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At least 721 records · Page 40Linked to original sources
PubMed1999

Changing paternity and the risk of preterm delivery in the subsequent pregnancy.

I studied whether changing a partner, and thus changing the likelihood of human leukocyte antigen (HLA) sharing between mating partners, affects the risk of preterm delivery in the subsequent pregnancy. I identified a total of 128,239 women who had two consecutive births during 1989-1991 through data linkage of the California birth certificates. Paternal date of birth and names on the records of the two consecutive births were compared to determine whether the same father was reported on both records. Three cohorts of women were formed on the basis of the gestational age of their first delivery: <34, 34-36, and >36 weeks. If parental HLA sharing is associated with preterm delivery, the likelihood of HLA sharing was expected to be in a decreasing order from most likely among a <34-week cohort to least likely among a >36-week cohort. Among women in the <34-week cohort, changing partners resulted in a 33% reduction in the risk of early preterm delivery in the subsequent pregnancy compared with those who did not change partners [95% confidence interval (CI), 0.52-0.88]. In contrast, among women in the >36-week cohort, changing partners led to a 16% increase in the risk of early preterm delivery in the subsequent pregnancy (95% CI = 1.04-1.30). Among women in the 34-36-week cohort, changing partners did not affect the risk of preterm delivery (95% CI = 0.78-1.25). These estimates were adjusted for maternal race/ethnicity, age, educational level, prenatal smoking, prenatal care, parity, and interval from birth to conception of the subsequent pregnancy. The findings from this study suggest that the effect of changing paternity depends on the pregnancy outcome with the previous partner and support the hypothesis that parental HLA sharing may be related to preterm delivery.

Adult↗
PubMed1999

Suicides among Canadian farm operators.

The objective of this epidemiologic study was to describe rates of suicide among male farm operators in Canada and to compare rates with those in the general male population. The data were obtained from the Canadian Farm Operator Cohort (CFOC) database. Outcome measures were age-specific and age-standardized rates of completed suicide (ICD-9-CM E-codes 950-959). A total of 1,457 cases of suicide were identified from the CFOC for the years 1971- 1987. Age-standardized rates of suicide for those aged 30-69 were 29.2 (95% CI = 27.3-31.1) per 100,000 person-years (PYs) in the CFOC, 24. 0 (95% CI = 22.1-25.8) per 100,000 PYs in the CFOC excluding Quebec (which had data linkage concerns) and 27.0 (95% CI = 26.6-27.3) per 100,000 PYs among Canadian males in general. Age-specific rates of suicide in the CFOC increased over time. After adjustment for age differences, provincial suicide rates among farm operators were generally lower than or equivalent to those observed in the comparison populations of Canadian males. The implications of these results are discussed. We speculate that high levels of social support traditionally available in Canadian farm communities may protect farm operators from abnormally high rates of suicide.

Adult↗
PubMed2000

Evaluation of human diacylglycerol kinase(iota), DGKI, a homolog of Drosophila rdgA, in inherited retinopathy mapping to 7q.

PURPOSE: To determine the genomic organization of diacylglycerol kinase(iota) and to test whether defects in this gene are present in individuals affected with autosomal dominant retinitis pigmentosa (adRP). Diacylglycerol kinase(iota) has been mapped to the RP10 locus on 7q and shows 49% sequence similarity to the Drosophila DGK2 rdgA gene. Since mutations in the DGK2 rdgA gene cause photoreceptor degeneration in Drosophila, it is possible that mutations in diacylglycerol kinase(iota) could be responsible for human retinal degeneration. METHODS: DNA sequence from genomic clones containing diacylglycerol kinase(iota) was compared with the cDNA sequence to identify intron/exon boundaries. Single-strand conformational analysis and PCR product sequencing were used to screen members of one family previously mapped to the RP10 locus and 47 small unmapped families with autosomal dominant retinitis pigmentosa. RESULTS: Diacylglycerol kinase(iota) is divided into 35 exons with the initiation codon being present in exon 2. Mutational analysis found a missense change (Lys153Phe) in three adRP families; however, it did not segregate with disease in one of the families. Silent substitutions were seen in codons 865 and 875. Intronic variation was detected in the amplifications of exons 3,5,18, 28, and 32; these do not affect splice site consensus sequences. Typing of a polymorphic variant detected in intron 31 in members of the RP10 family gave a LOD score of -4.2 at 0% recombination. CONCLUSIONS: No evidence of disease-associated mutations was found in any of the samples tested. Based on the linkage data and mutation screening, diacylglycerol kinase(iota) is excluded as a candidate for the RP10 form of adRP and cannot be a frequent cause of other forms of adRP. Mutations in diacylglycerol kinase(iota) may yet be the cause of recessive forms of retinal degeneration in humans, either in homozygous or compound heterozygous forms. The data provided here will permit testing of this hypothesis.

