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BACKGROUND: One-third of infants have ear anomalies, and less than one-third self-correct. Correction of ear deformities by molding exploits the plasticity of the auricular cartilage because of circulating maternal estrogen during infancy. In this study, the authors assess the efficacy of the EarWell Infant Correction System in the correction of ear deformities and determine the factors that affect its outcome. METHODS: The authors conducted a single-center prospective study over a 3-year period. Consecutive full-term infants who underwent ear molding with the EarWell system were recruited. Primary outcome was successful correction of ear anomaly. Secondary outcomes included complications and maintenance of ear shape. Factors identified included type of anomaly, age at application, duration of application, and breastfeeding. RESULTS: Sixty-seven patients with a total of 105 ears were recruited. The anomalies were classified into deformations (66.7 percent) and malformations (33.3 percent). The median age group at presentation was 0 to 7 days (67 percent). Average duration of application was 4.1 weeks. Successful correction was achieved in 86 percent of patients. Ear deformations achieved a significantly higher rate of successful outcome (98 percent) compared with malformations (64 percent) (p < 0.001). Skin complications were common (46 percent) and attributed to our tropical climate. Patients with complications were of a higher mean age (22.1 days) compared with patients with no complications (10.6 days) (p = 0.037). CONCLUSIONS: The EarWell system is an effective nonsurgical option for the treatment of ear anomalies. The type of anomaly was the only predictor of successful correction, whereas age at application, duration of molding, and breastfeeding were not. Complications were more common in older infants. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

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PURPOSE: We describe a homodigital neurovascular island flap for reconstructing large pulp defects of the fingertips and review the short-term and long-term appearance and function of the reconstructed fingertips. METHODS: The spiral flap is a homodigital neurovascular island flap with a unique spiral advancement and transposition design that allows pulp reconstruction using sensate glabrous skin while restricting donor morbidity to the injured digit. Thirty-two fingertips were resurfaced using this flap. All had large pulp defects averaging 1.2 cm wide x 2.0 cm long (1.0-2.0 cm x 1.5-2.5 cm). Short-term results (<18 months) for all patients at a minimum of 6 months and long-term results (>5 years) for 10 patients with a mean follow-up of 13 years were reviewed. Objective outcome measures included static 2-point discrimination, degree of nail deformity (beaking), total active motion, and hypersensitivity or cold intolerance. Subjective outcome measures included patient satisfaction with function and aesthetics, using a visual analog scale. RESULTS: All flaps achieved primary healing with no complications. There was initially mild extension deficit in the proximal interphalangeal and distal interphalangeal joints, which improved to full range of motion in the long term. Sensory recovery was excellent, with an average 2-point discrimination of 5 mm initially, improving to 4 mm in the long term. Nail beaking was minimal initially but increased significantly in the long term. These results may be explained by soft tissue remodeling. All patients on long-term follow-up were highly satisfied with both aesthetic and functional outcome. There was no hypersensitivity or cold intolerance at either the short-term or long-term follow-up assessments. CONCLUSIONS: The spiral advancement-transposition flap is suitable for resurfacing large pulp defects with excellent short-term and long-term functional and aesthetic results and high patient satisfaction. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

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The amidation of a synthetic peptide D-Tyr-Pro-Gly-Gly by sheep hypothalamic and pituitary preparations was measured. This substrate was designed as a glycine-extended C-terminal peptide analogue of gonadotropin-releasing hormone (GnRH) to test the ability of these tissues to convert the product produced by cleavage of the GnRH prohormone into the active amidated decapeptide. An alpha-amidating activity capable of converting D-125I-Tyr-Pro-Gly-Gly into D-125I-Try-Pro-Gly-NH2 was identified in crude synaptosomal and neurosecretory-granule fractions from hypothalamus and anterior-pituitary secretory-granule preparations. This activity was stimulated by the addition of Cu2+ and reduced ascorbate, and was maximal at neutral pH in sulphonic acid buffers. Highest activity was measured in synaptosomes from the median eminence and medial basal hypothalamus and in pituitary granules. Lower activity was found in synaptosomes prepared from anterior hypothalamic tissue. Negligible activity was measurable in cerebral cortex and none in pineal synaptosomes. Direct comparison of alpha-amidation with D-125I-Try-Pro-Gly-Gly and a previously reported substrate D-125I-Tyr-Val-Gly showed that, although the latter was 15-20-fold more reactive, the optimal concentration of Cu2+ for amidation was similar with both substrates in medial-basal-hypothalamic synaptosomes and pituitary granules. Activity measured with 1 microM-D-125I-Tyr-Val-Gly was inhibited by increasing concentrations of D-Tyr-Pro-Gly-Gly, with 50% inhibition at 25 microM-D-Tyr-Pro-Gly-Gly, whereas activity with 3.3 microM-D-125I-Tyr-Pro-Gly-Gly was abolished by addition of 1 microM-D-Tyr-Val-Gly, evidence that the two substrates were competing for the same enzyme activity. Synaptosomal preparations demonstrated Michaelis-Menten kinetics for D-Tyr-Pro-Gly-Gly as substrate, with values of Km and V decreasing upon removal of ascorbate. We conclude that D-Tyr-Pro-Gly-Gly-directed alpha-amidation in sheep hypothalamic synaptosomes resembles the activity with D-Tyr-Val-Gly as substrate, as well as that demonstrated by others with D-Tyr-Val-Gly as substrate in rat hypothalamic and pituitary tissue. Although reactivity towards D-Tyr-Pro-Gly-Gly cannot be assumed to assess amidation solely of GnRH, the negligible D-Tyr-Pro-Gly-Gly-directed activity in the pineal gland and cerebral cortex, areas that are known to synthesize other alpha-amidated peptides, suggests some substrate specificity in alpha-amidating enzymes from different tissues.

