Inheritance of superoxide dismutase ( Sod-1) in a perennial x annual ryegrass cross and its allelic distribution among cultivars

Identifying annual ryegrass contamination in perennial ryegrass seed lots has been of major interest in seed-testing laboratories and for seed regulatory agencies in the USA for many years. This study was conducted to characterize a superoxide dismutase locus ( Sod-1) and determine its potential to distinguish cultivated ryegrass species. The inheritance of Sod-1 was evaluated in a three-generation annual x perennial ryegrass mapping population and segregation fitted an expected 1:2:1 ratio for a single locus with two alleles. The molecular form of the Sod-1 locus was determined by H(2)O(2) and KCN inhibitor assays which indicated that the Sod-1, and a second independently segregating Sod-2, locus were both Cu/ZnSod enzymes. The common alleles at the Sod-1 locus were scored in 13 annual and 24 perennial ryegrass cultivars to determine the potential of using this locus for species separation. The Sod-1b allele was homozygous in 98% of perennial ryegrass individuals from 24 cultivars, but those not 100% homozygous for Sod-1b were seed lots with unknown contamination from annual ryegrass. These results indicate that the Sod-1b allele in the homozygous condition is a good indicator of perenniality. All eight annual ryegrass cultivars originating in Europe or Asia had a low frequency of Sod-1b homozygous individuals or none at all. The five cultivars originating in the Western Hemisphere, however, had genotype frequencies for homozygous Sod-1b of up to 56%. The potential of the Sod-1 locus to serve as a test to separate the two growth forms depends on the source of the annual-type contamination.

Novel piperidine .sigma. receptor ligands as potential antipsychotic drugs

sigma receptor ligands represent a new class of potential antipsychotic drugs. This paper presents the structure-activity relationships leading to novel disubstituted piperidine sigma ligands, which have little or no affinity for dopamine D2 receptors. Selectivity for sigma sites over dopamine D2 or serotonin 5-HT2 receptors appears to be governed by the chemical nature of the piperidine nitrogen substituent, its distance from the basic nitrogen, and its orientation relative to the other piperidine substituent. Several of these compounds have good oral potency in some animal models used to evaluate potential antipsychotic drugs. The N-cyclopropylmethyl ketones and ethers (e.g. 6i (DuP 734), 6q, 18a, and 18n) have the best in vivo potency. Compounds 6i (DuP 734) and 6q did not cause catalepsy in the rat, even at very high doses. On the basis of the pharmacology profiles of these sigma ligands, we propose these compounds may be effective antipsychotic drugs, which do not induce extrapyramidal side effects or tardive dyskinesia.

The diaphragm with and without spermicide for contraception: a Cochrane review

BACKGROUND

The diaphragm is usually used with a spermicide. However, some practitioners have suggested that spermicides offer no additional contraceptive protection and have advocated alternative guidelines for the use of diaphragms. The objective of this review was to compare the effectiveness, safety and acceptability of the diaphragm with and without spermicide.

METHODS AND RESULTS

We searched Medline, Embase, Popline, CINAHL, the Cochrane Controlled Trials Register and reference lists of relevant articles. In addition, we contacted experts in the field to identify unpublished studies. Randomized controlled trials comparing women of reproductive age using the diaphragm with and without spermicide as the sole contraceptive method that reported clinical outcomes were selected. Two reviewers independently extracted data on outcomes and trial characteristics and any discrepancies were resolved by consensus or by consultation with the third reviewer. The results of the one identified study are presented descriptively. We identified only one study. No significant difference was found in the pregnancy rates (with typical use or consistent use) or discontinuation rates between the diaphragm-with-spermicide and diaphragm-without-spermicide groups. There was a trend towards higher pregnancy rates in the diaphragm-without-spermicide group. However, this study failed to recruit the planned number of participants and was consequently underpowered.

CONCLUSIONS

As only one underpowered study was identified, we cannot distinguish between the contraceptive effectiveness of the diaphragm with and without spermicide. We cannot draw any conclusion at this point; further research is needed.

Packed red cell transfusion does not compromise chromosome analysis in newborns

PURPOSE

Critically ill neonates are frequently transfused with packed red cells. Some of these transfused neonates also need chromosome analysis. There is a long-standing tradition in pediatrics of not performing chromosome analysis after transfusion. We wished to determine whether transfusion with packed red cells affect the cytogenetic results in neonates.

