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PubMed1999

Effect of crystallinity of microcrystalline cellulose on the compactability and dissolution of tablets.

Microcrystalline cellulose (MCC) was pulverized with a vibrational rod mill. The degree of crystallinity of MCC decreased from 65.5 to 12.1% with pulverization time due to mechanochemical effect. Pulverized MCCs were compressed at 155.6 MPa using a compression test apparatus, and the two parameters relating to compactability, the B value and yield pressure, were calculated using a Heckel plot. These values were lowered as the degree of crystallinity of MCC became smaller. These results suggest that the crystal region and the amorphous region in MCC particles may be mainly fractured and deformed plastically during compression, respectively. Then the dissolution test was performed for the acetaminophen-MCC (10:90) tablets. Dissolution profiles showed an interesting phenomenon, namely, the dissolution rate of acetaminophen from MCC tablet decreased when the degree of crystallinity of MCC was in the range from 65.5 to 37.6%, however, it increased markedly when the degree of crystallinity of MCC was in the range from 25.8 to 12.1%. The amount of water absorbed into tablets changed in accord with the dissolution rates of acetaminophen from tablets. The dissolution data indicate that drug release can be modified by changing the degree of crystallinity of MCC.

Cellulose↗
PubMed2001

Further biogeochemical characterization of a trichloroethene-contaminated fractured dolomite aquifer: electron source and microbial communities involved in reductive dechlorination.

A recent article presented geochemical and microbial evidence establishing metabolic adaptation to and in-situ reductive dechlorination of trichloroethene (TCE) in a fractured dolomite aquifer. This study was designed to further explore site conditions and microbial populations and to explain previously reported enhancement of reductive dechlorination by the addition of pulverized dolomite to laboratory microcosms. A survey of groundwater geochemical parameters (chlorinated ethenes, ethene, H2, CH4, DIC, DOC, and delta13C values for CH4, DIC, and DOC) indicated that in situ reductive dechlorination was ongoing and that an unidentified pool of organic carbon was contributing, likely via microbial respiration, to the large and relatively light on-site DIC pool. Petroleum hydrocarbons associated with the dolomite rock were analyzed by GC/MS and featured a characteristically low delta13C value. Straight chain hydrocarbons were extracted from the dolomite previously found to stimulate reductive dechlorination; these were particularly depleted in hexadecane (HD). Thus, we hypothesized that HD and related hydrocarbons might be anaerobically respired and serve both as the source of on-site DIC and support reductive dechlorination of TCE. Microcosms amended with pulverized dolomite demonstrated reductive dechlorination, whereas a combusted dolomite amendment did not. HD-amended microcosms were also inactive. Therefore, the stimulatory factor in the pulverized dolomite was heat labile, but that component was not HD. Amplified Ribosomal DNA Restriction Analysis (ARDRA) of the microbial populations in well waters indicated that a relatively low diversity, sulfur-transforming community outside the plume was shifted toward a high diversity community including Dehalococcoides ethenogenes-type microorganisms inside the zone of contamination. These observations illustrate biogeochemical intricacies of in situ reductive dechlorination reactions.

Bacteria, Anaerobic↗
PubMed1983

Development of the swallowable composition of food in normal dentate subjects.

This study aimed to find out the changes which occur in the frequency distribution of the size of particles produced during mastication of a convenient mouthful of hard-baked soya beans to its swallowable composition (SC), and to identify the particles which undergo rapid pulverization. In this group the total number of masticatory strokes utilized to prepare food for the SC varied between forty and eighty masticatory strokes. All the subjects produced a similar pattern of the frequency distribution of particles produced at the end of mastication and when mastication was interrupted at a particular phase. Particles larger than 1180 micrometers were pulverized to form particles smaller than 1180 micrometers. Most rapid pulverization was seen in particles of 2400 micrometers whereas particles of average size 655 micrometers, formed rapidly.

Adult↗
PubMed2006

Water ingestion by rats fed a high-salt diet may be mediated, in part, by visceral osmoreceptors.

