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PubMed2003

Effects of processing on protein nutritive quality of coconut Cocos nucifera products.

Pared, comminuted and blanched coconut meat was freeze-dried at 25 degrees C for 24 hours and pulverized. Whole coconut meal was solvent extracted with n-hexane to yield a defatted meal while full-fat coconut protein concentrate (FFC-PC) containing 27.60% protein was prepared by alkali extraction of undefatted meal followed by isoelectric precipitation. Defatted coconut meal had a significantly (p < or = 0.05) lower crude fat but higher protein content than whole coconut meal. Similarly, FFC-PC had a significantly (p < or = 0.05) higher protein but lower carbohydrate content than whole coconut meal and defatted coconut meal. Whole coconut meal, defatted coconut meal and FFC-PC had PERs of 1.98, 2.18 and 2.48 respectively, with NPRs of 2.86, 3.28 and 3.92, respectively. Protein digestibility values of 88.75%, 89.30% and 94.02% were obtained for whole coconut meal, defatted coconut meal and full-fat coconut protein concentrate, respectively. Growth response of animals showed that FPC-PC was superior to all other test diets.

Animals↗
PubMed2002

Holmium: YAG laser rescue for a stuck stone basket.

A 35-year-old man with left lower ureteric stone underwent ureteroscopic stone removal. Holmium: YAG laser lithotripsy was used to break the stone and to remove a larger fragment a 3 Fr. steel wire stone basket was introduced through the ureteroscope. However, during removal the basket with the stone became impacted in the intramural part of the ureter. All attempts to dislodge the stone and the basket failed. Laser fiber was introduced through the second channel of the ureteroscope bridge and the laser activated at settings of 0.5J and 10Hz. Pulverization of the stone did not free the basket and hence 2 wires of the stuck basket were cut with the laser. This enabled the basket to be freed and easily removed.

Adult↗
PubMed2003

Enrichment of a microbial culture capable of reductive debromination of the flame retardant tetrabromobisphenol-A, and identification of the intermediate metabolites produced in the process.

Tetrabromobisphenol-A is a reactive flame retardant used in the production of many plastic polymers. In previous research, it was demonstrated that anaerobic microorganisms from contaminated sediment debrominate tetrabromobisphenol-A to bisphenol-A, but an enrichment culture was not established. The current study was carried out to identify the intermediate metabolites in this process and to determine the factors facilitating enrichment of debrominating microorganisms. During the enrichment process in an anaerobic semi-continuous batch reactor, tetrabromobisphenol-A debromination gradually slowed down with concurrent accumulation of three intermediate products. These compounds were tentatively identified using GC-MS as tri-, di-, and mono-brominated bisphenol-A. GC-MS and HPLC analyses showed one dominant metabolite of dibromobisphenol-A, and NMR analysis identified it as 2,2'-dibromobisphenol-A. Addition of sterile sediment (15% wt/wt) to the reactor stimulated debromination of tetrabromobisphenol-A. Furthermore, different solid amendments such as surface soil and pulverized gray chalk from the site subsurface (100 m below ground) were also stimulating agents. We conclude that organic matter is involved in stimulation since the stimulation effect of the sediment, soil and gray chalk was abolished after it was heat-treated to 550 degrees C. Our study suggests that the debrominating culture requires some organic components found in the sediment, soil, and chalk in order to sustain activity and perhaps to survive. The possible mechanisms of stimulation by these solids are discussed.

Anaerobiosis↗
PubMed2004

Steady-state and frequency-domain lifetime measurements of an activated molecular imprinted polymer imprinted to dipicolinic acid.

We recently demonstrated the synthesis and fluorescence activity associated with an optical detector incorporating a molecular imprinted polymer (MIP). Steady-state and time-resolved (lifetime) fluorescence measurements were used to characterize the binding activity associated with MIP microparticles imprinted to dipicolinic acid (DPA). DPA is a unique biomarker associated with the sporulation phase of endospore-forming bacteria. Vinylic monomers were polymerized in a dimethylformamide solution containing DPA as a template. The resulting MIP was then pulverized and sorted into small microscale particles. Tests were conducted on replicate samples of biologically active cultures representing both vegetative stationary phase and sporulation phase of Bacillus subtilis in standard media. Samplers were adapted incorporating the MIP particles within a dialyzer cartridge (500 MW). The permeability of the dialyzer membrane permitted diffusion of lighter molecular weight constituents from microbial media effluents to enter the dialyzer chamber and come in contact with the MIP. Results showed dramatic (10-fold over background) steady-state fluorescence changes (as a function of excitation, emission and intensity) for samples associated with high endospore biomass (DPA), and a frequency-domain lifetime of 5.3 ns for the MIP-DPA complex.

