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PubMed2005

Evolution of porosity in geotechnical composites.

Nuclear magnetic resonance (NMR) (H1) transverse relaxation measurements were carried out on 37x70-mm cylindrical mineral/organic composites to determine and monitor the porosity evolution. Porosity is related, in principle, to the stability of such materials in geotechnical applications, for example, engineering foundations. The specimens represented novel formulations of mixed "wastes" containing coarse screened mineral, digested sewage sludge, quicklime, and pulverized fuel ash mixed and compacted together to form mechanically competent material. The measurements on a selected formulation indicated initially low porosity (<12%) that becomes lower over 6 months ( approximately 8%) due to pozzolanic reactions occurring. A relaxation time cutoff of 1.5 ms between "bound" and 'mobile' pore water much lower than sandstones (33 ms) was observed. The results confirmed that the NMR method allows a more reliable assessment of porosity and pore-size evolution.

Biotechnology↗
PubMed2004

Protective effects of ursodeoxycholic acid against 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced testicular damage in mice.

The protective effect of ursodeoxycholic acid (UDCA), a biliary component found in bears, on 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced testicular damage in mice was investigated. Fifty C57BL/6J mice were equally divided into five groups. The mice in the control group received the vehicle and standard chow. The single TCDD treatment group received 27.5 microg/kg of TCDD subcutaneously. The UDCA-included treatment group received pulverized chow containing 0.125%, 0.25% and 0.5% UDCA, respectively, for 70 days starting 10 days before TCDD injections. The body and testicular weights were shown to be decreased in the single TCDD treatment group, while the decrease was prevented by UDCA added to the chow. In addition, the decrease in the serum-luteinizing hormone (LH) or the follicle stimulating hormone (FSH) secondary to a TCDD injection was not observed in the UDCA-included treatment group. Contrary to the single TCDD treatment group, the germinal epithelium and intercellular space were relatively well preserved in the UDCA-included treatment group. Adding UDCA also normalized TCDD-induced irregular ultrastructural changes such as development of phagolysosomes, inflated smooth endoplasmic reticulum (SER), dilated and altered mitochondria, necrosis and completely damaged seminiferous tubules. Moreover, in the experiment for Arnt expression, UDCA added to the chow suppressed the TCDD-induced relocation of Arnt from the cytoplasm to the nuclei. In conclusion, TCDD-induced testicular toxicity was effectively protected by UDCA. There was almost complete recovery of the testes in the UDCA-included treatment group. Thus, UDCA may be useful for the prevention and treatment of TCDD-induced testicular damage.

Animals↗
PubMed2005

Induction of neutralizing antibodies by a tobacco chloroplast-derived vaccine based on a B cell epitope from canine parvovirus.

The 2L21 epitope of the VP2 protein from the canine parvovirus (CPV), fused to the cholera toxin B subunit (CTB-2L21), was expressed in transgenic tobacco chloroplasts. Mice and rabbits that received protein-enriched leaf extracts by parenteral route produced high titers of anti-2L21 antibodies able to recognize the VP2 protein. Rabbit sera were able to neutralize CPV in an in vitro infection assay with an efficacy similar to the anti-2L21 neutralizing monoclonal antibody 3C9. Anti-2L21 IgG and seric IgA antibodies were elicited when mice were gavaged with a suspension of pulverized tissues from CTB-2L21 transformed plants. Combined immunization (a single parenteral injection followed by oral boosters) shows that oral boosters help to maintain the anti-2L21 IgG response induced after a single injection, whereas parenteral administration of the antigen primes the subsequent oral boosters by promoting the induction of anti-2L21 seric IgA antibodies. Despite the induced humoral response, antibodies elicited by oral delivery did not show neutralizing capacity in the in vitro assay. The high yield of the fusion protein permits the preparation of a high number of vaccine doses from a single plant and makes feasible the oral vaccination using a small amount of crude plant material. However, a big effort has still to be done to enhance the protective efficacy of subunit vaccines by the oral route.

Administration, Oral↗
PubMed2004

Influence of aggregate pre-wetting and fly ash on mechanical properties of lightweight concrete.

