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PubMed2006

Dermoscopic patterns of the filiform papillae of the tongue in patients with Sjögren's syndrome.

The purpose of this study was to determine whether there are any differences in the appearance of tongue-surface structure in different kinds of collagen diseases, because red tongue is well known to be a very important feature of suspected Sjögren's syndrome (Sjs). To clarify some features of the filiform papillae on the dorsal surfaces of the tongues of patients with speculated Sjs, we observed a total of 565 individuals with primary Sjs (n = 24, M/F = 0/24), secondary Sjs (n = 16, M/F = 1/15), possible Sjs (n = 96, M/F = 21/75), collagen diseases (CD) (n = 55, M/F = 15/40; 15 SSc, 10 SLE 10, two MCTD, six dermatomyositis, and 22 others), various cutaneous disorders (n = 324, M/F = 118/206), and healthy controls (HC) (n = 50, M/F = 32/18) by using a dermoscope. The average ages of the patients with Sjs, CD (non-Sjs), cutaneous disorders (non-Sjs/CD), and HC were 56.4 14.8, 55.1 116.4, 51.1 121.2, and 37.1 110.6 years of age, respectively. The filiform papillae were classified into four patterns by their structural characteristics: normal papillae (no abnormality with clear cornified tips) (pattern I, n = 162), slightly rounded papillae with unclear cornified tips (pattern II, n = 239), rounded papillae without cornified tips (pattern III, n = 86), and completely flattened papillae (pattern IV, n = 28). Their patterns were reversely related to the volume of salivary fluid (gum test) (P = 0.046) and the degree of furor coating of the tongue (P = 0.051). Pattern IV is predominant in definitive Sjs (primary and secondary Sjs) (n = 15; 53.6%) with positive anti-SS-A or -B antibody (n = 8) with a specificity of 53.6% and a sensitivity of 36.6%. The present dermoscopic finding that the completely flattened pattern (IV) is predominant in definite Sjs patients may indicate a useful marker for suspicion of Sjs.

Age Distribution↗
PubMed1997

Studies of polymorphic DNA fingerprinting and lipid pattern of Mycobacterium tuberculosis patient isolates in Japan.

Strain differentiation by DNA restriction fragment length polymorphism (RFLP) has been used mainly for the epidemiological purpose of Mycobacterium tuberculosis infection. In this study, we tried to connect the molecular and phenotypic characteristics of M. tuberculosis patient isolates by comparing the DNA fingerprints obtained by RFLP using IS6110 and lipid patterns using two-dimensional thin-layer chromatography (2-D TLC) with silica gel, since M. tuberculosis has a lipid-rich cell envelope which contributes to the virulence and immunomodulatory properties. We found that 66 isolates of M. tuberculosis from tuberculosis patients showed that the occurrence of IS6110 varied from 1 to 24 copies. The IS6110 patterns were highly variable among isolates. Fifty different RFLP patterns were observed, and 12 RFLP patterns were shared by two or more strains. By computerized analysis of the RFLP patterns of M. tuberculosis patient isolates, we found that 95% of the isolates fell into seven clusters, from A to G, with at least two isolates in each (> 30% similarity). Among the cellular lipids, the phospholipid composition did not differ by strain, whereas the glycolipid pattern differed markedly. Especially, the relative concentration of cord factor and sulfolipid, both of which were known as virulent factors, varied by strain. The fingerprints of some strains showed an association between the DNA and glycolipid patterns, even though some of the same DNA fingerprint strains showed differences in lipid patterns. Among the patient isolates, M. tuberculosis strain 249 possessed a specific glycolipid with 2-O-methyl-L-rhamnose and L-rhamnose, which is rarely found in other strains. This glycolipid showed serological activity against the sera of tuberculosis patients, even if the reactivity was not as strong as trehalose dimycolate. It also showed the inhibition of phagosome-lysosome fusion in macrophages, suggesting involvement with virulence. These results suggest that RFLP analysis using IS6110 is useful for clustering the human isolates of M. tuberculosis, however, for further strain differentiation on virulence, a lipid analysis provides more information.

