Scandcleft randomized trials of primary surgery for unilateral cleft lip and palate: Speech proficiency at 10 years of age

BACKGROUND & AIM

To assess consonant proficiency and velopharyngeal function in 10-year-old children born with unilateral cleft lip and palate (UCLP) within the Scandcleft project.

METHODS & PROCEDURES

Three parallel group, randomized, clinical trials were undertaken as an international multicentre study by nine cleft teams in five countries. Three different surgical protocols for primary palate repair (Arm B-Lip and soft palate closure at 3-4 months, hard palate closure at 36 months, Arm C-Lip closure at 3-4 months, hard and soft palate closure at 12 months, and Arm D-Lip closure at 3-4 months combined with a single-layer closure of the hard palate using a vomer flap, soft palate closure at 12 months) were tested against a common procedure (Arm A-Lip and soft palate closure at 3-4 months followed by hard palate closure at 12 months) in the total cohort of 431 children born with a non-syndromic UCLP. Speech audio and video recordings of 399 children were available and perceptually analysed. Percentage of consonants correct (PCC) from a naming test, an overall rating of velopharyngeal competence (VPC) (VPC-Rate), and a composite measure (VPC-Sum) were reported.

OUTCOMES & RESULTS

The mean levels of consonant proficiency (PCC score) in the trial arms were 86-92% and between 58% and 83% of the children had VPC (VPC-Sum). Only 50-73% of the participants had a consonant proficiency level with their peers. Girls performed better throughout. Long delay of the hard palate repair (Arm B) indicated lower PCC and simultaneous hard and soft palate closure higher (Arm C). However, the proportion of participants with primary VPC (not including velopharyngeal surgeries) was highest in Arm B (68%) and lowest in Arm C (47%).

CONCLUSIONS & IMPLICATIONS

The speech outcome in terms of PCC and VPC was low across the trials. The different protocols had their pros and cons and there is no obvious evidence to recommend any of the protocols as superior. Aspects other than primary surgical method, such as time after velopharyngeal surgery, surgical experience, hearing level, language difficulties and speech therapy, need to be thoroughly reviewed for a better understanding of what has affected speech outcome at 10 years.

WHAT THIS PAPER ADDS

What is already known on the subject Speech outcomes at 10 years of age in children treated for UCLP are sparse and contradictory. Previous studies have examined speech outcomes and the relationship with surgical intervention in 5-year-olds. What this study adds to the existing knowledge Speech outcomes based on standardized assessment in a large group of 10-year-old children born with UCLP and surgically treated according to different protocols are presented. While speech therapy had been provided, a large proportion of the children across treatment protocols still needed further speech therapy. What are the potential or actual clinical implications of this work? Aspects other than surgery and speech function might add to the understanding of what affects speech outcome. Effective speech therapy should be available for children in addition to primary surgical repair of the cleft and secondary surgeries if needed.

Risk Factors for Operating Room No-Show in an Academic Otolaryngology Practice

OBJECTIVES/HYPOTHESIS

A no-show to the operating room date negatively impacts a hospital and can lead to increased costs for an institution in terms of time, materials, and manpower. Our objectives are to identify the factors associated with operating room no-shows in order to increase clinical efficiency, reduce hospital costs, and increase patient access to care.

STUDY DESIGN

Single institution retrospective chart review.

METHODS

A retrospective review was performed of all surgeries within the Otolaryngology department performed at a single tertiary academic center between 2006 and 2019. Demographic and surgical data were collected from the charts. Descriptive, univariate, and multivariate statistics were performed on the data.

RESULTS

There were a total of 1,752 no-shows and 46,440 patients who did show with an overall no-show rate of 3.63%. A multivariate logistic regression analysis was performed to compare patients who did not show for surgery to those who did. Analysis found multiple risk factors for not showing to surgery that were statistically significant (P < .05) and included decreasing age, planned outpatient case, head and neck oncology subspecialty, increasing distance from the facility, higher number of clinic no-shows, and not having private insurance. African-American race was more likely to show for surgery as scheduled.

CONCLUSIONS

Numerous factors may play a role on whether or not a patient attends a scheduled surgical date. Some of these factors may be preventable or modifiable to mitigate increased hospital costs associated with no-show to surgery and increase access to care.

