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PubMed1987

Radical treatment of craniofacial anomalies in infancy and the use of miniplates in craniofacial surgery.

The radical treatment of craniofacial anomalies in infancy is indicated for medical, technical, and psychosocial reasons. The major problems around the cranium, the orbits, and the face may be safely corrected by osteotomy, suture resection and disjunction, mobilization, repositioning, and reshaping of the various skeletal segments. This radical approach has been possible through the introduction of miniplate fixation. The plates and screws are removed after 3 to 6 months to take optimal advantage of the great formative power of the growing brain, which expands rapidly within the first 2 years of life. In infants, disjunction is more important than advancement, making this approach a dynamic one in contrast with the static procedures for the adolescents and adults. The complete, one-stage procedures are superior to a delayed or two-stage procedure. Experienced administration of pediatric anaesthesia and intensive care are mandatory.

Acrocephalosyndactylia↗

PubMed1985

[Evaluation of perioperative cefoxitin in the prevention of infectious complications of surgery in cancer of the upper respiratory-digestive tracts].

Twenty-three patients (22 male and 1 female) aged 41 to 70 years (mean age 56.4 years) with cancer of the upper respiratory and digestive tracts were entered into the study prior to a major surgical procedure involving incision of cervical mucous membranes. Participants were randomly assigned either to a control group (10 patients) which received no routine intra or postoperative antibiotics, or to a treatment group (13 patients) given cefoxitin perioperatively. Treated patients were given 30 mg/kg cefoxitin intravenously over 30 mn, one hour before surgery was begun, and 30 mg/kg over one hour, 3 hours and 6 hours after the initial infusion was started. Rate of local infection was 80% (8/10) and 15% (2/10) in the control group and treated group respectively (p less than 0.001). In addition, a significant difference in rates of local complications was found: 7 disjunctions and/or fistulae or pharyngostomes in the control group against one suppuration with disjunction in the treated group. In the treated group, a mean 24.6 day reduction in time lapse to cicatrization was observed. Fever greater than or equal to 39 degrees C occurring or persisting beyond the 48th postoperative hour was also significantly more frequent in the control group (7/10 versus 3/13). In contrast, no significant difference was found between rates of other infectious localizations. Local bacterial flora recovered in both groups before and/or after surgery was unremarkable and prophylactic cefoxitin selected no particular pathogens.

Adult↗

PubMed1984

Sterile mutants in Caenorhabditis elegans: the synaptonemal complex as an indicator of the stage-specific effect of the mutation.

Two sterile mutants of Caenorhabditis elegans hermaphrodites have been examined using the electron microscope and serial section analysis. The F4 and F80 mutants were described previously ( Mounier and Brun , 1980), and they were shown to be blocked at the start of oogenesis. In the F4 mutant, normal sperm are produced and the pachytene nuclei contain tripartite synaptonemal complexes (SC) between the homologously paired chromosomes. In the F80 asynaptic mutant, only a few sperm are produced and they have abnormal morphology. Whereas SCs and SC associated structures (termed 'SC knobs') are present in the F4, these structures are absent from the F80 . The mutation in F80 affects gametogenesis prior to the pachytene stage of meiosis and pairing of homologous chromosomes apparently does not occur. The SC knobs may influence the regulation of the disjunction of the chromosomes. For that reason, these structures are now termed 'disjunction regulator regions'.

Animals↗

PubMed1981

[Effect of the dynamic factors of space flight on the mutagenic effect of radiation. II. Development of recessive lethals and loss of X-chromosomes in Drosophila melanogaster oocytes].

The modifying effect of dynamic space-flight factors on radiation damage of Drosophila oocytes was measured by the frequencies of X-chromosomal non-disjunction, loss and sex-linked recessive lethals. It has been shown that with a slight increase in the non-disjunction frequency, dynamic factors did not influence the frequency of loss events in irradiated oocytes. The yield of recessive lethal mutations increased in irradiated oocytes-7 both upon pre- and postradiation action of dynamic factors. A similar increase in the frequency of recessive lethals was observed after an additional action of acceleration on irradiated oocytes. It is assumed that the modifying effect of dynamic factors is associated with repair repression at early stages of radiation damage.

