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PubMed1999

Effect of gamma radiation on native endolithic microorganisms from a radioactive waste deposit site.

A time-course experiment was conducted to evaluate the effects of gamma radiation on the indigenous microbiota present in rock obtained from Yucca Mountain, Nevada Test Site. Microcosms were constructed by placing pulverized Yucca Mountain rock in polystyrene cylinders. Continuous exposure (96 h) at a dose rate of 1.63 Gy/min was used to mimic the near-field environment surrounding waste canisters. The expected maximum surface dose rate from one unbreached canister designed to contain spent nuclear fuels is 0.06 Gy/min. Considering the current repository packing design, multiple canisters within one vault, the cumulative dose rate may well approach that used in this experiment. The microbial communities were characterized after receiving cumulative doses of 0, 0.098, 0. 58, 2.33, 4.67, 7.01 and 9.34 kGy. Radiation-resistant microorganisms in the pulverized rock became viable but nonculturable (VBNC) after a cumulative dose of 2.33 kGy. VBNC microorganisms lose the ability to grow on media on which they have routinely been cultured in response to the environmental stress imposed (i.e. radiation) but can be detected throughout the time course using direct fluorescence microscopy techniques. Two representative exopolysaccharide-producing isolates from Yucca Mountain were exposed to the same radiation regimen in sand microcosms. One isolate was much more radiation-resistant than the other, but both had greater resistance than the general microbial community based on culturable counts. However, when respiring cell counts (VBNC) were compared after irradiation, the results would indicate much more radiation resistance of the individual isolates and the microbial community in general. These results have significant implications for underground storage of nuclear waste as they indicate that indigenous microorganisms are capable of surviving gamma irradiation in a VBNC state.

Bacteria↗
PubMed1999

Initial experience with endoscopic holmium laser lithotripsy for pediatric urolithiasis.

PURPOSE: Due to the unavailability of suitable pediatric instruments children have not benefited from advances in endoscopic lithotripsy. This limitation may be overcome by the holmium: YAG laser. We evaluated the indications for, and efficacy and complications of holmium:YAG laser lithotripsy. MATERIALS AND METHODS: We retrospectively reviewed all cases of laser lithotripsy. Access to the calculus was antegrade or retrograde. A solid state holmium:YAG laser was used. RESULTS: Eight patients 4 to 14 years old underwent laser lithotripsy during the study period. Average calculous surface area was 357.13 mm.2 (range 14 to 1,645). Five patients required 1 procedure to render them stone-free, while the remaining 3 required multiple procedures. No complications were associated with laser lithotripsy. CONCLUSIONS: The ability of the holmium:YAG laser to pulverize urinary calculi makes it an alternative choice for lithotripsy. In our series all patients are stone-free with stable renal function. The advantages of the holmium:YAG laser are that it may be precisely applied via small fibers, and it pulverizes calculi with minimal scattering of energy and retropulsion of the calculus, decreasing trauma to tissues at the perioperative site. There is also a lower risk of residual fragments, which is associated with a lower incidence of calculous regrowth. Holmium: YAG laser is safe and effective for treating pediatric urolithiasis.

Adolescent↗
PubMed1999

Use of polymerase chain reaction to detect Proteus mirabilis and Ureaplasma urealyticum in urinary calculi.