After surgical removal of all salivary secretions ("desalivation"), rats increase their consumption of water while eating dry laboratory chow. In the present experiments, desalivated rats drank even more water while they ate "powdered" high-salt food (i.e., <15-mg food particles). The Na+ concentration of systemic plasma in these animals was not elevated during or immediately after the meal, which suggests that cerebral osmoreceptors were not involved in mediating the increased water intake. A presystemic osmoregulatory signal likely stimulated thirst because the Na+ and water contents of the gastric chyme computed to a solution approximately 150 mM NaCl. In contrast, desalivated rats drank much smaller volumes of water while eating "pulverized" high-salt food (i.e., 60-140-mg food particles), and the fluid mixture in the gastric chyme computed to approximately 280 mM NaCl solution. These and other findings suggest that the NaCl ingested in the powdered high-salt diet was dissolved in the gastric fluid and that duodenal osmoreceptors (or Na+-receptors) detected when the concentration of fluid leaving the stomach was elevated after each feeding bout, and promptly stimulated thirst, whereupon rats drank water until the gastric fluid was diluted back to isotonicity. However, when rats ate the pulverized high-salt diet, much of the NaCl ingested may have been embedded in the gastric chyme and therefore was not accessible to visceral osmoreceptors once it emptied from the stomach. Consistent with that hypothesis, fluid intakes were increased considerably when desalivated rats drank 0.10 M NaCl instead of water while eating either powdered or pulverized high-salt food.

Animals↗
PubMed2005

A new immunomodulatory function of low-viscous konjac glucomannan with a small particle size: its oral intake suppresses spontaneously occurring dermatitis in NC/Nga mice.

BACKGROUND: Konjac glucomannan (GM) is a well-known dietary fiber with various beneficial functions: the higher viscosity displayed the stronger potency. However, the high-viscous GM powders, ordinary konjac powder and highly purified GM were mostly unsuitable for the application to various food industries. Our aims are to develop new physiological functions of low-viscous GM powder, pulverized GM or re-granulated fine GM, using a murine model of atopic dermatitis. METHODS: Male 4-week-old NC/Nga mice were fed for 8 weeks on diets containing 5% of two high-viscous and two low-viscous GM powders, respectively. RESULTS: Striking suppression against the aggravation of dermatitis, the increase in scratching behaviors, and the rise in IgE levels was recognized only in mice fed on the pulverized GM diet, but not in mice fed on the other GM diets or a control diet. Eczema prevention in the fine GM-fed mice was accompanied by a significant decrease in their plasma IFN-gamma levels, a positive regulatory cytokine for atopic skin inflammation. CONCLUSION: Only the pulverized GM possessed the ability to suppress the development of dermatitis in NC/Nga mice. This is the new immunomodulatory function of low-viscous GM with a small particle size.

Administration, Oral↗
PubMed1998

Soil is an important pathway of human lead exposure.

This review shows the equal or greater importance of leaded gasoline-contaminated dust compared to lead-based paint to the child lead problem, and that soil lead, resulting from leaded gasoline and pulverized lead-based paint, is at least or more important than lead-based paint (intact and not pulverized) as a pathway of human lead exposure. Because lead-based paint is a high-dose source, the biologically relevant dosage is similar to lead in soil. Both lead-based paint and soil lead are associated with severe lead poisoning. Leaded gasoline and lead in food, but not lead-based paint, are strongly associated with population blood lead levels in both young children and adults. Soil lead and house dust, but not lead-based paint, are associated with population blood lead levels in children. Most soil lead and house dust are associated with leaded gasoline. Lead-based paint dust is associated with cases of renovation of either exterior or interior environments in which the paint was pulverized. Based upon the limited data to date, abatement of soil lead is more effective than abatement of lead-based paint in reducing blood lead levels of young children. About equal numbers of children under 7 years of age are exposed to soil lead and lead-based paint. Seasonality studies point to soil lead as the main source of population blood lead levels. Soil lead is a greater risk factor than lead-based paint to children engaged in hand-to-mouth and pica behavior. In summary, soil lead is important for addressing the population of children at risk of lead poisoning. When soil lead is acknowledged by regulators and the public health community as an important pathway of human lead exposure, then more effective opportunities for improving primary lead prevention can become a reality.

Child↗
PubMed1998

Comparison of six extraction techniques for isolation of DNA from filamentous fungi.