LEVEL OF EVIDENCE

3 Laryngoscope, 132:1738-1742, 2022.

125 Influence of length of porcine follicle-stimulating hormone (p-FSH) treatment before ovum pickup on ovarian response and invitro embryo production in Holstein heifers

Ovarian follicle stimulation with exogenous FSH before ovum pickup (OPU) in Bos taurus females is a common practice to increase invitro embryo production (IVP). The optimal stimulatory period length for OPU-IVP, however, has not been definitively ascertained. The objective of the present study, therefore, was to determine the effect of length of the superstimulatory treatment period before OPU on ovarian response and IVP in Holstein heifers. Nonpregnant heifers (n=57) 13.8±0.2 months of age with moderate body condition score (3.0±0.1; scale 1 to 5) were assigned in a completely randomised design to one of the following experimental groups: FSH2d: 200mg of p-FSH (Folltropin-V®, Vetoquinol) distributed in four injections (60, 60, 40, and 40mg) of FSH 12h apart; FSH3d: 200mg of p-FSH distributed in six injections (40, 40, 40, 40, 20, and 20mg) of FSH 12h apart. Timing of follicular wave emergence was synchronized by dominant follicle removal 36h before the first p-FSH injection in all heifers. An intravaginal progesterone (P4) implant (1.38g of P4 CIDR®, Zoetis) was inserted at the time of the first p-FSH injection and removed at the time of OPU, which occurred in all heifers at 44h (Nivet et al. 2012 Reproduction 143, 165-171; https://doi.org/10.1530/REP-11-0391) after the last p-FSH injection. Additionally, follicle number was determined at OPU and classified as small (&lt;6mm), medium (6–10mm) or large (&gt;10mm). Oocytes from follicles of different sizes were pooled by heifer at OPU and then classified and subjected to IVP procedures. Differences between treatment groups were evaluated using generalized linear mixed models (SAS 9.4; SAS Institute Inc.) and data are presented as mean±s.e.m. (Table 1). Lengthening the FSH treatment period resulted in a greater (P=0.01) number of large follicles; however, the number of small, medium-size, and total follicles was not different between groups. Number of total recovered oocytes, viable oocytes, cleaved oocytes, as well as recovery rate, percent viable oocytes, and cleavage rate were not different (P&gt;0.2) between groups. Similarly, the number of blastocysts produced per heifer and blastocyst rate were not different (P&gt;0.9) among groups. In conclusion, lengthening the period of FSH treatment by 1 day increased the number of large follicles at OPU but did not improve overall ovarian response, oocyte recovery, or embryo production. Table 1. Ovarian response and IVP of heifers treated with p-FSH during 2 or 3 days before ovum pickup Response FSH2d (n=28) FSH3d (n=29) P-value Small follicles (n) 5.9±0.6 5.7±0.8 0.83 Medium follicles (n) 17.0±2.4 12.9±1.6 0.18 Large follicles (n) 2.5±0.5 4.5±0.6 0.01 Total follicles (n) 25.4±2.6 23.1±1.8 0.60 Total oocytes (n) 17.0±2.5 13.0±1.2 0.23 Recovery rate (%) 62.6±3.7 56.9±3.1 0.26 Viable oocytes (n) 14.4±2.0 11.3±1.1 0.30 Viable oocytes (%) 85.0±2.4 88.0±3.0 0.31 Cleaved oocytes (n) 8.7±1.6 7.1±1.2 0.62 Cleavage rate (%) 54.7±5.7 54.1±5.7 0.96 Blastocysts (n) 3.2±0.6 3.2±0.7 0.98 Blastocyst rate (%) 20.6±4.0 22.4±3.7 0.97

71 Effect of follicle-stimulating hormone dose and circulating progesterone before ovum pickup and invitro embryo production in pregnant Holstein heifers