Bacillus subtilis↗
PubMed1983

Simultaneous micro measurement of steroid receptors in breast cancer.

The oestradiol (RE) and progesterone (RP) receptor levels were analyzed in 26 tumour fragments (200-500 mg) from breast cancer patients. After pulverization of tissue, one part was analyzed by the routine dextran-coated charcoal (DCC) method and the other by a micromethod as follows: (i) cytosol incubation using the DCC method but in the simultaneous presence of [3H]oestradiol and [3H]R5020 (ii) extraction of the steroids bound to the receptor by precipitation with ethanol/TCA (iii) high pressure liquid chromatography (HPLC) on a modular system, with a C185 microns column and an elution by gradient mixture methanol/water. The fractions were collected and the radioactivity counted. The separation of oestradiol from R 5020 was rapid and complete. In addition dexamethasone was separated by this system making possible triple measures of RE, RP and glucocorticoid receptors. A highly significant correlation was obtained between the 2 methods: RE = 0.996, P less than 0.001; RP r = 0.975, P less than 0.001, implying that the thresholds of positivity, i.e. for therapeutic decisions, remain unchanged. Simultaneous measurement of RE and RP in a single needle biopsy is possible with this micromethod.

Breast Neoplasms↗
PubMed2005

Particle size and energetics of gouge from earthquake rupture zones.

Grain size reduction and gouge formation are found to be ubiquitous in brittle faults at all scales, and most slip along mature faults is observed to have been localized within gouge zones. This fine-grain gouge is thought to control earthquake instability, and thus understanding its properties is central to an understanding of the earthquake process. Here we show that gouge from the San Andreas fault, California, with approximately 160 km slip, and the rupture zone of a recent earthquake in a South African mine with only approximately 0.4 m slip, display similar characteristics, in that ultrafine grains approach the nanometre scale, gouge surface areas approach 80 m2 g(-1), and grain size distribution is non-fractal. These observations challenge the common perception that gouge texture is fractal and that gouge surface energy is a negligible contributor to the earthquake energy budget. We propose that the observed fine-grain gouge is not related to quasi-static cumulative slip, but is instead formed by dynamic rock pulverization during the propagation of a single earthquake.

Journal Article↗
PubMed2002

Assessment of relative accuracy in the determination of organic matter concentrations in aquatic systems.

Accurate determinations of total (TOC), dissolved (DOC) and particulate (POC) organic carbon concentrations are critical for understanding the geochemical, environmental, and ecological roles of aquatic organic matter. Of particular significance for the drinking water industry, TOC measurements are the basis for compliance with US EPA regulations. The results of an interlaboratory comparison designed to identify problems associated with the determination of organic matter concentrations in drinking water supplies are presented. The study involved 31 laboratories and a variety of commercially available analytical instruments. All participating laboratories performed well on samples of potassium hydrogen phthalate (KHP), a compound commonly used as a standard in carbon analysis. However, problems associated with the oxidation of difficult to oxidize compounds, such as dodecylbenzene sulfonic acid and caffeine, were noted. Humic substances posed fewer problems for analysts. Particulate organic matter (POM) in the form of polystyrene beads, freeze-dried bacteria and pulverized leaf material were the most difficult for all analysts, with a wide range of performances reported. The POM results indicate that the methods surveyed in this study are inappropriate for the accurate determination of POC and TOC concentration. Finally, several analysts had difficulty in efficiently separating inorganic carbon from KHP solutions, thereby biasing DOC results.

Environmental Monitoring↗
PubMed2005

Adenine nucleotides in snail muscles as one of biomarkers of fluoride toxicity.