Filamentous fungi have a sturdy cell wall which is resistant to the usual DNA extraction procedures. We determined the DNA extraction procedure with the greatest yield of high quality fungal DNA and the least predilection for cross-contamination of equipment between specimens. Each of six extraction methods was performed using Aspergillus fumigatus hyphae. The six methods were: (1) glass bead pulverization with vortexing; (2) grinding with mortar and pestle followed by glass bead pulverization; (3) glass bead pulverization using 1% hydroxyacetyl trimethyl ammonium bromide (CTAB) buffer in a water bath sonicator; (4) water bath sonication in CTAB buffer; (5) grinding followed by incubation with CTAB; and (6) lyticase enzymatic cell lysis. Genomic DNA yields were measured by spectrophotometry and by visual reading of 2% agarose gels, with shearing assessed by the migration of the DNA on the gel. Genomic fungal DNA yields were highest for Method 1, followed by Methods 5 approximately = to 2 >3 approximately = to 4 approximately = to 6. Methods 2 and 5, both of which involved grinding with mortar and pestle, led to shearing of the genomic DNA in one of two trials each. We conclude that the use of glass beads with extended vortexing is optimal for extraction of microgramme amounts of DNA from filamentous fungal cultures.

Aspergillus fumigatus↗
PubMedDate not supplied

[Method of production of the dried highly dispersed vaccine of Newcastle disease virus].

Experimental batches of dried dust-like vaccine on the basis of Newcastle disease virus, strain La Sota, have been prepared. The technology of the preparation of the vaccine includes the lyophilization of the technical fluid of the culture under study, milling dried biomass and mixing the pulverized biomass with excipient. As revealed in the process of this work, lyophilization ensures high concentration of the virus in dried biomass and its pulverization, a high content of the target fraction of biomass particles in the vaccine preparation with the moderate inactivation of the bioagent. By mixing the pulverized biomass with excipient the required concentration of the viable virus in the finished product may be achieved. The viability of the bioagent during the storage of the dried vaccine under conditions, determined by optimum storage temperature and time, has been found satisfactory.

Aerosols↗
PubMed2003

[Distribution of fluoride in the combustion products of coal].

The static distribution characteristic of fluoride in the combustion products of coal was studied by ashing procedure of coal, and the dynamic distribution characteristics of fluorine in the combustion products of coal in pulverized-coal-fired boiler and layer-burning boiler were investigated. Experimental results identified that fluorine in coal belong to volatile elements, fluorine in fly ash and bottom ash were non-rich. About 94.5% of the fluorine in coal emitted as gaseous-fluorine during coal combustion in pulverized-coal-fired boiler, and about 80% of the fluorine in coal emitted as gaseous-fluorine during coal combustion in layer-burning boiler. 55%-60% of the fluorine in fly ash of pulverized-coal-fired boiler were distributed in fly ash particles with a diameter of 74 microns-104 microns.

Carbon↗
PubMed2006

[Solubilities of ephedrine and d-pseudo-ephedrine from different sizes of ultramicro-particles of the compound traditional Chinese herbs Maxing Shigan decoction].

OBJECTIVE: To compare the solubilities of ephedrine and d-pseudo-ephdrine in the compound of traditional Chinese drugs--Maxing Shigan decoction with and without ultramicro-pulverizations using a RP-HPLC procedure. METHOD: The analytical column was a YMC ODS-C18(4.6 mm x 150 mm,4 microm). A mixture of water-acetonitrile-sodium dodecyl sulfate-phosphorous acid (650:350:5:1) was used as the mobile phase at flow rate of 1.5 mL x min(-1). The column temperature was 50 degrees C and the wavelength was 210 nm. RESULT: In this way, ephedrine and d-pseudo-ephedrine of the compound samples can be separated well and showed significant differences before and after the ultramicro-pulverizations. CONCLUSION: For the Maxing Shigan decoction, the dissolution rates and solubilites of ephedrine and d-pseudo-ephedrine ultramicro-pulverization were greatly improved.

Calcium Sulfate↗
PubMed1994

Comparative study of chewable pyrantel pamoate: should standards for chewable tablets be revised?

