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The morphogenesis of the color pattern of animals is modeled within the framework of a clonal model. The model takes into account the, sometimes conflicting, cell-cell and cell-background interactions. The color patterns of some reptiles and mammals are found to be consistent with the predictions of the model.
Following earlier work on the relationship between the micromucosal pattern of the stomach and chronic gastritis, a comparison was carried out between the appearances in the pyloric canal and the histological findings in that area. The presence of chronic gastritis could not be excluded, irrespective of the type of relief pattern. Normal gastric mucosa was only found in areas showing medium sized areae gastricae. Fundamental problems concerning the radiological technique are discussed as well as the evidence for the diagnosis of chronic gastritis.
A "normalized map" of human plasma proteins, which illustrated the standard distribution pattern of the proteins, was prepared by comparing eight two-dimensional electrophoretic gels of normal human plasma. Phenotypes of several plasma proteins were detected. The pI and molecular weight of each spot in the normalized map were calculated and 84 spots out of 128 were identified or tentatively identified as known plasma proteins by several methods including micro amino acid analysis of the proteins extracted from the stained gel pieces. Human cerebrospinal fluid and urine protein patterns were compared with the normalized map and the positions of proteins characteristic of each body fluid sample were determined.
Between March 1983 and January 1988 delayed pattern visual evoked potentials (PVEP) were observed in 67 patients with distal visual pathway dysfunction. Many of these patients had been referred for neurophysiological examination because of possible optic nerve dysfunction. These patients also had pattern electroretinography (PERG) performed which in all cases showed an abnormality of the main positive P50 component. None of these patients had an abnormality confined to the negative N95 component, the type of abnormality usually found if the PERG is abnormal in optic nerve disease. It is suggested that PERG recording should now be a routine adjunct to the PVEP in the assessment of anterior visual pathway dysfunction.
Bone morphogenetic protein-2A (BMP-2A) is a member of the transforming growth factor beta (TGF beta) gene family that has been implicated in cartilage and bone formation. Here we use in situ hybridization to show that BMP-2A RNA is expressed in a variety of embryonic epithelial and mesenchymal tissues outside of the developing skeletal system, including cell populations known to play important roles in morphogenesis. Thus, high levels of transcripts are found in developing limb buds (ventral ectoderm and apical ectodermal ridge), heart (myocardium of the atrioventricular canal), whisker follicles (ectodermal placodes, hair matrix and precortex cells), tooth buds (epithelial buds, dental papilla and odontoblasts), and craniofacial mesenchyme, as well as a number of other sites. The expression patterns of BMP-2A are different from those of TGF beta-1, -2 and -3, and this is illustrated in detail in the developing whisker follicles. These results suggest that BMP-2A plays multiple roles in morphogenesis and pattern formation in the vertebrate embryo.
A cDNA clone coding for a sea urchin embryonic protein was isolated from a prehatching blastula lambda gt11 library. The predicted translation product is a secreted 64 x 10(3) Mr enzyme designated as BP10. The protein contains several domains: a signal peptide, a putative propeptide, a catalytic domain with an active center typical of a Zn(2+)-metalloprotease, an EGF-like domain and two internal repeats similar to repeated domains found in the C1s and C1r serine proteases of the complement cascade. The BP10 protease is constructed with the same domains as the human bone morphogenetic protein BMP-1, a protease described as a factor involved in bone formation, and as the recently characterized product of the tolloid gene which is required for correct dorsal-ventral patterning of the Drosophila embryo. The transcription of the BP10 gene is transiently activated around the 16- to 32-cell stage and the accumulation of BP10 transcripts is limited to a short period at the blastula stage. By in situ hybridization with digoxygenin-labelled RNA probes, the BP10 transcripts were only detected in a limited area of the blastula, showing that the transcription of the BP10 gene is also spatially controlled. Antibodies directed against a fusion protein were used to detect the BP10 protein in embryonic extracts. The protein is first detected in early blastula stages, its level peaks in late cleavage, declines abruptly before ingression of primary mesenchyme cells and remains constant in late development. The distribution of the BP10 protein during its synthesis and secretion was analysed by immunostaining blastula-stage embryos. The intracellular localization of the BP10 staining varies with time. The protein is first detected in a perinuclear region, then in an apical and submembranous position just before its secretion into the perivitelline space. The protein is synthesized in a sharply delimited continuous territory spanning about 70% of the blastula. Comparison of the size and orientation of the labelled territory in the late blastula with the fate map of the blastula stage embryo shows that the domain in which the BP10 gene is expressed corresponds to the presumptive ectoderm. Developing embryos treated with purified antibodies against the BP10 protein and with synthetic peptides derived from the EGF-like domain displayed perturbations in morphogenesis and were radialized to various degrees. These results are consistent with a role for BP10 in the differentiation of ectodermal lineages and subsequent patterning of the embryo. On the basis of these results, we speculate that the role of BP10 in the sea urchin embryo might be similar to that of tolloid in Drosophila. We discuss the idea that the processes of spatial regulation of gene expression along the animal-vegetal in sea urchin and dorsal-ventral axes in Drosophila might have some similarities and might use common elements.
