Outcomes associated with cesarean section versus vaginal breech delivery at a university hospital.

OBJECTIVE: To determine whether vaginal breech delivery is associated with increased morbidity in term breech singletons using strict selection criteria. This study encompasses our previous studies (in 1987 and 1995) and extends our experience to 21 years. STUDY DESIGN: Retrospective cohort study from 1980 to 2001 including term, non-anomalous singleton breech deliveries selected by strict criteria. Univariable and multivariable analyses were performed for neonatal and maternal outcomes. RESULTS: Five hundred and eleven women underwent cesarean section and 214 a trial of labor. We found greater overall maternal morbidity in the cesarean section group (odds ratio (OR) 1.89, 95% confidence interval (CI)=1.34-2.65). In the vaginal delivery group, neonates were more likely to have had >1 day of mechanical ventilation (OR 10.0, 95% CI=1.56-63.9). No maternal deaths occurred and no neonatal deaths or seizures occurred. CONCLUSION: Given our findings, offering a trial of vaginal breech delivery to well-counseled strictly selected patients remains an appropriate option.

Further characterization of HLA homozygous typing cell lines at the LMP2 polymorphic codon 60 by an ARMS typing method.

LMP2 is a subunit of the 20S proteasome within the cellular cytosolic compartment that is thought to cleave proteins into approximately 9 amino acid long oligopeptides. It is hypothesized that changes in the low molecular mass protease (LMP) gene sequence may alter the activity or specificity in which the LMP genes cleave peptides. Currently, the typing method for LMP2 involves polymerase chain reaction (PCR), restriction enzyme digestion, and gel electrophoresis. To help reduce the cost and cumbersomeness of this method, a new typing method was adapted for the LMP2 gene. To establish this new amplification refractory mutation system (ARMS) typing method, primers have been defined, amplification conditions optimized, and control cell lines sequenced to validate testing parameters. Results are listed for selected 10th and 11th International Histocompatibility Workshop homozygous cell lines.

The effects of a 0.12% chlorhexidine-digluconate-containing mouthrinse versus a placebo on plaque and gingival inflammation over a 3-month period. A multicentre study carried out in general dental practices.

Several previous studies have evaluated the effects of 0.12% chlorhexidine digluconate (ChD) mouthrinses on plaque and gingival inflammation. However, previously, none have been based in general dental practices. The aim of this study was to evaluate the potential to conduct controlled periodontal clinical trials in co-operation with general dental practitioners (gdps). The project took place in 5 general dental practices in the South of England. 121 healthy subjects (24 at 4 sites and 25 at the 5th), aged 18-65 years, mean 35 +/- 12) years participated in a double-blind, randomised study during which they received full mouth assessments for plaque and gingival bleeding at baseline, 6 and 12 weeks. 60 subjects were randomly assigned to use the 0.12% ChD mouthwash and 61 the placebo. The assessments were carried out by 5 gpds, who had previously achieved inter-examiner kappa scores of 0.78-0.85 (mean 0.81) for the plaque index (PII), and of 0.73-0.94 (mean 0.87) for a modified gingival index (mGI), and who maintained kappa scores of 0.51-0.90 for PII and of 0.73-1.00 for mGI during the 12 months required to complete the study. 98 subjects (48 ChD and 50 placebo) completed the study. Even though the baseline levels of plaque and gingivitis were low, by week 12, mean whole mouth plaque score of the ChD mouthwash users had fallen from 1.33 at baseline to 0.96 and was significantly lower (p < 0.001) than for the placebo users, 1.31 at baseline to 1.13. Whole-mouth gingival bleeding score fell from 0.56 to 0.42 in the ChD mouthwash group but was unchanged (0.54-0.55) in the placebo group. A subsidiary data analysis which considered the effects at sites indicated that within these overall differences, the ChD users experienced almost 2 x the reduction from plaque score 2 at baseline at proximal molar sites over a 12-week period (50.6% ChD versus 27.6% placebo). It was concluded that 0.12% ChD mouthwash reduced plaque accumulation by 28% and gingival inflammation by 25% over a 12-week period, that it is feasible for a group of gdps to maintain high levels of inter-examiner consistency in the use of PII and mGI, that it is also feasible to carry out such a multicentre study in general dental practice, and that the use of mean mouth scores per subject to analyse the effects of mouthrinses may well mask variations in response throughout the mouth.

Research in general dental practice--what is involved? Part 2. Specific considerations.

In the previous paper (Part 1. General Considerations), the problems which GDPs are likely to encounter when they embark on research were explored and an outline of the structure a GDP might use when planning to undertake a research project outlined. This paper explains how a recent mouthrinse study, carried out by five GDPs in five different practices, was planned and executed and how the principles described in the first paper were applied.

Research in general dental practice--what is involved? Part 1. General considerations.

This paper examines the problems encountered by general dental practitioners (GDPs) when they attempt to carry out research. It outlines the possible stages a GDP might use when planning to undertake research and possible areas of interest to investigate. Part 2 will appear in a subsequent issue of Primary Dental Care.

Conditioned taste aversions induced by alcohol and lithium in rats selectively bred for ethanol neurosensitivity.

Rats that were selectively bred for differences in alcohol-induced sleep time (alcohol neurosensitivity) were tested for differences in formation and extinction of alcohol- and LiCl-induced conditioned taste aversions. Male rats bred for high, control, or low alcohol sensitivity (HAS, CAS, and LAS rats, respectively) were deprived of water and given daily 30 min access to water for a baseline period of 7 days. Rats were then given a novel 0.125% sodium saccharin solution, followed by an intraperitoneal injection of either saline, 2 g/kg of ethanol (at 10% w/v), or 50.9 mg/kg of LiCl (0.15 M) on 3 conditioning days. Each saccharin exposure was followed by a recovery day of access to water. The ethanol-induced saccharin aversion extinguished more rapidly in LAS rats than in CAS or HAS rats (p < 0.05), but LiCl conditioned equivalent aversions in each group. Also, ethanol injection results in large differences in observed resting behavior in these rats (HAS > CAS > LAS), but LiCl injection produced no reliable group differences in resting. The weaker alcohol-induced taste aversion in LAS rats accords with their previously measured higher oral consumption of alcohol (Kulkosky et al., Alcoholism 17:545-551, 1993) and the idea that alcohol intake is limited by an expectancy of postingestive consequences. The weaker ethanol-induced aversion in LAS rats reflects selective breeding of an alcohol-specific trait and not a general difference in aversive conditioning or chemical neurosensitivity.