In this study, we evaluated the efficacy of the polymerase chain reaction (PCR) in detecting urea-splitting microorganisms in desiccated urinary tract infection stones. Seventy-eight urinary tract stones were tested for the presence of Proteus mirabilis and Ureaplasma urealyticum by means of PCR with species-specific primers. Twenty-seven stone samples were composed of struvite and/or carbonate apatite (infection stone); 40 were calcium oxalate and/or calcium phosphate; seven were mixed, with struvite/carbonate apatite and calcium oxalate; and four were uric acid stones. PCR was performed with DNA extracted from pulverized stone pieces. Initial assays using the pulverized stone specimens spiked with microorganisms showed that PCR could not detect U. urealyticum at densities below 10(3) color changing units (CCU), or P. mirabilis at densities below 10(4) colony-forming units (CFU). PCR was negative for U. urealyticum and P. mirabilis in all metabolic stones from patients. P. mirabilis was detected by PCR in 10 of 34 patients with infection stones. Preoperative urine cultures grew P. mirabilis in three of these 10 patients, and were negative for P. mirabilis in the other seven. U. urealyticum was detected by PCR in stone samples from four patients, two of which were also PCR-positive for P. mirabilis. All four of these patients had infection stones: two had residual stones, and the other two had recurrence of urinary stones after their operations. These results demonstrate that microorganisms in urinary stones can be detected by PCR even when the voided urine culture is negative. Investigations into the role of bacterial infection in stone formation will require further improvements in the sensitivity of PCR assays for pathogen detection.

Adult↗
PubMedDate not supplied

A technique for extraction and thin layer chromatography visualization of fecal bile acids applied to neotropical felid scats.

Fecal bile acid patterns have been used successfully to identify scats. Neotropical felid scats are capable of this biochemical identification because they present low concentrations of plant pigments that would interfere in fecal bile acids detection. However, neotropical felid scats have poor quantities of bile acids, so we developed in this work a proper technique for their extraction, visualization and determination. Twenty eighth feces of seven different felid species, collected from Zoological and Wildlife Parks, were dried and pulverized. The procedure for analyzing feces is: Take one g of pulverized feces and shake for 3 hr at room temperature in 20 ml benzene:methanol; filter and evaporate to 5 ml. Spot on TLC plate and develop in toluene:acetic acid:water. Dry and visualize with anisaldehyde. Field collected scats could be identified by the bile acids pattern revealed by this specific technique and, then, used as a source of information for distribution, density and food habits studies.

Animals↗
PubMed1975

[Effect of ultraviolet light on human chromosomes (author's transl)].

Lymphocytes were cultured in quartz flasks and irradiated by UV light. Time of exposure and moment of application varied. After UV treatment, pulverization of the chromosomes occurred and larger nuclear fragments which might be products of an abnormally proceeding mitosis with chromatin confluence were observed. The usual chromosome aberrations such as breaks, special segments, abnormal chromosomes and polyploidy have been rarely observed, but are found more often in those cultures where pulverization and nuclear fragments are less abundant. A number of mitoses in the irradiated cultures, however, shows no chromosomal aberrations. The ratio of unaffected to unaffected mitoses is dose-dependent. Chromosome fragmentation can result from UV irradiation occurring at any instance during the time of culture. One finds maximum and minimum amounts of damage when a constant dose is applied at various times.

Cell Nucleus↗
PubMed2003

[The influence of some trace elements on bioaccumulation in tissues and bioenergetic metabolism of the edible snail Helix aspersa maxima as determined by HPLC of purine derivatives].