Superstimulation with exogenous FSH before ovum pickup for invitro embryo production (IVP) improves embryo production. However, there is limited information on different FSH dose regimens and the effect of progesterone (P4) concentrations on IVP. Thus, the objective of the present study was to evaluate the effect of FSH dose and circulating P4 on ovarian superstimulation responses, before ovum pickup (OPU) on IVP in pregnant heifers. Pregnant Holstein heifers (n=47) 19.5±0.3 months of age with moderate body condition score (3.3±0.03; scale 1 to 5) were randomly assigned to 2 treatment groups, p-FSH (Folltropin-V, Vetoquinol) 160mg (FSH160) or p-FSH 300mg (FSH300), in a crossover design. Two sessions of OPU were performed on each animal at 48 and 62 days of gestation, with a washout interval between sessions of 14 days. Dominant follicle removal (DFR) was utilised to synchronize follicular wave emergence, and FSH treatments were initiated 36h later. Heifers in both groups received a total of 4 FSH injections 12h apart as follows: FSH160 (48.0, 42.7, 37.3, and 32.0mg) or FSH300 (90.0, 80.0, 70.0, and 60.0mg). All heifers underwent OPU 40h after the last FSH treatment. Blood samples were collected for P4 quantitation at OPU and number of small (&lt;6mm), medium (6–10mm), and large (&gt;10mm) follicles were determined before OPU. Cumulus–oocyte complexes (COCs) recovered were processed and invitro embryo production was performed using standard procedures. Differences between treatment groups were evaluated using generalized linear mixed models, and data are presented as mean±s.e.m. (Table 1). Heifers treated with 300mg of p-FSH had a greater (P&lt;0.05) number of medium-size follicles, total number of follicles, total COCs recovered, number of viable COCs, and number of blastocysts produced. In addition, heifers treated with 300mg of p-FSH had a greater cleavage rate (P=0.03). Circulating P4 was on average 10.1±0.4ng mL−1 and did not differ between gestation days (P=0.12). Furthermore, circulating P4 did not affect (P&gt;0.10) any of the outcomes evaluated, nor was there an FSH dose by circulating P4 interaction (P&gt;0.05). In conclusion, increasing the dose of p-FSH before OPU from 160 to 300mg resulted in an increase in the total number of follicles, number of oocytes, and number of blastocysts produced in pregnant donors without changes in blastocyst rate, regardless of progesterone concentrations at the time of OPU. Table 1. Ovum pickup and invitro embryo production in pregnant heifers treated with different doses of p-FSH Item FSH160 FSH300 P-value Small follicles (n) 5.0±0.6 3.5±0.4 0.02 Medium follicles (n) 14.4±0.8 18.3±0.9 0.0003 Large follicles (n) 2.9±0.3 2.5±0.3 0.28 Total follicles (n) 22.3±0.7 24.3±0.9 0.04 Total oocytes (n) 12.8±0.7 14.7±1.0 0.02 Recovery rate (%) 56.2±2.1 59.7±2.7 0.20 Viable oocytes (n) 11.4±0.7 13.3±1.0 0.02 Viable oocytes (%) 89.9±1.7 88.0±2.4 0.22 Cleavage rate (%) 63.8±4.3 71.5±3.7 0.03 Cleaved oocytes (n) 7.2±0.7 9.3±0.9 0.14 Blastocysts (n) 2.7±0.4 3.6±0.7 0.02 Blastocyst rate (%) 22.0±3.3 22.4±3.6 0.74

48 Timing of luteolysis and conceptus expulsion after induced pregnancy loss at three different timepoints after maternal recognition of pregnancy in cattle