Acceleration↗

PubMed1980

Stimulus-rule interactions in concept verification.

The difficulty of learning a conceptual rule has been shown to depend upon the stimulus attributes which that rule conjoins. For what appear to be separable attributes, the disjunctive rule is easier than the conjunctive. In contrast, for what appear to be integrable attributes, the conjunctive rule is easier. This paper reports six experiments designed to determine whether the integrality of stimulus attributes affects the speed of verification of the stimulus, as positive or negative, with respect to a given conjunctive or disjunctive concept. The pattern of reaction times is not consistent with the result of rule-learning experiments and does not support an integrality hypothesis. Verification times seem to be more a function of the perceptual salience of the relevant attributes of the concept. Thus, a perceptual-integrality hypothesis is an unlikely explanation of rule learning results.

Color Perception↗

PubMed1995

[Terminalization of chiasmata. Analysis of the phenomenon].

On the basis of my own and published data, a conclusion was made that meiotic terminalization of chiasmata, which was postulated by Darlington, does not occur. The chiasmata remain in the sites where they appear, until the disjunction of homologous chromosomes in meiotic anaphase I. The disjunction of homologues is accounted for by repulsion of the sister chromatids.

Chromosomes↗

PubMedDate not supplied

[A comparison of the characteristics of chromosome nondisjunction in the first maturation division of mouse oocytes heterozygous for balanced structural rearrangements of the chromosomes].

Peculiarities of non-disjunction of chromosomes in the first meiosis of maturation of oocytes in mice heterozygous in the Robertsonian and nonuniform reciprocal translocations have been determined. Mice, heterozygous in one Robertson's translocation, had general frequency of chromosomal non-disjunction in the 1st meiosis of oocyte maturation equal to 17%; by two Robertsonian translocations the total frequency of genetically deficient oocytes amounted to about 77%, in case of unequal reciprocal translocation--to 50%. In two latter cases genetic disturbances were due to unbalanced euploid chromosome sets.

Animals↗

PubMed1975

[Mutagenic action of static electric fields on Drosophila melanogaster females].

The effect of the 24-hours' action of 1500 v/cm and 3300 v/cm static electric fields (SEF) on the non-disjunction and sex-linked recessive lethal mutations in Drosophila melanogaster females was studied. Both SEFs increased the frequency of sex-linked recessive lethals, that was shown to be independent of the boltage of the field. The action of SEF exerted on effect on the frequency of non-disjunction of X-chromosomes.

Animals↗

PubMed1994

Issues in the assessment of nutritional status using anthropometry.

Four issues in the use and interpretation of anthropometry are discussed at the level of the population and of the individual. The first issue is the index or indices of choice: weight-for-height versus height-for-age versus weight-for-age. The selection of an index or indices depends upon many factors, and no one index is completely adequate in all situations. Proposed criteria are provided to assess the severity of low anthropometry within populations. The second issue is the scale of the index: z-scores (or standard deviations) versus percentiles versus percent-of-median. z-Scores have several properties that make them superior to the other two scales. A third issue deals with limitations in the current growth reference; one of these is the disjunction between the growth curves at 2 years of age, resulting from the use of two different populations in the reference. It is important that this disjunction be recognized by researchers so that the anthropometric findings are interpreted correctly for this age range. Lastly, some issues to do with the collection of single versus multiple anthropometric measurements on children are discussed.

Anthropometry↗

PubMed1993

Should all pregnant patients be offered prenatal diagnosis regardless of age?

