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Biomedical subjects

J Rice

Publications and source records attributed to J Rice.

At least 181 records · Page 10Linked to original sources
PubMed1982

Canine parvovirus infection potentiates canine distemper encephalitis attributable to modified live-virus vaccine.

Twelve gnotobiotic dogs from 2 litters were allotted to 3 groups. Group A dogs received a modified-live polyvalent (canine distemper, adenovirus type 2, and parainfluenza virus and Leptospira -canicola-icterohemorrhagiae bacterin) vaccine 3 days prior to oral inoculation with canine parvovirus (CPV). Group B dogs received CPV alone. Group C dogs received 1 dose of vaccine only. In none of the 9 CPV-inoculated dogs did clinical signs of CPV infection develop, although high serum antibody titers for CPV developed in all of them. However, in 2 of the 5 CPV-inoculated vaccinates, canine distemper virus encephalomyelitis subsequently developed. The results suggested that CPV exerts an immunomodulating effect on canine immune responses and may be responsible for vaccination failures in dogs.

Animals↗
PubMed1982

A commingling analysis of platelet monoamine oxidase activity.

The distribution of platelet monoamine oxidase (MAO) activity is examined in a large cohort of 18-year-olds from a college setting. A mixture of three distributions is needed to describe the data, even when a power transformation is used to remove skewness in the distribution. This is compatible with MAO activity being controlled by a single major locus with a gene frequency of 0.02 for high-MAO activity. Accordingly, it is unlikely that such a locus could serve as a genetic marker for a disorder which is associated with low activity. However, this finding does not rule out the possibility that MAO activity is an associated risk factor in disease.

Adult↗
PubMed1982

Ascertainment bias for non-twin relatives in twin proband studies.

When families are ascertained through affected twins, as for example when twin probands are selected from a registry and their non-twin relatives studied, a correction for ascertainment bias is needed. It is shown that probandwise counting (where relatives of doubly ascertained twin pairs are counted twice) is the appropriate method. The bias resulting from pairwise counting is given and depends on the genetic model and on the probability of selecting an affected twin as a proband. For the multifactorial and generalized single major locus models the bias is small, and the problems associated with nonindependent ascertainment are negligible in practice.

Chromosome Mapping↗
PubMed1982

Inhibiting effect of dehydroascorbic acid on cell division in ascites tumors in mice.

The transplantable murine ascites tumors, P388 leukemia and Ehrlich carcinoma, demonstrated complete inhibition of mitotic activity after treatment with dehydroascorbic acid in mice. Citric acid at the same pH value (2.4), however, showed no diminution of mitoses. Microscopic examination of the stained ascites exudate taken from the mice treated with 10 mg dehydroascorbic acid revealed few tumor cells and a pronounced increase in white blood cells, whereas the ascites tumor exposed to citric acid appeared normal.

Animals↗
PubMed1982

Refutation of the general single-locus model for the etiology of schizophrenia.

All published studies on the familial incidence of schizophrenia appropriate for testing the applicability of the general single-locus two-allele model are examined under the assumption of a unitary etiology for all schizophrenia. We show that the single major locus model is inadequate to predict the incidence in four classes of relatives of schizophrenic probands (parents, siblings, monozygotic, and dizygotic cotwins). In addition, the observed proportion of affected offspring from dual matings differ significantly from the model's prediction. The lack of an overall fit between the published familial distributions and the monogenic model suggests that a single major locus is insufficient for the etiology of schizophrenia. Further efforts in examining multifactorial models, mixed models, and other transmission models may be fruitful.

Chromosome Mapping↗
PubMed1981

Computed tomography in oral and maxillofacial surgery.

The use of computed tomography (CT) in oral and maxillofacial surgery is discussed. The CT scan delineates lesions in the oral and maxillofacial complex to aid in planning of surgical treatment. Case examples are presented, and the indications for the use of CT scanning are discussed.

Face↗
PubMed1980

Analysis of behavioral traits in the presence of cultural transmission and assortative mating: Applications to IQ and SES.

General linear models of familial resemblance are described which allow for polygenic inheritance, cultural transmission from parent to offspring, phenotypic assortative mating, common environment, and maternal and parental effects. These models use observed phenotypic correlations between multiple classes of relatives and/or correlations between individuals reared in separated and extended family structures to yield maximum likelihood parameter estimates. The models are first applied to American kinship data for IQ, with the variance of IQ partitioned as 30% additive genetic, 29% due to cultural inheritance, 9% due to gene--culture covariance, and 32% due to nontransmissible environment. Under the assumption that the correlations between (nontransmissible) environments of DZ and MZ twins are the same, an approximate treatment of dominance yields an estimate of 23% dominance variation.

Culture↗
PubMed1980

General causal models for sex differences in the familial transmission of multifactorial traits: an application to human spatial visualizing ability.

A general multifactorial model is given for the inheritance of traits that exhibit a sexual dimorphism. The model allows for polygenic inheritance, cultural transmission, phenotypic assortative mating, and a common environment of rearing. Several cultural mechanisms are described for which transmission from parent to offspring is sex-dependent and for which many different patterns of sex-specific correlations can result. A special case of the general model is described in which phenotypic differences between males and females are due only to differences in nontransmissible environmental factors and/or genetic factors that do not contribute to variability within a sex. Application of these models to human spatial visualizing ability, using data reported by others, gives an estimate of 45 per cent for the proportion of the variance that is accounted for by transmissible factors. Neither an X-linked hypothesis nor a sex-specific cultural mechanism is required to explain the transmission of spatial ability.