Results from previous research indicate that induced pregnancy loss (IPL) on Day 36 of gestation in cattle resulted in luteolysis by gestation Day ∼45. The aim of this study was to test the hypothesis that IPL at 25, 35, or 55 days of gestation will result in luteolysis and whether the interval between IPL and luteolysis is positively associated with days of gestation at time of treatment. Pregnant non-lactating beef cows were randomly assigned to undergo IPL, consisting of an intrauterine infusion of 120mL of hypertonic saline (7.2%), at Day 25 (IPL25, n=15), Day 35 (IPL35, n=14), or Day 55 (IPL55, n=14). Corpus luteum (CL) volume and embryo/fetal viability were evaluated by transrectal B-mode ultrasonography daily for 19 days following treatment and every other day subsequently until luteolysis was identified or gestation Day 91. Blood flow through the CL was evaluated using colour-Doppler ultrasonography, and luteolysis was defined as the day when &lt;25% of the CL was represented with colour pixels. Conceptus expulsion was defined as the absence of a conceptus and fluid accumulation in the uterus was &lt;25%. Data were analysed using Proc Mixed in SAS (v9.4; SAS Institute Inc.). Cessation of conceptus heartbeat occurred in all animals within 24h of administration of treatment. Day of luteolysis occurred earlier (P&lt;0.01) in IPL25 (5.3±0.4d) than IPL55 (8.9±1.4d) cows, and luteolysis tended (P=0.07) to occur earlier in IPL35 (6.6±0.6d) than IPL55 cows; however, values for this variable in IPL25 and IPL35 cows were similar (P&gt;0.2). The variance in timing of luteolysis was greater for IPL55 than for IPL35 cows, whereas variance for IPL35 was greater than that for IPL25 (P&lt;0.05) cows. Conceptus expulsion was detected earlier (P&lt;0.01) in IPL25 (Day 4.2±0.4) and IPL35 (Day 5.8±0.5) than IPL55 (Day 10.4±1.4) cows; however, IPL25 and IPL35 cows had similar (P&gt;0.1) values for this variable. Values for luteolysis and conceptus expulsion were correlated in IPL35 (r=0.84; P&lt;0.01) and IPL55 (r=0.88; P&lt;0.01) cows, whereas there was no correlation among values for these variables in IPL25 (r=0.31; P=0.3) cows. There were effects of treatment (P&lt;0.01), time (P&lt;0.01), and treatment by time interaction (P&lt;0.01) on CL volume. Volume of the CL was less (P&lt;0.04) in IPL25-treated cows by treatment day 5 compared with that in IPL55-treated cows. Additionally, CL volume was less (P&lt;0.03) in IPL25 by treatment day 6 than in IPL35 cows, and IPL35 cows had a lesser (P&lt;0.01) CL volume starting on treatment day 10 than IPL55 cows. Induction of pregnancy loss at different times of gestation resulted in luteolysis; however, the interval between treatment and luteolysis tended to increase as gestation days increased. Furthermore, the variability in the timing of luteolysis increased as gestation days increased. Results from the present study support the working hypothesis of presence of a continuous mechanism for CL maintenance during pregnancy beyond the classical maternal recognition period in cattle.

Observation of Silicone Oil Within the Vitreous and Sclera Following Intravitreal Administration of Biotherapeutics Using Insulin Syringes in Cynomolgus Monkeys

Silicone oil droplets have been reported in the eyes of human patients following intravitreous (IVT) injections with several marketed biotherapeutic products. Intravitreous administration of a novel biotherapeutic in a 14-week cynomolgus monkey study using insulin syringes was associated with 2, non-test-article-related phenomena: "vitreous floater/clear sphere" on indirect ophthalmoscopy and intrascleral "foreign material near injection track" on histopathology. Retrospective analysis of 81 other preclinical studies of IVT administration of novel biotherapeutics found a greater frequency of clear spheres in monkey IVT studies using insulin syringes and formulations containing polysorbate. We were able to correlate microscopic findings of clear circular to oval areas in the sclera near the injection track with an energy-dispersive X-ray spectroscopy (EDS) signal for silicon at the same location in the sclera. These observations provide further evidence that silicone lubricant in insulin syringes/needles is the source of clear spheres noted in the vitreous and foreign material noted near the injection track in the sclera. Although considered inert and toxicologically insignificant, silicone deposition within the eye should form part of the risk-benefit equation in a clinical setting.

Buccinator Sandwich Pushback: A New Technique for Treatment of Secondary Velopharyngeal Incompetence

Objective

A small percentage of patients have inadequate velopharyngeal closure, or secondary velopharyngeal incompetence, following primary palatoplasty. Use of the buccinator musculomucosal flap has been described for primary palate repair with lengthening, but its use in secondary palate lengthening for the correction of insufficient velopharyngeal closure has not been described. This study presents the results of a series of patients who had correction of secondary velopharyngeal incompetence using bilateral buccinator musculomucosal flaps used as a sandwich.

Patients

In this prospective study between 1995 and 1998, a group of 16 patients with insufficient velopharyngeal closure as determined by speech assessment and videoradiography were selected. Nasopharyngoscopy was carried out in addition in a number of cases. Case selection was a result of these investigations and clinical examination in which the major factor in velopharyngeal insufficiency was determined to be short palatal length.

