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Time analysis of corneal endothelial cell density after cataract extraction.

Serial endothelial photographs were taken preoperatively and postoperatively in 200 eyes; 111 eyes contained a Rayner iris clip lens, 54 eyes contained a Fyodorov Sputnik lens, and 35 eyes had no lens. Central endothelial cell density was changed in all instances, with counts in implanted eyes declining 25 to 30%, and in nonimplanted eyes 10 to 15%. In both instances, the decline essentially ceased at about three months. The cause of the greater decline in implanted eyes appeared to be mechanical and subsequent cell loss after the 90-day period was virtually equal for the two groups. Methods that may be used to alter the difference in cell density occurring with implantation are best analyzed by using the 90-day period data for comparison.

Animals

Physiological responses in rats fed extracts of endophyte infected tall fescue seed.

Three trials involving 184 male Sprague Dawley rats were conducted to identify the biologically active fraction of endophyte-infected tall fescue seed. In trial 1, seed infected (greater than 95%) with the endophytic fungus Acremonium coenophialum and shown to be toxic to cattle, was serially extracted with hexane, ethylacetate, and methanol, respectively. A second sample of this seed was extracted with chloroform only. Controls included a solvent treatment (spraying the various solvents on endophyte-free seed and carrying the mixture to dryness), the seed post-extraction, endophyte-infected seed and endo-phyte-free seed. Laboratory chow was mixed with all diets to provide 50% of the mix. Trial 2 examined the same treatments as trial 1 except that the chloroform treatment was omitted. Dosages 3 times (equivalent to 22.5 g seed) those used in trial 1 were applied to endophyte-free seed (7.5 g) in an attempt to accentuate any differences. Trial 3 examined the methanol fraction extracted serially, a methanol fraction extracted batchwise, and a water fraction extracted batchwise. Controls included seed residues post-extraction, solvent residue from methanol sprayed on endophyte-free seed, and endophyte-infected seed. Lowered feed intake and weight gains, and depressed serum prolactin concentrations were used as indicators of toxicity. Feed intake was lower in all three trials for rats fed the methanol fraction. In all three trials mean serum prolactin concentrations in rats fed the methanol extracts were not different from those fed endophyte-infected fescue seed. Rats fed the water extract in trial 3 had lower feed intakes than rats fed endophyte-free seed. However, rats fed the seed, post-water extraction, had serum prolactin concentrations similar to that of the negative control. Results suggest that the toxic factor(s) may be concentrated in the methanol extract.

Acremonium

Premolar enucleation.

A study was made on 27 cases where enucleation of four first premolars was performed simultaneously without introduction of mechanical devices to influence space closure. The results suggested that: 1. Enucleation of premolars can be used to minimize the severity of crowding in arch-length deficiency cases. 2. There is no damage to the remaining teeth and alveolar process when enucleation is accomplished with good surgical technique. 3. The average amount of lingual tipping of the mandibular incisors in approximately four years subsequent to the enucleation procedure was 4.1 degrees. 4. This amount of lingual tipping compares quite favorably with the amount of lower incisor uprighting experienced during growth and could not be considered excessive. 5. The mandible does tend to rotate in a counterclockwise manner following enucleation of four first premolars without appliance therapy. This rotation was considered significant in comparison with the amount of rotation that could be expected from an untreated sample. 6. If orthodontic treatment is planned, the enucleation of the manddibular second premolars in borderline extraction cases to avoid excessive lingual tipping of the mandibular incisors would seem to be questionable. 7. Various combinations of enucleation and tooth extraction may be helpful in treatment planning. 8. With judicious timing the enucleation of four first premolars can minimize the severity of the malocclusion simplifying appliance therapy if proper diagnosis and good surgical technique are employed. 9. Although conventional serial extraction may accomplish similar ends, it would appear that enucleation would offer some advantages in terms of autonomous adjustment of the mandibular incisors and root positioning of mandibular cuspids. 10. Enucleation cases usually require fewer traumatic surgical procedures and less supervision by the orthodontist. 11. The parents should be informed that serial extraction procedures including enucleation may simplify but will not eliminate the need for appliance therapy.

Bicuspid

The neuroendocrine thymus: coexistence of oxytocin and neurophysin in the human thymus.