Female↗
PubMed1980

Posttraumatic acalculous cholecystitis.

Acalculous cholecystitis occurred in six patients after trauma and burns. The majority developed signs and symptoms similar to acute calculous cholecystitis. All were treated by cholecystectomy after traditional conservative treatment failed. All had either gangrenous changes or focal necrosis of the gallbladder. Postoperative recovery was uniform. Acalculous cholecystitis occurs in 0.5% of large series of injured or burned patients. Delayed recognition led to a high mortality, reported as 24% overall with 10% related to gallbladder disease. Although cholecystostomy has been advocated, it appears that cholecystectomy, when feasible, affords the best overall results.

Adult↗
PubMed1979

The use of multiple thresholds and segregation analysis in analyzing the phenotypic heterogeneity of multifactorial traits.

(1) Three models based on multifactorial inheritance are introduced to account for phenotypic heterogeneities. These models are used to determine whether subforms of a triat are: (a) different degrees of the same process, (b) non-familial environmental variants of the same process, and (c) independently transmitted processes. (2) The parameters of each model consist of two population prevalences and either one, two, or three correlation coefficients which reflect the three hypotheses given above. The models are formulated so that a likelihood ratio test may be performed to discriminate between them. (3) The following types of analyses are described: (a) analysis of prevalence data with separate population prevalence estimates, (b) analysis of prevalence data with the proband a parent with specified spouse, (c) analysis of prevalence data with the proband an offspring with specified parents, and (d) the full segregation distribution of families using Complex Segregation Analysis. (4) When compared with the Analysis of Prevalences, Complex Segregation Analysis has the following advantages: (a) the number of degrees of freedom for parameter estimates is greater and separate estimates of the population prevalences are not necessary, (b) standard errors of the parameters are smaller, and (c) the power to discriminate models is increased. (5) Phenotypic heterogeneities such as age of onset, severity, and sex effect can be more completely understood by the methods of analyses described above. The nosology of familial disorders can also be clarified, and environments relevant to the transmission of the trait can be detected. This approach is particularly suitable for the analysis for behavioural traits since it does not require the assumption that environmental effects common to relatives be ignored. (6) Finally, our experience indicates that incorporating both prevalence and pedigree data into a single analysis decreases the time required to perform the analysis.

Environment↗
PubMed1979

Pulmonary hypertension and sudden death in aortic stenosis.

Sudden death is now an infrequent occurrence in severe aortic stenosis. However, an impressive increase in pulmonary arteriolar resistance has been found in some patients with end-stage aortic stenosis dying suddenly or deteriorating suddenly after catheterisation. Pulmonary hypertension does not seem to cause sudden death, but, in conjunction with decreased cardiac output, a critical reduction in aortic orifice area, and left ventricular failure, pulmonary hypertension identifies a population at significant risk. The rare finding of severe pulmonary hypertension in aortic stenosis should be considered an important marker for sudden death and in association with left ventricular failure may indicate an urgent need for valve replacement, regardless of the apparent clinical condition of the patient. In a small number of subjects catheterised postoperatively, increased pulmonary arteriolar resistance lessened rapidly.

Aged↗
PubMed1979

Multifactorial inheritance with cultural transmission and assortative mating. II. a general model of combined polygenic and cultural inheritance.

A general linear model of combined polygenic-cultural inheritance is described. The model allows for phenotypic assortative mating, common environment, maternal and paternal effects, and genic-cultural correlation. General formulae for phenotypic correlation between family members in extended pedigrees are given for both primary and secondary assortative mating. A FORTRAN program BETA, available upon request, is used to provide maximum likelihood estimates of the parameters from reported correlations. American data about IQ and Burks' culture index are analyzed. Both cultural and genetic components of phenotypic variance are observed to make significant and substantial contributions to familial resemblance in IQ. The correlation between the environments of DZ twins is found to equal that of singleton sibs, not that of MZ twins. Burks' culture index is found to be an imperfect measure of midparent IQ rather than an index of home environment as previously assumed. Conditions under which the parameters of the model may be uniquely and precisely estimated are discussed. Interpretation of variance components in the presence of assortative mating and genic-cultural covariance is reviewed. A conservative, but robust, approach to the use of environmental indices is described.

Computers↗
PubMed1979

Multifactorial inheritance with cultural transmission and assortative mating. III. Family structure and the analysis of separation experiments.

Demographic data about family composition or structure in the United States is reviewed. About 25% of white children and a majority of black children are reared in either broken or extended families, and this must be taken into consideration for valid studies of cultural inheritance. Atypical family structures are described including those in which parents include: biological parents, stepparents, grandparents, uncles, aunts, sibs, foster parents, and their spouses. General formulae for a wide variety of kinship correlations are derived using path analysis. The multifactorial model presented allows for cultural inheritance, polygenic inheritance, correlated sibling environments, and phenotypic assortative mating (as previously described for intact families) plus extensions necessary for the analysis of separation experiments. These extensions allow for variable family structure and differences in parental influence due to separation, age or stage of development of the child, birth order, or type of relationship. Family structure is observed to have a marked effect on familial resemblance. Computer simulation studies demonstrate marked heterogeneity among phenotypic correlations for kinships of the same degree of genetic relationship arising in different family structures. Analyses of multiple types of sibs and other relatives in variable family structures offer great promise for the study of cultural inheritance.

Adolescent↗