Compared with control subjects, non-insulin-dependent diabetes mellitus (NIDDM) subjects had both quantitative and qualitative abnormalities in blood insulin and glucose concentrations. The purpose of this study was to determine whether and to what extent normally observed multiphasic patterns of insulin and glucose responses to mixed meals are deranged in NIDDM. A total of 24 volunteers were studied while eating three meals of identical composition at 0745, 1145, and 1645. Twelve had NIDDM, and the remainder were healthy nondiabetic age- and weight-matched control subjects. Blood was withdrawn every 10 min from 0630 to 1930 for measurement of C-peptide, insulin, and glucose concentrations. Peaks were analyzed by computer-based algorithms. Diabetic volunteers displayed several differences from control subjects. First, although the number of insulin peaks was similar, there was a consistent delay of 20-30 min in the appearance of the first postprandial peak. Second, insulin concentrations after lunch were higher than after breakfast, whereas the reverse pattern occurred in control subjects. Third, integrated glycemia was greater after breakfast than after lunch. Fourth, glucose concentrations decreased during the first 30 min after lunch, suggesting accelerated glucose disposal and/or enhanced suppression of endogenous glucose production at this time of day. These data demonstrate that insulin secretion and action and glucose homeostasis in NIDDM are more complex than commonly appreciated. This dynamic state is undetected unless there is frequent blood sampling for measurement of insulin and glucose. The quantitative and qualitative abnormalities that we observed in these parameters are independent of obesity and suggest the need to expand the pathophysiological definition of NIDDM.
Self-disclosure patterns of adolescents were examined. Subjects (105 male and 159 female college students) were requested to complete the questionnaire on self-disclosure of 11 different aspects of self to four target-persons (father, mother, the best friend of same sex, the best friend of opposite sex). The following results were found. Both male and female showed the highest self-disclosure to the best friend of same sex, while the lowest to father. But sex differences were found in regard to both overall extent and pattern of self-disclosure. Female disclosed significantly more than male, especially to mother. Although male put the focus of self-disclosure on only the best friend of same sex, female put it on both the best friend of same sex and mother. Moreover, the subjects tend to vary the extent of self-disclosure with respect to the category to which each item about the self belonged. There was the interaction among sex, target-persons, and aspects of self.
The pattern visual evoked potential (PVEP) was analyzed in 22 patients (42 affected eyes) with retinitis pigmentosa, and in 9 cases the pattern electroretinogram (PERG) was simultaneously examined to find that (1) PVEP could be recorded in 31 (73.8%) and was normal in 17 (40.5%) of the affected eyes; (2) PVEP was related to visual acuity, being abnormal in all the eyes with visual acuity below 0.2, but normal in most eyes with visual acuity over 0.2; (3) the changes in PERG and PVEP were mostly consistent; and (4) PVEP and PERG might well be utilized for the morbid evaluation of central retina in patients with retinitis pigmentosa.
Routine measurement of spatial resolution of a gamma camera is normally performed through the use of a four-quadrant bar phantom or one of several commercially available resolution phantoms. These phantoms all provide a qualitative index of system resolution with the inherent assumption that any change in intrinsic resolution would be apparent in the bar/hole pattern image. However on nine gamma cameras, comparison of intrinsic resolution determined from the line spread function by NEMA standards and from visual estimation of a four-quadrant bar phantom image showed poor correlation. The purpose of this study was to design and evaluate a new test pattern which would provide a more accurate estimate of resolution. We developed a line resolution phantom (LRP) which consisted of a 16-cm-diameter lead disk with a series of horizontal and vertical slits. This phantom permits a quantitative estimate of intrinsic resolution (to within 0.5 mm) from a visual examination of the LRP image. Evaluation on nine gamma cameras showed good agreement between results obtained with the LRP and measurement of resolution from the line spread function. The LRP is a simple and inexpensive test phantom which should find applications in quality control and acceptance testing.
Abnormal ectopic rhythms, such as alpha-theta activities and spindles, occur in comatose patients. A case is presented in which the EEG of a comatose patient showed coexisting alpha-theta pattern activities and spindles. It is concluded that the coexistence of these rhythmic patterns in the EEG of a comatose patient implies continued physiologic functioning of a thalamocortical system deafferented by brainstem dysfunction and a lesser degree of cortical dysfunction.
