Bcl-2 and p53 immunoprofile in Kaposi's sarcoma.
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Seventy three cases of Kaposi's sarcoma (KS) from the 3 histological subtypes (patch, plaque and nodular) were assessed for bcl-2 and p53 protein expression. The aim was to determine the level of expression of these proteins in KS and in the different subtypes. Commercially available antibodies to bcl-2 and p53 were applied after both microwave and pressure cooking antigen retrieval. Bcl-2 immunoexpression increased from the patch stage (36%) to the plaque stage (45%) to the nodular stage (70.83%). Better immunostaining for bcl-2 was obtained after pressure cooking. p53 on the other hand, was not expressed in the patch or plaque stages, but 54.16% of cases in the nodular stage were immunopositive. These results show a progression of immunoexpression of both bcl-2 and p53 from the early histological stages to the late tumor stage, implying that these proteins are upregulated late in the evolution of KS. (+info)
Heating garlic inhibits its ability to suppress 7, 12-dimethylbenz(a)anthracene-induced DNA adduct formation in rat mammary tissue.
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The present studies compared the impact of heating, either by microwave or convection oven, on the ability of garlic to reduce the in vivo bioactivation of 7,12-dimethylbenz(a)anthracene (DMBA) in 55-d-old female Sprague-Dawley rats. In study 1, rats were fed a semipurified casein-based diet and treated by gastric gavage thrice weekly for 2-wk with crushed garlic (0.7 g in 2 mL corn oil) or the carrier prior to DMBA treatment (50 mg/kg body weight). Providing crushed garlic reduced by 64% (P < 0.05) the quantity DMBA-induced DNA adducts present in mammary epithelial cells compared to controls. In study 2, microwave treatment for 60 s, but not 30 s, decreased (P < 0.05) the protection provided by garlic against DMBA-induced adduct formation. In study 3, allowing crushed garlic to stand for 10 min prior to microwave heating for 60 s significantly (P < 0.05) restored its anticarcinogenic activity. Microwave heating of garlic for 30 s resulted in a 90% loss of alliinase activity. Heating in a convection oven (study 4) also completely blocked the ability of uncrushed garlic to retard DMBA bioactivation. Study 5 revealed that providing either 0.105 micromol diallyl disulfide or S-allyl cysteine by gastric gavage thrice weekly for 2 wk was effective in retarding DMBA bioactivation but isomolar alliin was not. These studies provide evidence that alliinase may be important for the formation of allyl sulfur compounds that contribute to a depression in DMBA metabolism and bioactivation. (+info)
Rapid conditions for the cleavage of oligodeoxyribonucleotides from cis-diol-bearing universal polymer supports and their deprotection.
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Two sets of deprotection conditions have been evolved for the deprotection of oligodeoxyribonucleotides and their cleavage from commercially available cis -diol group-bearing universal polymer supports. In the first case, oligodeoxyribonucleotides anchored on the universal support were subjected to one of the standard deprotection conditions followed by treatment with aqueous 0.5 M sodium chloride + 0.2 M sodium hydroxide solution for 30 min at room temperature. In the second case, oligonucleotides bound to the universal support were treated with methanolic sodium hydroxide solution under microwave radiation to obtain fully deprotected oligomers within 4 min. Under both conditions, the cleavage of oligonucleotides from the support and their deprotection occurred quantitatively without any side product formation. The cleaved oligonucleotides were found to be identical in all respects (retention time on HPLC and biological activity in PCR) to the corresponding standard oligo-nucleotides. (+info)
Spectroscopic determination of the water pair potential.
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A polarizable water pair potential was determined by fitting a potential form to microwave, terahertz, and mid-infrared (D2O)2 spectra through a rigorous calculation of the water dimer eigenstates. It accurately reproduces most ground state vibration-rotation-tunneling spectra and yields excellent second viral coefficients. The calculated dimer structure and dipole moment are very close to those determined from microwave spectroscopy and high-level ab initio calculations. The dimer binding energy and acceptor switching and donor-acceptor interchange tunneling barriers are in excellent agreement with recent ab initio theory, as are cyclic water trimer and tetramer structures and binding energies. (+info)
A new digestion method for recovery of MMMFs from lungs.