METHOD

The medical records of all neonates at the Medical College of Georgia who had had chromosome analysis between June 1995 and June 1998 were reviewed. Ten neonates had received transfusion prior to cytogenetic testing. Of these 10 infants, two had been transfused two or more times. Routine cytogenetic analysis of 20 metaphases at 550-band level had been performed on all 10 patients. Heteromorphic markers were compared in 10 randomly selected metaphases for any discrepancy. To determine whether there were theoretical reasons to delay chromosome analysis in transfused neonates, samples of irradiated, and/or filtered, and nonfiltered blood were obtained from the blood bank and analyzed for the presence of lymphocytes.

RESULTS

Prior transfusion did not affect karyotype results. A nonmosaic abnormal karyotype was found in 3 of the 10 patients. A fourth patient's karyotype was 45,X/47,XXX. This mosaicism was constitutive and consistent as demonstrated by a follow-up chromosome analysis. All other abnormal karyotypes were consistent with the dysmorphic phenotype. Randomly selected metaphases did not show any differences in the identifiable heteromorphic markers in all 10 patients. Although there was a 50% chance of patients receiving blood from a donor of opposite sex, there were no instances in which cells with a karyotype of the opposite sex were found in the patients' blood. The irradiated and filtered cultured donor blood samples did not show any metaphases. However, metaphases were seen in the cultures from nonfiltered and nonirradiated donor blood.

CONCLUSIONS

Based on these results one does not need to delay karyotyping babies who have had blood transfusions. Packed red cell transfusion in newborns does not compromise the accuracy of chromosome analysis in our study even with multiple transfusions.

Probabilistic linkage of computerized ambulance and inpatient hospital discharge records: a potential tool for evaluation of emergency medical services

STUDY OBJECTIVES

Emergency medical services (EMS) is an important part of the health care system. The effect of EMS on morbidity, mortality, and costs of illness is difficult to evaluate because hospital information is not available in out-of-hospital databases. We used probabilistic linkage to create such a database from ambulance and inpatient data and demonstrate the potential for linkage to facilitate evaluation of EMS responses resulting in hospital admission.

METHODS

Statewide ambulance and inpatient hospital discharge records were available for 1994 through 1996. Ambulance records indicating admission to the emergency department or hospital (165,649 records) were linked to inpatient hospital records indicating emergency admission (146,292 records) by using probabilistic linkage. Out-of-hospital data (dispatch code, treatments rendered, and ages), linkage rates, and inpatient data (discharge status, charges, length of stay, and payer category) were analyzed.

RESULTS

We linked 24,299 (14.7%) ambulance events to inpatient hospital discharges. If we had used exact linkage methods, we would have only linked 14,621 record pairs, a loss of nearly 40%. Linkage rates were relatively constant between years (approximately 15%) but differed by ambulance dispatch codes. Out-of-hospital dispatch codes with high linkage rates included breathing problems (22.6%), chest pain (21.5%), diabetic problems (16.9%), drowning incidents (14.9%), falls (19.2%), strokes (32.8%), and unconsciousness or fainting episodes (16.1%). Linkage to the hospital record provided access to hospital outcome data. Inpatient mortality was 6.8%. Survivors were discharged home (60.7%), transferred to other acute-care facilities (3.6%) or intermediate-care facilities (23.3%), or discharged with home health care provision (4.9%). The median length of stay was 3 days, and median charges were $6,620; total inpatient charges were $286,737,067.

CONCLUSION

Probabilistic linkage enables ambulance and hospital discharge records to be linked together and potentially increases our ability to critically evaluate EMS by providing access to hospital-based outcomes. Such evaluation will be further improved by linking to ED, other outpatient, and other public health data sources.

A map of human genome sequence variation containing 1.42 million single nucleotide polymorphisms

We describe a map of 1.42 million single nucleotide polymorphisms (SNPs) distributed throughout the human genome, providing an average density on available sequence of one SNP every 1.9 kilobases. These SNPs were primarily discovered by two projects: The SNP Consortium and the analysis of clone overlaps by the International Human Genome Sequencing Consortium. The map integrates all publicly available SNPs with described genes and other genomic features. We estimate that 60,000 SNPs fall within exon (coding and untranslated regions), and 85% of exons are within 5 kb of the nearest SNP. Nucleotide diversity varies greatly across the genome, in a manner broadly consistent with a standard population genetic model of human history. This high-density SNP map provides a public resource for defining haplotype variation across the genome, and should help to identify biomedically important genes for diagnosis and therapy.

