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PubMed1988

Philosophy, medicine and its technologies.

There is a need to bring ethics and medical practice closer together, despite the risk and problems this may involve. Deontological ethics may promote sanctity of life considerations against the quality of life considerations favoured by consequentialists or utilitarians; while talk of respect for life and the value of life may point to more qualified ethical positions. This paper argues for a respect-for-life position, dismissing a utilitarian cost-benefit outlook as too simplistic; but an unqualified fixed principles approach is also ruled out, both because of its unacceptable consequences in individual cases and also because of its reliance on the slippery slope argument which, it is argued, is logically and psychologically deficient. The case of genetic engineering provides an example in which the notion of respect may operate, but in which broad general principles also apply. A cautious conservatism towards accepted principles is recommended in the development of medical technologies.

Aborted Fetus↗
PubMed1984

Sociological and psychological predictors of STD infection in homosexual men: a study of four countries.

I investigated over 600 homosexual men in four countries (Sweden, Finland, Ireland, and Australia) regarding the number of times they had contracted a sexually transmitted disease (STD) and several psychological variables including masculinity and feminity, sex role conservatism, relationships with parents, number of sexual partners, attitudes towards homosexuality, and involvement in the homosexual subculture. Using multiple linear regression in each country, it was found that 19-42% of the variance of number of times infected could be accounted for by psychosocial factors, seven of which were common to all countries. The number of sexual partners was not a significant variable in any country. These data strongly suggest that numbers of infections in homosexual men are best predicted by psychological factors, and this has considerable implications for preventative and treatment programmes for homosexuals.

Adult↗
PubMed1988

Differential rates of genic and chromosomal evolution in bats of the family Rhinolophidae.

Data for nondifferentially stained chromosomes from 10 species of Rhinolophus (Chiroptera: Rhinolophidae) suggest a conserved chromosomal evolution. G-banded chromosomes for three well differentiated species (Rhinolophus hipposideros, Rhinolophus blasii, and Rhinolophus acuminatus) corroborate a low level of gross chromosomal rearrangements. Additionally, a comparison between G-banded chromosomes of Rhinolophus (Rhinolophidae) and Hipposideros (Hipposideridae) suggests extreme conservatism in chromosomal arms between these two distantly related groups. On the other hand, we report extensive genic divergence as assayed by starch gel electrophoresis among these 10 species, and between Rhinolophus and two hipposiderid genera (Hipposideros and Aselliscus). The present chromosomal data are not sufficient for phylogenetic analysis. Phylogenies based on electrophoretic data are in many aspects discordant with those based on the classical morphological criteria. Different (and as yet not clearly understood) evolutionary forces affecting chromosomal, morphologic, and electrophoretic variation may be the reason for the apparent lack of concordance in these independent data sets.

Alleles↗
PubMed1979

Fibrous ureteral polyps.

Twelve cases of fibrous ureteral polyps are presented, illustrating their characteristic radiographic appearances. Two types--a long pedunculated mobile variety having a smooth surface, and a relatively shorter lesion covered with thin, finger-like projections--may be identified. Demonstration of the typical findings on excretory urography and/or retrograde ureterography establishes the diagnosis and permits surgical conservatism. Although no sex preponderance was noted, a wide sex-related age disparity was observed, the involved males being much younger than the females.

Adolescent↗
PubMed1984

Histiocytosis X: rate and pattern of resolution of osseous lesions.

Resolution rate and qualitative characteristics of healing were studied in 71 osseous lesions of histiocytosis X. Rates of healing, as assessed planimetrically and by vertebral body-height measurement, did not differ significantly among lesions that were treated with chemotherapy alone, chemotherapy plus radiation, radiation alone, or those that received no treatment. Lesions of Letterer-Siwe disease, Hand-Schuller-Christian disease, multiple eosinophilic granuloma, and solitary eosinophilic granuloma resolved at comparable rates. A trend toward more rapid healing was noted in younger children. Lesions treated with radiation alone showed a greater tendency to resolve with sclerosis, but radiographic healing characteristics did not strictly depend upon specific mode of therapy. These results support the concept of osseous histiocytosis X as a benign self-limited disorder when systemic disease is absent, and they encourage therapeutic conservatism.

Bone Diseases↗
PubMed2001

Species differences and similarities in the fine structure of the mammalian corpus callosum.