Immunoreactive oxytocin and neurophysin were identified and measured by radioimmunoassay in human thymus extracts. Serial dilutions of extracts paralleled the appropriate standard curves. Thymus-extracted oxytocin and neurophysin eluted in the same positions as reference preparations on Sephadex G-75. Authenticity of oxytocin was confirmed by biological assay and high-performance liquid chromatography analysis. In most instances, thymus contents of oxytocin and neurophysin were far greater than those expected from known circulating concentrations and declined with increasing age. The molar ratio of oxytocin to neurophysin in thymus was similar to that found in the hypothalamo-neurohypophyseal system, which strongly suggested with the other data a local synthesis of oxytocin. These findings indicate the presence of neurohypophyseal peptides in the human thymus and further support the concept of a neuroendocrine function integrated in an immune structure.

Adult

[Case report of progenie with a congenitally missing mandibular right incisor].

The female in this case was 9 years and 9 months old at the initial visit with a dental stage of III B. The chief complaint was anterior cross bite. Diagnosis revealed a class III angle at the right side and class I at the left. The ANB angle was -3.0 degrees with mandible shifting to the left side. Tooth size was large, and a lack of space, observed, and 2 was congenitally missing. A chin cap was used for treatment to retract and inhibit mandibular growth. The anterior cross bite was corrected within two months when class I angle molar relationship was achieved and the extraction of midline was also corrected. Since the lack of space in the upper arch was about 10 mm, extraction of 5 was decided, although the assigned ANB angle improved to be -0.5 degree within one year of treatment. 3 was to replace the position of the congenitally missing 2. At the age of 11 years and 1 month, 4 was extracted to guide the eruption of 3. 4 and E were extracted guide the eruption of 3 and 5. Then 5 was extracted. As a result of these serial extractions, space closing and leveling were automatically achieved without use of the multibracket system. Good stable occlusion has been maintained up to the present age of 15 years and 8 months.

Anodontia

Immuno-reactive and bioactive corticotropin-releasing factor in rat thymus.

Immunoreactive corticotropin-releasing factor (CRF) was identified and measured by radioimmunossay in rat thymic extract. Serial dilutions of thymic extract paralleled hypothalamic extract and synthetic CRF standard curves. CRF extracted from rat thymus eluted in the position of synthetic rat CRF on Sephadex G-25 column. Thymus-derived CRF was biologically active as demonstrated by stimulating adrenocorticotropic hormone secretion in dispersed rat anterior pituitary cells. These findings indicate the presence of authentic CRF in rat thymus, further supporting the concept of an integrated regulation of the neuroendocrine-immune responses to environmental stimuli.

Animals

A long-term study of the relationship of third molars to changes in the mandibular dental arch.

The purpose of this study is to determine the relationship of third molars to changes in the mandibular dental arch. The sample for this study consisted of four groups and subgroups. The groups consisted of premolar extraction treated, nonextraction treated with initial generalized spacing, nonextraction treated, and serial extraction untreated subjects. The subgroups were divided into persons who had mandibular third molars that were either impacted, erupted into function, congenitally absent, or extracted at least 10 years before postretention records. The mean postretention time interval was 13 years, with a range of 10 to 28 years. The mean postretention age was 28 years 6 months, with a range of 18 years 6 months to 39 years 4 months. Two-way analysis of variance with repeated measures was used to compare the changes over time (before treatment, at end of active treatment, and after retention) of groups and third molar subgroups. With time, mandibular incisor irregularity increased while arch length and intercanine width decreased. The eruption patterns of mandibular incisors and first molars were similarly dispersed in all groups studied. The findings between the subgroups in which mandibular third molars were impacted, erupted into function, congenitally absent, or extracted 10 years before postretention records revealed no significant differences between any of the subgroups for the parameters studied. No significant differences in mandibular growth were found between the third molar subgroups; this suggests that persons with third molars erupted into satisfactory function do not have a significantly different mandibular growth pattern than those whose third molars are impacted or congenitally missing. In the majority of cases some degree of mandibular incisor crowding took place after retention, but this change was not significantly different between third molar subgroups. This finding suggests that the recommendation for mandibular third molar removal with the objective of alleviating or preventing mandibular incisor irregularity may not be justified.

Adult

Human placental immunoreactive corticotropin, lipotropin, and beta-endorphin: evidence for a common precursor.