UNLABELLED: The aim of this work was to determine the bioaccumulation of fluoride and some metals (Cu, Zn, Pb) in tissues of snails under strictly controlled conditions expecting with this approach to verify the hypothesis that snails are suitable for the monitoring of environmental hazards. Additionally, the toxicity of fluorides administered orally on the energy balance of the snail's foot was investigated basing on concentrations of nucleosides, nucleotides and their products measured with high-performance liquid chromatography (HPLC). Two parallel snail cultures were started. The effect of dose on tissue levels of fluoride and metals was studied in the first part of the experiment. The second part served to study the effects of fluoride on energy metabolism of foot muscle (Tab. 1). Quantitation of fluoride and metal levels was done in soft tissues (foot, hepatopancreas) and shells of snails. Qualitative and quantitative analysis of purine compounds was performed in slices of foot. Fluoride concentrations in pulverized shells were measured using an ion-selective electrode. Gas chromatography served to determine fluoride concentrations in soft tissues (hepatopancreas and foot). Concentrations of metals were determined spectrophotometrically. Fluoride and metal content was calculated basing on weight of the pulverized sample. Purines were measured in foot muscle slices with high-performance liquid chromatography (HPLC). Concentrations were adjusted for protein content of sample. Concentrations of the following nucleosides, nucleotides and their products were determined: ATP, ADP, AMP, Ado (adenosine), GTP, GDP, GMP, Guo (guanosine), Hyp (hypoxanthine), IMP, Ino (inosine), Xan (xanthine), Urd (uridine), UA (uric acid), NAD+, and NADP (Fig. 1.). Statistical analysis was done with non-parametric test of Kruskal-Wallis, Mann-Whitney U-test and Spearman Rank Correlation Coefficient. CONCLUSIONS: 1. Accumulation in the shell was significantly increased at the lowest concentration of fluoride, but levels remained below those in the foot or hepatopancreas. It can be inferred that due to low sensitivity, accumulation of fluoride in soft tissues is not a suitable indicator for biomonitoring purposes. Shells seem to be more suited for this aim. 2. Due to low sensitivity, accumulation of metals in soft tissues is not a suitable indicator for biomonitoring purposes. 3. Fluoride had a statistically significant effect on the energy metabolism in muscle, especially on the content of AMP and GMP (Fig. 3, 4). The content of adenylate derivatives was increased (Fig. 3, 4) and phosphorylation of ADP to ATP was inhibited (Fig. 2, 5). 4. An increase in TAN and AEC with 1330 mg F-/kg seems to result from inhibition by fluoride of energy-consuming processes (Fig. 5). 5. In cases of high levels of fluoride it seems reasonable to measure the content of AMP, GMP, Guo or the value of AEC which appear to serve as universal indicators of depressed metabolic function (Fig. 3, 4, 5, 6).

Adenosine Diphosphate↗
PubMed2004

[Extraction of coumarins from Angelica dahurica by supercritical extraction and GC-MS analysis].

OBJECTIVE: To extract coumarins from Angelica Dahurica by supercritical CO2. METHOD: Six-factor and three-level orthogonal experimental design was used to optimize the SFE conditions as guided by the content of total coumarins in the extract. Constituents of the coumarins were analyzed by GC-MS, and their relative contents were determined by normalization method of areas. RESULT: Total 15 coumarins were separated, the relative contents of oxyimperatorin, imperatorin and isoimperatorin being up to 42.40%, 22.14% and 12.12% respectively. Optimum extraction process was established: 21 MPa as extraction pressure, 50 degrees C as extraction temperature, 3 h as time for extraction, 20 mesh as pulverized degree, 6.5 MPa as separation pressure and 30 degrees C as separation temperature. CONCLUSION: Changes in extraction pressure, temperature, time, pulverized degree and separation pressure affect the extracting results remarkably.

Angelica↗
PubMed2006

[Influence of mineral matter on sulfur conversion in coal during combustion].

Three species micro-pulverized coals(Hegang, Tiefa, Zhungeer coal) were studied, the mineral matters (MgO, CaO, Al2O3 and Fe3O4) were respectively added to the coals. The combustion of samples were studied to investigate the effect of mineral matter on transformation of sulfur during combustion by the combined of DTG and GC-MS, the flowmeter 50 mL/min, heating rate 20 degrees C/ min, oxygen volume percentage 20% . The SO2 release curve of primitive micro-pulverized coal appear three peaks during the combustion, but the demineralized sample appear two peaks. The species of coal has effect on temperature of the maximum release rate of SOz, the release rate of SO2 of Hegang coal is even in three temperature ranges, Tiefa coal appear maximum value about 500 degrees C and Zhungeer coal about 200 degrees C which probably due to the different amount of all kinds of sulfur in primitive coal sample. The mineral matter (MgO, CaO, Al2O3 and Fe3O4) have sulfur retention and catalyzing effect on SO2 the combustion of coal. The amount and species of mineral matter and species of coal determine the sulfur retention effect.

Air Pollution↗
PubMed2006

[Study on recovery of copper from waste printed wiring boards by electrostatic separation].