This study has examined the mechanical properties of lightweight aggregate concrete with a density of 1800 kg/m3. The effects of the following parameters on the concrete properties have been analyzed: the pre-wetting time of the lightweight aggregate and the percentage of pulverized fly ash used as cementitious replacement material. The strength of the lightweight aggregate was found to be the primary factor controlling the strength of high-strength lightweight concrete. An increase in the cementitious content from 420 to 450 kg/m3 does not significantly increase the strength of lightweight aggregate concrete. The relationship between the flexural and compressive strength at 28 days can be represented by the equation fr=0.69/fck. The elastic modulus was found to be much lower than that of normal weight concrete, ranging from 15.0 to 20.3 GPa. The addition of PFA increases the slump and density of lightweight aggregate concrete.

Carbon↗
PubMed2004

Use of rubber and bentonite added fly ash as a liner material.

In many countries regulations require all hazardous waste disposal facilities to be lined with suitable impermeable barriers to protect against contamination. In this study, a series of laboratory tests on rubber and bentonite added fly ash were conducted. The aim of the tests was to evaluate the feasibility of utilizing fly ash, rubber and bentonite as a low hydraulic conductivity liner material. Type C fly ash was obtained from Soma thermal power plant in Turkey; rubber in pulverized form was waste from the retreading industry. To investigate the properties of rubber and bentonite added fly ash, hydraulic conductivity, leachate analysis, unconfined compression, split tensile strength, one-dimensional consolidation, swell and freeze/thaw cycle tests were performed. The overall evaluation of results have revealed that rubber and bentonite added fly ash showed good promise and a candidate for construction of a liner.

Bentonite↗
PubMed2005

Pretreatment of municipal solid waste prior to landfilling.

An outdoor pilot-scale study was undertaken to pretreat municipal solid waste by windrow composting. The raw waste was introduced to active composting without any source separation or pulverization. Pretreatment indicators were developed and used as a tool to measure the optimum level of sorting and waste stabilization. The moisture content of the waste dropped from 68% to 61% and the pile attained a thermophilic temperature in one week. It was observed that the C/N ratio, pH profile and temperature gradients were comparable to that of traditional windrow composting. Within one week of active bulk composting, the easily degradable organic matter was consumed and there was a significant reduction in the bulk volume of the mixed waste. The pre-composted wastes were then sorted into four fractions. Compared to the initial untreated waste, the pretreated waste showed greater sorting efficiency and reduced volatile solids. A 1-m(3) cage was used to study pile settlement and volume reduction. The results indicate that pretreatment by bulk composting could reduce by approximately 40% the total mass of waste hauled to landfill sites in developing countries.

Bacteria, Aerobic↗
PubMed2006

Characterization of char derived from various types of solid wastes from the standpoint of fuel recovery and pretreatment before landfilling.

Carbonization is a kind of pyrolysis process to produce char from organic materials under an inert atmosphere. In this work, chars derived from various solid wastes were characterized from the standpoint of fuel recovery and pretreatment of waste before landfilling. Sixteen kinds of municipal and industrial solid wastes such as residential combustible wastes, non-combustible wastes, bulky wastes, construction and demolition wastes, auto shredder residue, and sludges were carbonized at 500 degrees C for 1h under nitrogen atmosphere. In order to evaluate the quality of char as fuel, proximate analysis and heating value were examined. The composition of raw waste had a significant influence on the quality of produced char. The higher the ratio of woody biomass in waste, the higher heating value of char produced. Moreover, an equation to estimate heating value of char was developed by using the weight fraction of fixed carbon and volatile matter in char. De-ashing and chlorine removal were performed to improve the quality of char. The pulverization and sieving method seems to be effective for separation of incombustibles such as metal rather than ash. Most char met a 0.5 wt% chlorine criterion for utilization as fuel in a shaft blast furnace after it was subjected to repeated water-washing. Carbonization could remove a considerable amount of organic matter from raw waste. In addition, the leaching of heavy metals such as chrome, cadmium, and lead appears to be significantly suppressed by carbonization regardless of the type of raw waste. From these results, carbonization could be considered as a pretreatment method for waste before landfilling, as well as for fuel recovery.

