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At least 55 records · Page 3Linked to original sources
PubMed2002

Evaluation of Glyde File Prep in combination with sodium hypochlorite as a root canal irrigant.

The purpose of this study using a scanning electron microscope was to investigate the efficacy of four different irrigation techniques after canal preparation with Profile Ni-Ti rotary instruments. A modified technique for the use of Glyde File Prep is proposed. Forty anterior teeth were divided into four groups, instrumented, and irrigated as follows: physiological solution (group A), 2.5% sodium hypochlorite (group B), 2.5% sodium hypochlorite and Glyde File Prep (group C), and 2.5% sodium hypochlorite and Glyde File Prep applied at the end of the preparation with sterile paper points (group D). After scanning electron microscopic evaluation at three different levels, debris, smear layer, and dentinal tubules were scored. Groups A and B had significantly more smear layer and less open tubules on the canal walls compared with the group C and group D samples. Differences in the mean amount of debris between group A samples and other irrigation regimes were statistically significant.

Chelating Agents↗
PubMed1994

The effects of a prenatal course including PREP for effective family living on self-esteem and parenting attitudes of adolescents: a brief report.

Nine adolescent females were enrolled in a prenatal course that included the PREP for Effective Family Living Program (the treatment group). Two comparison groups were utilized in this study; one attended the prenatal group without the PREP program, and the second did not attend either the prenatal course or the PREP program. The Coopersmith Self-Esteem Inventory and the Attitude Toward the Freedom of Children Scale (a parental attitude scale) was administered to all participants. No significant difference was found among the three groups in terms of self-concept. A significant difference was found among the three groups in terms of parental attitudes, with the treatment group scoring higher on democratic parenting attitudes than did the two comparison groups.

Adolescent↗
PubMedDate not supplied

A randomized prospective trial comparing 45 and 90-ml oral sodium phosphate with X-Prep in the preparation of patients for colonoscopy.

Forty-six patients were randomized to receive either 45 or 90-ml oral sodium phosphate (NaP) (Fleet Phospho-Soda), or X-Prep (a Senna preparation) before elective colonoscopy to compare the quality of colon cleansing, ease of preparation, and gastrointestinal intolerance. Before colonoscopy, one of us administered a questionnaire to the patient to assess how well the preparation was tolerated (scale from 1 to 5: 1 = easy, to 5 = unable to finish) and about the presence of four symptoms:abdominal pain, nausea, vomiting, and dizziness. The quality of colon cleansing was graded by two gastroenterologists (1 = excellent, 2 = good, 3 = fair, 4 = poor), who were unaware of how the patient was prepared or tolerated the preparation. The overall quality of bowel preparation with 90-ml oral NaP was better than with X-Prep and 45-ml NaP (p < 0.01). Patients found preparation with NaP to be easier than X-Prep (p < 0.002). No difference was seen in the incidence of abdominal pain, nausea, vomiting or dizziness. In the 90-ml NaP group, a significant rise in sodium and chloride occurred. However, increments were not greater than 5%. Hyperphosphatemia was noted with NaP, but was transient, and no concomitant decrease in calcium was seen. We conclude that, in the groups of patients studied, 90-ml NaP is a safe colonic cleansing agent that is better tolerated and more effective than others.

Administration, Oral↗
PubMed1997

The Q-Prep system: effects on the apparent expression of leucocyte cell surface antigens.

To facilitate the analysis of immunolabelled peripheral blood or bone marrow leucocytes by flow cytometry, a number of reagents are available commercially that lyse erythrocytes and fix leucocytes. This study has investigated the effect on antibody-labelled whole blood of the Q-Prep procedure, in which erythrocytes are lysed with formic acid, and leucocytes are fixed with formaldehyde. Whole blood samples were labelled with the nuclear dye LDS-751 and with antibodies to HLA-DR or belonging to CD2, CD3, CD4, CD7, CD8, CD10, CD13, CD14, CD19, CD20, CD29, CD33, CD45, CD45RA, CD56, and CD62L (TQ-1) that were directly conjugated to either phycoerythrin (PE) and/or fluorescein isothiocyanate (FITC). Leucocytes were analysed by flow cytometry either in unfixed, unlysed whole blood (15) or after preparation using the Q-Prep system. The binding of eight antibodies, CD19-FITC, CD2-PE, CD3-PE, CD4-PE, CD19-PE, CD29-PE, CD45RA-PE, and CD56-PE, to the surface of lymphocytes was reduced, resulting in significant changes (P < 0.05) in the percentages of cells that stained positively and/or their mean molecules of equivalent fluorochrome (MEF). Further analysis revealed that this was due to the formic acid used during the erythrocyte lysis stage.

