Treatment efficiency of synthetic urban runoff by low-cost mineral materials under various flow conditions and in the presence of salt: Possibilities and limitations.

Urban runoff belongs to important carriers of pollutants that during infiltration can accumulate in the soil/water environment. One of the protection solutions may be the enhancement of infiltration systems by horizontal permeable treatment zones. The article presents the results of column tests carried out in order to determine (1) the influence of the hydraulic loading rate on the dynamic capacities of selected reactive materials: low-cost mineral materials (zeolite, limestone sand, halloysite) and reference material (activated carbon), and control soils (topsoil and Vistula sand) against Zn, NH4+ and PO43-, and (2) remobilization of contaminants under the influence of salt (NaCl 5 g/L) present in synthetic runoff water. The research has revealed that the most useful for the removal of zinc ions was limestone sand (>4.36 mg/g), of orthophosphates - halloysite (2.29 mg/g on the average), and of ammonium ions - zeolite (2.75 mg/g on the average). The control soils were characterized by low ability to immobilize the contaminants tested. In addition, increase in the hydraulic loading rate of synthetic runoff water reduced the dynamic capacity of materials to a variable degree depending on the material applied and the contamination removed (by 24% for limestone sand-PO43- system to 95% for activated carbon-NH4+ system). The presence of NaCl caused significant leaching of ammonium ions from zeolite and halloysite filter beds (up to 99.3%), and phosphates from the activated carbon filter bed (up to 41.3%). All tracer contaminants tested leached intensively from the Vistula sand filter bed, while only ammonium ions leached from the topsoil filter bed. It seems justified to support the performance of infiltration systems by layers of: limestone sand, to enhance the processes of heavy metal precipitation and ammonium ion volatilization by increasing the pH, and halloysite for the sorption of phosphates.

Relationship Between Distortion Product - Otoacoustic Emissions (DPOAEs) and High-Frequency Acoustic Immittance Measures.

BACKGROUND Pathologies that alter the impedance of the middle ear may consequently modify the DPOAE amplitude. The aim of this study was to correlate information from 2 different clinical procedures assessing middle ear status. Data from DPOAE responses (both DP-Gram and DP I/O functions) were correlated with data from multi-component tympanometry at 1000 Hz. MATERIAL AND METHODS The subjects were divided into a double-peak group (DPG) and a single-peak group (SPG) depending on 1000 Hz tympanogram pattern. Exclusion criteria (described in the Methods section) were applied to both groups and finally only 31 ears were assigned to each group. The subjects were also assessed with traditional tympanometry and behavioral audiometry. RESULTS Compared to the single-peak group, in terms of the 226 Hz tympanometry data, subjects in the DPG group presented: (i) higher values of ear canal volume; (ii) higher peak pressure, and (iii) significantly higher values of acoustic admittance. DPOAE amplitudes were lower in the DPG group only at 6006 Hz, but the difference in amplitude between the DPG and SPG groups decreased as the frequency increased. Statistical differences were observed only at 1001 Hz and a borderline difference at 1501 Hz. In terms of DPOAE I/O functions, significant differences were observed only in 4 of the 50 tested points. CONCLUSIONS The 1000-Hz tympanometric pattern significantly affects the structure of DPOAE responses only at 1001 Hz. In this context, changes in the properties of the middle ear (as detected by the 1000 Hz tympanometry) can be considered as prime candidates for the observed variability in the DP-grams and the DP I/O functions.

Repeatability of transient-evoked otoacoustic emissions in young adults.

BACKGROUND: The aim of this study was to evaluate the repeatability and variability of TEOAE characteristics in hearing screening tests performed under practical conditions on normal subjects. MATERIAL/METHODS: A group of 11 young, normal-hearing subjects aged 19-24 years was tested. They were examined otologically and audiologically prior to the tests and no ear pathologies were found. Responses were acquired with a commercially available instrument (Integrity, Vivosonic Inc.) using a standardized OAE protocol. The TEOAE tests were repeated 3 times in each subject at random intervals within 24 h. The analyzed parameters of interest were: (i) whole wave reproducibility (WWR) and; (ii) signal-to-noise ratio (SNR). RESULTS: WWR and SNR did not differ significantly among the 3 measurement sessions. In most cases the differences in WWR among measurements were around 1-2% and for SNRs they were 1-4 dB SNRs and were highest in the 1-2 kHz range. TEOAE-based tests can be useful tools for hearing screening. CONCLUSIONS: The tests can give reliable results provided that adequate procedures are used and low-noise conditions are ensured. The tests are best complemented with other examinations to widen the range of ear pathologies able to be detected.

Pregabalin and dexamethasone in combination with paracetamol for postoperative pain control after abdominal hysterectomy. A randomized clinical trial.