Carbon↗
PubMed2004

Column experiments for microbiological treatment of acid mine drainage: low-temperature, low-pH and matrix investigations.

The lifetime of traditional sulfate-reducing bacteria (SRB) bioreactors that utilize a source of reducing equivalents contained within the matrix (e.g. manure) is limited by the amount of readily available reducing equivalents within that matrix. In order to extend bioreactor lifetime indefinitely, the addition of known concentrations of alternative reducing equivalents (methanol and ethanol) to a depleted matrix was tested at low pH and low temperatures. Following acclimation, up to 100% efficiencies of reducing equivalents were directed toward sulfate reduction. Alcohol was added in stoichiometric concentrations to remove 50% of the added sulfate (900 mg/L), producing sufficient sulfide to precipitate all of the iron from solution. An average of 42% of the sulfate was removed following acclimation, reflecting 84% efficiency. An average of 93% of the iron was removed (93 mg/L). Bacteria acclimated to ethanol more rapidly than methanol, although both alcohols were effective as carbon sources. Efficient treatment was observed at the lowest temperatures (6 degrees C) and lowest pHs (pH=2.5) tested. The use of ethanol-fed, highly permeable bioreactor matrices of wood chip, pulverized plastic and rock was also examined to determine which of these porous matrices could be implemented in a field bioreactor. Results indicated that >95% of the 100mg/L iron added was removed by all matrices. Sufficient reducing equivalents were added to remove 450 mg/L of sulfate, wood and rock matrices removed approximately 350 mg/L plastic removed approximately 225 mg/L. A study comparing rock size indicated that small rocks removed iron and sulfate more efficiently than medium- and large-size rocks. The results suggest that wood and rock in conjunction with ethanol are viable alternatives to traditional bioreactor matrices. These findings have direct application to semi-passive sustained operation of SRB bioreactors for treatment of acidic drainage at remote sites.

Bioreactors↗
PubMed2000

Chromogenic in situ hybridization: a practical alternative for fluorescence in situ hybridization to detect HER-2/neu oncogene amplification in archival breast cancer samples.

Determination of HER-2/neu oncogene amplification has become necessary for selection of breast cancer patients for trastuzumab (Herceptin) therapy. Fluorescence in situ hybridization (FISH) is currently regarded as a gold standard method for detecting HER-2/neu amplification, but it is not very practical for routine histopathological laboratories. We evaluated a new modification of in situ hybridization, the chromogenic in situ hybridization (CISH), which enables detection of HER-2/neu gene copies with conventional peroxidase reaction. Archival formalin-fixed paraffin-embedded tumor tissue sections were pretreated (by heating in a microwave oven and using enzyme digestion) and hybridized with a digoxigenin-labeled DNA probe. The probe was detected with anti-digoxigenin fluorescein, anti-fluorescein peroxidase, and diaminobenzidine. Gene copies visualized by CISH could be easily distinguished with a x40 objective in hematoxylin-stained tissue sections. HER-2/neu amplification typically appeared as large peroxidase-positive intranuclear gene copy clusters. CISH and FISH (according to Vysis, made from frozen pulverized tumor samples) correlated well in a series of 157 breast cancers (kappa coefficient, 0.81). The few different classifications were mostly because of low-level amplifications by FISH that were negative by CISH and immunohistochemistry with monoclonal antibody CB-11. We conclude that CISH, using conventional bright-field microscopy in evaluation, is a useful alternative for determination of HER-2/neu amplification in paraffin-embedded tumor samples, especially for confirming the immunohistochemical staining results.

Archives↗
PubMed1987

Comparative lung immunotoxicity of inhaled quartz and coal combustion fly ash.