Antibodies, Bacterial↗
PubMed2006

Immunodetection of GLUT1, p63 and phospho-histone H1 in invasive head and neck squamous carcinoma: correlation of immunohistochemical staining patterns with keratinization.

Immunodetection of GLUT1, p63 and phospho-histone H1 in invasive head and neck squamous carcinoma: correlation of immunohistochemical staining patterns with keratinizationAims : To examine invasive head and neck squamous carcinomas for expression of GLUT1, a glucose transporter and marker of increased glucose uptake, glycolytic metabolism and response to tissue hypoxia; p63, a p53 homologue that is a marker of the undifferentiated proliferative basaloid phenotype; and phospho-histone H1, a marker of activation of the cell cycle-promoting cyclin-dependent kinases 1 and 2. Methods : Routinely processed slides from 34 invasive squamous carcinomas, including 25 with intraepithelial components, were immunostained with anti-GLUT1 (Chemicon), anti-p63 (4A4, Santa Cruz), and antiphospho-histone H1 (monoclonal 12D11). Results : In keratinizing carcinomas, all three markers were most commonly immunodetected peripherally, with loss of expression in central keratinized zones. In contrast, in non-keratinizing carcinomas, p63 and phospho-histone H1 expression was most commonly observed throughout tumour nests and anti-GLUT1 stained in a pattern suggestive of hypoxia-induced expression ('antistromal' staining), in which cells at the tumour-stromal interface were GLUT1- and cells in central, perinecrotic zones showed progressive induction of GLUT1. Intraepithelial components also displayed basal and 'antibasal' GLUT1 staining patterns, homologous to the pro- and antistromal patterns in invasive carcinoma; basal patterns in intraepithelial lesions appeared to be more predictive of keratinizing invasive carcinoma and antibasal intraepithelial staining more predictive of non-keratinizing poorly differentiated carcinomas. Conclusions : Keratinizing and non-keratinizing squamous carcinomas differ in expression patterns of GLUT1, p63 and phospho-histone H1. In the former, all three markers were typically suppressed in conjunction with keratinization; in the latter, GLUT1 expression was more likely to occur in a hypoxia-inducible pattern and expression of p63 and phospho-histone H1 was unsuppressed. GLUT1 expression patterns in intraepithelial lesions may be predictive of the differentiation status of the associated invasive carcinoma.

Biomarkers, Tumor↗
PubMed1987

Masticatory muscle activity as a function of parafunctional, active and passive oral behavioural patterns.

Oral behavioural patterns have received limited empirical support for their causal role in the development of head and facial pain. The present study was designed to assess electromyographic (EMG) variations in six muscle groups (i.e., bilateral masseter, temporalis and orbicularis oris) as a function of various oral behavioural patterns. A second purpose was to determine whether mandibular movement patterns and specific oral behaviours could be predicted by EMG patterns. Eleven non-pain subjects followed each of twenty oral behavioural patterns while EMG was recorded. Electromyographic change scores were computed for each behaviour relative to baseline measures. Initial analyses were performed using factorial repeated measures ANOVAS. Using post hoc analyses as general guides, specific EMG criteria were developed for classifying mandibular movements. For most subjects, EMG patterns accurately classified teeth clenching, protrusive/retrusive movements, right movements, left movements and lip movement patterns. Wide individual variations were found among muscle groups for identical behaviours. The association between particular oral behaviours and EMG patterns may explain 'sinus' headaches and certain types of facial pain.

Adolescent↗
PubMed1983

Complex cytokeratin polypeptide patterns observed in certain human carcinomas.

