Biomedical subjects
Publications and source records attributed to R North.
Twins show differences in physiological maturity within and between twin sets; where one infant is 5-weeks later than its sibling; while one pair may both be slow but develop together. Zygosity, birth weight and sex may be contributory but not causative factors. How vulnerability to illness may be affected, is discussed.
Epidemiological studies have shown that genetic factors contribute to the etiology of the common and serious pregnancy-specific disorder pre-eclampsia (PE)/eclampsia (E). Candidate-gene studies have provided evidence (albeit controversial) of linkage to several genes, including angiotensinogen on 1q42-43 and eNOS on 7q36. A recent medium-density genome scan in Icelandic families identified significant linkage to D2S286 (at 94.05 cM) on chromosome 2p12 and suggestive linkage to D2S321 (at 157.5 cM) on chromosome 2q23. In the present article, the authors report the results of a medium-density genome scan in 34 families, representing 121 affected women, from Australia and New Zealand. Multipoint nonparametric linkage analysis, using the GENEHUNTER-PLUS program, showed suggestive evidence of linkage to chromosome 2 (LOD=2.58), at 144.7 cM, between D2S112 and D2S151, and to chromosome 11q23-24, between D11S925 and D11S4151 (LOD=2.02 at 121.3 cM). Given the limited precision of estimates of the map location of disease-predisposing loci for complex traits, the present finding on chromosome 2 is consistent with the finding from the Icelandic study, and it may represent evidence of the same locus segregating in the population from Australia and New Zealand. The authors propose that the PE/E-linked locus on chromosome 2p should be designated the "PREG1" (pre-eclampsia, eclampsia gene 1) locus.
OBJECTIVES: Firstly, to compare pregnancy outcomes and cardiac complications in women with: 1) either mechanical or bioprosthetic valves at the mitral site; 2) mechanical valves treated with warfarin or subcutaneous heparin. Secondly, to determine pregnancy and cardiac outcomes in women with aortic homograft valves. DESIGN: Historical cohort study. SETTING: Greenlane Hospital, Auckland, New Zealand. POPULATION: Young women (n = 255) who had valve replacements between 1972 and 1992. Seventy-nine women underwent 147 pregnancies. MAIN OUTCOME MEASURES: Pregnancy loss, cardiac complications. RESULTS: Pregnancy loss occurred in 59% of pregnancies with mitral mechanical valves (n = 50) and 7% with mitral bioprosthetic valves (n = 33) (RR 8 x 20, 95% CI 2 x 10-31 x 93). Pregnancy loss rate was 70% in pregnancies treated with warfarin, compared with 25% for those switched from warfarin to heparin (RR 2 x 81, 95% CI 1 x 03-7 x 73). All heparin-associated losses occurred in the first trimester, whereas there were four stillbirths with warfarin. Cardiac complications occurred in 10 pregnancies (20%) in the women with mitral mechanical valves and four (13%) with mitral bioprosthetic valves (RR 1 x 55, 95% CI 0 x 53-4 x 52). All four thromboembolic complications with mechanical valves occurred in the 14 women treated with heparin throughout pregnancy. Structural valve deterioration occurred in four pregnancies (10%) with mitral bioprosthetic valves. No cardiac complications or known pregnancy losses occurred with aortic homograft valves (n = 41). CONCLUSION: The high pregnancy loss rate in women with mitral mechanical valves was associated with warfarin throughout pregnancy, whereas the thromboembolic cardiac complications were associated with heparin. Pregnancy outcome was very good in women with bioprosthetic and homograft valves.
Essential thrombocythaemia is a rare myeloproliferative disorder that often presents with haemorrhagic or thrombotic complications. It may be detected incidentally in an asymptomatic younger adult and there are only a few case reports of essential thrombocythaemia in pregnant women. The risks posed by essential thrombocythaemia during pregnancy and its optimal management are uncertain. To determine if there is increased incidence of obstetric complications seen in women who have essential thrombocythaemia, we collected a large case series from a number of tertiary obstetric units in Australia and New Zealand. There were 30 pregnancies in 12 women who had essential thrombocythaemia. There were 17 live births (57%), 7 stillbirths (23%), 5 miscarriages (17%) and 1 ectopic (3%). Five pregnancies were complicated by placental abruption. When the outcomes of those women who received treatment with aspirin or interferon were compared to those that did not receive any treatment, there was a trend towards a higher livebirth rate (79% v. 38%, p = 0.06). Seven women were treated with aspirin and 5 had successful outcomes with no fetal complications. Four women were treated with alpha-interferon which reduced their platelet counts and all had successful outcomes with no fetal complication. These findings suggest that there is a high incidence of miscarriage, stillbirth and abruption in women with essential thrombocythaemia. Their pregnancies should be carefully monitored. Treatment with low dose aspirin and/or the use of alpha-interferon may be associated with an improved pregnancy outcome.
