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Biomedical subjects

E P Kirk

Publications and source records attributed to E P Kirk.

At least 19 recordsLinked to original sources
PubMed2006

The occurrence of congenital heart defects in an inbred herd of pigs in Australia.

OBJECTIVE: To report on the first case of congenital heart defects in pigs in Australia. DESIGN: Retrospective analysis of case records from an inbred herd of "Westran" pigs at the University of Sydney, between January 2001 and December 2004. Detailed gross and histological examination of 15 hearts from pigs that had died or were euthanased in 2004. CASE DETAILS: The necropsy records from a population of 471 pigs that had died (106 pigs) or were euthanased for research purposes (365 pigs) were analysed and the incidence of heart defects recorded, together with basic demographic data. No attempts were made to diagnose the condition in live pigs. RESULTS: Congenital heart defects were diagnosed in 6.4% of pigs but this is likely to be an underestimate of the incidence of the deformity. Eighteen pigs died on the farm as a result of the defect, and 12 pigs were diagnosed with the defect as an incidental finding. The most common abnormality seen at necropsy was a sac-like dilatation on the right lateral surface of the right atrium. This was associated with secondary deformity and hypoplasia of the adjacent left ventricle, interventricular region and part of the right ventricle. All hearts showed atrial septal defects of varying size. CONCLUSION: This is the first reported case of congenital heart defects in pigs in Australia, and one of less than five reported cases of atrial septal defects in pigs in the world. The authors conclude that there may be an element of genetic predisposition to the malformation, since it has only been reported in this inbred line of pigs.

Animals↗
PubMed2005

OPA3 mutation screening in patients with unexplained 3-methylglutaconic aciduria.

We have screened 13 patients with neurological abnormalities and 3-methylglutaconic aciduria (3MGA) for mutations in the OPA3 gene, which are known to be the cause of Costeff syndrome (optic atrophy, chorea and spasticity; type III 3MGA). We aimed to explore whether mutations in the OPA3 gene are present in patients with 3MGA but without classic Costeff syndrome. OPA3 mutations (IVS1-1G>C) were identified in 2 patients with the classic phenotype of type III 3MGA, but not in the other 11 patients with differing non-Costeff phenotypes associated with developmental delay and neurological signs and symptoms as described. We identified a previously described sequence variation in the OPA3 gene (c.231T>C) in 12/13 patients. The alteration was homozygous in 8/12 and heterozygous in 4/12. This alteration was also found in 60 of 98 normal control alleles. In a single patient, a novel sequence variation in the 5' UTR was identified, (c.-38A>G). Our studies suggest that the c.231T>C sequence variation is of no clinical significance, whereas the significance of the 5' UTR sequence variation remains open to speculation. Our study of the OPA3 gene in patients with 3MGA without Costeff syndrome suggests that mutations in OPA3 are not a common cause of 3MGA in the absence of signs of Costeff syndrome.

5' Untranslated Regions↗
PubMed2003

Time course for changes in aerobic capacity and body composition in overweight men and women in response to long-term exercise: the Midwest Exercise Trial (MET).

OBJECTIVE: To determine the time course for changes in aerobic capacity, body weight (BW), and composition in overweight adults in response to a supervised exercise trial with a targeted energy expenditure of 2000 kcal week(-1). DESIGN: The Midwest Exercise Trial (MET) was a randomized, controlled, 16-month verified, supervised exercise trial. Aerobic exercise progressed to 45 min day(-1), 5 days week(-1) over 6-months and was then maintained for 10 months. Controls maintained their normal physical activity and all participants maintained ad libitum diets. SUBJECTS: A total of 131 participants were randomized to exercise or control groups and 74 completed the intervention and all laboratory testing. MEASUREMENTS: At baseline and months 4, 9, 12, and 16, aerobic capacity (VO(2max) ) was measured by indirect calorimetry, BW by digital scale, and fat weight and fat-free weight by hydrostatic weighing. RESULTS: Aerobic capacity (ml kg(-1) min(-1)) increased (P<0.05) from baseline (39.2+/-5.2, mean+/-s.d.) to 9 months (48.8+/-4.3) in exercising men as well as women (32.8+/-4.2-39.6+/-5.5) with no significant changes occurring at 12 or 16 months. From baseline to 9 months BW (94.0+/-12.6-88.7+/-9.7 kg) and fat weight (26.8+/-6.8-21.8+/-4.5 kg) significantly decreased in exercising men with no changes occurring at 12 or 16 months. There were no changes in fat-free weight across the 16 months for exercising men or for BW or composition in exercising women. Further, there were no significant changes for the control men for aerobic capacity, BW, or body composition across 16 months. Women in the control group showed significant increases in weight of 2.9+/-5.5 kg and fat weight of 2.1+/-4.8 kg at 16 months only. CONCLUSIONS: We recommend that investigations that use exercise without diet as the stimulus for weight loss have at least a 9-month duration to provide sufficient time for the full effects to be realized, should such effects be present.