Adult↗
PubMed2001

Undiagnosed diabetes: does it matter?

BACKGROUND: The 1998 Canadian clinical practice guidelines for the management of diabetes lowered the cutoff point for diagnosing diabetes mellitus from a fasting plasma glucose (FPG) level of 7.8 to 7.0 mmol/L. We studied the prevalence and clinical outcomes of undiagnosed and diagnosed diabetes within specific ranges of FPG among a cohort of subjects recruited in 1990. METHODS: In 1990 a representative sample of 2792 adult residents of Manitoba participated in the Manitoba Heart Health Survey, which included measurement of FPG and a question about each participant's past history of diabetes. Individuals who would now be classified as having undiagnosed diabetes under the new criteria were not considered as such in 1990. Through data linkage with the provincial health care utilization database, the use of health care by these individuals was tracked and compared with that of individuals whose diabetes had been diagnosed and with that of normoglycemic individuals over an 8-year period subsequent to the survey. RESULTS: The prevalence of undiagnosed diabetes in the adult population of Manitoba was 2.2%. Undiagnosed cases accounted for about one-third of all diabetes cases. Individuals with undiagnosed diabetes had an unfavourable lipid profile and higher blood pressure and obesity indices than normoglycemic individuals. Individuals who satisfied the new criteria for diabetes but remained undiagnosed had an additional 1.35 physician visits per year (95% confidence interval [95% CI] 0.93-1.96) and were more likely to be admitted to hospital at least once (odds ratio 1.23, 95% CI 0.40-3.79), compared with normoglycemic individuals. INTERPRETATION: Undiagnosed cases represent the unseen but clinically important burden of diabetes, with significant concurrent metabolic derangements and a long-term impact on health care use.

Adult↗
PubMed2001

Retrieval-oriented design of clinical research forms.

Computerized clinical forms are subject to a wide variety of different requirements. They have to allow detailed documentation and must be user-friendly. State-of-the-art applications for design permit clinicians themselves to create their own forms as needed, with the various variables presented in different ways depending on their intended use. Often, however, only aspects of clinical documentation are considered, with no thought being given to subsequent data retrieval. This article presents guidelines for the retrieval-oriented design of clinical forms. It discusses where anticipatory measures for structuring forms are easier to accomplish than complex data linkage at the time of retrieval and analysis.

Austria↗
PubMed2002

The medical care cost of childhood and adolescent cancer in Manitoba, 1990-1995.

The main purpose of this study is to estimate the medical care costs of childhood and adolescent cancer in Manitoba, and to determine the elements that influence these costs. Retrospective chart reviews were done to obtain all the information. A total of 118 childhood (age 0-14 years) and 41 adolescent (age 15-19 years) cancer patients were included. For childhood cancer, in-patient hospitalizations accounted for 59% of the total cost, followed by bone marrow transplant (BMT) (9%), medications (8%), laboratory investigations (7%) and physician fees (7%). For adolescent cancer, in-patient hospitalization accounted for 37% of the total cost, followed by bone marrow transplant (BMT) (25%), physicians' fees (11%), medications (9%) and laboratory investigations (7%). Overall, the average cost for the first, second and third year following diagnosis was $50,902 (median 35,708), $13,939 (4,127) and $6,769 (2,565) respectively for childhood cancer patients, and $57,354 (24,192), $16,888 (3,267) and $3,436 (3,267) respectively for adolescent cancer patients. Further work involving long-term data linkage of medical charts with hospital and clinic financial billing codes is needed to provide more accurate estimates of the costs of childhood and adolescent cancer care.