Human epithelial cells contain, intermediate-sized filaments formed by polypeptides related to epidermal alpha-keratin ("cytokeratins") which are expressed in different combinations in different epithelia. Using cytoskeletal proteins from human biopsies and autopsies we have examined, by two-dimensional gel electrophoresis and immunoblotting experiments, the cytokeratin polypeptide patterns of diverse primary and metastatic carcinomas and have compared them with those of corresponding normal epithelial tissues and cultured cells. Five groups of carcinoma cytokeratin patterns can be discriminated. (1) Cytokeratins typical of simple epithelia (polypeptides Nos. 7, 8, 18, 19) are expressed, in various combinations, by many adenocarcinomas, for example those of gastrointestinal tract. (2) Cytokeratins typical of stratified epithelia (Nos. 1, 5, 6, 10, 11, 14-17) are found, in various combinations, in squamous cell carcinomas of skin and tongue. (3) Complex patterns showing polypeptides Nos. 7, 8, 18, 19, and one basic component (No. 5 or 6) are detected in certain carcinomas of the respiratory tract and the breast. (4) Complex patterns containing cytokeratins widespread in stratified epithelia (Nos. 4-6, 14-17) as well as components Nos. 8 and 19 occur in diverse squamous cell carcinomas derived from non-cornified stratified epithelia, with or without additional small amounts of cytokeratin No. 18. (5) Patterns of unusually high complexity can be found in some rare tumors as is shown for a cloacogenic carcinoma. No significant qualitative changes of expression of cytokeratins were found when primary tumors and metastases were compared. When compared with cytokeratin patterns of normal epithelia, carcinomas of the first type usually display a high degree of relatedness to the tissue of origin. Other carcinomas do not express some of the cytokeratins present in the tissue of their origin and, vice versa, certain components which are minor or apparently absent in normal tissue are major cytokeratins in the corresponding tumor. These differences may be explained by cell type selection during carcinogenesis, but changes of expression during tumor development cannot be categorically excluded. The possibility of cell type heterogeneity within a given tumor is also discussed. Similarly complex patterns of cytokeratin polypeptides have been noted in certain cultured human carcinoma cell lines (e.g., A-431, RPMI 2650, Detroit 562, A-549) and can also be observed in cell clones. The possible value of analyses of cytokeratin patterns, by gel electrophoresis or specific monoclonal antibodies, in distinguishing different carcinomas by non-morphologic criteria is discussed.

Breast Neoplasms↗
PubMed2005

Patterned firing of parietal cells in a haptic working memory task.

Abstract Cells in the somatosensory cortex of the monkey are known to exhibit sustained elevations of firing frequency during the short-term mnemonic retention of tactile information in a haptic delay task. In this study, we examine the possibility that those firing elevations are accompanied by changes in firing pattern. Patterns are identified by the application of a pattern-searching algorithm to the interspike intervals of spike trains. By sequential use of sets of pattern templates with a range of temporal resolutions, we find patterned activity in the majority of the cells investigated. In general, the degree of patterning significantly increases during active memory. Surrogate analysis suggests that the observed patterns may not be simple linear stochastic functions of instantaneous or average firing frequency. Therefore, during the active retention of a memorandum, the activity of a 'memory cell' may be characterized not only by changes in frequency but also by changes in pattern.

Action Potentials↗
PubMed1984

Fetal heart rate patterns and perinatal outcome of very-low-birthweight infants.

The obstetric records of 125 infants weighing 500-1250 g who were born in 1978 and 1979 at the Helsinki University Central Hospital were studied retrospectively to find out any associations between fetal heart rate (FHR) patterns and perinatal outcome. FHR recordings of 79 fetuses were available for study. Normal reactive patterns were observed in nine, nonreactive in 54, decelerations in 58, silent patterns in 45 and combined distress patterns in 36 fetuses. The interval from the first pathological sign to delivery was up to 27 days. Five fetuses in the monitored group died in utero, 26 infants died neonatally and two later. The risk of neonatal death after pathological FHR patterns was lower than after an FHR pattern without abnormality. Idiopathic respiratory distress syndrome (RDS) was diagnosed in 32 infants, of whom 16 died. Forty-seven fetuses (59%) of the monitored group were delivered abdominally and 32 vaginally. The risk of RDS was not significantly associated with FHR patterns and mode of delivery. We conclude that unlike term fetuses, low-birthweight fetuses seem to benefit from a period of intrauterine stress reflected in abnormal FHR patterns, if caesarean section is used liberally.

Birth Weight↗
PubMed1995

The velocity distribution in the aortic annulus at different times during systole is mainly determined by the pattern of flow convergence in the left ventricular outflow tract--an experimental study using Doppler colour flow mapping.

