing harbourage and access to food and by applying boric acid, and to reduce allergen exposure by cleaning. Allergen impermeable covers were placed on the child's mattress and pillows. Knowledge, reported and observed behaviour, cockroach counts, and cockroach allergen (Bla g 1) in dust samples from the kitchen and the child's bedding were assessed at study entry and at follow-up 4 months later. RESULTS: There was improvement in knowledge and in observed and reported behaviour hypothesized to be associated with cockroach control. The geometric mean cockroach number in the intervention homes at the follow-up visit was 60% lower than in the non-intervention homes (95% confidence interval (CI) 14%, 81%). Geometric mean total cockroach allergen collected from the child's bedding was 64% lower in the intervention group (95% CI 12%, 85%). In homes with heavier initial cockroach infestation, there was a larger reduction in total kitchen dust allergen and concentration associated with the intervention than in homes with fewer initial cockroaches. CONCLUSIONS: We conclude that reduction in number of cockroaches and in total allergen in bedding dust can be achieved by caretakers of asthmatic children following a single home educational intervention by peer educators.

Adolescent↗

PubMed1998

Sources of human exposure: overview of water supplies as sources of boron.

Boron (B) is widely distributed in surface and groundwaters predominantly as undissociated boric acid, and is found in ocean waters at a mean level of approx 4.6 mg B/L. A recent analysis of US surface waters indicated that the 10th, 50th, and 90th percentile B levels were 0.010, 0.076, and 0.387 mg B/L, respectively. The same study found that the 50th and 90th percentile B levels in California drinking waters were 0.10 and 0.40 mg B/L, respectively. The overall mean B concentration in Canadian surface waters in 1988 was reported to be 0.16 mg B/L, with a few stations reporting concentrations above 2.0 mg B/L. Unusually high levels of B have been measured in human water supplies of northern Chile, with concentrations ranging from 0.31 to 15.2 mg B/L. River water sources of B in the UK and Northern Italy were found to range from 0.002 to 0.87 mg B/L, respectively, whereas German drinking waters had median and maximum B levels of 0.02 and 0.18 mg B/L, respectively. Bottled mineral water also represents a source of B exposure based on the largest reported survey of US and European products, with a mean level of 0.75 mg B/L and a range from <0.005 to 4.35 mg B/L. Thus, B intake from drinking water is highly variable and dependent on the geographic source, the quantities of water consumed and the water sources used to bottle other beverages.

Borates↗

PubMed2001

A new strategy for optimizing sensitivity, speed, and resolution in capillary electrophoretic separation of DNA.

DNA separations were performed in poly(ethylene oxide) (PEO) solutions prepared in 100 mM Tris-boric acid (TB) buffers using a capillary filled with TB buffers with concentrations up to 2.5 M, pH 10.0. The electroosmotic flow (EOF) increased with increasing the concentration of TB buffers till 1.5 M as a result of decreasing PEO adsorption on the capillary wall. At high TB concentrations (> 1.5 M), the peaks corresponding to small DNA fragments (11 and 8 base pairs) became sharper and were detected. Relative standard deviations of the EOF coefficient and the migration times of the DNA fragments were all less than 1% using a capillary filled with TB buffers at concentrations higher than 1.5 M. When separations were performed at different pH values of PEO solutions and TB buffers, better results in terms of sensitivity, speed, and resolution were generally achieved. The fluorescence intensity of the 2176 bp fragment obtained at pH values of TB buffers/PEO solutions 10.0/8.2 was 27-fold of that at pH values 8.2/8.2. The enhancement was related to effects of pH and borate on fluorescence intensity, DNA conformation, stacking, and interactions with the capillary wall. Using a capillary filled with 400 mM TB buffers, pH 10.0, the separation of DNA (pBR 322/HaeIII digest, pBR 328/Bg/I digest and pBR 328/HinfI digest) in 1.5% PEO solutions prepared in 100 mM TB buffers, pH 9.0, at 375 V/cm was accomplished in less than 18 min.

Boric Acids↗

PubMedDate not supplied

Evaluation of a 14-day static renewal toxicity test with Daphnia magna straus.

Two replicate 14-day static renewal chronic toxicity tests were conducted with Daphnia magna Straus for each of three test chemicals (boric acid, aniline, and 2,4-dichlorophenol). These tests were conducted at 24 +/- 2 degrees C. The objective of this study was the comparison of the 14-day test results with chronic values derived for the same chemicals from 21-day studies (20 degrees C). It was hypothesized that the comparison of the chronic data resulting from the two test regimes would support the shortening of the standard 21-day exposure period and reduce the cost of these labor intensive studies. The results of this study are as follows: 1. The 14-day test met the 21-day chronic test acceptability criteria in terms of control data associated with the mean number of broods/adult, mean total young/adult, mean brood size and survival. 2. A comparison of the results shows the similarity of the chronic values generated from the 14 and 21-day tests. In all cases, the chemical specific chronic values were within a factor of 2. The chronic values for 2,4-dichlorophenol generated from the two test regimens were virtually identical (i.e., 14-day--1.1 and 1.2 mg/L; 21-day--1.1 mg/L). 3. The comparison of the chronic values resulting from the 14 and 21-day tests supports the use of the 14-day exposure period. A shorter exposure period will help reduce the cost of these labor intensive studies without compromising their scientific integrity.

Aniline Compounds↗

PubMed2005

Sequential design of a novel PVA-based crosslinked ethylenic homopolymer for extended drug delivery.

A Box-Behnken Design was employed to study the influence of boric acid, sodium sulfate, ammonia and n-propanol in the formulation of crosslinked ethylenic homopolymeric (CEH) gelispheres from native polyvinyl alcohol (PVA). The dependent variables studied included the size of the spherical gelispheres, drug encapsulation efficiency, in vitro dissolution after 30 min and textural parameters, namely fracture force and matrix rupture energy. Based on these responses, an optimized CEH gelisphere matrix was formulated and thereafter incorporated as a powder into a candidate crosslinked zinc-pectinate multiple-unit device to assess its effect on modifying drug release. In the case of the CEH-loaded zinc-pectinate gelispheres, it was determined via constrained optimization that a maximum drug encapsulation efficiency of 28.63% could be obtained under the conditions of 0% (w/v) CEH, 13 h of crosslinking and drying temperature of 60 degrees C. On the other hand, initial drug release could be significantly retarded when 0.10% (w/v) of CEH was included in the formulation and crosslinked for 24 h at 40 degrees C. In this regard, CEH induced a 4 h lag phase. Furthermore, zero-order drug release was produced and could be maintained over several weeks. Kinetic analysis of drug release further supported that CEH inhibits polymer relaxation (k2<<k1), and hence slows down drug diffusion. Based on these results, the CEH-zinc-pectinate drug delivery system appears to be a suitable carrier that may be employed for long-term administration for, e.g. via subcutaneous implantation.

1-Propanol↗