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[Genetic counseling in neurofibromatosis. Apropos of a study of 53 families].

Referring to a retrospective study of 53 families affected with neurofibromatosis and seen in genetic consultation from January 1977 to September 1987, the authors emphasize the difficulties of genetic counselling in this disease due to its variable expressivity with unforeseeable natural evolution and to the difficulty in detecting minor forms without biological markers. These results confirm previous studies (Carey 1979, Riccardi 1981): About half the cases are relevant to a neomutation and in these sporadic cases, the average paternal age is significantly increased (36.7 years). In familial cases, an intrafamilial variable expressivity is noted in 63.3% of families and no maternal effect is found. The penetrance of the disease, calculated from the familial cases, is estimated to 97% which confirmed the anterior data. The severe forms rate (grades III and IV) is about the same for familial cases, than in previous publications, but is higher for sporadic cases than the proportion described by Riccardi (25 to 30%) probably because of an ascertainment bias. Finally, If the risk for the offspring of an affected patient can be estimated at 1/2, however it is impossible to predict the severity of the disease. Before concluding to a neomutation (1st child of a couple) or to an absence of genetic risk (non affected person related to a familial case), a minor form must be searched by a careful physical examination, although the recent localization of the gene allows us to think of molecular biology for familial studies in a near future.

Female↗

[Computerized management in the surveillance of nosocomial infections].

A personal computerised system was developed for the on-going assessment and monitoring of hospital infections. The system involves the computer processing of clinical analyses. It also selects and statistically processes the data from microbiological tests conducted on hospital patients and staff. The system makes it possible to monitor the microbiological situation of the hospital environment with particular reference to the air, surfaces, instruments and material. In this way it is possible to identify the outbreak of minor hospital epidemics and to monitor their evolution and spread.

Air Microbiology↗

Kinking of the internal carotid artery: clinical significance and surgical management.

The authors report on 62 surgical corrections for kinking of the internal carotid artery during a 13-year period (1980-1993). This represents 2.8% of all carotid operative procedures (n = 2188) in the same period. It always concerned a significant (< 60 degrees) angulation of a redundant internal carotid artery, that in all but 3 cases was associated with atherosclerotic involvement of the carotid bifurcation. The indication to surgery included transient hemispheric or ocular ischaemia in 25.5% of cases, a regressive neurologic deficit in 8%, a minor stroke in 3%, a stroke in evolution in 11%, and non-lateralized cerebral ischaemia in 21%. In 19 patients (31%) it concerned an asymptomatic high degree stenosis. The surgical technique consisted in carotid transposition-reimplantation after eversion endarterectomy in 37 cases, in posterior transverse plication with patch angioplasty in 20 cases, and in segmental excision with venous interposition graft in 5 cases. There was one postoperative death. The morbidity include one ipsilateral non-fatal stroke and 3 transient ischaemic attacks. A complete long-term follow-up (mean duration 3.4 years) is available for 57 patients. The late incidence of stroke is 1.5% per year. The 5-year survival attains 67%. These long-term results are comparable to the outcome of standard endarterectomy in the same institution. The authors discuss the indication, techniques, and outcome of surgical correction of kinked internal carotid artery. They recommend a shortening procedure, often associated with endarterectomy for severely kinked vessels (angulation 60 degrees or less), symptomatic or not.

Aged↗

Changing perspectives in the diagnosis of peripheral vascular trauma.

The diagnosis of peripheral vascular trauma has undergone significant evolution in the last two decades. A minority of patients with arterial trauma present with classic findings that make the diagnosis obvious. However, the diagnosis of occult arterial injuries is more challenging, and it is for this group that the diagnostic algorithm has changed most significantly. Because of the low yield of routine operative exploration and routine arteriography to evaluate potential injury to vessels in proximity to penetrating wounds, many authors now recommend the selective use of arteriography or other diagnostic modalities based on the results of clinical examination and noninvasive pressure determinations. This article reviews the evidence in support of such a selective approach to the diagnosis of arterial injuries.

Algorithms↗

Monoalleleic transcription of the insulin-like growth factor-II gene (Igf2) in chick embryos.

A polymorphism in the igf2 gene of chickens was identified using NlaIII (GenBank accession number AF218827). In some embryos, the igf2 alleles were expressed monoallelically from either maternal or paternal alleles. These data demonstrate that genomic imprinting is not confined to mammalian vertebrates and suggest that genomic imprinting evolved at an early stage of vertebrate evolution. The observations that the igf2 gene is imprinted in a minority of embryos suggest that the imprinting in birds is unrelated to embryonic growth. Genome imprinting may provide opportunities for evolution of genes in a nonexpressed state. In poultry breeding, the presence of imprinted genes may make a major contribution to unequal performance in reciprocal matings between commercial lines.