An experimental study in 10 open chest normal pigs (body weight: 24 +/- 1 kg) was carried out to explore the relationship between the velocity distribution in the aortic annulus and the pattern of flow convergence in the left ventricular outflow tract. The cross-sectional velocity profiles in the aortic annulus were constructed by using Doppler colour flow mapping with a previously validated time-interpolation method. The pattern of flow convergence in the left ventricular outflow tract was quantified by measuring the colour flow areas on the anterior and posterior sides of the central axis of the aortic annulus, and calculating their difference. The dynamic changes of the velocity distribution, the pattern of flow convergence and the septal angle throughout systole were observed. The velocity distribution in the aortic annulus changed according to the pattern of flow convergence in the left ventricular outflow tract. During early systole, the pattern of flow convergence was most asymmetrical. With the central longitudinal axis of the aortic annulus as a reference, the main part of the converging flow was along the anterior wall of the left ventricular outflow tract. Consequently, the velocity profile in the aortic annulus was most skewed during the early systole, with the highest velocity along the anterior wall. Towards late systole, the pattern of flow convergence became more and more symmetrical, and the velocity distribution in the aortic annulus gradually became flat. A significant correlation was found between the extent of asymmetry of the pattern of flow convergence in the left ventricular outflow tract and the extent of skewness of the velocity distribution in the aortic annulus (r = 0.69, P < 0.001). Throughout systole, septal angle increased very slightly (from 35 +/- 3 to 38 +/- 3 degrees, P < 0.01). The pattern of flow convergence in the left ventricular outflow tract is a major determinant of the velocity distribution in the aortic annulus in pigs.

Animals↗
PubMed2005

Impact of diabetic nephropathy and angiotensin II receptor blockade on urinary polypeptide patterns.

BACKGROUND: New insights into the pathogenesis and treatment of diabetic renal disease may emerge from recent advances in proteomics using high-throughput mass spectrometry (MS) of urine. METHODS: Using a combination of online capillary electrophoresis (CE) and MS we evaluated urinary polypeptide patterns in four groups of type 2 diabetic patients matched for age, gender, and diabetes duration, including 20 normoalbuminuric patients with and 20 without diabetic retinopathy, 20 microalbuminuric patients with diabetic retinopathy, and 18 macroalbuminuric patients with diabetic retinopathy. Furthermore, changes in urinary polypeptide patterns during treatment with the angiotensin II receptor blocker (ARB) candesartan were evaluated in the macroalbuminuric patients in a randomized double-blinded, cross-over trial where each patient received treatment with placebo, candesartan 8, 16, and 32 mg daily each for 2 months. RESULTS: Overall, 4551 different polypeptides were found in the samples. Urinary polypeptide patterns were comparable in normo- (with and without diabetic retinopathy) and microalbuminuric patients, whereas distinct differences were found in macroalbuminuric patients. Differences in urinary polypeptide patterns between normo- and macroalbuminuric patients permitted the establishment of a "diabetic renal damage" pattern consisting of 113 polypeptides. Eleven of these polypeptides had been sequenced and identified. Candesartan treatment in macroalbuminuric patients significantly changed 15 of the 113 polypeptides in the diabetic renal damage pattern toward levels in normoalbuminuric patients. Change in the diabetic renal damage pattern was not candesartan dose-dependent but individual changes correlated with changes in urinary albumin excretion at each dose level. CONCLUSION: CE-MS serves as a fast and sensitive tool for identification of biomarkers and urinary polypeptide patterns specific for macroalbuminuric type 2 diabetic patients and may be used to explore and monitor renoprotective effects of ARB.

Albuminuria↗
PubMedDate not supplied

Jumping genes and AFLP maps: transforming lepidopteran color pattern genetics.