Antibodies, Monoclonal↗
PubMed1994

Chromatographic separation of low-molecular-mass recombinant proteins and peptides on Superdex 30 prep grade.

The chromatographic properties of Superdex 30 prep grade medium have been investigated in non-denaturing and denaturing mobile phases using commercially available proteins and peptides as well as low-molecular-mass (M(r)) recombinant polypeptides. The medium is a macroreticular gel composed of crosslinked agarose beads to which dextran has been covalently bound. The mean particle size is approximately 34 microns. Experimental results show a linear relation between the distribution coefficient (KD) and the log10 M(r) in the fractionation range 24,000-3000. The relationships between resolution and flow-rate or load volume were investigated and shown to be comparable with those of Superdex 75 and 200 prep grade media. Minimal loss of resolution occurred in the flow-range from 30-60 cm/h. Load volumes of up to 5% total column volume could be applied while maintaining baseline resolution of polypeptide mixtures. Non-specific interactions between the matrix and certain samples were characterized. The predominant interactions with the resin appear to be hydrophobic in nature rather than ionic. Hydrogen bonding may also play a role in the retardation of certain small molecules. The applicability of the resin for separating dimeric and oligomeric forms of low-molecular-mass recombinant proteins was shown.

Amino Acid Sequence↗
PubMed1994

Methods and reagents. On the magic of mini-preps....

Methods and reagents is a unique monthly column that highlights current discussions in the newsgroup bionet.molbio.methds-reagnts, available on the Internet. This month's column discusses the problems encountered by some people when switching from Promega's Magic mini-prep plasmid DNA isolation columns to their new Wizard mini-prep kits. For details on how to partake in the newsgroup, see the accompanying box.

Biotechnology↗
PubMed1995

A comparison of two skin preps used in cardiac surgical procedures.

Postoperative surgical site infections contribute significantly to increased patient morbidity and mortality rates and unnecessary hospital costs. Effective and efficient preoperative patient skin preparation is an important perioperative nursing intervention that decreases the number of wound contaminants and reduces the risks for postoperative surgical site infections. This study examined the effectiveness and time and material costs of two preoperative patient skin prep methods (ie, isopropyl alcohol prep/iodophor-impregnated adhesive drape method, iodophor scrub and paint prep/plain adhesive drape method). The isopropyl alcohol prep/iodophor-impregnated adhesive drape method clinically was as effective as the iodophor scrub and paint prep/plain adhesive drape method, more cost-effective when time and materials were compared, and less cost-effective when materials alone were compared. To make appropriate decisions about the use of preoperative patient skin prep methods, perioperative nurse managers and staff members need to examine and determine whether costs in time or materials have the greater impact on their surgical settings.

1-Propanol↗
PubMed1991

Characterization of synthetic macroporous ion-exchange resins in low-pressure cartridges and columns. Evaluation of the performance of Macro-Prep 50 S resin in the purification of anti-Klenow antibodies from goat serum.

Three ion-exchange materials and one hydrophobic-interaction chromatography packing, based on a rigid macroporous polymer with large, relatively uniform pores, have been evaluated for low-pressure liquid chromatography of antibodies. These sorbents have high capacities for both small and large proteins and are mechanically, chemically, and thermally stable. Macro-Prep 50 S. CM and Q ion-exchange materials are strongly acidic, weakly acidic, and strongly basic, respectively. Protein binding and recovery, pressure-flow properties, and chemical and thermal stability were determined for each sorbent. A rapid, two-step method for the purification of anti-Klenow antibodies from goat serum was developed, based on the Macro-Prep 50 S strong-acid cation-exchange material and the Econo-Pac HIC prepacked hydrophobic-interaction cartridge.

Animals↗
PubMed2006

The closed structure of presequence protease PreP forms a unique 10,000 Angstroms3 chamber for proteolysis.

Presequence protease PreP is a novel protease that degrades targeting peptides as well as other unstructured peptides in both mitochondria and chloroplasts. The first structure of PreP from Arabidopsis thaliana refined at 2.1 Angstroms resolution shows how the 995-residue polypeptide forms a unique proteolytic chamber of more than 10,000 Angstroms(3) in which the active site resides. Although there is no visible opening to the chamber, a peptide is bound to the active site. The closed conformation places previously unidentified residues from the C-terminal domain at the active site, separated by almost 800 residues in sequence to active site residues located in the N-terminal domain. Based on the structure, a novel mechanism for proteolysis is proposed involving hinge-bending motions that cause the protease to open and close in response to substrate binding. In support of this model, cysteine double mutants designed to keep the chamber covalently locked show no activity under oxidizing conditions. The manner in which substrates are processed inside the chamber is reminiscent of the proteasome; therefore, we refer to this protein as a peptidasome.

