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PubMedDate not supplied

Biochemical signaling networks decode temporal patterns of synaptic input.

Synapses exhibit a wide repertoire of responses to different temporal patterns of synaptic input. Many of these responses are expressed as short and long-term changes in synaptic strength. Electrical properties of channels and calcium buildup can account for rapid aspects of pattern decoding, but it is not clear how more complex input patterns, especially those lasting over many minutes, could be discriminated. This paper shows that a network of signaling pathways can discriminate between complex input patterns lasting tens of minutes, and can give rise to distinct combinatorial patterns of biochemical signaling activity in pathways involved in synaptic change. Regulatory signaling input can alter and even reverse the strengths of responses to input patterns. Thus the synaptic signaling network may function as a temporal decoder that transforms patterns from the time domain into the domain of chemical signaling. This may underlie different synaptic responses to different stimulus patterns.

Calcium↗
PubMed2000

Dynamic topography of pattern visual evoked potentials (PVEP) in psychogenic visual loss patients.

We investigated to measure the objective visual acuity using pattern visual evoked potentials (PVEP) to help the diagnosis with psychogenic visual loss (PVL) who ranged in age from 7 to 14 years old. Pattern stimuli consisted of black and white checkerboard patterns (39, 26, 15 and 9') with a visual angle of 8 degrees and a contrast level of 15%. The pattern reversal frequency was 0.7 Hz. This resulted in an average of 100 PVEP per session. Visual acuity of 0.1 was consistent with the 39' pattern, 0.2 with the 26' pattern, 0.5 with the 15' pattern, and 1.0 with the 9' pattern. As the results, five PVL patients could measure visual acuity with this method in the present study. The PVEP is useful in evaluating the visual acuity and helped to diagnose the PVL patients. In addition we used the dynamic topography to study the difference in the results of the PVEP. The dynamic topography obtained from the results of the PVEP was analyzed. The flow type of the P100 component diverged into three types (separated type, hollow type and localized type) in the PVL patients and the normal children. The localized type was observed in 59.1% of normal children and in 56.3% of PVL patients. While the separated type was shown in 6.8% of normal children and in 8.3% of PVL patients. There were not significant differences between the PVL patients and the normal children in each type.

Adolescent↗
PubMed2004

Impact of flow level on coronary flow velocity pattern. A doppler flow study in patients with first acute myocardial infarction.

Analysis of coronary flow velocity pattern has been used to assess microvascular function post acute myocardial infarction (AMI). This study sought to analyze whether the flow level has an impact on parameters of coronary flow velocity pattern. Parameters of coronary flow velocity pattern were determined at baseline and during increased flow due to maximal hyperemia induced by adenosine in 25 patients after PTCA for first AMI using Doppler flow wires. Patients were divided into those with depressed (global wall motion index (GWMI) > or = 1.5; n = 14) and those with preserved (GWMI < 1.5; n = 11) left ventricular (LV) function at 4 weeks. Coronary flow velocity pattern at rest was different between patients with depressed and patients with preserved LV function at follow-up. A difference in flow pattern between the groups remained at increased flow level. However, increase of flow altered parameters of flow pattern. Diastolic deceleration rate (DSR) increased for patients with preserved LV function (53.7+/-25.6 at baseline vs. 67.0+/-29.8 cm/s2 with adenosine) and depressed LV function (95.3+/-58.6 vs. 110.7+/-61.4 cm/s2, respectively, p = 0.0012). Induction of hyperemia resulted also in increased systolic and diastolic peak flow velocity and diastolic deceleration time (DDT). Higher flow had no impact on early systolic retrograde flow, systolic flow duration and diastolic-systolic velocity ratio (DSVR). The coronary flow velocity pattern allows prediction of LV function at 4 weeks after AMI. However, it should be considered that some parameters of the flow velocity pattern are affected by the coronary flow level.

Acute Disease↗
PubMed2002

Identifying criterion-related patterns of predictor scores using multiple regression.

Along with examples involving vocational interests and mathematics achievement, the authors describe a multiple regression based, pattern recognition procedure that can be used to identify a pattern of predictor scores associated with high scores on a criterion variable. This pattern is called the criterion pattern. After the criterion pattern has been identified, a second regression procedure can be used to estimate the proportion of variation attributable to the criterion pattern. Cross-validation can then be used to estimate the variation attributable to a criterion pattern derived from regression weights estimated in another sample. Finally, issues of criterion pattern invariance and interpretation are discussed.

Achievement↗
PubMed2003

Repeated-measures contrasts for "multiple-pattern" hypotheses.

Contrast analysis of repeated-measures data generally focuses on hypotheses when only 1 pattern of results is of theoretical interest. This article articulates a framework for contrast analysis in repeated-measures contexts in which researchers have hypotheses relevant to 1 potential pattern or multiple potential patterns of results. For example, a researcher might ask whether participants exhibit a pattern of (a) immediate symptom reduction or (b) delayed symptom reduction. Alternatively, the researcher might ask whether 2 or more groups exhibit 2 or more patterns to differing degrees. Building on the familiar logic and computational procedures for 1-pattern hypotheses, the authors present a contrast analysis framework that integrates analysis of 1-pattern and multiple-pattern hypotheses and accommodates 1 group or multiple groups of participants.

Humans↗
PubMed1998

Transduction of temporal patterns by single neurons.