Recovery of Cu from waste printed wiring boards (PWBs) was studied by crushers and electrostatic separator. The results of pulverizing experiment show that liberation degree of metal is higher in grain size -0.9 + 0.074 mm, the product of this grain size can be used as raw material in electrostatic separation. The main factors that influence electrostatic separation are found by dynamic analysis of particles in course of electrostatic separation, it conclude electrode voltage, roller rotate speed, electric coronary polar distance and granularity of particles. The -0.9 + 0.074 mm pulverizing product is separated through single stage electrostatic separation after optimizing influence factors. Result shows that the enrichment condition of Cu in fine material is good, Cu could be concentrated from 32.0% to 63.6%, and recovery ratio is 78.7%.

Copper↗
PubMedDate not supplied

[Lithotripsy of gallbladder calculi with extracorporeal shockwaves].

Two hundred and sixty two patients with gallbladder stones were prospectively evaluated at the Biliary Lithiasis Treatment Unit of the Mater Dei Hospital, Belo Horizonte, MG., and 45 (17.5%) were selected for extracorporal shock wave lithotripsy (ECSWL). From these, 32 were submitted to the procedure. One stone was present in 30 patients, 2 stones in another and 1 patient had 3 stones. The mean diameter was 14.7 mm ranging from 8 to 28 mm. ECSWL was preceded by 1 week course of ursodeoxycholic acid (8 to 10 mg/dk/day) and this medication was continued after the procedure. ECSWL was done with the Lithosthar-Plus apparatus (Siemens). Meperidine (up to 100 mg) IM and pirazolene IV was given when necessary. The intensity of the shock waves was gradually increased to a maximum (9 bar) whenever tolerated. The treatment was well succeeded in 22 cases (71%) with pulverization in 12 (38.7%). In 9 patients (29%) remaining fragments were greater than 4 mm. From these, 3 were submitted to a second session of ECSWL. In 1 patient the stone could not be properly positioned for lithotripsy. The mean number of shock waves was 2,591, ranging from 801 to 4,411. The mean duration of the sessions was 80 min, ranging from 45 to 150 min. In 3 patients, a complete disappearance of fragments was observed in intervals of 1 to 6 months after the procedure. One patient had severe pain during ECSWL and developed acute cholecystitis. One patient had sinus bradycardia. One patient with total stone pulverization, become jaundiced 1 month after ECSWL and a gallbladder carcinoma was found at surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1987

Characterization of chromosome aberrations induced by incubation at a restrictive temperature in the mouse temperature-sensitive mutant tsFT20 strain containing heat-labile DNA polymerase alpha.

tsFT20 cells derived from a mouse mammary carcinoma cell line, FM3A, which has temperature-sensitive DNA polymerase alpha activity (Y. Murakami, H. Yasuda, H. Miyazawa, F. Hanaoka, and M. Yamada, Proc. Natl. Acad. Sci. USA, 82:1761-1765, 1985) were rapidly committed to death after temperature upshift to 39 degrees C. tsFT20 cells synchronized in S phase were more sensitive to the restrictive temperature than exponentially growing cells. In order to gain insight into the processes from the interruption of DNA synthesis to cell death, we analyzed chromosome aberrations induced in tsFT20 cells which had been incubated for 2 or 4 h at the restrictive temperature and then cultured at the permissive temperature. The majority of metaphase cells showed extensive chromosome aberrations such as chromatid gaps, breaks, and exchanges; chromosome pulverizations; their mixed types; and ring chromosomes. Analyses with the use of cell synchronization and autoradiography revealed that chromosome aberrations were induced only in the cells which synthesized DNA during incubation at 39 degrees C. We classified the chromosome aberrations into five types: gap or break type; exchange type; pulverization type; complex type; and ring type. The temporal order of the appearance of these types of chromosome aberrations was found to be the above described order. It was further found that cycloheximide dramatically repressed the induction of chromosome aberrations, and metaphases with many chromosome aberrations exhibited a large number of sister chromatid exchanges. These results indicate that abnormal cessation of DNA replication in tsFT20 cells at the restrictive temperature due to the inactivation of DNA polymerase alpha results in cell death via induction of double-strand breaks which lead to chromosome aberrations as well as sister chromatid exchanges.