The color patterns on the wings of lepidopterans are among the most striking patterns in nature and have inspired diverse biological hypotheses such as the ecological role of aposomatic coloration, the evolution of mimicry, the role of human activities in industrial melanism, and the developmental basis of phenotypic plasticity. Yet, the developmental mechanisms underlying color pattern development are not well understood for three reasons. First, few mutations that alter color patterns have been characterized at the molecular level, so there is little mechanistic understanding of how mutant phenotypes are produced. Second, although gene expression patterns resembling adult color patterns are suggestive, there are few data available showing that gene products have a functional role in color pattern formation. Finally, because with few exceptions (notably Bombyx), genetic maps for most species of Lepidoptera are rudimentary or nonexistent, it is very difficult to characterize spontaneous mutants or to determine whether mutations with similar phenotypes are because of lesions in the same gene or different genes. Discussed here are two strategies for overcoming these difficulties: germ-line transformation of lepidopteran species using transposon vectors and amplified frequency length polymorphism-based genetic mapping using variation between divergent strains within a species or between closely related and interfertile species. These advances, taken together, will create new opportunities for the characterization of existing genetic variants, the creation of new sequence-tagged mutants, and the testing of proposed functional genetic relationships between gene products, and will greatly facilitate our understanding of the evolution and development of lepidopteran color patterns.

Animals↗
PubMed2005

Time-series features of headache: individual distributions, patterns, and predictability of pain.

OBJECTIVE: This preliminary study employed "within-patient" time-series methodology to examine headache symptom distributions (peak, sum) to assess predictability of day-to-day headache based on overall pattern, and to better characterize distributional properties of headache as they relate to study design and statistics in future research. BACKGROUND: Headache symptoms for a given patient may vary widely from one day to the next, ranging from days when the headache sufferer is asymptomatic to days when he or she is functionally disabled with severe headache. Although day-to-day variations are well recognized and appreciated clinically, headache is seldom studied using daily (eg, time-series) methodology that can elucidate potentially important individual and temporal variations. Instead, most headache research has relied upon cross-sectional designs aimed at examining group rather than individual effects which may serve to mask important individual differences. Additional within-patient time-series studies are needed to help identify symptom patterns, clinically meaningful patient subgroups, and relationships among precipitants, interventions, and outcomes. Such research would be aided by delineation of the distributional and temporal properties of key scales (eg, daily headache peak, sum). The present research provides such information derived from clinical samples of migraine and tension-type headache sufferers, laying a foundation for future time-series research. METHODS: Twenty-five migraine and 24 tension-type headache sufferers prospectively recorded daily headache activity for 1 month. Individual headache distributions were generated and examined individually and by diagnostic group. Predictability for headache was analyzed case by case and summarized by diagnostic group. RESULTS: The study determined the degree to which individual patients' headache activity distributions deviate from normality (skewness, kurtosis). For migraine and tension-type headache, individual patients' headache patterns were distinctly bimodal in nature. Notably, headache patterns with the lowest frequency were the most bimodal, and as frequency increased, the distributions tended to more closely approximate normal. Patterns were also detailed according to measures of predictability for headache (trends, autocorrelation). Generally, headache days tended to cluster together for both tension-type and migraine (positive autocorrelation) with headache on day 1 being a good predictor of headache on day 2. CONCLUSIONS: To the authors' knowledge, this is the first study to utilize time-series methodology to characterize individual patients' headache distributions and temporal patterns and to empirically address predictability in this manner. The bimodal distributions noted among less frequent headache patterns would suggest that basic assumptions underlying the use of inferential statistics may be violated when examining intra-individual relationships. Time-series research promises to yield unique insights into patterns, precipitants, and impact of headache disorders, but future research must address both the large degree of individual differences in headache and the account for the unique types of statistical distributions among individual headache sufferers.

Adult↗
PubMedDate not supplied

The effect of tension on perfusion of axial and random pattern flaps in foals.

Caudally based axial pattern and random pattern skin flaps, 5 cm x 10 cm, were raised on the abdomens of seven foals. Blood flow was measured 7.5 cm from the flap bases during incremental increases in applied tension. At tensions less than 1400 g, cutaneous blood flow was more than four times higher in axial pattern flaps than in random pattern flaps. Blood flow in axial pattern flaps at tensions up to 1500 g was greater than baseline flow in random pattern flaps. After removal of applied tension, perfusion in axial pattern flaps gradually increased but remained below baseline values. A short period of hyperperfusion after removal of tension in random pattern flaps may have been indicative of accumulation of waste products and localized acidosis. All flaps healed in their donor beds without complications.