OBJECTIVE: To assess the acceptance of prenatal genetic diagnosis by patients younger than 35 years old who are therefore not yet at great risk for non-disjunction trisomies based on maternal age. METHODS: The patients were counseled regarding the following: 1) the age-related risk of chromosomal abnormalities, 2) the procedure-related risk of fetal loss, 3) clinical implications of chromosomal abnormalities, 4) the need for complete counseling by a certified genetic counselor, and 5) the patient expense of $600-1200 if third-party reimbursement was not available. Patients were recruited from the private practice of the senior author at the New York Hospital--Cornell Medical Center. Five hundred ninety-one patients were offered prenatal genetic diagnosis. The outcome measure was the patient's decision to undergo prenatal diagnosis even though the risk of a non-disjunction trisomy was expected to be low based on maternal age. Amniocentesis was performed in 128 patients and chorionic villus sampling in five. RESULTS: One hundred thirty-three patients (22.5%) chose prenatal diagnosis. Karyotype was obtained in 131 procedures, but two were unsuccessful. One of the 131 karyotypes was abnormal and the patient chose to terminate the pregnancy. CONCLUSIONS: The data showed the following: 1) Inappropriate influence of patients by the health provider was not evident; 2) routine offering of genetic diagnosis enhanced the autonomy of pregnant women; 3) the potential increase in the loss of pregnancies that accompanies this practice is ethically justified; and 4) there are no compelling cost-benefit objections to such a practice.

Adolescent↗

PubMed1996

Non-mosaic trisomy 16 in a third-trimester fetus.

BACKGROUND: Trisomy 16 in the most common trisomy first-trimester spontaneous abortions, suggesting a high rate of non-disjunction of this chromosome. Deoxyribonucleic acid studies in aborted conceptuses with trisomy 16 have demonstrated a maternal origin in all cases. There have been cases of confined placental mosaicism, fetal mosaicism, and partial trisomy involving chromosome 16 reported in term fetuses. However, to our knowledge, there have been no previous reports of a near-term fetus with full trisomy 16 since the advent of modern chromosomal banding techniques. CASE: A 25-year-old Filipino woman underwent obstetric sonographic evaluation at 32 weeks' gestation; results were remarkable for oligohydramnios, severe growth restriction, and multiple dysmorphic features. Percutaneous umbilical blood sampling was performed for rapid karyotyping, viral serology, and blood profiles. The fetal karyotype was 47, XY+16; the remainder of the laboratory analysis was unremarkable. The patient went into spontaneous labor at 35 weeks' gestation and delivered a stillborn female fetus (birth weight 783 g). Chromosomes from skin, brain, and chorionic villi were examined and all demonstrated trisomy 16 (47, XX,+16). Deoxyribonucleic acid primers for known polymorphic regions of chromosome 16 were used and determined the origin of the extra chromosome to be non-disjunction during paternal meiosis. CONCLUSION: Previously, full trisomy 16 has been thought to be incompatible with fetal survival past the early second trimester. This case also contrasts with previously reported experience with trisomy 16 in that parental origin studies determined that the extra chromosome 16 originated from the father, suggesting that paternal derivation of the additional chromosome may play a role in the ultimate phenotypic expression.

Adult↗

PubMed1997

[Movement and behavioral disorders in anterior cerebral artery territory infarction].

Anterior cerebral artery territory infarction, which affects the medial frontal lobe and anterior part of the corpus callosum, may cause disinhibitory movement and behavioral disorders. The pathophysiology of disinhibitory movement and behavioral disorders was discussed in relation to the role of the frontal lobe in motor control and hemispheric asymmetry of motor functions. Instinctive grasp reaction is the prototype of disjunctive motor disinhibition syndromes, and diagnostic dyspraxia and compulsive manipulation of tools are the most illustrative forms. Diagnostic dyspraxia can be defined as uncontrolled cross-purposeful actions of the left hand triggered by voluntary activities of the left hand. In compulsive manipulation of tools, a patient, with the right hand, grasp and use tolls placed in front of them against the patient's will. The left hand often restrains the unintentional movement of the right hand in accordance with the patient's will. Utilization and imitation behaviors described by Lhermitte et al belong to disinhibitory behavioral disorders, in which volition of the patient or an individual as a whole is involved. External stimuli reflexively provoke the patient's will to act. The behaviors accordant with the will, even if inappropriate, are not compulsive, but the easily-raised volition in response to the stimuli is pathological. These disinhibitory disorders differ from disjunctive motor disinhibition syndromes because of lack of inconsistency between will and manifested behavior. Lesions in the frontal lobes has been suggested to be responsible for utilization and imitation behaviors.