Alleles↗

Origin of serum hepatitis B virus in acute exacerbation: comparison with HBV in the liver and from other exacerbation.

Acute exacerbation (AE) of chronic hepatitis B is usually preceded by reemergence or increase of hepatitis B virus (HBV) in the serum. To investigate the origin of the reemergence or increase, we compared the identity of the serum viral genome to that in the liver and in previous AE by full-length sequencing. The full-length viral genome and extent of quasispecies were obtained from serum and liver biopsy specimens at the same time from 9 subjects with hepatitis B exacerbation (group I). Composition of viral quasispecies was compared by the genetic diversity and the average number of nucleotide substitutions within and between different viral sources. Another 2 patients with repeated AEs (group II) were also enrolled, and their serial serum alanine aminotransferase, HBV DNA levels and full-length sequences were determined. In all group I patients, serum viral genome was identical to that in the liver. The genetic diversity and the average number of nucleotide difference were also comparable between serum and liver tissue. In 2 group II patients, the viral variant that emerged after previous AE was not identical to that caused by the subsequent AE. Dominant viral strains for serial AEs in a single patient did not show a sequential evolution, but presented as a horizontal selection of a minor population from the original viral pool. In conclusion, the findings suggest that viral strain in serum reflects the intrahepatic strain of the AE. Random reactivation of the original HBV pool, rather than a sequential evolution of one strain, also contributes to the onset of repeated AE. Supplementary material for this article can be found on the HEPATOLOGY website (http://interscience.wiley.com/jpages/0270-9139/suppmat/index.html).

Acute Disease↗

Ewing tumours and synovial sarcomas have critical features of karyotype evolution in common with epithelial tumours.

We have analysed the accumulated cytogenetic data on karyotypic evolution in Ewing tumours (ET) and synovial sarcomas (SS). Both tumour types frequently show balanced translocations, t(11;22) and t(X;18), respectively, that result in specific fusion genes. The analyses revealed +8, +12, +1q, and 16q- as important secondary changes to t(11;22) in ET and the imbalances showed a distinct temporal order. By principal component analysis, one major karyotypic pathway dominated by gains and one minor dominated by losses were identified. The kartyotypic evolution pattern in SS was less distinct. Both ET and SS showed a power law distribution of the number of acquired aberrations, which in both tumour types conformed to a distribution with an exponent equal to 1. Similar distributions are frequently found in epithelial tumours. ET and SS differ in this respect from other malignancies with balanced translocations resulting in fusion genes, which typically show a power law distribution of the number of acquired aberrations with exponents close to 2. This suggests that chromosome changes in ET and SS may develop through mechanisms more similar to those in epithelial tumours lacking recurrent balanced rearrangements than in haematological malignancies characterised by balanced translocations leading to fusion genes.

Bone Neoplasms↗

Accelerated atherosclerosis in subjects with some minor deviations from the common type of distribution of human coronary arteries.

Gross dissection of the coronary arteries of 566 subjects aged 0--45 years from an unselected population sample of Bucharest revealed the presence of a similar anatomical branching pattern in 58% of cases. Starting from this common type of distribution of coronary arteries, some minor deviations were detected coexisting with a thicker intima, a more rapid onset and evolution of atherosclerotic plaques, and a more important degree of luminal obstruction. Among the 15 minor deviations described in this paper, 3 were constantly associated, 9 only occasionally associated and 3 not associated with an accelerated atherosclerosis. The most important of these atherogenic deviations was present in 29% of cases or in 1 out of every 3 or 4 subjects. In essence, these deviations consisted of an excessive increase in external diameter and length of the left coronary arterial system, coexisting with an underdeveloped right coronary arterial system, or vice versa. The atherogenic deviations from the common type of distribution of the coronary arteries seemed to represent an important genetically transmitted risk factor for coronary heart disease.

Adolescent↗

The effect of foot orthoses in rheumatoid arthritis.

OBJECTIVE: To evaluate the effectiveness of foot orthoses using the foot function index (FFI) in a group of patients with rheumatoid arthritis (RA) during a period of 6 months. METHODS: Thirty-six rheumatoid subjects with foot pain were examined and appropriate foot orthoses were prescribed according to each patient's needs. All the patients were evaluated 30, 90 and 180 days after the baseline visit. FFI values, daily time of wearing the orthoses and adverse effects were noted at each appointment. The Stanford Health Assessment Questionnaire (HAQ) was used at the initial visit to evaluate the influence of physical condition on FFI response. RESULTS: With the use of foot orthoses, FFI values decreased in all subscales (pain, disability and activity limitation). This reduction was noted in the first month and was maintained throughout the trial. Those using EVA (ethyl-vinyl acetate; n = 28) orthoses presented results similar to those for the total group. Patients wearing made-to-measure orthoses (n = 8) exhibited higher initial FFI values and worse evolution during the trial, significant for pain and disability but not for activity limitation. Minor adverse reactions were noted; none required interruption of treatment. There was no relation between HAQ and FFI evolution. CONCLUSIONS: Foot orthoses were effective as an adjuvant in the management of rheumatoid foot. They significantly reduced pain, disability and activity limitation, as measured by the FFI, with minor adverse effects.