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The presence of a fecundity gene (F) in Booroola Merino ewes increases the ovulation rate. To test how F gene expression affects the gonadotrophin-releasing hormone (GnRH) concentration in hypothalamic or extrahypothalamic regions of the brain, GnRH was measured by radioimmunoassay in acetic acid extracts of various brain tissues from Booroola ewes which were homozygous (FF), heterozygous (F+) or non-carriers (++) of the F gene. The GnRH concentration in brain tissues from FF, F+ and ++ animals which had been ovariectomized 5 months previously was also evaluated. No significant F gene-specific differences were noted in any of the brain areas tested, in intact or ovariectomized animals. However, in ovariectomized ewes, the concentrations of GnRH increased about 2-fold in the median eminence of the hypothalamus, remained unchanged in the medial basal hypothalamus and dropped to less than 10% of the values in intact ++ animals in the preoptic area. These studies suggest that the changed pituitary sensitivity and increased gonadotrophin release in Booroolas carrying the F gene(s) is not attributable to increased hypothalamic GnRH concentrations in these animals.

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Peritoneal macrophages from mice, isolated rat liver Kupffer cells and rat testis Leydig cells ingested large numbers of Percoll particles, a gradient medium widely used for separation of cells and subcellular organelles by density-gradient centrifugation. A decrease in the percentage of macrophages adhering to plastic also occurred after exposure of the cells to Percoll, even at 4 degrees C, a temperature at which Percoll was not ingested. The effect of Percoll on macrophage adherence may involve a loose association between the density medium and the cell surface. Other cell-surface-related phenomena may also be affected by prior exposure of cells to Percoll.

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A rapid method for preparing Leydig cells from rat testes is described. An interstitial cell suspension, prepared by collagenase treatment of decapsulated testes, was centrifugal for 10 min over a cushion of 60% (v/v) Percoll to remove red blood cells, and then centrifuged for 20 min in a 0-60% linear density gradient of Percoll. Seventy-four per cent of the cells present in that fraction of the gradient comprising 35-50% Percoll were Leydig cells; the yield from each testis was about 1.5 x 10(6) cells. The Leydig cells appeared viable, excluded Trypan blue, possessed high-affinity binding sites for human chorionic gonadotrophin (hCG) and synthesized increased quantities of testosterone in response to hCG. The cells could be stored overnight in 20% (v/v) glycerol at -20 degrees C, with only minimal effect on the specific activities of a number of enzymes used as markers of subcellular components. Testosterone production in vitro by the cells after storage for 20 h was greater than that of hCG-stimulated fresh cells and was not further increased by hCG.

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Whole sheets of plasma membrane, each with their attached flagellum, were purified from Trypanosoma brucei. The method devised for their isolation included a new technique of cell breakage that used a combination of osmotic stress followed by mechanical sheer and avoided the problem of extreme vesiculation as well as the trapping of organelles in cell 'ghosts'. The purified membranes all contained the pellicular microtubular array. The antigenic surface coat was completely released from the plasma membrane during the isolation procedure. The membranes had a very high cholesterol/phospholipid ratio (1.54). A large proportion (42%) of the cellular DNA was recovered in the plasma-membrane fraction unless a step involving deoxyribonuclease treatment, which decreased the DNA content to less than 13%, was included before secrose-density gradient centrifugation. This step also aided the separation of plasma membranes from other cellular components. The ouabain-sensitive Na+ + K+-stimulated adenosine triphosphatase and adenylate cyclase co-purified with the plasma membranes. Although 5'-nucleotidase was thought to be a plasma-membrane component, it was easily detached from the membrane. The purified membranes were essentially free of L-alanine-alpha-oxoglutarate aminotransferase, L-asparte-alpha-oxoglutarate aminotransferase, malate dehydrogenase, oligomycin-sensitive adenosine triphosphatase, glucose 6-phosphatase, Mg2+-stimulated p-nitrophenyl phosphatase and catalase.

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The hemocyanin from the crayfish Jasus edwardsii(=lalandii) has been studied using ultracentrifugation, viscosity, circular dichroism and oxygen binding techniques. Sedimentation velocity experiments at pH 7.0 indicated the presence of principal species with S 20w=16.4 S, and at higher pH the presence of a species with S20,w=5.2S. Sedimentation equilibrium experiments yielded molecular weights of 490 000 and 81 000 respectively, indicating that the larger unit is a hexamer of the monomer unit. However, preliminary experiments with gel filtration and electrophoresis under denaturing conditions indicate that more than one monomer species may be present with molecular weight in the range 76-100 000. Circular dichroism (CD) spectra are presented at pH 7.0,8.6,10.0 and 11.0 for oxy-, deoxy- and apo-hemocyanins. Slight differences were observed in the magnitude of the bands in the presence or absence of Mg++. Oxygen binding studies have been made at pH 6.1,7.0,8.8 and 10.6, in the presence of 0.01 M MgCl2. The extent of cooperative binding was indicated by a maximum value of n=3.7, and a pronounced bohr effect was observed.

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