The aim of this work was to determine the extent of bioaccumulation of fluorides in tissues of Helix aspersa maxima. The toxicity of fluorides administered orally on the energy balance of the snail's foot was investigated based on measurements of concentrations of adenine nucleotides and their metabolism degradation products. Quantitation of fluoride levels was done in soft tissues (foot, hepatopancreas) and shells of mature snails. Qualitative and quantitative analysis of purine compounds was performed in slices of foot from mature snails. Fluoride concentrations in pulverized shells were measured using an ion-selective electrode. Gas chromatography was used to determine fluoride concentrations in soft tissues (hepatopancreas and foot). Purines were measured in foot muscle slices with high-performance liquid chromatography (HPLC). Fluoride levels in soft tissues of the snail cannot serve as an indicator for biomonitoring purposes as no significant accumulation was observed during exposure to maximum allowable concentrations of fluoride in drinking water. Contrary to this, levels of fluoride in the shell rose significantly with this concentration of fluoride in drinking water. The effect of fluorides on energy metabolism of foot muscle was evidenced by elevated AMP levels, increased adenine nucleotide pool and reduced conversion of ADP to ATP. Exposure to rising F(-) concentrations was accompanied by decreasing values of the adenylate energy charge AEC. Determination of AMP or AEC in foot muscle of exposed snails seems to be a useful indicator of fluoride effects on metabolic activity.

Adenine Nucleotides↗
PubMed1969

Isolation and properties of hyaluronic acid from bovine heart valves.

1. A soluble extract of bovine heart valves was obtained after the tissue had been pulverized at liquid-nitrogen temperatures in a mill. 2. Hyaluronic acid was isolated from the crude extract by sedimentation equilibrium in a caesium chloride density gradient (Franek & Dunstone, 1966). 3. Analysis of the product indicated that it contained 15% of protein and the molar ratio of glucuronic acid to glucosamine was 1.27. 4. Its physicochemical properties, as determined by lightscattering, viscosity and sedimentation studies, suggested that its molecular size and configuration were similar to those of hyaluronic acid isolated from ox synovial fluid (Preston, Davies & Ogston, 1965).

Animals↗
PubMed1969

The mass-spectrometirc identification of hypoxanthine and xanthine ('oxypurines') in skeletal musce from two patients with congenital xanthine oxidase deficiency (xanthinuria).

1. The presence of hypoxanthine and xanthine in the skeletal muscle of two patients with congenital xanthine oxidase deficiency (xanthinuria) was demonstrated by high-resolution mass spectrometry. 2. Evidence was obtained for the presence of a trace of hypoxanthine only in normal muscle. 3. Dry pulverized tissue was introduced directly into the mass spectrometer and preliminary chemical processing of the tissue was therefore unnecessary. 4. The criteria for the mass-spectrometric identification of hypoxanthine and xanthine in the tissue and the significance of the observations are discussed.

Adult↗
PubMed1998

Factors affecting solubility and penetration of clarithromycin through gastric mucus.

BACKGROUND: Factors influencing the pharmacokinetics of clarithromycin in gastric mucus are poorly defined. AIM: To determine: (i) whether the clinical formulation of clarithromycin (Biaxin granules and powdered Biaxin tablets) affects the water solvency of the antibiotic or changes the barrier properties of pig gastric mucus (PGM), thereby influencing the penetration of clarithromycin through the gastric mucus layer; and (ii) whether topically active anti-ulcer agents affect clarithromycin penetration through gastric mucus. METHODS: Solubility of clarithromycin in aqueous solution was studied at pH 7. PGM viscosities were determined using a falling ball microviscometer. Permeability of clarithromycin through PGM with and without added anti-ulcer drugs at pH 7 was monitored using a microfiltration device and an agar diffusion bioassay. RESULTS: Clarithromycin showed the poorest solubility at pH 7, whereas both Biaxin formulations demonstrated identical solubility of their antibiotic ingredient. Clarithromycin and both Biaxin formulations markedly increased mucin viscosity over the pH range 2-7. PGM markedly retarded the penetration of clarithromycin: unformulated clarithromycin and Biaxin tablets penetrated more rapidly through mucus than Biaxin granules. Pre-treatment of PGM with aluminium-magnesium-containing antacids (Riopan and Talcid preparations) decreased the rate of clarithromycin penetration, whereas Carafate and Peptobismol had no significant effect on mucus penetration of clarithromycin. CONCLUSIONS: The availability of clarithromycin in gastric mucus is significantly influenced by its clinical formulation, which affects its solubility as well as the viscous properties of mucus. Pulverized Biaxin tablets provide better local distribution of clarithromycin in mucus than Biaxin granules. Pre-treatment of mucus with anti-ulcer medications does not increase the penetration of clarithromycin through mucus.