BACKGROUND: Multimodal analgesia may be important for optimal postoperative pain treatment and facilitation of early mobilization and recovery. We investigated the analgesic effect of pregabalin and dexamethasone in combination with paracetamol after abdominal hysterectomy. METHODS: One hundred and sixteen patients were randomly assigned to either group A (paracetamol+placebo x 2), group B (paracetamol+pregabalin+placebo) or group C (paracetamol+pregabalin+dexamethasone). According to randomization and preoperatively, patients received paracetamol 1000 mg, pregabalin 300 mg, dexamethasone 8 mg or placebo. General anaesthesia was performed. Postoperative pain treatment was paracetamol 1000 mg x 4 and patient-controlled intravenous morphine, 2.5 mg bolus. Nausea was treated with ondansetron. Morphine consumption, pain score (visual analogue scale) at rest and during mobilization, nausea, sedation, dizziness, number of vomits and consumption of ondansetron were recorded 2, 4 and 24 h after the operation. P<0.05 was considered statistically significant. RESULTS: The 24-h morphine consumption and pain score, both at rest and during mobilization, were not significantly different between treatment groups. The mean nausea score (P=0.002) was reduced in group C vs. A. The number of vomits was significantly reduced in both group B (P=0.041) and C (P=0.001) vs. A. Consumption of ondansetron was reduced in group C vs. A and B (P<0.001). Other side effects were not different between groups. CONCLUSION: Combinations of paracetamol and pregabalin, or paracetamol, pregabalin and dexamethasone did not reduce morphine consumption and pain score compared with paracetamol alone for patients undergoing abdominal hysterectomy. Dexamethasone reduced nausea, vomiting and use of ondansetron.

Lambda as a cloning vector.

Advantages of lambda as a cloning vector are discussed along with considerations for the insert DNA (i.e., size, spi and hfl state). Maps of lambda-derived cloning vectors are provided in addition to a discussion and map of a cosmid (a lambda-derived plasmid vector).

Plating lambda phage to generate plaques.

This unit provides detailed protocols for isolating a single plaque by titering serial dilutions or streaking on a lawn of cells. A discussion of phage transfection and in vitro packaging is also included.

Growing lambda-derived vectors.

It is often necessary to grow large quantities of lambda-derived vectors, so that DNA can be made from them. This unit describes a procedure for making a phage stock by plate lysis, and an Alternate Protocol gives details on how to make a liquid lysate. Storage of phage lysates is described in a Support Protocol.

Preparing lambda DNA from phage lysates.

DNA extracted from lambda-derived vectors is typically subcloned into plasmid or filamentous phage vectors. The first two protocols describe methods for isolating phage DNA from large- and medium-scale liquid lysates. These two methods use either density-gradient centrifugation or ion-exchange chromatography to purify the phage particles. The third protocol describes a rapid procedure for isolating phage DNA, suitable for small-scale liquid lysates.

Introduction to lambda phages.

The biology of lambda-derived vectors is extremely well understood. This introduction to the biology of lambda and related phages is included to help readers use the lambda vectors that are employed in the manual and to help readers understand new lambda vectors that are being developed. Specific topics include a discussion of lytic growth (i.e., requirements for DNA replication, packaging and lysis) and lysogenic growth (i.e., requirements for lysogenization and induction of a lysogen).

Techniques for bacterial cell culture: media preparation and bacteriological tools.

Basic information for the culture of bacteria is presented in this appendix, using Escherichia coli as a representative organism. The techniques and recipes should be readily transferrable. Specifics are given for liquid and solid media, rich and minimal media, stab agar, as well as a description of the tools required to inoculate and culture bacteria.

Growing bacteria in liquid media.

The procedure for inoculating overnight (starter) cultures of E. coli from a single colony is described along with considerations for growing larger cultures. Also included are two methods for monitoring cell growth using a spectrophotometer or a hemacytometer.

Growing bacteria on solid media.

Detailed protocols are provided for titering and isolating bacterial colonies by serial dilutions, or alternatively by streaking or spreading a plate. Support protocols describe replica plating as well as methods for storing strains as agar stabs or frozen glycerol stocks.

Experimental model of hepatic venoocclusive disease (VOD) caused by dactinomycin--preliminary report about hepatoprotective effect of amifostine.