Adipose Tissue↗
PubMed2001

The relationships among working memory, math anxiety, and performance.

Individuals with high math anxiety demonstrated smaller working memory spans, especially when assessed with a computation-based span task. This reduced working memory capacity led to a pronounced increase in reaction time and errors when mental addition was performed concurrently with a memory load task. The effects of the reduction also generalized to a working memory-intensive transformation task. Overall, the results demonstrated that an individual difference variable, math anxiety, affects on-line performance in math-related tasks and that this effect is a transitory disruption of working memory. The authors consider a possible mechanism underlying this effect--disruption of central executive processes--and suggest that individual difference variables like math anxiety deserve greater empirical attention, especially on assessments of working memory capacity and functioning.

Adult↗
PubMed2001

Telling stories: the perils and promise of using verbal reports to study math strategies.

The problem size effect in adult arithmetic performance is generally attributed to direct retrieval processes operating on a network representation in long-term memory. J. LeFevre and her colleagues (J. LeFevre, J. Bisanz, et al., 1996; J. LeFevre, G. S. Sadesky, & J. Bisanz, 1996) challenged this explanation using verbal report evidence that adults also use time consuming nonretrieval strategies to solve simple addition and multiplication. The authors replicated J. LeFevre and colleagues' methods, but added instructional biasing and silent control conditions to test these methods. Both reaction time and report results suggest that LeFevre and colleagues' conclusions about nonretrieval frequency may have been influenced by instructions that revealed the experimental hypothesis and affected participants' strategy reports. Obtaining evidence about adult strategy use in simple arithmetic will require understanding instructional demand and appropriate report methodology.

Adult↗
PubMed1999

Severe micrognathia, cleft palate, absent olfactory tract, and abnormal rib development: cerebro-costo-mandibular syndrome or a new syndrome?

We report on a family in which two sibs had apparently absent ribs and severe micrognathia on prenatal ultrasonography. The pregnancies were terminated at 19 and 12 weeks of gestation, respectively. Autopsy findings in the first fetus (19 weeks of gestation) included severe micrognathia, a U-shaped defect of the soft palate, marked postnuchal edema, absent olfactory bulbs, and cribriform plate and rib abnormalities. The ribs consisted of cartilage anteriorly, with only a small amount of fibrous tissue present laterally and posteriorly. The second fetus (12 weeks gestation) had agnathia, with a large U-shaped defect in the soft palate. There was moderate postnuchal edema. The ribs were unossified and there were gaps in the cartilage where primitive mesenchyme was present posteriorly and laterally. These findings are consistent with a severe form of cerebro-costo-mandibular syndrome. The early fetal histopathology of both cases suggests a possible mechanism by which the characteristic "rib gaps" of cerebro-costo-mandibular syndrome may develop, with evidence for abnormal function of a gene or genes involved in regulation of rib chondrogenesis.

Abnormalities, Multiple↗
PubMed1999

Dominant inheritance of cleft palate with minor abnormalities of hands and feet: a new syndrome?

We report a family in which four members of three generations are affected by median cleft palate. The proband and her mother have additional features including bilateral single transverse palmar creases, broad great toes and hypoplastic fifth toenails. Dominant isolated cleft palate has rarely been reported, and there are no previous reports of dominant cleft palate with these associated features. We believe that this represents a previously unreported syndrome, which needs to be considered when assessing recurrence risk for cleft palate.

Adult↗
PubMed1998

X-linked adrenoleukodystrophy: the Australasian experience.

Our objective was to review the Australasian experience of X-linked adrenoleukodystrophy (ALD), to compare the spectrum of disease seen in Australasia with previously published data from elsewhere, and to assess the reliability of carrier testing. Study design was a retrospective review of records collected over a 15-year period, the setting was an international referral laboratory for the study of metabolic disease, and the subjects were all known cases of ALD diagnosed in Australia and New Zealand between 1981 and 1996 and their families. We estimate that the combined incidence of ALD and its variants in Australasia is at least 1.6 per 100,000. Of 95 affected males, 51 had cerebral adrenoleukodystrophy, 24 had adrenomyeloneuropathy, 15 had Addison's disease only, and 5 remained asymptomatic when last examined. However, the distribution of phenotypes among newly diagnosed patients has changed substantially over the last 15 years, with cerebral forms of the disease forming a decreasing proportion of new diagnoses. The measurement of plasma very long chain fatty acids (VLCFAs) alone detects 93% of women who can be proven to be carriers. The addition of genetic linkage studies or assay of VLCFAs in cultured fibroblasts improved this detection rate to the point that there were no obligate carriers who could not be detected using a combination of two or more techniques.