Some inhaled particles that are deposited in the terminal airways and alveoli clear to the lung-associated lymph nodes, and insoluble particles have a long half-life in these tissues. Because the lung-associated lymph nodes are essential in the induction of immunity after lung immunization, the accumulation of inhaled particles in these tissues could alter immune responses that develop after lung immunization. This study evaluated the effects of inhaled insoluble fly ash particles or alpha quartz on the immune functions of lung-associated lymph nodes. F344 rats were exposed for 20 days by inhalation of fly ash from a fluidized bed combustor (FBC) or a pulverized coal combustor (PCC). Rats were similarly exposed to quartz particles (Min-U-Sil). Control rats were exposed to filtered air. Groups of ten exposed and ten control rats from each group were immunized by intratracheal instillation of 10(8) sheep red blood cells at 4, 6, 40, and 52 weeks after the start of exposures. The cellularity of the lung-associated lymph nodes and antibody-mediated immunity were evaluated at 7 days after immunization. Tissues from lung and lung-associated lymph nodes were taken for histopathology. The inhalation of FBC fly ash, PCC fly ash, and quartz particles all significantly increased the number of lymphoid cells in the lung-associated lymph nodes at each of the sacrifice times. However, FBC fly ash had no significant effect on antibody immunity, while both PCC fly ash and quartz caused suppression of antibody responses at 52 weeks after the start of exposure. Histopathology data showed that exposure to quartz and PCC fly ash caused significant cellular changes in lungs and lung-associated lymph nodes, while FBC fly ash had less effect. These data indicate that an acute exposure (20 days) to relatively insoluble particles significantly increased the cellularity of the lung-associated lymph nodes for up to 52 weeks after the start of the exposure, but the pulmonary toxicity of the particles inhaled appeared to influence the effects of the exposure on antibody immune responses.

Animals↗
PubMed2002

Characterization and solubility study of solid dispersions of flunarizine and polyvinylpyrrolidone.

Flunarizine is a selective calcium entry blocker poorly water-soluble. In this report, the interactions of this drug with polyvinylpyrrolidone in solid dispersions, prepared according to the dissolution method using methanol as the solvent, have been investigated. For purposes of comparison physical mixtures were prepared by simple mixture and homogeneization of the two pulverized components. Combinations of flunarizine/polyvinylpyrrolidone of the following percentage proportions were prepared: 10/90, 20/80, 30/70, 40/60, 50/50, 60/40 and 80/20 (mean particle size of 0.175 mm). The physicochemical properties of solid dispersions were investigated with X-ray diffraction, infrared spectroscopy, differential scanning calorimetry and solubility in equilibrium. X-ray patterns and differential scanning calorimetry have shown that polyvinylpyrrolidone inhibits the crystallization of flunarizine when percentages drug/polymer are 10/90, 20/80 and 30/70. The infrared spectra suggest that there was no chemical interaction between flunarizine and polyvinylpyrrolidone. Equilibrium solubility studies showed that drug solubility was enhanced as the polymer content increased. In general, the solubility increase was greater in solid dispersions than in physical mixtures and the solubility in equilibrium for solid dispersions and physical mixtures at the same drug/polymer proportion showed significant differences (P < 0.05).

Calcium Channel Blockers↗
PubMed1991

Preimplantation genetics: chromosomes of fragmented human embryos.

STUDY OBJECTIVE: To examine the chromosome makeup of fragmented human embryos. DESIGN: Prospective. SETTING: Assisted reproductive technology (ART) program. PATIENTS: One hundred twenty-one poor-quality embryos from 58 patients 31 to 40 years of age admitted for an ART program were examined for chromosome makeup. RESULTS: Chromosome anomalies were observed in 31.9% (29/91) of poor-quality embryos, 19.8% (18/91) displayed mosaicism (diploid/haploid, diploid/triploid, diploid/aneuploid), 5.5% (5/91) showed polyploidy, 2.2% (2/91) had pulverized chromosomes, 2.2% (2/91) revealed aneuploidy, 1.1% (1/91) had prematurely condensed chromosomes, and 1.1% (1/91) had structural rearrangements involving chromosome number 2. The mean age of patients showing anomalies (36.5 years) was not significantly higher than the mean for the entire group (35.5 years). CONCLUSIONS: The incidence of chromosome anomalies in fragmented human embryos is high. These anomalies originate either in the gametes or through mitotic nondisjunction within the embryos. It is not advisable to replace such embryos into patients going through in vitro fertilization.