A cross-species ultrastructural study of the corpus callosum was performed in six domestic species: the rat, the rabbit, the cat, the dog, the horse and the cow. The results indicate cross-species conservatism in callosal fiber composition with a good interspecies relation between fiber number and brain size. Across species, increases in both brain size and callosal area indicate more callosal fibers, although less than expected from the estimated increase in cortical cell number. Within each species, the correlation between fiber number and brain weight tends to disappear, although in most cases a larger callosum implies a larger number of callosal fibers. The median fiber diameter was conservative across species (0.11-0.2 microm), indicating the maintenance of conduction velocity of most callosal fibers regardless of interhemispheric distance. Nevertheless, the maximal fiber diameters tended to be higher in species with larger brains. Therefore, there is a population of coarse-diameter fibers that tend to increase their diameter and conduction velocity with increasing brain size. However, allometric calculations suggest that the associated increase in velocity in these large fibers may not be sufficient to maintain a constant interhemispheric transmission time in different species.

Animals↗
PubMed2002

Improving the power of sib pair quantitative trait loci detection by phenotype winsorization.

OBJECTIVES: In sib pair studies, quantitative trait loci (QTL) identification may be adversely affected by non-normality in the phenotypic distribution, particularly when subjects falling in the tails of the distribution bias the trait mean or variance. We evaluated the robustness and power of reducing the influence of subjects with extreme phenotypic values by Winsorizing non-normal distributions in three versions of Haseman-Elston regression-based methods of QTL linkage analysis. METHODS: Data were simulated for normal and non-normal distributions. Phenotypic values that correspond to cutoff points at the omega and 1 - omega percentiles of the distribution were identified, and phenotypic values falling outside the boundaries of the omega and 1 - omega cutoff points were replaced by the omega and 1 - omega values, respectively. One million replications were performed for the three tests of linkage for Winsorized and non-Winsorized data. RESULTS: Winsorization reduced conservatism in the tails of the empirical type I error rate for the vast majority of the tests of linkage, increased the power of QTL detection in non-normal data and created a slight negative bias in symmetrical phenotypic distributions. CONCLUSIONS: Winsorizing can improve the power of QTL detection with certain non-normal distributions but can also introduce bias into the estimate of the QTL effect.

Genetic Predisposition to Disease↗
PubMed2002

The distribution and morphological characteristics of catecholaminergic cells in the brain of monotremes as revealed by tyrosine hydroxylase immunohistochemistry.

The present study describes the distribution and cellular morphology of catecholaminergic neurons in the CNS of two species of monotreme, the platypus (Ornithorhynchus anatinus) and the short-beaked echidna (Tachyglossus aculeatus). Tyrosine hydroxylase immunohistochemistry was used to visualize these neurons. The standard A1-A17, C1-C3 nomenclature was used for expediency, but the neuroanatomical names of the various nuclei have also been given. Monotremes exhibit catecholaminergic neurons in the diencephalon (A11, A12, A13, A14, A15), midbrain (A8, A9, A10), rostral rhombencephalon (A5, A6, A7), and medulla (A1, A2, C1, C2). The subdivisions of these neurons are in general agreement with those of other mammals, and indeed other amniotes. Apart from minor differences, those being a lack of A4, A3, and C3 groups, the catecholaminergic system of monotremes is very similar to that of other mammals. Catecholaminergic neurons outside these nuclei, such as those reported for other mammals, were not numerous with occasional cells observed in the striatum. It seems unlikely that differences in the sleep phenomenology of monotremes, as compared to other mammals, can be explained by these differences. The similarity of this system across mammalian and amniote species underlines the evolutionary conservatism of the catecholaminergic system.

Animals↗
PubMed1997

The evolution of insect flight: implications for the evolution of the nervous system.

The Insecta encompasses a prodigiously diverse group as measured at the species, family and ordinal levels, but the nervous system bears evidence of conservatism. The early acquisition of flight must have been a major factor in the diversification of body form. Arguments are presented that predator evasion was a primary factor in the origin of flight and that a conserved set of giant interneurons played a key element in the transition.

Animals↗
PubMed1988

The lateral-line and inner-ear afferents in larval and adult urodeles.