Chewable pyrantel pamoate tablets were administered to children randomly assigned to three treatment groups. Individuals in each group were instructed either to swallow whole, to chew and swallow, or to swallow previously pulverized tablets. With respect to Ascaris, results of posttreatment stool examinations indicated no differences in cure rates and egg reduction rates between the different modes of treatment. However, for both hookworm and Trichuris, mean egg counts increased for both swallow and chew groups, but decreased in the pulverized group. In addition to the highest egg reduction rates, the most parasitological cures were also seen in the pulverized group for these two worms. The status of standards for chewable tablets is discussed. Until the standards are changed it is recommended that all chewable tablets be crushed before swallowing.

Adolescent↗
PubMedDate not supplied

[Comparative analysis of lithiasic fragmentation induced by extracorporeal and direct contact sources].

An in vitro experimental study on stone fragmentation was conducted on 114 calculi analyzed by infrared spectrophotometry. Four energy sources were utilized: electrohydraulic, piezoelectric, ultrasound and pulsed laser. We analyzed stone susceptibility to fragmentation (particles < 3 mm), pulverization (particles < 1 mm) and stone fragility (amount of energy/mg of calculus fragmented into particles < 3 mm) for each type of energy source of each of the following 6 stone compositions: calcium oxalate monohydrate, calcium oxalate dihydrate, magnesium ammonium phosphate, phosphate carbonate, uric acid and phosphate oxalate. The calcium oxalate dihydrate calculi were the most susceptible to fragmentation and the infective calculi (magnesium ammonium phosphate and phosphate carbonate) were the most susceptible to pulverization. The piezoelectric energy showed the highest capacity for fragmentation and pulverization of calculi. Stone fragility depended on each stone type and the energy source utilized.

Humans↗
PubMed1995

Linkage analysis of chromosome 22q12-13 in a United Kingdom/Icelandic sample of 23 multiplex schizophrenia families.

A possible linkage to a genetic subtype of schizophrenia and related disorders has been reported on the long arm of chromosome 22 at q12-13. (Pulver et al., 1994: Am J Med Genet 54:36-43; Coon et al., 1994: Am J Med Genet 54:72-79; Pulver et al., 1994: Am J Med Genet 54:44-50). However formal statistical tests in a combined sample could not reject homogeneity and prove that there was a linked subgroup of families. We have studied 23 schizophrenia pedigrees to test whether some multiplex schizophrenia families may be linked to the microsatellite markers D22S274 and D22S283 which span the 22q12-13 region. Two point followed by multipoint lod and non-parametric linkage analyses under the assumption of heterogeneity provided no evidence for linkage over the relevant region.

Chromosomes, Human, Pair 22↗
PubMed1995

Potential linkage for schizophrenia on chromosome 22q12-q13: a replication study.

In an attempt to replicate a potential linkage on chromosome 22q12-q13.1 reported by Pulver et al. [1994: Am J Med Genet 54:36-43], we have analyzed 4 microsatellite markers which span this chromosomal region, including the IL2RB locus, for linkage with schizophrenia in 30 families from Israel and Germany. Linkage analysis by pairwise lod score analysis as well as by multipoint analysis did not provide evidence for a single major gene locus. However, a lod score of Zmax = 0.612 was obtained for a dominant model of inheritance with the marker D22S304 at recombination fraction 0.2 by pairwise analysis. In addition, using a nonparametric method, sib pair analysis, a P value of 0.068 corresponding to a lod score of 0.48 was obtained for this marker. This finding, together with those of Pulver et al. [1994: Am J Med Genet 54:36-43] and Coon et al. [1994: Am J Med Genet 54:72-79], is suggestive of a genetic factor in this region, predisposing for schizophrenia in a subset of families. Further studies using nonparametric methods should be conducted in order to clarify this point.

Chromosomes, Human, Pair 22↗
PubMed2004

Effects of combination of Caiapo with other plant-derived substance on anti-diabetic efficacy in KK-Ay mice.