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A new tissue digestion method is proposed to recover man-made mineral fibers (MMMFs) from lungs, which is an improved Kjeldahl method using microwaves. Tissue digestion is carried out under five different conditions in this experiment, and the most suitable condition is found as follows; dried rat lung (0.5 g of wet weight) is put into a flask with 0.1 ml of H2SO4 and 2.0 ml of HNO3, and treated by microwaves for 5 min. After the treatment, 1.0 ml of H2O2 is added immediately and the sample is treated again under the same condition. Pure samples of glass fibers and refractory ceramic fibers are treated by this proposed method. Numbers and sizes of the fibers are measured before and after the treatment on enlarged photos taking by a scanning electron microscope. As no significant changes are observed in fiber dimensions and numbers, the proposed method is shown to be applicable to recover these MMMFs from lungs. (+info)
Determination of glutamine in muscle protein facilitates accurate assessment of proteolysis and de novo synthesis-derived endogenous glutamine production.
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BACKGROUND: Results of tracer studies indicate that skeletal muscle contributes to approximately 70% of overall glutamine production in healthy adults; the contribution of de novo synthesis being estimated at approximately 60%. However, measurement of the de novo synthesis rate in muscle tissue requires knowledge of the appearance rate of glutamine in plasma and the quantity of glutamine derived from intracellular proteolysis. Thus, the content of glutamine in muscle protein is a prerequisite for an accurate calculation. OBJECTIVE: The objective of the study was to measure glutamine in muscle protein. DESIGN: Muscle specimens (open biopsies) were obtained from humans (10 men and 4 women), rats (n = 4), cows (n = 4), and pigs (n = 4). Glutamine was assessed via prehydrolysis derivatization, rapid microwave-enhanced acid hydrolysis, and 5-dimethylaminonaphthalene-1-sulfonyl chloride (dansyl chloride) reversed-phase HPLC, and expressed per mg alkali-soluble protein (ASP) and DNA. RESULTS: Glutamine concentrations in muscle cell protein of various species ranged from 41 to 49 microg/mg ASP; the differences were not species related. The combined means (+/-SDs) for the 4 species were 43.6 +/- 4.9 microg/mg ASP and 11.9 +/- 2.0 mg/mg DNA, respectively. In humans, there was no apparent influence of age, sex, or BMI. CONCLUSIONS: Direct and specific measurements of glutamine in intact muscle protein were 50% lower than assumed previously. We used data compiled from earlier studies to recalculate the contributions of proteolysis and de novo synthesis to the endogenous production of glutamine in selected age groups of healthy humans; these contributions remained remarkably constant at approximately 13% and approximately 87%, respectively. (+info)
High-throughput plasmid DNA purification for 3 cents per sample.
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To accommodate the increasingly rapid rates of DNA sequencing we have developed and implemented an inexpensive, expeditious method for the purification of double-stranded plasmid DNA clones. The robust nature, high throughput, low degree of technical difficulty and extremely low cost have made it the plasmid DNA preparation method of choice in both our expressed sequence tag (EST) and genome sequencing projects. Here we report the details of the method and describe its application in the generation of more than 700 000 ESTs at a rate exceeding 16 000 per week. (+info)
Determination of germanium in human specimens: comparative study of atomic absorption spectrometry and microwave-induced plasma mass spectrometry.
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The determination methods of germanium (Ge) in biological specimens such as blood plasma, erythrocytes, urine, hair, nail, and other organs were established using graphite furnace atomic absorption spectrometry (GFAAS) and microwave-induced plasma mass spectrometry (MIP-MS). The detection limits of Ge standard solution were 3 ng/mL with GFAAS and 0.05 ng/mL with MIP-MS. The detection limits in organ samples depended on the type of samples and sampling amounts: 3-30 ng/g by GFAAS and 0.05-0.5 ng/g by MIP-MS. The sensitivity of GFAAS was lower than that of MIP-MS; however, it was adequate for determining Ge concentrations in specimens from patients who had ingested Ge. Samples were digested by a simple wet-ashing procedure using nitric acid and perchloric acid. To avoid the interfering effects of coexisting elements and perchloric acid residue, an extraction method using organic solvent was tried. When using MIP-MS, extraction was not necessary; however, both dilution and addition of an internal standard were needed. Special attention was required for iron-rich samples because a molecular ion of 56Fe16O was observed at nm/z72 where 2Ge was monitored. The results of Ge concentrations in human samples obtained by these methods agreed well. Interfering effects of perchloric acid, which was used for digestion and which remained in samples, were observed in both methods. Hair and nail samples from people who had ingested Ge were useful for monitoring Ge in the body. Hair samples were useful for determining past exposure to Ge when the distribution patterns from the scalp to the end of the strand were analyzed. In control subjects, Ge concentrations in the listed specimens and organs were lower than 0.1 microg/g or mL, and these low levels of Ge were able to be determined by MIP-MS in combination with the extraction method. (+info)