OBJECTIVE: A strong independent association between the prothrombin G20210A gene mutation and pre-eclampsia has been reported in an Italian population. This result was not confirmed in a subsequent study in a Dutch population. The objective of this study was to further test the hypothesis that the prothrombin G20210A mutation is associated with pre-eclampsia/eclampsia. METHODS: Seventeen eclamptics and 67 pre-eclamptics were recruited from 34 multicase Australian/New Zealand families. An additional 105 unrelated pre-eclamptic/eclamptic women and 119 parous women were recruited as controls. RESULTS: The overall incidence for the prothrombin G20210A gene mutation in the pre-eclamptic group was 3.6% (95% CI 1.2-8.2%) which was not significantly different from the control group 2.5% (95% CI 0.5-7.2%) (p = 0.73, OR 1.44, 95% CI 0.34-6.17). CONCLUSION: This study provides little evidence of a significant relationship between the prothrombin G20210A gene mutation and pre-eclampsia. Based on our results, we do not recommend testing for the prothrombin G20210A mutation in the routine investigation of women with pre-eclampsia.
In this report, the author, Executive Vice President of the American Cancer Society in Oregon, reviews the key factors in the crafting of the coalition leading to passage of a tobacco tax in Oregon. Mr. North also emphasizes the importance of institutionalizing the coalition after passage to provide the required leadership for future efforts.
Monocyte chemoattractant protein 1 (MCP-1) is a CC chemokine that attracts monocytes, memory T lymphocytes, and natural killer cells. Because other chemokines have similar target cell specificities and because CCR2, a cloned MCP-1 receptor, binds other ligands, it has been uncertain whether MCP-1 plays a unique role in recruiting mononuclear cells in vivo. To address this question, we disrupted SCYA2 (the gene encoding MCP-1) and tested MCP-1-deficient mice in models of inflammation. Despite normal numbers of circulating leukocytes and resident macrophages, MCP-1(-/-) mice were specifically unable to recruit monocytes 72 h after intraperitoneal thioglycollate administration. Similarly, accumulation of F4/80+ monocytes in delayed-type hypersensitivity lesions was impaired, although the swelling response was normal. Development of secondary pulmonary granulomata in response to Schistosoma mansoni eggs was blunted in MCP-1(-/-) mice, as was expression of IL-4, IL-5, and interferon gamma in splenocytes. In contrast, MCP-1(-/-) mice were indistinguishable from wild-type mice in their ability to clear Mycobacterium tuberculosis. Our data indicate that MCP-1 is uniquely essential for monocyte recruitment in several inflammatory models in vivo and influences expression of cytokines related to T helper responses.
This report concerns 37 children and teenagers operated upon for intractable seizures between 1990 and 1994. Follow-up is at least 3 years. Fourteen children underwent pure temporal lobe resections; 71% are seizure free, and 93% have a better than 90% decrease in seizure frequency. The presence of a lesion on magnetic resonance imaging, the side of the lesion, or the presence of abnormal pathology had no influence on the result of resection. 28% of the children who had extratemporal resections are seizure free, and 83% have a greater than 90% decrease in seizure frequency. There was a trend to better results in those with a lesion on magnetic resonance imaging. In the small group with temporal plus extratemporal foci, the results were poor with only 60% showing a greater than 90% reduction in seizure frequency.
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We report an unusual case of bilateral choroidal masses developing in a patient with metastatic prostate cancer. Visual symptoms resolved and ocular mass lesions regressed after initiating total androgen deprivation. The natural history and management of choroidal metastatis originating from prostate cancer is discussed.