Randomized crossover trial comparing the eZ.on plastic condom and a latex condom

This randomized crossover trial compared the breakage and slippage rates, safety, and acceptability of the recently developed polyurethane bi-directional eZ.on condom with a marketed latex condom. Three hundred sixty couples were asked to use 4 eZ.on condoms and 4 latex condoms. Like several other non-latex condoms tested to date, the eZ.on condom had a higher clinical breakage rate than its latex comparator, while the slippage rates were similar. The clinical breakage rate for the eZ.on condom was 5.6%, compared with 0.9% for the latex condom (difference = 4.76%, with upper 95% confidence bound on the difference = 6.26%). Thus, based on an a priori definition of a 2% clinically acceptable difference, the study failed to conclude equivalence relative to clinical breakage. The complete slippage rate for eZ.on was 1.6%; compared to 0.7% for latex (difference = 0.87%, with upper 95% confidence bound = 1.55%). Thus, based on an a priori definition of a 2% difference we concluded equivalence relative to complete slippage. The safety profile of the eZ.on condom was good and similar to the latex condom. The eZ.on was also found to be easier to don and remove than the latex condom. Although no overall preference existed for either condom, nearly 30%women and men strongly preferred the eZ.on condom to the latex condom. The eZ.on condom may be an acceptable alternative for couples unable or unwilling to use latex condoms.

The World Trade Center attack. The paramedic response: an insider's view

The World Trade Center attack and collapse is the first time an aircraft has been used as a weapon of mass effect. The scale and magnitude of this manmade disaster can only be compared with a natural catastrophe such as the Armenian earthquake of December 1988. The importance of an incident command system and the Simple Triage and Rapid Treatment, and the need for fixed Casualty Collection Points, is explained.

Diaphragm versus diaphragm with spermicides for contraception

BACKGROUND

The diaphragm is usually used with a spermicide. However, some practitioners have suggested that spermicides offer no additional contraceptive protection and have advocated alternative guidelines for the use of diaphragms.

OBJECTIVES

The objective of this review was to compare the effectiveness, safety and acceptability of the diaphragm with and without spermicide.

SEARCH STRATEGY

We searched MEDLINE, EMBASE, POPLINE, CINAHL, the Cochrane Controlled Trials Register, and reference lists of relevant articles. In addition, we contacted experts in the field to identify unpublished studies.

SELECTION CRITERIA

Randomized controlled trials comparing women of reproductive age using the diaphragm with and without spermicide as the sole contraceptive method that reported clinical outcomes.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data on outcomes and trial characteristics and any discrepancies were resolved by consensus or by consultation with the third reviewer. The results of the one identified study are presented descriptively.

MAIN RESULTS

We identified only one study. No significant difference was found in the pregnancy rates (with typical use or consistent use) or discontinuation rates between the diaphragm-with-spermicide and diaphragm-without-spermicide groups. There was a trend towards higher pregnancy rates in the diaphragm-without-spermicide group. However, this study failed to recruit the planned number of participants and was consequently underpowered.

REVIEWER'S CONCLUSIONS

As only one underpowered study was identified, we cannot distinguish between the contraceptive effectiveness of the diaphragm with and without spermicide. We cannot draw any conclusion at this point, further research is needed.

Use of whole blood specimens for routine clinical quantitation of hepatitis C virus RNA does not increase assay sensitivity

The measurement of hepatitis C virus (HCV) RNA levels in the blood has, in the last few years, become a critical component in the therapy of patients with HCV infections. Initially, extraction methods for serum and plasma were used, but a newer method that uses Catrimox-14 as the extraction agent for whole blood has been reported. Because the whole blood extraction method may yield higher virus levels if significant levels of virus are present in the white blood cells (WBC), the method was evaluated for use in our clinical diagnostic laboratory despite its higher reagent costs and more time-consuming methodology. RNA was simultaneously extracted from 39 clinical samples by four different methods: Catrimox-14-Trizol extraction from whole blood, Trizol extraction from whole blood, Trizol extraction from serum, and a commercial serum extraction method, the EZNA total RNA kit. In addition, in an effort to quantitate the amount of HCV RNA virus in the WBC, Trizol extraction from isolated WBC was also performed. Quantitative results for samples from which RNA was extracted by all four methods were essentially the same; the Catrimox-14-Trizol method did not yield increased virus levels. Insignificant levels of virus were found in the WBC. The results did not demonstrate a clinical usefulness for the Catrimox-14-Trizol method.

