The relation between electric auditory brain stem and cognitive responses and speech perception in cochlear implant users

Electrically evoked brainstem responses (EABR) and event-related cortical potentials were recorded in seven postlingually deaf adults who were experienced users of a Nucleus multichannel cochlear implant. The patients were divided into two subgroups: good performers and moderate performers. Poor EABR were found in two of the moderate performers. The latencies and amplitudes of the cortical N1 P2 complex in the good performers were within the same range as those of subjects with normal hearing, but were deviant in the group of moderate performers. This may indicate disturbed cochleotopical organization of the auditory cortex in the latter group. P300 measurements in the good performers showed normal latencies, whereas in the moderate performers they were prolonged. The results suggest that the outcomes of electrophysiological measurements to assess the integrity of a patient's auditory neural system on a brainstem and a cortical level, are related to the patient's performance with the cochlear implant.     

Computational determination of side chain specificity for pockets in class I MHC molecules

We show that a rapidly executable computational procedure provides the basis for a predictive understanding of antigenic peptide side chain specificity, for binding to class I major histocompatibility complex (MHC) molecules. The procedure consists of a combined search to identify the joint conformations of peptide side chains and side chains comprising the MHC pocket, followed by conformational selection, using a target function, based on solvation energies and modified electrostatic energies. The method was applied to the B pocket region of five MHC molecules, which were chosen to encompass the full range of specificities displayed by anchors at peptide position 2. These were a medium hydrophobic residue (Leu or Met) for HLA-A*0201, a basic residue (Arg or Lys) for HLA-B*2705; a small hydrophobic residue (Val) for HLA-A*6801, an acidic residue (Glu) for HLA-B*4001 and a bulky residue (Tyr) for H-2K(d). The observed anchors are correctly predicted in each case. The agreement for HLA-B40 and H-2K(d) is especially promising, since their structures have not yet been determined experimentally. Because the experimental determination of motifs by elution is difficult and these calculations take only hours on a high speed workstation, the results open the possibility of routine determination of motifs computationally.     

Stability of orthopedic and surgically assisted rapid palatal expansion over time

At the present time no reports are available on the stability between orthopedic and surgically assisted rapid palatal expansion. This study was designed to examine and compare the dental and skeletal changes over time for both orthopedic maxillary expansion and surgically assisted palatal expansion. The study was divided into two groups. Group one was orthopedically expanded and consisted of 14 males and 10 females. The ages ranged from 6 years to 12 years with a mean of 8.5 years. Group two received surgically assisted rapid palatal expansion and consisted of 12 males and 16 females with ages ranging from 13 years to 35 years and a mean age of 19.25 years. All 52 subjects were white, from the same geographic area, and were treated by the same two operators. Dental models and posterior anterior cephalograms were obtained immediately before and after expansion, at removal of the expansion device, and 1 year after removal of the appliance. A repeated measures analysis of variance test was applied to assess changes over time between groups. The surgical and nonsurgical techniques displayed similar trends over time although the surgical group contained a greater quantity of expansion. Both the orthopedic and the surgical groups showed stable results.     

Sepsis and serum cytokine concentrations

Hematological and plasma chemistry parameters were measured in 129 juvenile white storks (Ciconia ciconia), either wild or captive bred, April to June 1994. Wild storks were members of a colony in the Lozoya River Valley, Madrid, Spain. Red blood cells count, packed cell volume and hemoglobin increased significantly with age. White blood cells count, lymphocytes count and platelets decreased with age. Total solids, total proteins, fibrinogen, albumin, alpha, beta, gamma-globulins and urea increased with age. Differences between captive and wild birds were not notable.     

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PURPOSE: Color vision testing in young children typically is precluded by the motor and cognitive skills required by standard tests; yet this information can be useful for diagnosis and counseling in many conditions. The purpose of this study is to evaluate a visual evoked potential (VEP) method for assessing red-green color vision anomalies in pediatric patients. METHOD: The relative chromatic luminance (C = R/R + G) of a rapidly reversing red-green checkerboard was varied across a wide range within a short viewing period (10 sec). Swept-parameter VEP methods were used to measure the cortical response to the range of C presented. RESULTS: Individuals with normal color vision exhibit a VEP response that exceeds noise levels across all values of C, often with an amplitude minima near the photopic equiluminant point (C = 0.5). Results from children with established protan and deutan color vision anomalies show loss of VEP amplitude and phase at values of C consistent with the respective color defect. A patient with achromatopsia showed a generalized depression of VEP response across all values of C tested. CONCLUSION: Color sweep VEP techniques appear promising for the clinical assessment of color status in pediatric patients.     

Focal epithelial hyperplasia: human-papillomavirus-induced disease with a genetic predisposition in a Venezuelan family

A study on the presence of human papillomavirus (HPV) DNA sequences and focal epithelial hyperplasia (FEH) in a family of Venezuelan ancestry has revealed that FEH is an HPV-induced disease presenting familial aggregation. The genealogical evidence indicates a genetic predisposition to the disease.     

Coparental and family group-level dynamics during infancy: early family precursors of child and family functioning during preschool

This study examines longitudinal correlates of coparental and family group-level dynamics during infancy. Thirty-seven couples observed at play with their 8-11-month-old infants (15 boys, 22 girls) rated their child's internalizing and externalizing symptoms, and their own coparenting behavior 3 years later. Teachers also rated child behavior at the 3-year follow-up. Several significant relationships emerged between observed family process (high hostility-competitiveness, low family harmony, and high parenting discrepancies in the triad) at Time 1, and subsequent reports of child and coparenting behavior at Time 2. Larger parenting discrepancies at Time 1 predicted greater child anxiety as rated by teachers; greater hostility-competitiveness and lower harmony forecast higher child aggression. Time 1 family process continued to predict Time 2 aggression even after controlling for individual and marital functioning. Several links were also found between distressed family process and later parental reports of negative coparenting behavior. These parental reports of coparenting also explained unique variance in concurrent child behavior ratings. The significance of coparenting as a distinct family construct is discussed.     

Validated capillary electrophoresis method for the determination of atropine and scopolamine derivatives in pharmaceutical formulations

The simultaneous determination of atropine and scopolamine derivatives, which have similar structures, was investigated by using capillary zone electrophoresis. The effects of buffer pH, buffer concentration and hydroxypropyl-beta-cyclodextrin concentration on migration time and resolution of the investigated compounds were systematically studied. The selected electrophoretic buffer consisted of a 80 mM sodium citrate pH 2.5, containing 2.5 mM hydroxypropyl-beta-cyclodextrin as the complexing agent. Quantitative analysis was validated by testing the reproducibility of the method, giving a relative standard deviation less than 1 and 2% for the intermediate precision of migration times and peak area ratios, respectively. The linearity of the method was assessed between 50 and 150% of the theoretical content (coefficient of correlation greater than 0.99). The proposed method was found to be suitable and accurate for the determination of these basic drugs in pharmaceutical preparations.     

Local recurrence of a phyllodes tumour of the breast presenting with widespread differentiation to a telangiectatic osteosarcoma

Characteristic biliary tree abnormalities in metachromatic leukodystrophy (MLD) include gallbladder polyposis and haemobilia. We report two brothers with MLD, who presented with uncommon biliary complications. One presented with gastric outlet obstruction secondary to gallbladder enlargement, which was treated by percutaneous aspiration. He later developed gallbladder carcinoma with liver metastases. His brother demonstrated US findings consistent with gallstones.