Design

The patients underwent palate lengthening using bilateral buccinator musculomucosal flaps as a sandwich. All patients were assessed 6 months postoperatively. The operative technique, postoperative course, and recorded postoperative complications including partial/total flap necrosis and residual velopharyngeal insufficiency were evaluated. Preoperative and postoperative speech samples were rated by an independent speech therapist.

Results

Ninety-three percent (15 of 16) had a significant improvement in velopharyngeal insufficiency, and 14 patients had no hypernasality postoperatively. Both cases of persistent mild hypernasality had had a recognized postoperative complication.

Conclusion

The sandwich pushback technique for the correction of persistent velopharyngeal incompetence was successful in achieving good speech results.

Improving access to optometry services for people at risk of preventable sight loss: a qualitative study in five UK locations

Background

Reducing preventable sight loss is an increasing priority for public health and health care providers. We examined the factors affecting people's use of optometry services in population groups at increased risk of sight loss.

Methods

This is a qualitative study in five UK locations. In England, participants were from the Pakistani and Black Caribbean communities; in Scotland from the Pakistani community; and in Northern Ireland and Wales from white socio-economically deprived communities. Thirty-four focus groups were conducted (n = 289). The study included people who attend optometry services and people not engaged with services.

Results

Barriers to access included limited awareness of eye health and eye disease, concern about the cost of spectacles and the appropriateness of optometry in a commercial setting. Attendance at the optometrist was primarily symptom led. A positive previous experience or continuing relationship with the optometrist helped to alleviate the barriers and promote attendance.

Conclusion

Addressing the disparity between the broader messages about eye health and the current perception of the function of optometry could help improve access to services. Uptake may be improved through the co-production of interventions that better resonate with local communities. Non-retail service delivery options should be explored.

Birth prevalence of cleft lip and palate in Northern Ireland (1981 to 2000)

OBJECTIVE

The prevalence of cleft lip and/or palate (CL/P) in Northern Ireland (NI) was last reported for 1980 through 1990. This study was undertaken to update the prevalence of CL/P in NI for the 20-year period 1981 to 2000, to determine the pattern of prevalence, and to report the proportion of different cleft types and sex distribution.

DESIGN

Retrospective, population-based analysis.

PATIENTS/PARTICIPANTS

All live born children with CL/P in NI from 1981 to 2000 were included. A total of 750 cases were identified. Resident births outside NI, stillbirths, abortuses, and children born with atypical orofacial clefts were excluded. Those with syndromes and submucous clefts were included in the study.

RESULTS

The overall prevalence of children born with CL/P within NI for the period 1981 to 2000 was 1.47 per 1000 live births, or 1:682. This was consistent with the findings reported by other U.K. studies. There were no significant changes in the prevalence rates over any 5-year period. No significant seasonality trends were noted. Clefts of the palate only were always in the majority. More boys than girls were affected by cleft lip with or without cleft palate. There was a significant left-sided predilection for unilateral clefting of the lip.

CONCLUSIONS

There have been no significant changes in the birth prevalence of children born with CL/P or the distribution or laterality of cleft type in the NI population during the past 20 years.

DNA strand breaks, oxidative damage, and 1-OH pyrene in roofers with coal-tar pitch dust and/or asphalt fume exposure

OBJECTIVE

To determine the potential for asphalt fume exposure to increase DNA damage, we conducted a cross-sectional study of roofers involved in the application of roofing asphalt.

METHODS

DNA strand breaks and the ratio of 8-hydroxydeoxyguanosine (8-OHdG) to 2-deoxyguanosine (dG) were measured in peripheral blood leukocytes of roofers. In addition, urinary excretion of 8-OHdG and 8-epi-prostaglandin F2alpha (8-epi-PGF) was also measured. The study population consisted of 26 roofers exposed to roofing asphalt and 15 construction workers not exposed to asphalt during the past 5 years. A subset of asphalt roofers (n = 19) was exposed to coal-tar pitch dust (coal tar) during removal of existing roofs prior to applying hot asphalt. Personal air monitoring was performed for one work-week to measure exposure to total particulates, benzene-soluble fraction of total particulates, and polycyclic aromatic compounds (PACs). Urinary 1-OH-pyrene levels were measured as an internal biomarker of PAC exposure.