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1. A heterogeneous group of randomized trials have been conducted using low-dose aspirin to prevent preeclampsia. The results do not support widespread use of low-dose aspirin to prevent preeclampsia. 2. On the basis of existing literature, it is reasonable to use prophylactic low-dose aspirin from early pregnancy in the following groups: (i) Women with prior fetal loss after the first trimester, with placental insufficiency (ii) Women with severe fetal growth retardation in a preceding pregnancy either due to preeclampsia or unexplained (iii) Women with severe early-onset preeclampsia in a previous pregnancy necessitating delivery at or before 32 weeks' gestation. 3. On the basis of existing literature, it is recommended that aspirin not be used in the following groups: (i) Healthy nulliparous women (ii) Women with mild chronic hypertension (iii) Women with established preeclampsia. 4. The data are sufficient to support further trials in more homogeneous select subgroups of women considered at risk of developing preeclampsia.
The objective of this study was to examine the results of 16-channel computer-assisted outpatient long-term EEG monitoring (CO-LTM) and to compare those results to previously published reports using 4- and 8-channel ambulatory cassette-based continuous recordings. Patients were referred to a community-based outpatient EEG service for further diagnostic evaluation using this 16-channel bipolar recording system. 344 patients were recorded for an average of 1.4 days. EEG was reviewed for the presence of patient identified events, computer identified interictal and ictal abnormalities, and periodic time samples. A push-button recording that signified a clinical event was obtained in 166 patients (48.3%); 41 (11.9%) of these recordings included a seizure and 125 (36.3%) showed no EEG changes during the habitual event. An EEG abnormality was identified by the computer in an additional 90 recordings (26.2%), for an overall clinical usefulness of 74.4%. Among the 191 patients referred with previously normal routine EEGs, a total of 129 (67.5%) of these recordings were useful. 48 (25.1%) of these tracings were abnormal and an additional 81 push-button events (42.4%) showing no changes from background EEG were recorded. In conclusion, computer-assisted outpatient EEG monitoring provides good success rates for clinically useful information.
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Caprine arthritis-encephalitis virus (CAEV) was isolated by explant cultures of carpal synovial membranes and lung from 7 goats in New South Wales. These goats were clinically affected with the arthritic, neurologic, and pneumonic forms of CAEV infection either singly or in combination. CAEV antibody was detected by the gel immunodiffusion precipitin (GDP) test in 5 of the 7 goats. Serum samples from 2,708 goats, from 115 herds, were examined for CAEV antibody using the GDP test. Approximately one-third of the animals and 82% of the herds tested had CAEV antibody. The infection was common in all breeds of dairy goats with an indication of a significantly lower prevalence in the Saanen breed (24.4%) compared to Nubians, British Alpines and Toggenbergs (43.8%, 38.7% and 39.1% respectively). CAEV antibody was also demonstrated in 11 of 230 Angora goats. The infection was equally common in all age groups, with slightly higher prevalence in males (83 of 230, 36%) compared to females (648 of 2,232, 29%). Among seropositive animals 85% were clinically normal. Of 280 clinically affected goats tested only 42% had detectable antibody. One of 5 sheep that had been in contact with infected goats in one herd had CAEV serum antibody.
In previous studies we have shown that subjects with normal binocular vision adapt to prism-induced heterophorias. In this study we have continued the work by investigating whether the oculomotor system can also adapt to lens-induced heterophorias. It was found that subjects gradually adapted to the esophoria induced when viewing a distance chart through negative lenses. Adaptation also occurred to lens-induced esophoria and exophoria at near, while at distance, where the visual feedback was unaltered, the phoria remained virtually constant. These findings demonstrate the flexibility of the oculomotor system.
In a previous study we investigated how normal subjects adapted to prism-induced heterophoria. In this study we have continued this work by investigating this phenomena in 15 patients with abnormal binocular vision and/or asthenopia. It was found that the majority of subjects lacked or had a deficient adaptation system to base-in and/or base-out prisms, but all except two subjects examined adapted normally to vertical prism. These results suggest that it may be possible to treat the horizontal adaptation system independently from the vertical one. Prism vergences, heterophoria measurements, and the presence of fixation disparity gave little indication of the adaptation ability of the subjects. Symptoms correlated well with adaptation ability.
Patients who underwent implantation of dorsal column stimulators from 1970 to 1973 were reviewed 7-10 years following stimulation. The number who achieved satisfactory pain relief was not significant. The criteria for selecting these patients were reviewed utilizing those now used in 1980. 50% of the patients originally selected would now be rejected for psychological or drug-related reasons. This long-term evaluation indicates no benefit to the patients treated with spinal cord stimulation. However, it appears that psychological factors were the most important reasons for failure. A smaller group of patients studied for 3-5 years following implantation of epidural spinal cord stimulators achieved a 70% pain control rate. Selection factors that explain these differences are discussed.