The concentrations and molecular sizes of immunoreactive corticotropin (ACTH), lipotropin (LPH, beta LPH plus gamma LPH), gamma LPH, and beta-endorphin (beta END) were determined in human placental extracts. Serial dilutions of a water extract of placenta generated competitive binding curves parallel with that of the standard in each assay. The concentrations of ACTH, LPH, gamma LPH, and beta END were 3.3, 0.8, 0.7, and 1.1 ng/g wet weight of tissue, respectively. A partially purified extract applied to a Sephadex G-50 column contained high Mr components with ACTH, LPH, gamma LPH, and beta END immunoreactivities. The extract was applied to an immune affinity chromatography column consisting of affinity-purified (1-24)ACTH antiserum covalently bound to agarose. The material that adsorbed to the column and eluted with buffer containing sodium dodecyl sulfate had ACTH, LPH, and beta END immunoreactivities, indicating that there was a component or components containing antigenic determinants for all of these peptides. Sodium dodecyl sulfate/polyacrylamide gel electrophoresis of the affinity-purified placental extract revealed at least two high Mr components (Mr approximately 48,000 and 36,000) with all three immunoreactivities. These data suggest, but do not prove, that the placenta synthesizes ACTH, the LPHs, and beta END from a common precursor molecule.

Adrenocorticotropic Hormone

[Early orthodontic treatment].

Several preventive procedures are recommended for the interception of early malocclusion. Therefore some important characteristics of normal dental development are mentioned. This preventive approach is focused around selected topics as forced bite, midline diastema and retarded eruption. This influence of functional disturbances on dentofacial morphology is discussed. An overview of possible therapy by the general dentist is presented for problems, aroused by thumb- and fingersucking, agenesis of upper lateral and mandibular second premolars as well as early loss of deciduous molars. Finally, the possible indications for serial extractions are examined.

Child

[From the mixed dentition to the permanent dentition: how to manage space while guiding eruption?].

In the mixed dentition, when there is a discrepancy between the bony structures and the teeth, in certain cases, serial extractions are performed in order to guide the eruption of permanent teeth and obtain a correct occlusal function. The treatment consists in the extraction of primary teeth and then of first bicuspids. The choice of the first tooth to be extracted is based upon the position of the crowns of the permanent teeth and their degree of root maturation. Then the first bicuspid is extracted as soon as or prior to its eruption. This interceptive treatment has limited indications which need to be respected in order to preserve the child's future dental health. This treatment is indicated for Class I malocclusions with severe crowding or moderate crowding associated with bi-maxillary protrusion.

Child

Reattachment of surface array proteins to Campylobacter fetus cells.

Campylobacter fetus strains may be of serotype A or B, a property associated with lipopolysaccharide (LPS) structure. Wild-type C. fetus strains contain surface array proteins (S-layer proteins) that may be extracted in water and that are critical for virulence. To explore the relationship of S-layer proteins to other surface components, we reattached S-layer proteins onto S- template cells generated by spontaneous mutation or by serial extractions of S+ cells with water. Reattachment occurred in the presence of divalent (Ba2+, Ca2+, Co2+, and Mg2+) but not monovalent (H+, NH4+, Na+, K+) or trivalent (Fe3+) cations. The 98-, 125-, 127-, and 149-kDa S-layer proteins isolated from strains containing type A LPS (type A S-layer protein) all reattached to S- template cells containing type A LPS (type A cells) but not to type B cells. The 98-kDa type B S-layer protein reattached to SAP- type B cells but not to type A cells. Recombinant 98-kDa type A S-layer protein and its truncated amino-terminal 65- and 50-kDa segments expressed in Escherichia coli retained the full and specific determinants for attachment. S-layer protein and purified homologous but not heterologous LPS in the presence of calcium produced insoluble complexes. By quantitative enzyme-linked immunosorbent assay, the S-layer protein copy number per C. fetus cell was determined to be approximately 10(5). In conclusion, C. fetus cells are encapsulated by a large number of S-layer protein molecules which may be specifically attached through the N-terminal half of the molecule to LPS in the presence of divalent cations.

Animals

Charge heterogeneity of rat pituitary prolactin in relation to the estrous cycle, gonadectomy, and estrogen treatment.