Animals↗
PubMed2006

Buried tension sutures: force-tension comparisons of pulley, double butterfly, mattress, and simple interrupted suture patterns.

OBJECTIVES: To compare suture patterns (simple interrupted, modified pulley, horizontal mattress, double butterfly) by use of a novel in vitro model that quantifies force required for closure against tension. STUDY DESIGN: In vitro study. SAMPLE POPULATION: Suture constructs. METHODS: An in vitro suturing frame was constructed with extension springs to provide a standard resistance against movement of 2 panels of loops toward each other. Four different suture patterns were applied to the frame in randomized trials. The frame was affixed to a tensiometer that measured the force required for each suture pattern to close a fixed distance (3.81 cm) at a constant rate (5.08 cm/min) against the tension (0.6 kg/cm) of the extension springs. The closure distance and tension were selected subjectively to mimic tension encountered clinically during wound reconstruction oncologic surgical procedures. RESULTS: The modified pulley suture required the least force to close, followed by the double butterfly, simple interrupted, and horizontal mattress patterns. CONCLUSIONS: The modified pulley suture and double butterfly suture patterns require less force to close a given distance under tension than either simple interrupted or horizontal mattress suture patterns. CLINICAL RELEVANCE: Application of tension relieving suture techniques for fascia, subcutaneous, and buried-knot subdermal suturing should be considered to facilitate direct closure of wounds under tension. Modified pulley and double butterfly suture patterns offer some mechanical advantage by requiring less force to achieve closure compared with other suture patterns that might be used in reconstructive surgery.

Animals↗
PubMed1996

Salivary mutans streptococci and dental caries patterns in pre-school children.

Recent studies have suggested that the identification of caries as discrete patterns may be valuable in describing and predicting caries experience on an individual basis. The purpose of this study was to assess the association between levels of salivary mutans streptococci and the prevalence, incidence and distribution of caries patterns in the primary dentition. A cohort of pre-school children (n = 146, mean age 3.8 yr) were examined for dental caries and sampled for salivary mutans streptococci (SMS) at baseline and once annually for 2 yr. Children's tooth surfaces were categorized into four patterns: pit/fissure, maxillary anterior, posterior proximal, and buccal/lingual smooth surface. Salivary mutans streptococci were enumerated using a tongue blade technique, and were categorized as low (0 CFU), moderate (1-50 CFU) and high (> 50 CFU). At year 2, children with high baseline SMS had the 1) highest prevalence of caries (87%) and the highest dmfs (9.15); 2) highest prevalence of each pattern, and 3) greatest number of patterns. Among children with the pit/fissure pattern, those with high baseline SMS had the greatest pit/fissure dmfs after 2 yr. Results show that baseline SMS levels were associated with both cross-sectional and longitudinal caries experience, numbers of caries patterns, and the prevalence and severity of those patterns.

Child, Preschool↗
PubMed1995

Identification of latent myeloproliferative disease in patients with Budd-Chiari syndrome using X-chromosome inactivation patterns and in vitro erythroid colony formation.

Some patients with an early or latent myeloproliferative disorder (MPD) present with Budd-Chiari syndrome (BCS, hepatic vein thrombosis). Cell culture analysis of erythroid progenitors (BFU-E) can be used to discriminate primary from secondary MPD and examination of X-chromosome inactivation (in females) can be used to demonstrate clonality in neoplastic tissues. The present study used these techniques to examine whether a group of 7 female patients who presented with BCS had evidence to support a diagnosis of MPD. Unilateral X-inactivation and therefore clonality can be studied in females heterozygous for X-linked restriction fragment length polymorphisms (RFLP) by differences in methylation between active and inactive chromosomes. Probes for two polymorphic loci, phosphoglycerate kinase (PGK, at Xq13.3 [BstX1 RFLP]) and M27 beta (an anonymous locus DXS255 at Xp11.22 [Pst1 RFLP]) were used to study methylation patterns. All 7 patients were heterozygous using M27 beta and 2/7 were also heterozygous using the PGK probe. Polyclonal patterns of X-inactivation in granulocytes were demonstrated in 3/7, a skewed/monoclonal pattern in 1/7 and aberrant patterns in 3/7 using M27 beta. Two patients who had aberrant patterns of X inactivation with M27 beta demonstrated a skewed/monoclonal pattern with PGK. The results of BFU-E growth patterns and clonality were entirely concordant in 5/6 patients. Thus X-chromosome inactivation patterns, in conjunction with erythroid colony studies, can be used to assist in the diagnosis of an underlying MPD in BCS.