Adult↗
PubMed1992

Fertilization, cleavage, and cytogenetics of 48-hour zona-intact and zona-free human unfertilized oocytes reinseminated with donor sperm.

OBJECTIVE: To examine the fertilization rates of 48-hour unfertilized oocytes inseminated with fertile donor sperm and to evaluate the cleavage and cytogenetics of ensuing embryos. DESIGN: Prospective. SETTING: Assisted reproductive technology (ART) program. PATIENTS: Four hundred ninety-seven unfertilized oocytes from 97 ART patients were categorized into four groups. A (zona-intact) and B (zona-free) were from patients with partial fertilization failure, whereas C (zona-intact) and D (zona-free) were total fertilization failures. RESULTS: Fertilization rates in groups A and B were significantly higher than C and D (33.2% to 60.9% versus 20.0% to 48.1%; P less than 0.01). Zona-free oocytes had higher fertilization rates than zona-intact oocytes (48.1% to 60.9% versus 20.0% to 32.2%). Multiple pronuclei were high in zona-free oocytes (33.1% to 41.3%). Forty-eight to 54% of embryos generated after donor insemination had chromosome anomalies (mosaicism, aneuploidy, pulverization). CONCLUSIONS: One cause of total fertilization failure appears to lie in intrinsic oocyte problems confined to the zona and oolemma. The fertilization of 48-hour unfertilized oocytes may be of some value in diagnosing fertilization failure in ART patients.

Cell Division↗
PubMedDate not supplied

Seasonality and infectious disease in schizophrenia: the birth hypothesis revisited.

Research literature supports the notion that more people diagnosed with schizophrenia are born during the winter months than other seasons [O'Hare A, Walsh D, Torrey F. Seasonality of schizophrenia births in Ireland. Br J Psychiatry 1980;137:74 7; Pulver AE, Stewart W, Carpenter WT, Jr., Childs B. Risk factors in schizophrenia: season of birth in Maryland, USA. Br J Psychiatry 1983;143:389-96.]. Researchers have postulated that this surge in winter-birth schizophrenia may be related to increases in viral infectious such as influenza and measles [Watson CG, Kucala T, Tilleskjor C, Jacobs L. Schizophrenic birth seasonality in relation to incidence of infectious diseases and temperature extremes. Arch Gen Psychiatry 1984:41:85-90; Mednick SA, Machon RA, Huttunen MO, Bonnett D. Adult schizophrenia following prenatal exposure to an influenza epidemic. Arch Gen Psychiatry 1988;45:189-92.]. However, data supporting significant relationships between infectious disease and schizophrenia incidence has been equivocal [Kendell R, Kemp I. Maternal influenza in the etiology of schizophrenia. Arch Gen Psychiatry 1989;46:878-82; McGrath J, Castle D. Does influenza cause schizophrenia? A five year review. Aust N Z J Psychiatry 1995;29:23-31.]. The purpose of this study was to replicate and expand previous studies by examining seasonal and infectious disease influences on schizophrenia prevalence. It was hypothesized that: (1) there would be an increase in schizophrenia prevalence during the winter months; and (2) that a significant amount of variability in schizophrenia birthrates would be accounted for by rates of influenza and measles. A Georgia Medicaid database (N = 746,615) and statewide infectious disease tables were used to identify correlations. Medicaid recipients were divided into schizophrenia (n = 11,736) and non-schizophrenia (n = 734,879) groups. A ratio of schizophrenic recipients to non-schizophrenic recipients was calculated for each birth cohort represented by each month of the year from 1948-1965. Multiple regression analyses indicated a significant relationship between winter season and schizophrenia incidence. However, neither influenza nor measles was predictive of schizophrenia prevalence. These findings were made using one of the largest sample of schizophrenic individuals in the literature to date. Limitations of the study are discussed, including the use of seasonal and prevalence correlations without data on patient linked maternal infections.

Adult↗
PubMed1988

Bacteriuria following extracorporeal shock wave lithotripsy of infection stones.