Pituitary samples were obtained from female rats at various stages of the estrous cycle, and from intact male and gonadectomized rats with and without estradiol treatment. The pituitary extracts with 60% EtOH pH 9.5, were fractionated by preparative isoelectric focusing (IEF), and immunoreactive prolactin (IR-PRL) was measured by RIA. Three types of IR-PRL molecular species were found in these IEF profiles. The first type (species A) was consistently found in an area of pH 4.5-5.4, and consisted of two main subspecies with pls 5.0 (Al) and 5.25 (A2). Species A occupied most part of pituitary IR-PRL in males, gonadectomized animals, and in females in a basal state such as diestrus (D) II 17:00. Species A was also found exclusively in the serum at proestrus (PE) 19:00. The amounts of species A decreased notably when the secretion became active from PE 15:00 to 22:00, then increased at estrus (E) 6:00 and 10:00 when the second type (species B), which was found in the area of pH 5.4-6.8 only in trace amounts at basal states, increased markedly. Species B decreased again at E 17:00, while species A fully recovered. Species B also increased when PRL biosynthesis was stimulated by estradiol in intact male and gonadectomized rats. These findings indicate that species A must be the storage and secretory type of IR-PR, and that species B must be IR-PRL in the biosynthetic process which is to be finally converted into species A. A third type (species C) was found in a region of pH 3.5-4.5 in the IEF profiles of gonadectomized animals. This species is possibly IR-PRL molecules under degradation. When the pituitary was extracted serially with 0.25 M ammonium sulfate pH 5.5 (fraction AMS) first, then with 60% EtOH pH 9.5 (fraction ET), fraction AMS contained mostly species B and C, while fraction ET contained species A almost exclusively. The results obtained with this differential extraction roughly coincided with IEF data, though some disagreements were observed.

Animals

Nonuniform behavior of multiple isoactins in the same cell is a cell-dependent phenomenon.

The functional significance of multiple isoactins in the same cell is still not understood. To address this question, we examined the response of smooth muscle and cardiac muscle alpha-isoactins to a serial extraction procedure applied to both muscle and nonmuscle cell types. We compared these extraction results with results obtained with the beta- and gamma-nonmuscle actin isoforms from the same cells. In differentiated BC3H1 nonfusing muscle cells (smooth muscle alpha-isoactin), in human rhabdomyosarcoma cells (cardiac alpha-isoactin), and in chick skeletal muscle cells (cardiac alpha-isoactin), different fractions were found selectively enriched in either the nonmuscle or the muscle-specific actin isoforms compared with their relative abundance in whole cell extracts. Conversely, when these same isoactins were examined either in undifferentiated BC3H1 cells or in mouse nonmuscle cells stably transfected with a cardiac alpha-isoactin gene, no enrichment of these isoforms above their relative abundance in whole cell extracts was observed. These results indicate that within the muscle or muscle-like cells examined, the different actin isoforms were either selectively utilized or localized. These results further show that isoactin-specific responses observed were apparently related to the cell type in which they were found and not to differences in inherent physical properties such as solubility of the different isoactins examined.

Actins

Ultrastructure of the olfactory neuron of the bullfrog: the dendrite and its microtubules.

The ciliated dendritic bulb of the olfactory neuron of the bullfrog was studied with the electron microscope, with emphasis on microtubular elements. Methods used included various fixation procedures with and without detergent extraction, serial sectioning, microtubule polarity assays, and an assay to demonstrate F-actin. Structural continuity exists, via microtubules, between the ciliary membrane and the perikaryon of the neuron. One type of structural link connects the distal end of the basal body to the plasma membrane and, in slightly oblique cross sections of the basal body, the link shows a highly characteristic tripartite profile resembling a claw hammer. The six to ten basal bodies of a dendritic bulb have a lateral foot that serves as an organizing center for microtubules, and these microtubules (totaling about 150) extend toward the perikaryon in the basal half of the epithelium. Polarity assays indicate that the attached or minus ends of dendritic microtubules are in the dendritic bulb, with their plus or fast-growing ends near or within the perikaryon of the neuron. It is shown that dendritic microtubules are depolymerized by direct osmium tetroxide fixation, in contrast to olfactory axonal microtubules, which persist after such fixation. F-actin appears to be abundantly present in the dendritic bulb of the neuron, and it is possible that this actin could play a role in shape changes of the dendrite. The various findings provide new information about the olfactory dendrite, its microtubule organizing centers, and the nature and relationships of its microtubules.

Actins