Biomarkers↗
PubMed1991

Flashed pattern-induced activity in the visual system: I. The short latency evoked response recorded from the cat visual cortex.

Previous methods for estimating visual acuity have used the visual evoked response conventionally the late visual evoked response components or the steady-state potential. The present experiments were undertaken to evaluate the possible use of short latency flashed pattern evoked responses in estimating pattern dependent activity in the cat visual system. Recordings were made from the skull bone and the dura above the primary visual cortex and intracortically. The visual evoked responses to patterned (checks) and non-patterned light flashes of high intensity and short duration were recorded. The visual evoked response activity recorded from the cortical surface had an onset latency of 14-15 ms. The initial positive-negative potential sequences of the responses were similar for patterned and non-patterned stimuli, however a difference was recorded from 35-40 ms after stimulus. The smallest check size which separated a pattern from a non-pattern VER was in the order of 10 min of arc. The results indicate that the short-latency cortical VER may be used to estimate visual resolution.

Animals↗
PubMed2003

Vascular patterns in glioblastoma influence clinical outcome and associate with variable expression of angiogenic proteins: evidence for distinct angiogenic subtypes.

No data exist on angiogenic patterns and their prognostic impact in human glioblastoma. Such data are relevant for translation of antiangiogenic therapies into clinical applications. Using immunohistochemistry for CD34, we assessed vascular patterns in 114 primary glioblastomas. Vascular patterns comprised unevenly distributed glomeruloid/garland-like/clustered bizarre vascular formations and evenly distributed delicate capillary-like microvessels ("classic" vascular pattern). The combination of low content of bizarre vascular formations and prominent classic vascular pattern (n=29) was an independent factor for longer survival (p=0.006, Cox regression), as well as postoperative high Karnofsky performance status (p=0.005). In patients with a prominent classic vascular pattern, there was no difference of MIB1 labeling index whereas microvessel density and apoptotic index (TUNEL) were significantly higher as compared to all other patients (p<0.05). In addition, diffuse expression of hypoxia-inducible factor (HIF)-1alpha and strong expression of vascular endothelial growth factor were more common (p<0.05, Chi-square test). FISH revealed loss of chromosomes 1p and 19q only in 1/7 long-time survivors with classic pattern. We conclude that vascular patterns in primary glioblastoma influence clinical outcome and associate with variable expression of angiogenic proteins. Our findings denote for the first time distinct angiogenic subtypes of human glioblastoma which may prove relevant for anti-angiogenic therapy approaches.

Adult↗
PubMed1985

Tactile pattern perception and its perturbations.

One of the problems encountered in conveying information to the skin by means of vibratory patterns is that presenting patterns, such as letters of the alphabet, in close spatial and temporal proximity, may result in considerable masking. Generally, there is more interference when the masking stimulus follows the target (backward masking) than when it precedes it (forward masking). Masking has also been demonstrated with vibrotactile patterns derived from speech signals. Masking may be reduced by increasing the temporal and spatial separation between patterns; however, other problems may arise when such separations are made. Because stimulus onset asynchrony appears to be the critical temporal dimension for masking, it may prove difficult to reduce masking by increasing the temporal separation between patterns without also reducing the rate at which the patterns are presented. Increasing the spatial separation between patterns may lead to problems in combining the patterns from spatially distinct sites on the skin. This latter difficulty may be due to problems in attending to several sites of stimulation simultaneously.

Attention↗