Extracorporeal shock wave lithotripsy effectively pulverizes infected (struvite) renal calculi. However, after treatment minute residual fragments that may harbor bacteria and cause persistent bacteriuria remain in the renal collecting system for months. We investigated prospectively the incidence of persistent Proteus mirabilis bacteriuria after extracorporeal shock wave lithotripsy among 15 consecutive women with Proteus mirabilis urinary tract infections and struvite calculi. All patients received parenteral gentamicin for 3 to 8 days (mean 4.7 days) immediately before and after extracorporeal shock wave lithotripsy. Oral antimicrobials then were administered for 14 to 34 days (mean 25 days). Ten patients have maintained a sterile urine or experienced urinary reinfection by other organisms during 8 to 19 months (mean 13 months) of subsequent bacteriological surveillance. Of these 10 patients 9 had residual fragments. Five patients had Proteus mirabilis bacteriuria after 1 to 7 months of surveillance, including 3 with residual fragments. The mean stone size, methods and duration of renal drainage procedures, and duration of antimicrobial therapy were similar for the 2 patient groups. Proteus mirabilis was isolated from the cultures of only 3 of 11 retrievable stone fragments. In contrast to intact infected renal calculi, residual stone fragments after extracorporeal shock wave lithotripsy often are susceptible to sterilization with antimicrobials.

Adult↗
PubMed1988

The role of silicone ureteral stents in extracorporeal shock wave lithotripsy of large renal calculi.

Between November 1984 and December 1985 extracorporeal shock wave lithotripsy was used to treat 1,645 kidneys at our institution. A total of 646 kidneys with stone burden greater than 14 mm. was evaluated with regard to the impact of silicone ureteral stents in post-extracorporeal shock wave lithotripsy morbidity. Our results indicate that small stones were pulverized and eliminated with minimum morbidity. Larger stones frequently were associated with post-treatment ureteral obstruction by sand and fragments. Of 283 kidneys with stone burden exceeding 25 mm. pretreatment placement of silicone ureteral stents reduced complications from 26 to 7 per cent and auxiliary procedure rates from 15 to 6 per cent. Silicone ureteral stents protect the kidney from ureteral obstruction, and allow for safe and effective extracorporeal shock wave lithotripsy of large renal calculi.

Catheters, Indwelling↗
PubMed1988

A new alternative treatment for entrapped stone basket in the distal ureter.

We describe an alternative method for the treatment of an entrapped stone basket. When efforts to remove an engaged stone through the intramural ureter met with marked resistance, the basket with the stone within it was advanced into the renal pelvis. Extracorporeal shock wave lithotripsy then was used to pulverize the stone, allowing successful removal of the basket.

Adult↗
PubMed1988

Extracorporeal shock wave lithotripsy in the prone position: treatment of stones in the distal ureter or anomalous kidney.

A total of 15 patients underwent ESWL using the Dornier HM3 lithotriptor with the patient in the prone position. The stones were in the distal ureter over the sacroiliac joint in 10 patients, 8 of whom had undergone unsuccessful ureteroscopic manipulation. Two patients had horseshoe kidneys with stones that were too anterior to permit accurate targeting with the patient in the standard supine position. One patient had a solitary stone in a pelvic kidney and 1 had an obstructing ureteropelvic junction stone in a crossed ectopic kidney. The final patient had a reconstructed lower urinary tract with a stone at 1 of the ureterointestinal anastomoses. Excellent pulverization was achieved in all patients after only 1 prone ESWL treatment. One patient required temporary percutaneous nephrostomy after ESWL and 1 may require retrograde manipulation of fragments at the ureterovesical junction. No patient had melena, and other than temporary ileus in 1 patient who had concurrent supine ESWL of renal calculi, no gastrointestinal complications were seen. All but 1 patient were free of stones 1 month after prone ESWL. Prone ESWL prevents blockage of shock wave energy by the bony pelvis, because the shock waves enter anteriorly and exit posteriorly. ESWL with the patient in the prone position is a safe and effective treatment of calculi in the distal ureter or anomalous kidney.

Adult↗