Amino Acid Sequence↗
PubMed1999

Subclassifying atypical squamous cells in Thin-Prep cervical cytology correlates with detection of high-risk human papillomavirus DNA.

Recent studies have proposed subclassifying ASCUS into "favor reactive" (ASFR), "not otherwise specified" (ASNOS), and "favor squamous intraepithelial lesion (SIL)" (ASFS). This study explored the reproducibility of these diagnoses with Thin-Prep cytology and their association with high-risk human papillomavirus DNA (HRHPV). Three pathologists and 1 cytotechnologist with 2 to 25 years of experience reviewed 144 Thin-Prep (Cytyc, Boxborough, MA) specimens previously diagnosed as normal, ASFR, ASNOS, ASFS, and SIL. Interobserver reproducibility was computed with the kappa statistic. The original laboratory diagnosis was compared with the presence of HRHPV types. Interobserver reproducibility for a normal or SIL diagnosis was very good (kappa = .68 and .63). Reproducibility for ASFR, ASNOS, and ASFS ranged from poor to fair (kappa = .21, .19, and .32). In a weighted analysis, kappa values for ASFR/ASNOS and ASFS/SIL were .36 and .62, respectively. HRHPV-positivity for preparations originally diagnosed as N, ASFR, ASNOS, ASFS, and SIL were 5.7%, 8.8%, 17.4%, 47.8%, and 54.5%, respectively. The difference in index of HRHPV for either N or ASFR and ASFS or SIL was significant (P < .001). Reproducibility for ASCUS is generally poor, but better reproducibility is obtained by combining ASFS with SIL and, to a lesser degree, ASNOS with ASFR. ASFS and SIL confer a similar index of HRHPV and merit similar management. ASFR may be managed with cytologic follow-up; but this may depend upon the individual laboratory. HPV testing, in conjunction with cytologic and biopsy follow-up, appears useful for estimating the significance of ASCUS subgroups in laboratory practice.

DNA, Viral↗
PubMed1996

Root-end cavity preparation using the MicroMega Sonic Retro-prep Tip. SEM analysis.

The objective of this laboratory study was to compare root-end cavities prepared with sonic Retro-prep tips in a MM1500 Sonic Air handpiece with those created by burs in a conventional handpiece. A total of 80 single-rooted extracted human teeth with mature apices and straight canals were included in the study. Four groups of 20 extracted teeth were prepared as follows: I, a 3-4 mm root-end resection perpendicular to the long axis of the root, with a size 40 sonic Retro-prep tip creating an apical cavity 3 mm into root canal system; II, a 45 degrees bevel of the root-face removing a 3-4 mm root segment and root-end preparation as per group I; III, root-end resection as per group I, with an apical cavity prepared using a size 010 inverted cone bur 3 mm down the long axis of the root; IV, resection as per group II, followed by an apical cavity preparation with a size 010 inverted cone bur 3 mm into the root canal system. The apical root portion and root-end cavities were replicated and prepared for SEM analysis at x 20 and x 80 magnification. The degree of chipping associated with the margin of the root-end cavities, as evaluated with a standard grading system, and the incidence of root-face cracks were noted. Marginal chipping of root-end cavities prepared using sonic instrumentation was significantly worse than that produced by burs (P < 0.001). Perpendicular root-end resections showed significantly better scores than bevelled root-end resections (P < 0.005). The incidence of root-face cracking was low with no significant difference between the experimental groups.

Dental Instruments↗
PubMed1999

In vitro antibacterial effect of RC-Prep components on Streptococcus sobrinus.

The aim of this study was to examine the bacteriostatic and bactericidal effects of the components of RC-Prep: EDTA, urea peroxide and glycol. The minimal inhibitory concentration and the minimal bactericidic concentration of EDTA, urea peroxide and glycol were tested on the viability of Streptococcus sobrinus (S. sobrinus). The combined antibacterial effect of these components was also examined on S. sobrinus. The minimal inhibitory concentration of EDTA was found to be 0.125%, of urea peroxide 0.25%, and of glycol 30%. The minimal bactericidic concentration of EDTA was 0.25%, of urea peroxide 0.5% and of glycol 50%. An antibacterial synergistic effect was found between specific combinations of urea peroxide, EDTA and glycol. No antagonistic effects were found in the various combinations between the components. The antimicrobial effect of the components of RC-Prep was enhanced in specific combinations of the ingredients. This effect might contribute to the intracanal cleansing properties of this medication.