Absorption↗
PubMed2002

Electron and light microscopy studies on the domain structures of Zn3B7O13Cl, Zn3B7O13Br and Zn3B7O13I ferroic boracites.

The domain structures of Zn3B7O13Cl, Zn3B7O13Br and Zn3B7O13I boracite single crystals were studied by means of polarized light in conjunction with electron microscopy. Single crystals of the three compositions were grown by chemical transport reactions in closed quartz ampoules, at a temperature of 900 degrees C and were examined by polarizing optical microscopy (PLM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). For both PLM and SEM, the same as-grown samples were used without having to resort to metallization of the crystal faces. For TEM the single crystals were crushed and mounted on holey carbon films. Comparative electron microscope images were useful for revealing the domain structure of these ferroelectric/ferroelastic materials previously observed between the crossed polars of an optical microscope. X-ray diffraction analysis of the pulverized crystals was performed for this triad of halogen boracites containing zinc as a common metal.

Journal Article↗
PubMed1997

A new method for assessing masticatory performance: a feasibility and reproducibility study.

The aim of this study was to develop a method for assessing masticatory performance based on incorporation of a colour binder in a test material with the presumption that the absorption of the colour is proportional to the total surface area of the masticated material. This was tested in vitro with erythrosin as the colour substance and Praestol 655BC as the colour binder incorporated into Satou's synthetic test material (equal amount of carnauba wax and bariumsulphate). The authors found that the difference in spectrophotometrical absorbance between a standard erythrosin solution and the supernatant of the same solution incubated half an hour with artificially pulverized test material was almost linearly correlated (r = 0.997) with the particle surface. This test material was then fabricated as small tablets and four adults chewed repeatedly five grams of these tablets to assess selectivity and reproducibility of the method. A good selectivity was found in that within the total range of the difference in absorbance (0.47-1.19) an inter-individual difference of more than 0.17 is significant on a 95% level with double experiments. There were no differences in the intra-individual variation for double determinations between immediate repeat and 1 week interval performances but the reproducibility was disturbed when two subjects used their partial dentures.

Absorption↗
PubMed1999

A laboratory assessment of enamel hypoplasia of teeth with varying severities of dental fluorosis.

The effect of lifelong exposure to drinking-water containing fluoride on tooth enamel microhardness was investigated. Dental fluorosis of teeth from adult subjects, who lived continuously since birth in areas characterized by the hot climate of India, supplied by drinking-water containing between 0.5 and 8.7 parts/10 F, was estimated by the Dean score. Tooth enamel sections were examined from the enamel surface towards the dentino-enamel junction (DEJ) for microhardness. Separated enamel crowns were pulverized and analysed for fluoride. Regarding the distribution of the fluoride concentrations in the drinking-water, we selected a partition below and above 0.8 parts/10 F as a criterion for comparison between the results. Tooth enamel of humans from Israel living in a drinking-water area containing about 0.5 parts/10 F was also examined. Positive associations were evident between fluoride in drinking-water, fluoride concentrations in the bulk enamel and fluorosis selection. A significantly high inverse relationship was evident between the fluoride concentration of the drinking-water and the subsurface enamel microhardness. In similar fluoride-concentration drinking-water areas of India and Israel the microhardness of the subsurface enamel was less for the Indian teeth. The microhardness of the enamel near the DEJ for the three different water fluoride-concentration areas was not significantly different.

Adult↗
PubMed2003

Occlusal phase of gum-chewing strokes.

The occlusal phase of chewing is especially interesting because food particles are being pulverized in this phase. For efficient chewing the upper and lower teeth must come together in a congruent fashion with less variation than in other phases. To examine this expectation the chewing motions of 28 women were recorded optoelectrically, and their frontal and sagittal angles of the closing and following opening strokes were measured at 3.0 mm (3-D linear distance) of opening. Closing strokes were more stable than opening strokes. The frontal angle was correlated with the sagittal angle during closing. The opening and closing sagittal angles were moderately correlated, and the opening and closing frontal angles were negatively correlated at the intersubject level. No direct association was found between the closing strokes and following opening strokes at the intra-subject level. These results suggest that closing strokes are more stable than opening strokes, resulting in efficient mastication.

Adult↗
PubMed2001

Steinstrasse after extracorporeal shockwave lithotripsy: aetiology, prevention and management.