Adrenoleukodystrophy↗
PubMed1998

Obstetrician-gynecologists as primary care physicians: the Oregon experience--early perceptions regarding the effects of legislative action.

OBJECTIVE: Our purpose was to assess whether legislative action influenced the role of obstetrician-gynecologists as primary care physicians. STUDY DESIGN: An observational study was performed on the basis of a questionnaire sent to 410 obstetrician-gynecologists and 27 medical directors of managed-care organizations. RESULTS: Of 67% of obstetrician-gynecologists and 96% of medical directors who responded, there was agreement as to the content of primary care, but a minority (38%) of obstetrician-gynecologists identified themselves as primary care providers. A minority of medical directors (35%) felt that obstetrician-gynecologists should serve in that role. Both obstetrician-gynecologists and medical directors felt that legislation had little impact. CONCLUSION: The reticence of obstetrician-gynecologists to assume a major role in primary care appears to be the result of an uneasiness with accepting a more comprehensive role in patient management and gatekeeping. They appear comfortable with the more traditional roles but feel that training and experience has not prepared them well for the management of more complex medical problems.

Female↗
PubMed1993

Pregnancy after metroplasty for uterine anomalies.

OBJECTIVE: To clarify the relation between metroplasty for correction of uterine anomalies and subsequent pregnancy, we reviewed the charts of all patients for whom a diagnosis of bicornuate, septate, or didelphic uterus had been made between 1972 and 1982 and analyzed their obstetric outcomes. DESIGN: Of the 146 patients evaluated, 23 received a metroplasty procedure, and 123 patients did not have surgical intervention. Fifteen of the nonsurgical patients could be matched with 15 of the surgical patients by age, chief complaint, gravidity, and type of anomaly and therefore served as matched controls. RESULTS: The percentage of patients with living children after the diagnosis of uterine anomaly was 67% for the matched nonsurgical group and 73% for the patients who underwent metroplasty. The difference was not statistically significant. Although marked improvement in fetal salvage rates was noted when reproductive outcomes before and after metroplasty were compared, the obstetric outcome was similar to that of the control groups after the diagnosis was made and surgery deferred. CONCLUSION: The efficacy of metroplasty in the treatment of multiple pregnancy losses is thus being questioned.

Adult↗
PubMed1992

Vaginal PO2 in healthy women and in women infected with Trichomonas vaginalis: potential implications for metronidazole therapy.

We measured the PO2, pH, and temperature in the vaginal canals of nine patients with symptomatic Trichomonas vaginitis and those of 10 healthy women. The patients included eight women with primary infections caused by metronidazole-susceptible strains and one refractory case that resulted from infection with a metronidazole-resistant Trichomonas vaginalis. The median vaginal PO2, pH, and temperature in the patient group were 1 mm Hg, 6, and 37.3 degrees C respectively; these medians were 1 mm Hg, less than or equal to 4.5, and 37.2 degrees C in the healthy group. These data show that vaginal environment is anaerobic or microaerophilic (it has reduced oxygen tension). Because the activity of metronidazole is reduced under aerobiosis, the vaginal environment should enhance the biologic activity of the drug.

Adult↗
PubMed1991

Organ transplantation and pregnancy. A case report and review.

The 1980s has been described as the "decade of transplantation" and organ transplantation as a "paradigm of medical progress." The considerable improvements in immunosuppression that have been made in the last few years have led to an increased repertoire of organ-to-organ combination transplants, more procedures, and markedly increased survival time for both grafts and recipients. Inevitably, there will be an increased number of women recipients who later undergo pregnancy. Although there is a wide experience with pregnancy after renal transplantation, there are as yet relatively few reports of pregnancy after other major organ transplants. A case is presented of a 22-year-old primiparous woman who elected to conceive and complete a pregnancy 2 years after cardiac transplantation because of cardiomyopathy. The pregnancy was complicated by a rejection episode early in the third trimester but eventually resulted in forceps delivery of a live male infant at 41 weeks' gestation. The pregnancy and organ transplantation literature is reviewed with special attention, illustrated by the case report, to the physiologic adaptation to pregnancy of the transplanted organ, the potential teratogenic effects of the immunosuppressive drugs used in pregnancy, and the contrasts between renal and other major organ transplants.

Adaptation, Physiological↗