Animals↗
PubMed1978

A comparison of procedures to determine free fatty acids in rat heart.

The level of free fatty acids in intact tissues has been found to be low but is known to rise in proportion to the extent of autolysis. Therefore, the high levels of free fatty acid reported in the cardiac lipids of rats fed rapeseed oil were reinvestigated using two different procedures for homogenization. Quick freezing and pulverization at dry ice temperature followed by lipid extraction was found to give lower values of free fatty acids (200 microgram/g of wet heart tissue) than the more commonly used technique of employing rotating blade-type homogenizers (greater than 1700 microgram/g of wet heart tissue). The amount of diglycerides was found to be 3 times greater when the latter method was used. The high levels of free fatty acid and diglyceride suggest that extensive autolysis occurs during homogenization with a rotating blade-type homogenizer. Freezing and pulverization at dry ice temperature is therefore recommended for determining intact lipid classes in rat heart.

Animals↗
PubMed1983

Endocardial tumors in rats exposed to durable fibrous materials.

Endocardial tumors in the rat found in association with intrathoracic implantation of durable fibrous materials are reported here for the first time. In Osborne-Mendel female rats, endocardial tumors occurred in 3 of 50 rats associated with the implantation of fiberglass greater than 5 micron in length and 1-3 micron in diameter, in 1 of 15 rats associated with fiberglass of 0.03 X 3 micron, and in 1 of 15 rats associated with pulverized glass fiber. The intrathoracic administrations of pulverized chrysotile, of cigarette smoke condensate and crocidolite, and of coarse cotton lint, and of intravenous injections of air particulate extract were associated with endocardial tumor in 1 of 15 rats each. The dimensions of the durable fibers associated with endocardial tumors were similar to those of carcinogenic asbestos. Endocardial tumors were not observed in concurrently studied control rats.

Age Factors↗
PubMed1978

Long acting methadone formulations.

Studies conducted in this laboratory have indicated the feasibility of producing long-acting methadone tablets. In examining further, methadone hydrochloride suspensions were developed using spermaceti or eudragit retard-1 for particle coating. These procedures involved the addition of the active compound (methandone hydrochloride) to: a) melted spermaceti which was dried, and the dried mixture was pulverized and added to a methyl cellulose water solution; afterwards wild cherry syrup was added to the suspension, and b) Eudragit retard-1 crystals which were pulverized, dissolved in acetone/isopropanol (1:1) solvent system, dried, and to this product again the suspending agent methyl cellulose was added followed by wild cherry syrup to produce suspensions containing 10, 20, and 30 mg/ml methadone. These formulations were further used for in vivo studies, in male albino rats of Wistar strain. The pain threshold method was utilized in order to determine the duration of methadone. Over 75 h resistance to pain was recorded. Using the same technique, suspensions of methadone-naloxone combinations and the salts methadone-alpha-naphthalenesulfonate and methadone-o-benzoylbenzoate were prepared and examine similarly.

Analgesics↗
PubMed1993

[Role of heat-shock proteins in the recovery of mitotic chromosome damage induced by high temperature in Drosophila melanogaster].

The synthesis of the heat-shock proteins (HSP) and the frequency of the mitotic chromosome damages (pulverizations, chromosome, chromatid stickiness, etc.) was studied in the cells of larva nervous ganglion in the process of recovery after heat shock (37 degrees C, 30 min). Analysis was performed in two strains of Drosophila melanogaster (Canton S-the wild type and the mutant l(1)ts403 with the defect in the HSP system). Correlation between the dynamics of HSP synthesis and the alteration of the chromosome pulverization and stickiness frequency was shown for both Drosophila strains under study. These results, in accord with the data on HSPs' binding to chromosomes following heat shock and their role as molecular chaperones, allowed to suggest that HSPs took part in chromosome condensation and in the recovery of heat shock induced damages leading to chromosome and chromatid stickiness.