OBJECTIVE: To determine the causes of steinstrasse, methods of prevention and treatment strategies. PATIENTS AND METHODS: Fifty-two patients with steinstrasse were identified and treated: all patients were initially treated conservatively but when there was obstruction, infection or no progression of the stone fragments, further treatment was used, ranging from repeated extracorporeal shockwave lithotripsy (ESWL), percutaneous nephrostomy (PCN), endoscopic manipulations and finally open surgery, depending on the degree of obstruction, infection, renal function and response to each kind of therapy. RESULTS: Conservative management was successful in 25 patients (48%), repeated ESWL in 12 (23%), PCN in 10 (19%), ureteroscopy in three (6%) and open surgery in two (4%). CONCLUSION: As many patients, and particularly those with larger stones, are treated by ESWL, the risk of developing steinstrasse will increase, with associated patient discomfort, infection or impaired renal function. The optimum selection of cases (aiming to pulverize the stones rather than fragment them) and accurate stone targeting are essential to minimise the development of steinstrasse. The meticulous follow-up of patients with steinstrasse should prevent any loss of renal function. When there is obstruction and/or infection or renal damage, active treatment is indicated, of which ESWL and PCN are the most effective, with ureteroscopy and open surgery reserved for difficult cases.

Adult↗
PubMedDate not supplied

Gelatinase activity in keloids and hypertrophic scars.

Keloids and hypertrophic scars are characterized by excessive deposition of collagen, which may result from insufficient protein degradation. Little is known about the levels of two gelatinases, matrix metalloproteinase-2 (72 kD type IV collagenase) and matrix metalloproteinase-9 (matrix metalloproteinase-9; 92 kD type IV collagenase) in these abnormal scars. The purpose of this study was to determine levels of these proteinases in tissue from hypertrophic scars, keloids, and donor skin. Ten hypertrophic scar samples, 9 keloid samples, and 10 donor skin samples were frozen, pulverized, homogenized, clarified by centrifugation, and analyzed for matrix metalloproteinases by quantitative zymography. Identity of matrix metalloproteinases was determined using a conditioned media reference standard, molecular weight ladders, and Western blotting. Levels of matrix metalloproteinase-9 activity were very low or undetectable in all samples. However, matrix metalloproteinase-2 activity was significantly elevated in keloids and hypertrophic scars vs. donor samples: 2.6 and 3.9-fold increases for latent matrix metalloproteinase-2, 7.8 and 6.9-fold increases for active matrix metalloproteinase-2, respectively. We conclude that little matrix metalloproteinase-9 activity (the gelatinase involved in early tissue repair) is present in keloids and hypertrophic scars, while matrix metalloproteinase-2 activity (the gelatinase involved in prolonged tissue remodeling) is present in donor skin and is significantly increased in hypertrophic scars and keloids.

Blotting, Western↗
PubMed2001

Human kallikrein gene 5 (KLK5) expression is an indicator of poor prognosis in ovarian cancer.

Kallikrein gene 5 (KLK5, also known as KLK-L2), located on chromosome 19q13.4, is one of the newly identified members of the kallikrein gene family, which is a subgroup of the serine protease enzyme family. In normal human tissues, KLK5 is highly expressed in skin, mammary gland and testis. Preliminary RT-PCR analysis has indicated that KLK5 is expressed in a subset of ovarian tumours. We have thus hypothesized that KLK5 may be a new prognostic indicator in ovarian cancer. We have examined the mRNA expression of KLK5 in 142 malignant ovarian tissues. Tumours were pulverized, total RNA was extracted, and cDNA was prepared by reverse transcription. KLK5 was amplified by PCR using gene specific primers, and the identity of the PCR product was verified by sequencing. Ovarian tissues were then classified as KLK5 positive or negative, based on ethidium bromide staining of the PCR product on agarose gels. KLK5 was found to be highly expressed in 58/142 (41%) of ovarian cancer samples while its level of expression was very low in normal ovarian tissues. We found a strong positive relation between KLK5 expression and tumour grade (P = 0.006) and disease stage (P = 0.027). Univariate survival analysis revealed that patients with ovarian tumours positive for KLK5 expression had an increased risk for relapse and death (P = 0.018 and 0.022, respectively). In multivariate analysis, KLK5 expression showed independent prognostic value only in the subset of tumours with lower grade disease (grades I and II). We conclude that KLK5 expression is associated with more aggressive forms of epithelial ovarian carcinoma and has indepdent prognostic value in low grade tumours.

Adult↗