Adolescent↗
PubMedDate not supplied

[The pattern of use of emergency department in the local unit of Como].

The pattern of use of emergency department of hospitals is on the agenda of policy makers at national, regional and local level. It is still difficult to achieve a balance between the claim for improving the accessibility in order to allow people in need to receive this level of care and the possible its inappropriate use. The triage procedure offers the possibility to assess priorities because the "white codex" identifies those whose access to emergency department could potentially be diverted to an other level of care. The use of the Emergency Department is studied in an affluent area of Northern Italy using an "ad hoc" tool and data linkage in order to describe the process and its possible failures. The results are aimed to give decision makers the opportunity to start addressing these issues on sounder bases particularly as far as triage based assessment is concerned.

Adult↗
PubMed1991

Incidence of psoriasis in Rochester, Minn, 1980-1983.

This population-based study was carried out using the medical records linkage data resource for the population of Rochester, Minn, at Mayo Clinic. There were 132 newly diagnosed cases of psoriasis identified during a 4-year period (1980 through 1983); 88% of the cases had been seen and diagnosed by a dermatologist. The overall crude incidence rate was 57.6 per 100,000 population; for men and women, the rates were 54.4 and 60.2, respectively. The overall sex- and age-adjusted (1980 US white population) incidence rate was 60.4 per 100,000 person-years. The highest rate of occurrence (112.6) was in the 60- to 69-year-old age group. Most of the cases of psoriasis diagnosed in this study (58%) were mild, and the patients had psoriatic lesions on less than 10% of their body. There are no other published incidence rates for this condition with which to make comparisons.

Adult↗
PubMed1991

Marfan syndrome: no evidence for heterogeneity in different populations, and more precise mapping of the gene.

Marfan syndrome is a dominantly inherited connective tissue disorder with manifestations in the cardiovascular, ocular, and skeletal systems. The diagnosis is hampered by both high variability in the phenotypic expression and late manifestation of symptoms. The cause of Marfan syndrome remains unknown, but our group has recently reported the genetic linkage of Marfan syndrome to a polymorphic marker on chromosome 15. To analyze the possible heterogeneity behind Marfan syndrome, we have performed linkage analyses for four chromosome 15 markers in 17 families from five different populations: Scottish, English, Swiss, American, and Finnish. By combining the linkage data of all the studied families into a LINKMAP analysis we obtained a maximal LOD score of 11.2, which maps the Marfan syndrome locus between D15S25 and D15S45 on the long arm of chromosome 15. The data reveal no evidence for genetic heterogeneity behind Marfan syndrome and provide us with a more precise location of both the Marfan syndrome locus and flanking markers. This information will provide the basis for the DNA diagnostics of Marfan syndrome in the future.

Chromosome Mapping↗
PubMed1991

Assessment of chronic gamma radiosensitivity as an in vitro assay for heterozygote identification of ataxia-telangiectasia.

Ataxia-telangiectasia (A-T) is a rare human autosomal recessive disorder characterized by, among other symptoms, catastrophic reaction to conventional radiotherapy. A-T heterozygotes are clinically asymptomatic and their fibroblasts are intermediate in radiosensitivity between homozygotes and normals. We have attempted to identify heterozygotes by assaying for cellular hypersensitivity to chronic gamma irradiation. Cultured dermal fibroblast strains from 13 control subjects and 55 members from a large Amish pedigree segregating for A-T were assayed for loss of colony-forming ability (CFA) in response to 137Cs gamma radiation delivered at a dose rate of 0.8 cGy/min. For each strain, multiple dose-response curves were summarized in a composite D10 value (dose, in cGy, reducing colony survival to 10%). The D10's of the clinically normal controls and of those pedigree members with known A-T genotype formed a trimodal distribution, with the seven obligate heterozygotes displaying an average value (516 cGy) intermediate between that of the 10 healthy controls (797 cGy) and that of the two affected patients (154 cGy). The D10's were modeled statistically using Gaussian penetrance functions. The most parsimonious model yielded a significant difference in D10 means for heterozygotes and normal homozygotes, a significant donor age effect, but no sex effect. We compared probabilistic identification of heterozygotes based on D10 values with identification based on linkage data for two markers, THY1 and D11S144, closely linked to the A-T gene. This comparison revealed that the D10 data were appreciably less informative than the linked markers. Indeed, the extensive overlap between D10 values for heterozygotes and normal homozygotes precludes the use of postirradiation CFA for either accurate identification of heterozygotes or chromosomal mapping of the A-T gene.