Animals↗
PubMed1996

[Consequences of exposure to extreme conditions in somatic cells of Drosophila melanogaster under conditions of disturbed synthesis of heat shock proteins].

Restoration of cell proliferation and repair of chromosome damage (chromatin agglutination, pulverization, or aggregation) in conditions of disturbed synthesis of heat shock proteins (HSPs) was studied in nerve ganglia of Drosophila melanogaster larvae. Two approaches were used to suppress the heat shock response: (1) anaerobic heating of wild-type Canton S larvae at 37 degrees C for 13 min, which temporarily blocked HSP gene expression at the transcriptional level [1], and (2) aerobic heating of mutant l(1)ts403 larvae at 37 degrees C for 30 min, which disturbed HSP gene expression at the posttranscriptional level [2]. The duration of heat treatment was selected according to the period of regression of heat shock puffs [3]. In both experimental systems, the period of HSP synthesis and the delay in resuming cell proliferation and recovering from mitotic chromosome stickiness increased similarly, compared to corresponding positive control. This suggests the involvement of HSPs in repairing chromatin protein damage leading to chromosome stickiness and in resuming cell proliferation. An increase in the number of cells with morphologically abnormal (pulverized or aggregated) chromatin was observed only after heat treatment for 30 min (rather than for 13 min). However, the patterns of changes in the number of such cells in Canton S and l(1)ts403 larvae recovering from 30-min heat treatment differed from one another. Different mechanisms responsible for induction of chromosome abnormalities (premature condensation of interphase chromosomes or disturbed condensation of mitotic chromosomes) and different roles of HSP in these processes are discussed.

Anaerobiosis↗
PubMed1998

Recovery of DNA from human teeth by cryogenic grinding.

DNA has been previously recovered from human teeth for RFLP and PCR-based forensic analysis. In some cases, the maximum amount of undisturbed tooth structure is required for ulterior forensic analysis. But, in most cases, following comprehensive documentation, it is possible to section the tooth longitudinally or horizontally, or crush it to access the DNA-rich core. This technical report describes an alternative method to recover DNA from whole extracted human molar teeth. A 6700 freezer mill was used to pulverize 20 teeth under frozen preparation in liquid nitrogen and sterile conditions. The mean yield of DNA was 30.9 micrograms (18.4 micrograms DNA per gm tooth powder). The resulting fine powder was subjected to organic extraction and subsequently quantified using slot blot hybridization. Aliquots were successfully amplified at three short tandem repeat polymorphic loci. The technique is simple and relatively rapid. Isolation of the samples during pulverization minimizes the risk of contamination.

DNA↗
PubMed1983

Propionibacteria in patients with acne vulgaris and in healthy persons.

A total of 375 anaerobic and microaerophilic coryneform rods, isolated from the pilosebaceous ducts of 26 healthy persons (71 strains) and from comedones (93 strains), pustules (107 strains), and the unaffected skin (104 strains) of 36 acne patients were classified according to the species key in Bergey's manual, the biotyping scheme of Pulverer and ko, the serotyping schedule of Höffer et al., and the phage typing schedule of Jong et al. The statistical evaluation demonstrated certain differences in the frequencies of the Propionibacterium species and types between the different groups tested. Thus, the species P. granulosum was isolated only from acne patients (50.0% of patients examined) and was found more frequently in comedones and pustules than in unaffected follicles in acne patients. The majority of P. granulosum strains belonged to serotype II (95). Biotype A propionibacteria were more frequently found in strains from healthy controls (52.1% of strains) than in strains from healthy controls (52.1% of strains) than in strains from comedones (17.2%), pustules (27.1%) and unaffected skin (38.5%) of the acne patients. The results of phage-typing showed that the P. acnes lysotype I was more frequent in acne patients (total: 73.2% of strains), especially in the inflamed pustules (88.5%), than in healthy controls (55.1%).

Acne Vulgaris↗