The inner-ear and lateral-line afferents were studied in members of almost all urodele families and in two primitive representatives of anurans and gymnophionans by means of transganglionically transported horseradish peroxidase. The lateral-line projection patterns are, when present, identical in all urodeles and gymnophionans. This is in agreement with the presence of ampullary organs in all urodeles and gymnophionans which possess a lateral-line neuromast system. In contrast, even the most primitive anurans lack both ampullary organs and the dorsal projection of afferents from these organs. In urodeles the inner-ear afferents are found to enter the rhombencephalon via the octaval nerve and bifurcate in the neuropil lateral to the nucleus magnocellularis into a short ascending and a longer descending subpial fascicle. Fibers of the ascending fascicle reach the tip of the lateral recess and terminate in the eminentia granularis. Collaterals are confined to the ipsilateral lobulus lateralis and end presumably as mossy fibers. The descending fascicle ends at the obex level with only a few fibers reaching the second spinal segment. Besides extensive fiber supply to the cells of the ipsilateral ventral-zone column, collaterals are found to reach the reticular formation, nucleus cerebelli, nucleus fasciculus solitarius, intermediate nucleus and several motor nuclei. Differences in the octaval projection among urodele families are limited to variation in its size relative to that of the lateral-line projection. Only species that develop without free-living larvae differ markedly with respect to the absence of lateral-line projections and, presumably, the lateral-line nuclei of the alar plate that exists in larvae. Almost all urodeles that possess a lateral-line system as larvae retain a complete lateral-line system, including neuromasts and ampullary organs, after metamorphosis. Only Salamandra and Chioglossa lose most of their lateral-line afferents and presumably all lateral-line organs around metamorphosis. The octavolateralis projections in urodeles are found to be strikingly similar to those in lampreys, sharks, sturgeons, and, especially, gymnophionans. This points to a great conservatism of this pattern, at least among anamniotic vertebrates. However, even primitive anurans such as Ascaphus differ markedly from these patterns in that they show no ampullary organs or dorsal lateral-line projection but a dorsal projection of the inner ear. Outgroup comparison with other anamniotic vertebrates indicates that the pattern in anurans is derived from the more generalized lateral-line and inner-ear projection pattern as represented in many urodeles and gymno

Amphibians↗
PubMed1975

The interrelationships of chromosome banding patterns in procyonids, viverrids, and felids.

The Giemsa banding patterns of the chromosomes of 4 species of Procyonidae, 13 of Viverridae, and 6 of Felidae have been studied. The patterns have all been related to the basic felid karyotype. Each procyonid and viverrid has a distinctive karyotype, whereas some felids have indistinguishable karyotypes even when banded. Extensive interfamilial G-banding conservatism has been demonstrated, with many chromosomes being "shared" by all three families. A chromosome identification and karyotyping system for the Carnivora has been devised to facilitate comparison of data from future studies. Phylogenetic implications of the findings have been discussed.

Animals↗
PubMed1980

Chromosomal interrelationship of hamster species of the genus Mesocricetus.

The similarity of chromosomes and the mode by which differences occurred in the chromosomes of the species comprising the genus Mesocricetus, M. auratus (2n = 44), two "cryptic" species of M. brandti (2n = 44 and 2n = 42) and M. newtoni (2n = 38) were determined. Most of the autosomes and the sex chromosomes have either complete or partial G-band correspondence and thus provide definitive evidence for the taxonomic relationship of these species. The karyotypic differences occurred primarily as a result of deletion of sex chromosome heterochromatin and of autosomal translocations that frequently involved chromosomes with heterochromatic short arms or chromosomes bearing NOR's. Only one Robertsonian centric fusion occurred. Despite the conservatism of arrangement of the genetic material, the chromosomal distribution of heterochromatin diverged during the evolution of these species. M. brandti and newtoni each have a metacentric chromosome with a common long arm matching a submetacentric M. auratus autosome, but a short arm corresponding to two different M. auratus chromosomes. These translocations are crucial for explaining the direction of chromosomal evolution of these species and indicate that M. auratus was the commmon ancestral species and that M. brandti and newtoni subsequently evolved independently.

Animals↗
PubMed1980

Comparative chromosome studies in the family Leporidae (Lagomorpha, Mammalia).

Chromosome banding patterns of Lepus saxatilis, 2n = 48, and Pronolagus rupestris, 2n = 42, are presented. Comparison of G-banded karyotypes allows the identification of similar elements in both species. The karyotype of P. rupestris differs from that of L. saxatilis by the presence of three fusions in the former. Comparative studies with the fusion products of Oryctolagus cuniculus indicate that fusion and not fission is the major factor in chromosomal evolution of these leporids. The chromosomal conservatism of the hares is compared to the karyotypic variability of the rabbits and possible causes are discussed.

Animals↗
PubMed1982

The interrelationships of chromosome banding patterns in canids, mustelids, hyena, and felids.