Ataxia Telangiectasia↗
PubMed1991

Influence of aberrant observations on high-resolution linkage analysis outcomes.

Because of the availability of efficient, user-friendly computer analysis programs, the construction of multilocus human genetic maps has become commonplace. At the level of resolution at which most of these maps have been developed, the methods have proved to be robust. This may not be true in the construction of high-resolution linkage maps (3-cM interlocus resolution or less). High-resolution meiotic maps, by definition, have a low probability of recombination occurring in an interval. As such, even low frequencies of errors in typing (1.5% or less) may influence mapping outcomes. To investigate the influence of aberrant observations on high-resolution maps, a Monte Carlo simulation analysis of multipoint linkage data was performed. Introduction of error was observed to reduce power to discriminate orders, dramatically inflate map length, and provide significant support for incorrect over correct orders. These results appear to be due to the misclassification of nonrecombinant gametes as multiple recombinants. Chi 2-Like goodness-of-fit analysis appears to be quite sensitive to the appearance of misclassified gametes, providing a simple test for aberrant data sets. Multiple pairwise likelihood analysis appears to be less sensitive than does multipoint analysis and may serve as a check for map validity.

Algorithms↗
PubMed1991

Amplification at chromosome 11q13 in transitional cell tumours of the bladder.

Amplification of several markers which map to chromosome 11q13 was detected by Southern blotting in transitional cell tumours of the urinary bladder. The oncogenes INT2 and HST and the BCL1 locus were co-amplified in 20/97 (20.6%) tumours and the locus-specific minisatellite probe pMS51 (D11S97) detected amplification in 17/97 (17.5%) tumours. The high frequency of heterozygosity (greater than 70%) detected by this latter probe on HaeIII-digested DNAs provided a sensitive means to measure low levels of gene amplification (2-fold) by comparing signals obtained from each allele. A number of probes which map to 11q were used in an attempt to map the region of amplification more precisely. PGA, PGR, STMY, D11Z1 and D11S149 were not amplified in any tumours studied. SEA was amplified in 1/59 tumours and D11S146 in 12/89 tumours. A comparison of the patterns of co-amplification of individual markers in this series of tumours revealed that of the 23 tumours with amplification at this site, 11 had co-amplification of D11S97, D11S146, BCL1, INT2 and HST, 3 had co-amplification of D11S97, BCL1, INT2 and HST, 6 had co-amplification of BCL1, INT2 and HST, 1 had co-amplification of D11S97 and D11S146 and 2 had amplification of D11S97 alone. Based on available linkage data for these markers, this suggests that a putative target gene within this amplicon lies centromeric to BCL1. Amplification at 11q13 showed no correlation with tumour grade or with HER2 amplification.

Blotting, Southern↗
PubMed1989

Relative predispositional effects (RPEs) of marker alleles with disease: HLA-DR alleles and Graves disease.

A method is described to reveal the relative predispositional effects (RPEs) (predisposing, protective, or neutral) of the HLA alleles or of any other marker system that is associated with a disease. When the disease is associated with two or more alleles of a locus, the RPE method identifies the associations sequentially according to their strength; thus the problem that a strong association with one allele can create misleading deviations in the frequencies of other alleles is alleviated. Using this method, we have examined the relative effects of HLA-DR alleles in susceptibility to Graves disease in the Caucasian population. The well-established positive association with DR3 was confirmed as the strongest effect. In addition, a negative association was found between DR5 and Graves disease. The reduced frequency of DR5 among patients is statistically significant and is not a result of the increase in DR3. Finally, when patients were divided according to the presence or absence of eye disease, the latter showed a significant increase in the frequency of DR4. With family data, linkage to HLA of Graves disease was established in both Caucasian and Chinese families by the sib-pair method.

Alleles↗