UNLABELLED: The purpose of the study was elaboration of the experimental model of hepatic venoocclusive disease (VOD) induced by dactinomycin and investigation of possible hepatoprotective effects of amifostine and heparin individually or in combination with dexamethasone. 198 Wistar strain male rats were used in the trial in two series of experiments. In the first series the experimental model of VOD induced by dactinomycin was elaborated on the group of 18 animals (divided into 3 groups receiving intraperitoneally isotonic salt solution, dactinomycin or nitrosamine). Nitrosamine--a well-known agent causing VOD--was used as positive control. Open biopsies of the liver and blood collections were repeated in order to determine liver enzymes' concentrations. Histopathological examinations demonstrated that dactinomycin caused liver lesion corresponding with VOD picture. Second series of animals was divided into 6 groups receiving the following drugs: I--0.9% NaCl solution, II--dactinomycin (ACT), III--ACT + fraxiparine s.c., IV--ACT + fraxiparine + dexamethasone, V--ACT + amifostine. Five animals from each group were sacrificed on the 3rd and 7th day after each cycle of drug administration. Blood was drawn in order to determine the following: AspAT, AlAT, Falk, GGTP and LDH. Intravital wedge biopsies under anesthesia with the use of inactin were also performed. Liver samples were stained with the use of H&E, p. a. S and Gomory's techniques. We did not find significant differences in liver enzymes' levels between the groups. Pathological changes corresponding with VOD picture of different intensification were found in liver samples from all the rats receiving ACT. Changes became more and more intensive after consecutive cycles. Lesion of central veins' and liver sinusoids' endothelium dominated. Fraxiparine administered individually or in combination with dexamethasone did not prevent the lesion. Administration of amifostine before ACT decreased pathomorphological changes in liver. Dactinomycin caused homogenous subclinical liver lesion corresponding with VOD. It may also occur in children receiving ACT in the course of nephroblastoma's treatment. But probably the changes are too subtle to manifest themselves clinically with exception of patients particularly sensitive (for example after previous radiotherapy). Lack of differences observed in liver enzymes' levels between the groups supports the explanation. Markers of lesion of liver vessels' endothelium should be looked for to make more specific diagnostics of VOD possible. Hepatoprotective properties of amifostine need further studies. CONCLUSIONS: 1. It is possible to create the experimental model of VOD induced by dactinomycin administration. 2. Amifostine seems to act hepatoprotectively to liver lesions caused by dactinomycin.

Grading of severity of postdural puncture headache after 27-gauge Quincke and Whitacre needles.

BACKGROUND: Small-gauge needles are reported to have a low incidence of complications. Pencil-point needles are associated with a lower frequency of postdural puncture headache (PDPH), but a higher failure rate than Quincke needles. METHODS: The incidence of PDPH was investigated in 200 patients under the age of 45, undergoing day-care surgery, after spinal anaesthesia with either 27-gauge Quincke or Whitacre needle. The severity of headache was graded as I (mild), II (moderate) or III (severe) using a grading system based on the visual analogue scale (VAS) associated with a functional rating (FG). RESULTS: The frequency of PDPH following the Whitacre needle was 0% and 5.6% after the Quincke needle (P = 0.05). Two PDPHs were assessed as grade III, and three as grade II. All PDPHs occurred when the Quincke needle bevel was withdrawn perpendicular to the dural fibres following parallel insertion. No PDPH occurred when the bevel was inserted and removed parallel to the dural fibres (P < 0.05). There was no statistical difference (P > 0.08) in the incidence of PDPH and postdural puncture-related headaches (PDPR-H) in patients with recurrent headaches or migraine compared to patients with no previous history of headaches. CONCLUSIONS: We conclude that the 27-gauge Whitacre needle is the 'needle of choice' in patients with normal body stature. The incidence of PDPH following Quincke needles may not only be affected by the direction of the bevel during insertion but also during removal. Statistically, there was no gender variation in PDPH in this study (P = 0.5). A previous history of recurrent headache or migraine does not predispose to PDPH.

DNA-bound Fos proteins activate transcription in yeast.

We constructed genes encoding the DNA binding region of the bacterial LexA repressor fused to the v-fos and c-fos oncogene products. The resulting LexA-Fos fusion proteins activated transcription in yeast. Transcription activation by these proteins was as strong as transcription activation by proteins native to yeast. LexA-Fos fusion proteins only activated transcription of genes when they were bound to LexA binding sites inserted upstream of those genes. Transcription was activated less strongly by similar proteins in which the DNA binding region of LexA was fused to vMyc and cMyc. Transcription was not activated by native LexA or by proteins containing the DNA binding domain of LexA fused to bacteriophage 434 repressor or yeast MAT alpha 2 protein. These results demonstrate that Fos proteins activate eukaryotic gene expression when they are bound to promoter DNA, and thus suggest that Fos proteins exert some of their effects because they stimulate transcription of cellular genes. Regulation of transcription by Fos and Myc proteins in yeast provides a phenotype that may facilitate genetic analysis of the function of these proteins in higher organisms.

New gene in Escherichia coli K-12 (drpA): does its product play a role in RNA synthesis?

The mutation drpA1 defines a new gene in Escherichia coli K-12 that maps at about 5.2 min. This mutation was obtained after enriching a population of cells for temperature sensitive dna mutations with the [3H]thymidine "suicide" technique followed by screening for mutants defective in transposon Tn5 precise excision. When growing cells carrying the drpA1 allele were shifted to the nonpermissive temperature, we showed that DNA, RNA, and protein syntheses shut off quickly, with the cessation of RNA synthesis occurring first. A recombinant plasmid between pBR322 and an HindIII fragment from wild-type E. coli restores the growth defect in drpA1 mutants. Using transposon Tn5 mutagenesis of this plasmid, we have been able to correlate the presence of a 68-kilodalton protein, as observed with the maxicell technique, with the ability of this plasmid to restore growth to drpA1 mutants.