The G-banding patterns of six canids, four mustelids, one hyena, and 12 felids have been studied, and data from the study of 30 felids are summarized. The canids are karyotypically very similar to one another, but minor differences have tentatively been identified. The mustelids show the greatest karyotypic diversity of all the carnivore families so far studied. They do display, however, considerable G-band conservatism, as is common throughout the Order, and appear karyotypically more closely related to the Feloidea than to the Canoidea. The hyena shares many autosomes with the felids, showing a close relationship to that family. The felids are for the first time divisible into small groups or individually identifiable on the basis of 16 different karyotypic patterns.

Animals↗
PubMed1996

Karyotypic patterns of seven species of molossid bats (Molossidae, Chiroptera)

G- and C-banding patterns of seven species of the bat family Molossidae, Eumops glaucinus, E. perotis, Molossops abrasus, M. temminckii, Molossus ater, M. molossus, and Nyctinomops laticaudatus, were identified. Comparisons among the karyotypes of these species showed extensive homologies between E. perotis, M. ater, M. molossus, M. abrasus, and N. laticaudatus, demonstrating inter- and intrageneric conservatism, and a lesser degree of homologies in M. temminckii and E. glaucinus, reflecting intrageneric variation. Chromosomal variation was due to inversions, Robertsonian rearrangements, translocations, and variations in the location of constitutive heterochromatin and nucleolus organizer regions. The chromosome corresponding to No. 5 in the M. ater karyotype is discussed. We suggest that the Nyctinomops and Molossops karyotypes represent the primitive condition and that Molossus and Eumops have derived karyotypes.

Animals↗
PubMed1977

Amino acid sequence homology and the vitamin K-dependent proteins.

Examination of amino acid sequence data on bovine vitamin K-dependent clotting zymogens, using the Gibbs and McIntyre diagonal plot, leads to the conclusion that they are homologous and have evolved by a series of gene duplications. Plasminogen is also homologous but lacks the region containing glutamic acid (Glu) residues gamma-carboxylated in a vitamin K-dependent step. Both prothrombin and plasminogen show internal sequence homology resulting from partial gene duplication and quintuplication respectively; each internal homology loop in prothrombin shows significant homology with each of the five putative loops in plasminogen. Recently, Walz et al. (Proc. natn. Acad. Sci. USA 74: 1969-1972, 1977) have sequenced the non-thrombin region of human prothrombin (residues 1-273) and this has enabled identification of regions conserved in 90 million years of eutherian evolution. The relative conservatism of homology loop 1 (bovine residues 66-144) which has no known function is discussed 'gamma-Carboxyglutamic acid; (Gla) has been found in proteins unrelated to the plasma clotting factors; a bovine bone-matrix protein('osteocalcin') has been sequenced by Price et al. (Proc. natn. Acad Sci. USA 73: 3373-3375, 1976) but it shows no homology with prothrombin or factor X.

Amino Acid Sequence↗
PubMed1976

Disaster at Buffalo Creek. Family and character change at Buffalo Creek.

Psychiatric evaluation teams used observations of family interaction and psychoanalytically oriented individual interviews to study the psychological aftereffects of the 1972 Buffalo Creek disaster, a tidal wave of sludge and black water released by the collapse of a slag waste dam. Traumatic neurotic reactions were found in 80% of the survivors. Underlying the clinical picture were unresolved grief, survivor shame, and feelings of impotent rage and hopelessness. These clinical findings had persisted for the two years since the flood, and a definite symptom complex labeled the "Buffalo Creek syndrome" was pervasive. The methods used by the survivors to cope with the overwhelming impact of the disaster--first-order defenses, undoing, psychological conservatism, and dehumanization--actually preserved their symptoms and caused disabling character changes.

Character↗
PubMed1995

The decision to remove homosexuality from the DSM: twenty years later.

Twenty years have passed since the American Psychiatric Association (APA) voted, in 1973, to remove "Ego-syntonic Homosexuality" from the Diagnostic and Statistical Manual of Mental Disorders (DSM). The present study investigates the influence of the patient's sexual orientation on the therapist's perception of the former's mental health. Four hundred and seventeen Israeli therapists (psychiatrists, clinical psychologists, and social workers) participated in the study, representing a cross-section of professionals in the mental health services in Israel. The measures included a demographic questionnaire and a perceived-severity scale of rating. Participants were assigned case histories where a hypothetical patient was heterosexual or ego-syntonic homosexual. Attributions of severity of mental status were found to differ as a function of sexual orientation of patient. Results are discussed in terms of the latent function of psychotherapy, considering the contrast between the liberal political attitudes and the secular way of life of the therapists on the one hand and their conservatism in the clinical domain on the other hand.

Adult↗