Anti-Infective Agents, Local↗
PubMed1993

Rapid Mini-Prep Isolation of High-Quality Plasmid DNA from Lactococcus and Lactobacillus spp.

A simple, rapid plasmid mini-prep procedure for lactococci and lactobacilli which gives high yields and can be performed on overnight broth cultures is presented. Large plasmids were isolated from both lactococci and lactobacilli, including a 70-kb plasmid from Lactobacillus acidophilus C7. The purity of the resulting plasmid DNA makes it suitable for subsequent molecular manipulations. The convenience of the technique makes this rapid mini-prep procedure suitable for routine plasmid isolation from lactic acid bacteria.

Journal Article↗
PubMed1992

Acrosin profiles of human spermatozoa recovered from the new Sperm Prep II filtration column.

Twenty semen samples were collected and two aliquots of 1.5 ml were prepared from each sample. One sample of each pair (fraction-one) was used for evaluation of semen parameters and total acrosin activity of spermatozoa. The other sample of each pair (fraction-two) was mixed with an equal volume of Ham's F-10 medium and filtered through the Sperm Prep II. At the end of the filtration, the filtrate was pooled, sperm parameters were evaluated and total acrosin activity was assessed. Percentage of normal spermatozoa, sperm motility, and total acrosin activity of spermatozoa were significantly higher in the postfiltered fraction-two than in the fresh fraction-one. Considering the great importance of acrosin for fertilization, it is suggested that Sperm Prep II filtration method may be beneficial in preparing spermatozoa from infertile men with low acrosin profiles for assisted reproduction programs. Further studies will be necessary, however, in order to confirm this, since the present study concerned men with known fertility.

Acrosin↗
PubMed2001

PREP: present requirements for nurses and future possibilities.

All nurses know the requirements for PREP, with its practice, continuing professional development and re-registration standards. However, the system relies on nurses' honesty in completing their PREP record and does not assess a person's fitness to practice as a nurse. Would a system such as the medical re-accreditation process be more appropriate?

Accreditation↗
PubMed1995

Cytologic diagnosis of anal intraepithelial neoplasia using smears and cytyc thin-preps.

To investigate the optimal cytologic method for detecting anal intraepithelial neoplasia, the quality and diagnostic findings in 117 conventionally prepared smears and 191 CYTYC Thin-Preps were compared. Samples were obtained with a dacron swab from subjects participating in a longitudinal study of gay or bisexual men known as the Study to Help the AIDS Research Effort (SHARE). The smear takers were general clinicians who had no experience in obtaining cytologic specimens from the anus. Smears were entirely satisfactory in 48 (41.0%) subjects, limited for interpretation in 41 (35.0%), and unsatisfactory in 28 (23.9%). CYTYC preparations were satisfactory in 158 (82.7%) cases and unsatisfactory in 33 (17.3%). Insufficient cellularity was the most frequent reason for both unsatisfactory smears and CYTYC preparations, but air drying artifact was present in nearly every smear. Squamous intraepithelial lesions (SILs) were detected in four (4.5%) smears compared to 53 (33.6%) CYTYC slides. The detection of SIL correlated with the presence of glandular and metaplastic cells in CYTYC preparations, but this association disappeared if only satisfactory specimens were considered. In conclusion, CYTYC Thin-Preps were satisfactory twice as often as conventional smears (P < 0.005) and detected nearly eight times as many SILs (P < 0.005).

Anus Neoplasms↗
PubMed1994

ScreenMax plasmid mini-prep: super rapid plasmid DNA extraction method.

An ultra-quick method for plasmid DNA extraction using the ScreenMax Plasmid Mini-prep Kit was optimized. Since the method has fewer steps than current methods, the entire process takes only 12 min for two sets of plasmid DNA extractions. DNA quality was excellent for further analyses, including DNA sequencing. The kit's new medium, MMB, provided 5 times the viable cell count and 7 times the dry cell weight compared with the conventional LB medium. The yield of plasmid DNA was 5 times better than from LB medium. From 200 microL of culture, the maximum yield was 7.5 micrograms. The ScreenMax Plasmid Mini-Prep is not only simple and economical but also safe because of its mild reagents. This new procedure is both reliable and reproducible.

DNA↗