Activities of Daily Living↗

Bony ponticles of the atlas (C1) over the groove for the vertebral artery in humans and primates: polymorphism and evolutionary trends.

The aim of this study was to ascertain the distribution in primates of the three possible bony ponticles over the groove for the vertebral artery (ventral, lateral, and dorsal ponticles), in order to attempt to understand the variants observed in humans and to ascertain possible evolutionary trends in primates. The material consisted of 393 atlases of extant nonhuman primates representative of 41 genera, and of 500 human atlases (dried bones of adults). For each atlas, we studied the existence and morphology of the ponticles, and the type of association of these three ponticles on a given side, which are theoretically of eight in number (types A-H). The occurrence of these ponticles varied from complete absence to constant presence, according to the genera and taxa of primates. The presence of each of these ponticles in primates can be interpreted as a primitive or plesiomorphic character, and their absence as a derived or apomorphic character. The strepsirhines-platyrrhines-cercopithecines group, presenting a predominant primitive pattern (type A), appeared to be separated from the colobines-hominoids group, presenting predominant derived patterns (type C in colobines, Pongo pygmaeus, and Pan troglodytes, and the more derived type D in Hylobates, Gorilla gorilla, and Homo sapiens). The last derived stage, corresponding to the disappearance of the three atlantal ponticles (type H), was only observed in some individuals in hominoids. A marked intraspecific polymorphism characterized the hominoids. The presence of lateral and dorsal ponticles in humans appeared to correspond to their persistence within the progressive disappearance of the atlantal ponticles, constituting an evolutionary tendency characteristic of primates and particularly of hominoid evolution.

Animals↗

X-ray microanalytical study of Mn and Fe compartmentation in maize chloroplasts.

X-ray microanalysis of mesophyll and bundle sheath maize chloroplasts showed that bound manganese is located within thylakoids, whereas bound iron is equally present in thylakoids and stroma. A simple correlation between manganese content and oxygen evolution capacity (Photosystem II activity) is unlikely since Mn is also present in bundle sheath thylakoids of low Photosystem II activity. A major part of manganese has probably a distinct function and only a minor part plays a role in the process of oxygen evolution.

Chloroplasts↗

The cytogenetic scenario of chronic myeloid leukemia.

The Philadelphia chromosome (Ph), i.e., the reciprocal translocation t(9;22)(q34;q11), is found with great specificity in bone marrow cells from patients with chronic myeloid leukemia (CML). Variant Ph-producing translocations, seen in 5-10% of all patients, are all complex and involve the same molecular rearrangement as the regular t(9;22). Patients with classic and variant Ph-producing translocations are clinically and hematologically identical, and as a group differ from Ph-negative CML patients. In all patient groups, the occurrence of additional chromosome changes is an ominous sign indicating that disease progression is imminent. The chromosome changes occurring in excess of the Ph in CML are clearly nonrandom and two pathways of cytogenetic evolution may be distinguished. Major route changes comprise trisomy 8, i(17q), trisomy 19, and an extra Ph; totally, 71% of Ph-positive CML patients have at least one of these four major route changes. Six minor route changes, including five numerical abnormalities (-7, -17, +17, +21, and -Y) but also one structural aberration, t(3;21) (q26;q22), have been identified. At least one of these changes is found in 15% of all Ph-positive CML cases. Altogether, the four major route aberrations and the six minor route changes are present as part of the clonal evolution in 86% of CML with cytogenetic abnormalities in addition to the Ph chromosome.

Blast Crisis↗

Chromosomal rearrangement in pectinidae revealed by rRNA loci and implications for bivalve evolution.

Karyotype and chromosomal localization of major (18-5.8-28S) and minor (5S) ribosomal RNA genes were studied in two species of Pectinidae, zhikong (Chlamys farreri) and bay (Argopecten irradians irradians) scallops, using fluorescence in situ hybridization (FISH). C. farreri had a haploid number of 19 with a karyotype of 3m + 4sm + 7sm-st + 4st + 1st-t, and A. i. irradians had a haploid number of 16 with a karyotype of 5st + 11t. In C. farreri, the major and minor rRNA genes had one locus each and were mapped to the same chromosome-Chromosome 5. In A. i. irradians, the major rRNA genes had two loci, located on Chromosomes 4 and 8, and the 5S rRNA gene was found at a third chromosome-Chromosome 10. Results of this and other studies indicate that karyotype of A. i. irradians (n = 16, 21 arms) is secondary and derived from an ancestral karyotype similar to that of C. farreri (n = 19, 38 arms) through considerable chromosomal loss and rearrangements. The ability to tolerate significant chromosomal loss suggests that the modal karyotype of Pectinidae and possibly other bivalves with a haploid number of 19 is likely tetraploid; i.e., at least one genome duplication has occurred during the evolution of Bivalvia.