Cerebral Infarction↗

PubMed2026

Pervasive hybridization and introgression in Diervilleae (Caprifoliaceae).

Diervilleae (Caprifoliaceae) is a horticulturally important lineage with striking floral diversity and a long history of interspecific crossing, suggesting reticulate evolution. We integrated nuclear SNPs and whole plastome data to reconstruct a phylogenomic backbone for the tribe and to identify hybrids, cultivated accessions, and introgression among lineages. Nuclear and plastid phylogenies consistently recover Weigela and Diervilla as reciprocally monophyletic and resolve four major lineages within Weigela, providing a reproducible framework for revising sectional limits and species boundaries. Cultivated accessions form a well supported clade sister to W. florida and show predominantly W. florida ancestry while retaining contributions from multiple wild lineages, consistent with recurrent crossing, backcrossing, and selection. Analyses of wild populations reveal recurrent hybrids and enable plausible parental combinations to be inferred. Tests across the genome further indicate strong evidence for historical introgression across Diervilleae, with the strongest signals involving W. middendorffiana, W. maximowiczii, and Diervilla. Fossil evidence, divergence time estimation, and paleodistribution modelling together suggest range expansion during the Miocene and Pliocene followed by climate driven contraction, providing a spatiotemporal context for episodic contact, introgression, and the East Asia-North America disjunction.

Hybridization, Genetic↗

PubMed1975

Convergence-evoked nystagmus. Congenital and acquired forms.

Pendular nystagmus occurring during binocualr fixation and pursuit of near objects is true convergence-evoked nystagmus. Two forms of this nystagmus are described, one congenital and the other acquired in the course of multiple sclerosis. The congenital form was conjugate and the acquired form disjunctive. Neuropathological examination provided no morphological explanation for the congenital pattern. These two unique forms of nystagmus are induced by one of the visuomotor subsystems controlling convergence.

Adult↗

PubMed1985

The clinical spectrum of internuclear ophthalmoplegia in multiple sclerosis.

The eye movements of 100 patients with multiple sclerosis were examined clinically, including a saccade test. Thirty-four cases of internuclear ophthalmoplegia were found, of which 14 were bilateral and 20 were unilateral. Only three patients had full restriction of adduction, whereas 16 had no restriction at all. A continuous dissociated nystagmus was present in one patient only, while in 15 just a few beats of the abducting eye could be observed. In ten cases both restriction of adduction and dissociated nystagmus were lacking, and the diagnosis could only be made with the saccade test, which in all 34 patients showed a clearly visible disjunction of horizontal saccades. In 15 cases, infrared oculography was performed, which in all cases confirmed the clinical findings, and which in some cases disclosed an additional subclinical internuclear ophthalmoplegia on the opposite side.

Adult↗

PubMed1983

Botulin ophthalmoplegia. Clinical and oculographic observations.

Two patients with botulin ophthalmoplegia had rapid quivering eye motions during attempts to refixate laterally placed objects; these abnormal eye movements occurred in conjunction with a disjunctive limitation of range of eye movements. Oculographic examination showed that the quivering motions were composed of multiple hypometric saccades, many of which had subnormal and stuttering velocities. By blocking acetylcholine release into myoneural junctions, botulin toxin seems to limit the duration of saccadic burst innervation reaching ocular muscle.

Botulism↗

PubMed1998

Development of a research child growth reference and its comparison with the current international growth reference.