On 37 patients with nasal allergy and 37 non-smoking healthy volunteers, maximal expiratory flow-volume curve and volume-time curve were obtained. To find the characteristic flow changes, the flow curves were classified into five patterns from type A to type E. The results showed that the incidence of type A was significantly lower in patients with nasal allergy than in the control group, while the rate of type E was significantly higher at 46% and the rate of type B was particularly high (32.4%) in the patient group. It was demonstrated that 77% of the subjects provided B or C flow-volume curves, while those with pale nasal mucous membranes developed D and E formats. In patients with nasal allergy, these patterns are useful in diagnosing remarkable differences in the lower airways.
Pattern electroretinograms (PERGs) were recorded from two normal human subjects in response to various spatial frequencies and stimulus areas. The maximum stimulus area was 75 degrees x 86 degrees which was achieved by using a standard TV monitor and a reduced viewing distance. The amplitude of the PERG increased with area in an approximately logarithmic fashion over the range investigated. The explanation relates to non-linearities of the stimulus, the retinal image and neural processing. The wide-angle PERG may be useful in the assessment of retinal diseases affecting the mid-peripheral inner retina, such as diabetic retinopathy.
A method is described in which gas chromatographic (GC) data obtained from cuticular hydrocarbons are treated by methods of pattern recognition. Based on a recently described sample preparation procedure, GC data are normalized to eliminate slight variations in chromatographic conditions and converted into the proper format for discriminant analysis by computer. The results of several methods of data treatment and display are discussed, based upon the chemometric system package, ARTHUR. The approach has the advantage of largely removing operator bias.
Gas chromatography (GC) data obtained from the cuticular hydrocarbons of the black imported fire ants are treated by methods of pattern recognition. Based on a recently described sample preparation procedure, GC data are normalized to eliminate slight variations in chromatographic conditions, and converted to the proper format for discriminant analysis by computer. The results of several methods of data treatment and display are discussed, based on the chemometrics system package, ARTHUR.
We have applied the experimental methods described by Ike et al. (Spatial Vision, 1987, 2, 13-29) in the study of pattern discrimination by subjects who, during childhood, experienced severe difficulties with reading and spelling. Of the six subjects studied, one still suffers from such difficulties and we show that she performs atypically in certain of the discrimination tasks. In particular, her discrimination responses for elements such as delta are markedly different from those of all other subjects. We interpret these abnormal responses on the basis of the discrimination mechanisms for line orientation and rotation of the elements which were discussed by Ike et al. (1987).
We have previously shown that check-size-specific changes of the Pattern-Electroretinogram (PERG) can be used to detect early glaucoma. This time we conducted a study to determine whether different check sizes, contrasts and eccentricities can improve the diagnostic yield. We examined 15 normal eyes (15 subjects), 32 eyes (24 patients) in stage I or II glaucoma and 36 eyes (25 patients) with ocular hypertension (OHT). Visual acuity was always better than 0.8. The stimuli were checkerboards, phase-reversing at 16 rev/s. The check sizes were 0.8 degrees or 15 degrees with contrast at 60% or 98%. The stimulation area was either "full-field" (27 degrees x 30 degrees), "central" (less than or equal to 7 degrees) or "paracentral" (greater than 7 degrees). In the glaucoma group, all PERG amplitudes were significantly reduced compared to normals: maximally for stimuli of 0.8 degrees, 98% contrast, full-field to 51% +/- 18%, and least for stimuli of 15 degrees, 98% contrast, central (to 70% +/- 20%). Under paracentral stimulation, the amplitude was reduced to 55% and in the central condition to 64%. The single-most-sensitive stimulus to separate normal and glaucoma patients was 0.8 degrees, 60% contrast and full-field, as the variance was low for this condition. Only 4 patients (8.5%) were incorrectly classified using these parameters; when 8 different stimuli were entered into the discriminant analysis, the rate was marginally reduced to 3 patients (6.4%). Seventy-five percent of the OHT eyes were classified as pathological. These results confirm previous findings that in early glaucoma, PERG amplitudes are more reduced using check sizes of 0.8 degrees compared to 15 degrees.(ABSTRACT TRUNCATED AT 250 WORDS)
Regional musculoskeletal diseases are exceedingly common in all segments of society, and dramatically so in industry. For generations, medicine has assumed that many such entities are use-associated. A critical review of several examples of back and upper extremity disease demonstrates that the literature supporting these assumptions is almost entirely anecdotal. It is argued that if defined patterns of usage were associated with defined clinical syndromes, such knowledge would have considerable therapeutic and prophylactic potential. Industrial rheumatology is proposed as an investigative discipline for the study of such relationships. The prerequisites in terms of assumptions and methods as well as potential fallacies and pitfalls are discussed.