RESULTS

Full-shift breathing zone measurements for total particulates, benzene-solubles and PACs were significantly higher for coal-tar exposed workers than for roofers not exposed to coal tar. Similarly, urinary 1-OH-pyrene levels were higher in coal-tar exposed roofers than roofers not exposed to coal tar. Total particulates or benzene-soluble fractions were not associated with urinary 1-OH-pyrene, but PAC exposure was highly correlated with urinary 1-OH-pyrene. When stratified by 1-OH-pyrene excretion, DNA strand breaks increased in a dose-dependent manner, and leukocyte 8-OHdG/dG decreased in a dose-dependent manner. Significant changes in DNA damage appeared to be linked to PACs from coal-tar exposure, although asphalt fume alone was associated with a small but significant increase in urinary 1-OH-pyrene and DNA strand breaks.

CONCLUSIONS

Results are consistent with previous reports that asphalt or coal-tar exposure can cause DNA damage. Urinary 8-epi-PGF remained relatively constant during the week for virtually all subjects, regardless of exposure indicating that neither asphalt nor coal-tar exposure induces an overt oxidative stress. A small, but statistically significant increase in 8OHdG was evident in end-of-week urine samples compared with start-of-week urine samples in roofers exposed to coal-tar. The increase in urinary 8OHdG coupled with the decrease in leukocyte 8-OHdG/dG, suggests that coal-tar exposure induces protective or repair mechanisms that result in reduced levels of steady-state oxidative-DNA damage.

Impact of a formulary change in proton pump inhibitors on health care costs and patients' symptoms

Patients may fail to successfully undergo a switch in therapy associated with a formulary change. The aim of this study was to measure health care costs and outcomes among patients who failed a formulary change in proton pump inhibitors in a VA medical center. Patients who failed a switch from omeprazole to lansoprazole (N = 51) were matched with patients who were successfully switched (N = 51). Health care utilization data was gathered from VA electronic databases and medical records for six months before and after the switch and, for failure patients, during the lansoprazole trial period. Statistical comparisons between failure and success patients were performed on changes in health care costs between these time periods. Health outcome data for the lansoprazole trial period and subsequent omeprazole reinstatement period were obtained through a telephone questionnaire of failure patients. Changes in total health care utilization costs did not differ significantly between failure and success groups for any of the time periods. Failure patients had significantly poorer health outcomes during their lansoprazole trial periods with significantly greater severity of heartburn and severity and frequency of acid regurgitation (P < 0.001). In conclusion, the formulary change had a negative impact upon health outcomes among failure patients but did not significantly affect their health care utilization costs. Identification of failure patients early in their lansoprazole trial periods could improved their health outcomes and satisfaction with medical care.

Cervical cytology history in Irish doctors and midwives

In Ireland we do not have a national cervical screening programme. It is hoped that such a service will soon be implemented and a pilot programme is currently underway. In our department there was a perception that many women working in the area of women's health had a "laissez-faire" attitude towards their own cervical cytology. This prompted us to perform an anonymous survey of a sample of Irish gynaecologists, general practitioners and midwives in advance of a national cervical screening programme. Overall, 80% of the questionnaires were returned completed--72% from gynaecologists, 68% from GPs and 100% from midwives. 60% of those who returned completed questionnaires were "up-to-date", 21% were "late" and 19% had never had a cervical smear.

"A satellite primer on tuberculosis:" a collaboration in distance education

"A Satellite Primer on Tuberculosis" was offered as a distance-based certificate course on tuberculosis (TB) fundamentals to a national audience of over 5,000 individuals. The course was a collaborative effort of a school of public health, a state health department, and the Centers for Disease Control and Prevention. Instruction was provided through print-based self-study modules that were complemented by live, interactive satellite conferences. Course completers, over 70 percent of whom were nurses and employees of public health departments, scored significantly higher on a course posttest than on a pretest, and the vast majority felt the course provided valuable training.