OBJECTIVE: To better characterize childhood growth and further assess potential limitations of the current National Center for Health Statistics and World Health Organization international growth reference. DESIGN: The LMS method was used for curve fitting to summarize the changes in height and weight distributions by 3 curves representing the skewness (L), median (M), and coefficient of variation (S). A series of polynomial regression procedures was applied to smooth the L, M, and S curves. SETTING: Subset data from 18 states contributing clinic data to the Centers for Disease Control and Prevention Pediatric Nutrition Surveillance System were used for this research reference. METHODS: We chose only those clinics in which the height and weight distributions of children closely matched with those of the first and second National Health and Nutrition Examination Surveys. RESULTS: Unlike the current international growth reference, the new reference has no disjunction at 24 months of age because it is based on a single data source for children aged 0 to 59 months. The reference also better characterizes the growth for infants than the current international reference, a fact we demonstrated with data from the National Health and Nutrition Examination Surveys, Pediatric Nutrition Surveillance System 1995, and the Davis Area Research on Lactation, Infant Nutrition, and Growth studies. CONCLUSIONS: The current National Center for Health Statistics and World Health Organization international growth reference needs to be updated. The methods used in this study will be useful to evaluate other data sets and to evaluate future modifications of growth references.

Body Height↗

PubMed2026

Circulating Methylated SEPT9 for Detection of Hepatocellular Carcinoma in Cirrhosis.

IMPORTANCE: Hepatocellular carcinoma (HCC) surveillance in patients with cirrhosis remains suboptimal, with inadequate early-stage detection. α-Fetoprotein (AFP) demonstrates insufficient sensitivity. Circulating methylated septin 9 (SEPT9) has shown diagnostic promise. OBJECTIVE: To determine whether methylated SEPT9 improves detection of HCC when combined with AFP in patients with cirrhosis undergoing surveillance. DESIGN, SETTING, AND PARTICIPANTS: In this prospective, cross-sectional, diagnostic accuracy study, patients with cirrhosis undergoing routine HCC surveillance with ultrasonography and AFP were enrolled at 2 French academic centers from February 2018 through October 2024. HCC was diagnosed per international guidelines with centralized radiologic review, blinded to methylated SEPT9 results. Data were analyzed from October 2025 to January 2026. EXPOSURES: Plasma methylated SEPT9 was analyzed from 3 independent plasma aliquots and classified by number of positive replicates (single-positive, double-positive, or triple-positive). Serum AFP was evaluated at a threshold of 20 ng/mL. Biomarkers were evaluated individually and in combination using disjunction logic (tier 1; maximizing sensitivity) or conjunction logic (tier 2; maximizing specificity). MAIN OUTCOMES AND MEASURES: The primary outcome was the presence of HCC at enrollment. The primary end point was comparison of the area under the receiver operating characteristic curve (AUROC) between methylated SEPT9 and AFP. Secondary end points included diagnostic performance stratified by Barcelona Clinic Liver Cancer (BCLC) stage. RESULTS: Among 574 participants, 414 (72.1%) were male, and the median (IQR) age was 63 (57-70) years. A total of 118 had HCC, including 51 (43.2%) with BCLC stage 0-A. Methylated SEPT9 outperformed AFP (AUROC: 0.79 [95% CI, 0.74-0.84] vs 0.71 [95% CI, 0.66-0.76], respectively; P = .002; posterior probability of superiority >99.8%). Tier 1a (at least single-positive methylated SEPT9 or AFP >20 ng/mL) achieved 87.8% (95% CI, 81.6-93.5) sensitivity and a negative likelihood ratio of 0.2 (95% CI, 0.1-0.3). Among 64 HCC cases missed by AFP, tier 1a recovered 50 (78%). For BCLC 0-A disease, tier 1a sensitivity was 74.5% (95% CI, 62.2-86.5) vs 23.5% (95% CI, 12.5-35.8) for AFP, 3.2-fold increase. Tier 2 (triple-positive methylated SEPT9 and AFP >20 ng/mL) achieved 99.6% (95% CI, 98.9-100) specificity, a positive likelihood ratio of 76.0 (95% CI, 26.9-181.0), and a diagnostic odds ratio of 112.1 (95% CI, 37.8-294.7). CONCLUSIONS AND RELEVANCE: In this diagnostic study, combining methylated SEPT9 with AFP substantially improved HCC detection in patients with cirrhosis, particularly for early-stage disease amenable to curative treatment. Prospective studies are needed to determine whether improved detection translates into survival benefit.

Humans↗