Characterization of osteoblast-like behavior of cultured bone marrow stromal cells on various polymer surfaces

The creation of novel bone substitutes requires a detailed understanding of the interaction between cells and materials. This study was designed to test certain polymers, specifically poly(caprolactone) (PCL), poly(D,L-lactic-CO-glycolic acid) (PLGA), and combinations of these polymers for their ability to support bone marrow stromal cell proliferation and differentiation. Bone marrow stromal cells were cultured from New Zealand White rabbits and were seeded onto glass slides coated with a thin layer of PCL, PLGA, and combinations of these two polymers in both a 40:60 and a 10:90 ratio. Growth curves were compared. At the end of 2 weeks, the cells were stained for both matrix mineralization and alkaline phosphatase activity. There was no statistically significant difference in growth rate of the cells on any polymer or polymer combination. However, there was a striking difference in Von Kossa staining and alkaline phosphatase staining. Cells on PCL did not show Von Kossa staining or alkaline phosphatase staining. However, in the 40:60 and 10:90 blends, there was both positive Von Kossa and alkaline phosphatase staining. These data indicate that PCL alone may not be a satisfactory material for the creation of a bone substitute. However, it may be used in combination with PLGA for the creation of a bone substitute material.

Using a grid framework to aid constructive thinking

A transitional route to the recording of specialist practice for community nurses was undertaken via portfolio development. A grid system was developed to give a concise framework to follow.

Development of the antinuclear and anticytoplasmic antibody consensus panel by the Association of Medical Laboratory Immunologists

The Association of Medical Laboratory Immunologists (AMLI) have developed a panel of antinuclear and anticytoplasmic antibody consensus sera that can be useful for enzyme immunoassay (EIA), Ouchterlony, and immunofluorescence assay methods. It was developed to assist in the evaluation of newly available EIA methods for the detection of autoantibodies. The panel of sera was evaluated in several clinical laboratories and a large number of laboratories owned by manufacturers of clinical autoantibody testing kits. The majority of sera performed well for the EIAs in both the clinical laboratories and the manufacturers' laboratories, but some samples had discrepant results. A major source of discrepancy is the current inability of the EIA results to be directly compared in a quantitative way as no standardization exists. The evaluation demonstrated lower sensitivity of detection by the Ouchterlony method. The limited evaluation of the sera with immunoblotting and Western blotting did not show good agreement with other methods. Further work must be done to standardize blotting methods prior to their use in routine clinical testing. The sera are now available to vendors and clinical laboratories for use in the detection of SS-A, SS-B, Sm, U1-RNP, Scl-70, Jo-1, double-stranded DNA, and centromere antibodies. The availability of the consensus sera will help evaluate and improve the EIA methods currently being used.

Effect of seating position and restraint use on injuries to children in motor vehicle crashes

OBJECTIVE

To determine the effect of restraint use and seating position on injuries to children in motor vehicle crashes, with stratification by area of impact.

METHODS

Children <15 years old involved in serious automobile crashes in Utah from 1992 through 1996 were identified from statewide motor vehicle crash records. Serious crashes are defined as those resulting in occupant injuries with broken bones or significant bleeding or property damage exceeding $750. Probabilistic methods were used to link these records with hospital records. Analysis used logistic regression controlling for age, restraint use, occupant seating position, and type of crash.

RESULTS

We studied 5751 children and found 53% were rear seat passengers. More than 40% were unrestrained. Sitting in the rear seat offered a significant protective effect (adjusted odds ratio: 1.7; 95% confidence interval: 1.6-2.0), and restraint use enhanced this effect (adjusted odds ratio: 2.7; 95% confidence interval: 2.4-3.1). Mean hospital charges were significantly greater for front seat passengers.

CONCLUSIONS

Rear seat position during a motor vehicle crash provides a significant protective effect, restraint use furthers this effect, and usage rates of restraint devices are low. The rear seat protective effect is in addition to and independent of the protection offered from restraints.

Pre-hospital emergency medical services: a population based study of pediatric utilization

OBJECTIVES

To examine emergency medical services (EMS) usage by children in one state.

METHODS

Dispatch of an EMS vehicle in response to a call in the US is referred to as a "run". Runs for Utah for 1991-92 were linked to corresponding hospital records. Abbreviated injury severity scores (AISs) were assigned using ICDMAP-90 software.

RESULTS

For the two year period there were at least 15 EMS runs per 100 children per year, with incomplete reporting from rural areas. EMS response and scene times were similar for all age groups, but interventions were less frequent for children under 5 years of age. When the principal AIS region of injury was the head, neck, or face, cervical immobilization was less frequent for children less than 5 years of age (54%) than for older children (76%) and immobilization was associated with improved outcome, using the crude measure of lower hospital charges. There was a similar association between splinting of upper extremity fractures and reduced hospital charges. Both associations did not appear to be due to differences in injury severity.

CONCLUSIONS

The majority of EMS use by children is for trauma. Children less than 5 years of age are less likely to have an EMS intervention than older children. Whether the lower frequency of interventions is due to the lack of properly sized equipment on the vehicle, or to other factors, is undetermined.