Animals↗

Spectrum of CLN6 mutations in variant late infantile neuronal ceroid lipofuscinosis.

The neuronal ceroid lipofuscinoses (NCLs) are a group of autosomal recessive neurodegenerative diseases of childhood. CLN6, the gene mutated in variant late infantile NCL (vLINCL), was recently cloned. We report the identification of eight further mutations in CLN6 making a total of 18 reported mutations. These mutations include missense, nonsense, small deletions or insertions, and two splice-site mutations. Ten mutations affect single amino acids, all of which are conserved across vertebrate species. Minor differences in the pattern of disease symptom evolution can be identified. One patient with a more protracted disease progression was a compound heterozygote for a missense mutation and an unidentified mutation. Fifteen CLN6 mutations occur in one or two families only, and families from the same country do not all share the same mutation. Unlike NCLs caused by mutations in CLN1, CLN3, CLN5, and CLN8, there is no major founder mutation in CLN6. However, one mutation (E72X) is significantly more common in patients from Costa Rica than two other mutations present in that same population. In addition, a 1-bp insertion (c.316insC) is associated with families from Pakistan and I154del may be common in Portugal. A group of Roma Gypsy families from the Czech Republic share two disease-associated haplotypes, one of which is also present in a Pakistani family, consistent with the proposed migration of the Roma from the Indian subcontinent 1,000 years ago. All mutations are recorded in the NCL Mutation Database together with their country of origin for use in the development of rapid screening assays to confirm diagnosis and to facilitate carrier testing appropriate to a population.

Age of Onset↗

Near-infrared spectroscopy of dark asteroids.

Near-infrared (J, H and K bands) spectra of nine dark asteroids (chosen among a sample of supposed primitive objects between C and D classes) have been obtained at the Mauna Kea Observatory (Hawaii) with the 2.2-m telescope using KSPEC as spectrograph. The aim of this work was to search for evidence of the presence of organic materials in these objects as found in other planetary bodies as 5145 Pholus, and in some cometary nuclei. A careful analysis of the data has revealed flat or slightly redder spectra than the solar one for all observed asteroids. No evidence of distinct absorption features was found.

Astronomy↗

Skeletal segments of the human pollical and hallucal rays: comparison and analysis of their intrinsic proportions.

Since in humans, the first digital ray has a different functional significance in the hand and in the foot, the comparison of the pollical and hallucal rays seems interesting in order to evaluate the influence of specific evolutionary functional factors and biomechanical constraints. The objective of this study was to provide original and detailed data on the intrinsic proportions of the three segments of the human pollical and hallucal rays (metacarpal or metatarsal bone, proximal phalanx, and distal phalanx) in order to allow a quantitative comparison of their relative development. No similar data evaluated from three-dimensional approaches (volumetric or ponderal) seem to be available in the literature. The material consisted of 77 skeletons of the pollical ray and 77 skeletons of the hallucal ray of normal adult individuals. The ponderal approach was used. The first metapodial represented a mean of 57.17% for the pollical ray and 68.48% for the hallucal ray, whereas the phalanges respectively represented 42.83% and 31.52%. The intrinsic phalangeal proportions were almost identical for the pollex and for the hallux (respectively, 71.76% and 72.88% for the proximal phalanx; and 28.24% and 27.12% for the distal phalanx). Since these intrinsic proportions are the reflection of biological, functional and evolutionary constraints, these data seem of interest for the analysis of the functional significance of these rays, for the characterization of malformative syndromes in clinical practice, for reference in comparative morphology, and for the interpretation of hominid fossil bones.

Biological Evolution↗

Sudden extinction of the dinosaurs: latest Cretaceous, upper Great Plains, USA.

Results of a three-year field study of family-level patterns of ecological diversity of dinosaurs in the Hell Creek Formation of Montana and North Dakota show no evidence (probability P < 0.05) of a gradual decline of dinosaurs at the end of the Cretaceous. Stratigraphic reliability was maintained through a tripartite division of the Hell Creek, and preservational biases were corrected for by comparison of results only from similar fades as well as through the use of large-scale, statistically rigorous survey and collection procedures. The findings are in agreement with an abrupt extinction event such as one caused by an asteroid impact.

Animals↗