Mutation screening of interferon-gamma (IFNgamma) as a candidate gene for asthma

BACKGROUND

Reduced levels of interferon gamma (IFNgamma) mRNA and protein have been detected in the bronchoalveolar lavage fluid of atopic asthmatics. IFNgamma is secreted by TH1 cells while IL-4 and IL-5 are secreted by TH2 cells and an imbalance in the TH1/TH2 response may be responsible for atopic asthma. The gene for IFNgamma is located on chromosome 12; a region of the genome which has been shown in linkage studies to be associated with asthma.

OBJECTIVE

To determine if there are any mutations present in the coding exons and 5' flanking region of the IFNgamma gene in atopic asthmatic subjects compared with controls to explain the lower levels of this cytokine as an inherited, rather than acquired, factor in the asthmatic subjects.

METHODS

The four exons and 5' flanking region of the IFNgamma gene were amplified by polymerase chain reaction (PCR) from genomic DNA of 265 individuals from a Western Australian and a Venezuelan population. The PCR products were examined by single strand conformational polymorphism and heteroduplex analyses to see if there were any changes in the DNA migration patterns which would suggest the presence of a sequence variation.

RESULTS

The four exons and the 5' flanking region of the IFNgamma gene were amplified from 265 individuals from two populations. Single strand conformational polymorphism and heteroduplex analyses did not reveal any mutations in the regions examined.

CONCLUSION

The gene for IFNgamma appears to be highly conserved as no sequence variations were detected in 265 individuals. These results suggest that mutations of the IFNgamma gene are unlikely to be a significant cause of an inherited asthma diathesis.

Proliferative indices and oncoprotein expression in benign and malignant breast biopsies

BACKGROUND

Prognostic factors are used routinely in the management of breast cancer. However, their potential for identifying precursor malignant lesions has not been assessed.

METHODS

We have examined 285 breast biopsy specimens (140 benign, 145 malignant) for DNA ploidy, S-phase fraction, Ki-67 nuclear antigen proliferative indices, and HER-2/neu and epidermal growth factor receptor oncoproteins.

RESULTS

When proliferative indices were compared between the benign and malignant groups, differences were noted for DNA ploidy, S-phase fraction, and cell cycling index (p < 0.0005). When the benign nonproliferative specimens were compared with the atypical/proliferative benign specimens, proliferative indices failed to show any differences. When the specific subset of proliferative/atypical benign breast tissue was compared with the malignant specimens, DNA index, S-phase fraction, and cell cycling index showed significant differences. The mean for epidermal growth factor receptor was greater in the non-proliferative group but not statistically significant (p < 0.1). HER-2/neu oncoprotein failed to show any differences between the benign and malignant groups. Within the atypical benign group, Ki-67 correlated strongly with S-phase fraction and HER-2/neu (p < 0.01).

CONCLUSIONS

We have demonstrated that proliferative indices can differentiate between benign and malignant breast tissues but not among specific subgroups. In addition, epidermal growth factor may differentiate between nonproliferative and proliferative/atypical benign biopsy results. Oncoprotein determination, ploidy, and DNA proliferative indices may be useful in defining malignant and benign breast disease but are not useful in distinguishing between benign and malignant breast disease with an increased likelihood for malignant transformation.

Secretion of phospholipase C by Pseudomonas aeruginosa

The conditions necessary for the secretion of phospholipase C (phosphatidylcholine cholinephosphohydrolase) by Pseudomonas aeruginosa were studied. Enzyme secretion by washed cell suspensions required a carbon source and ammonium, potassium, and calcium ions. The calcium requirement could be substituted by magnesium and strontium but not by copper, manganese, cobalt, or zinc. During growth in liquid medium, cells secreted phospholipase C during late logarithmic and early stationary phases. Secretion was repressed by the addition of inorganic phosphate but not by organic phosphates, glucose, or sodium succinate. Studies with tetracycline indicated that de novo protein synthesis was necessary for the secretion of phospholipase C and that the exoenzyme was not released from a preformed periplasmic pool. Similarly, extraction of actively secreting cells with 0.2 M MgCl2 at pH 8.4 solubilized large quantities of the periplasmic enzyme alkaline phosphatase but insignificant amounts of phospholipase C. Bacteria continued to secrete enzyme for nearly 45 min after the addition of inorganic phosphate or rifampin.