B. Ludvik et al., have recently shown the effect of Caiapo (Ipomoea batatas L.) on reducing fasting blood glucose and insulin resistance in type-2 diabetic patients. It, however, was required 2-4 weeks after the single administration of Caiapo. The present study aimed to determine if the combination therapy of Caiapo with a mulberry leaf powder, which inhibits alpha-glucosidase, or with a loquat leaf extract, which shows an insulin-like effect, could make it possible to enhance the antidiabetic activities of Caiapo, and to shorten the time necessary for the inhibition of increasing blood glucose levels. A mixture of the pulverized tuber of Caiapo (357 mg/kg) and the mulberry leaf powder (143 mg/kg), or a mixture of the pulverized skin of Caiapo (194 mg/kg) and the powdered loquat leaf extract (6 mg/kg) was orally administered to 6 weeks-old male KK-Ay mice for 28 days and the glucose loading test was conducted every 7 days. In the glucose loading test after one week feeding, a reduction in blood glucose concentration after 60 minutes of the administration of glucose was observed in both mixture groups against the control group (p < 0.05) in the case of Caiapo only, similar delayed effects were seen in 2-3 weeks after feeding.

Animals↗
PubMed2004

The ability of konjac-glucomannan to suppress spontaneously occurring dermatitis in NC/Nga mice depends upon the particle size.

Konjac glucomannan (GM) is a well-known dietary fiber with various beneficial functions, which the higher viscous GM is proposed to have the stronger potencies. Application of highly viscous GM to various food industries is limited for the sake of long elapsed time required to solubilize the GM. Thus, the exploration into any physiological function of low-viscous GM remained undone for a long time. Male 4-week-old NC/Nga mice, a model of atopic dermatitis (AD), were fed for 8 weeks on diets containing 5% each of a high-viscous GM powder, ordinary konjac or highly purified GM, and a low-viscous GM powder, pulverized GM or re-granulated fine GM. Striking suppression to the aggravation of dermatitis and the increases in scratching behaviors and IgE levels was significantly observed only in mice fed on the pulverized GM diet, but not in mice fed on the other GM diets or a control diet. We concluded that the low-viscous GM possesses a novel immunoregulatory function and the intensity of the function depends upon the particle size rather than the viscosity.

Animals↗
PubMed1988

Induction of chromosome aberrations and mitotic arrest by cytomegalovirus in human cells.

Human cytomegalovirus (CMV) is potentially an effective but often overlooked genotoxic agent in humans. We report here evidence that indicates that infection by CMV can induce chromosome alterations and mitotic inhibition. The frequency of chromosome aberrations induced was dependent on the input multiplicity of infection (m.o.i.) for human lung fibroblasts (LU), but not for human peripheral blood lymphocytes (PBLs) when both cell types were infected at the GO phase of the cell cycle. The aberrations induced by CMV were mostly chromatid breaks and chromosome pulverizations that resembled prematurely condensed S-phase chromatin. Pulverized chromosomes were not observed in LU cells infected with virus stocks that had been rendered nonlytic by UV-irradiation at 24,000 ergs/mm2 or from infection of human lymphocytes. In LU cells infected with UV-irradiated CMV, the frequency of aberrations induced was inversely dependent on the extent of the exposure of the CMV stock to the UV-light. In permissive CMV infection of proliferating LU cells at 24 hr after subculture, a high percentage (greater than 40%) of the metaphase cells were arrested at their first metaphase and displayed severely condensed chromosomes when harvested 48 hr later. A significant increase (p less than 0.05) in the chromosome aberration frequency was also observed. Our study shows that CMV infection is genotoxic to host cells. The types and extent of damage are dependent on the viral genome expression and on the cell cycle stage of the cells at the time of infection. The possible mechanisms for induction of chromosome damage by CMV are discussed.

Cell Division↗
PubMed1977

Pharmaceutical applications of solid dispersion systems: X-ray diffraction and aqueous solubility studies on griseofulvin-polyethylene glycol 6000 systems.

The X-ray diffraction method was used to characterize physiochemical properties of griseofulvin dispersed in polyethylene glycol 4000 and 6000. Results indicate a negligible or very limited solid solubility of griseofulvin in the pulverized solid dispersions. Pulverization and aging had pronounced effects on the X-ray diffraction spectrum. Results from aqueous solubility studies of griseofulvin in various concentrations of polyethylene glycol 6000 further indicate weak or insignificant interactions between the drug and the carrier. Mechanisms are postulated to account for the reported marked enhancement of dissolution rates and oral adsorption of griseofulvin dispersed in these carriers.

Chemistry, Pharmaceutical↗