As our ability to communicate by Morse code illustrates, nervous systems can produce motor outputs, and identify sensory inputs, based on temporal patterning alone. Although this ability is central to a wide range of sensory and motor tasks, the ways in which nervous systems represent temporal patterns are not well understood. I show here that individual neurons of the lobster pyloric network can integrate rhythmic patterned input over the long times (hundreds of milliseconds) characteristic of many behaviorally relevant patterns, and that their firing delays vary as a graded function of the pattern's temporal character. These neurons directly transduce temporal patterns into a neural code, and constitute a novel biological substrate for temporal pattern detection and production. The combined activities of several such neurons can encode simple rhythmic patterns, and I provide a model illustrating how this could be achieved.

Animals↗
PubMed1987

Collagen IV staining pattern in bladder carcinomas: relationship to prognosis.

A prospective study of type IV collagen in urothelial tissues was undertaken using an immunoperoxidase method on 125 ethanol fixed specimens. In normal and non cancerous urothelium, the basement membrane was continuously stained and the same pattern was seen in the 27 superficial carcinomas. In the 48 invasive bladder carcinomas, we observed two patterns of staining for collagen IV: in the first one, the staining line was conserved or partially fragmented (28 tumours), while in the second one the staining line was widely fragmented or absent in more than 5% of the tumour area (20 tumours). We found a highly significant statistical correlation between the pattern of staining and short term prognosis. Twenty-nine patients had an assessable follow-up of three years at least. All 16 patients with pattern I staining were alive at two years while only two out of 13 patients with pattern II staining survived two years (P less than 0.0001). At three years, all the patients with pattern II staining died while 11 patients with pattern I were still alive (P less than 0.001). These data provisionally indicate that the type IV collagen staining pattern may be of prognostic value in assessing the short term behaviour of invasive bladder carcinomas. It is thus logical to envisage that the treatment decisions may be influenced by the results of collagen IV staining.

Basement Membrane↗
PubMed1998

Vascular endothelial growth factor (VEGF) mRNA isoform expression pattern is correlated with liver metastasis and poor prognosis in colon cancer.

Vascular endothelial growth factor (VEGF) is a well known factor that induces angiogenesis. Four isoforms, i.e. VEGF206, 189, 165, and 121, have been identified. We examined the isoform patterns of VEGF mRNA using reverse transcription polymerase chain reaction (RT-PCR) analysis in 61 colon cancers. All the colon cancers examined expressed VEGF121. The isoform patterns were classified into three groups: type 1, VEGF121; type 2, VEGF121 + VEGF165; type 3, VEGF121 + VEGF165 + VEGF189. Three of the 61 colon cancers examined showed type 1 expression, 26 showed type 2 expression and 32 showed the type 3 pattern. The patients with liver metastases showed the type 3 isoform expression pattern at a significantly higher incidence (12 of 16, 75%) than those without liver metastasis (20 of 45, 44%) (P=0.036). The type 3 isoform pattern was significantly associated with M1 stage (P=0.019). The patients with colon cancer and the type 3 isoform pattern showed significantly poor prognosis (P < 0.01, Cox-Mantel). The colon cancers with the type 3 pattern showed a significantly higher involvement of veins (P=0.006). These observations suggest that the aberrant type 3 expression pattern of VEGF189 mRNA isoforms is correlated with liver metastasis, M stage, and poor prognosis in colon cancer.

Adenocarcinoma↗
PubMed2006

Prevalence of horizontal deviation pattern changes with measurements in extreme gazes.

PURPOSE: To analyse the difference between measurement of A and V pattern strabismus at 25 degrees and extreme gaze position in esotropia (ET) and exotropia (XT). METHODS: This prospective cross-section study included 27 patients with basic horizontal strabismus associated to any deviation pattern. Mean age was 11.88+/-9.17 (6-44) years. Exclusion criteria were amblyopia, intermittent XT, noncollaboration with the exam, previous strabismus surgery, craniofacial, or spinal abnormalities. The deviations were measured with prism cover test at 6 m. Measurements were carried out in primary position, upgaze (neck flexion of 25 degrees and maximum flexion) and downgaze (neck extension of 25 degrees and maximum extension). A goniometer with a bubble level controlled the neck position. RESULTS: The most significant changes were in downgaze. The pattern size increased 4 prism dioptres (PD) or more in 56.25% of the V- and in 87.5% of the A-patterns. The mean increase was 8.00+/-6.04 PD (0-17 PD) for the A-pattern ET, 4.80+/-3.70 PD (0-10 PD) for the V-pattern XT, and 6.50+/-5.58 PD (0-15 PD) for the V-pattern XT. The only case of A-pattern XT increased 8 PD. CONCLUSION: Our results suggest that measurements in extreme up and downgazes may uncover increased deviations in a significant proportion of cases. Further studies remain necessary to determine the relevance of these findings for strabismus correction.

Adolescent↗
PubMed2006

Indoor time-microenvironment-activity patterns in seven regions of Europe.

Personal exposure to environmental substances is largely determined by time-microenvironment-activity patterns while moving across locations or microenvironments. Therefore, time-microenvironment-activity data are particularly useful in modeling exposure. We investigated determinants of workday time-microenvironment-activity patterns of the adult urban population in seven European cities. The EXPOLIS study assessed workday time-microenvironment-activity patterns among a total of 1427 subjects (age 19-60 years) in Helsinki (Finland), Athens (Greece), Basel (Switzerland), Grenoble (France), Milan (Italy), Prague (Czech Republic), and Oxford (UK). Subjects completed time-microenvironment-activity diaries during two working days. We present time spent indoors--at home, at work, and elsewhere, and time exposed to tobacco smoke indoors for all cities. The contribution of sociodemographic factors has been assessed using regression models. More than 90% of the variance in indoor time-microenvironment-activity patterns originated from differences between and within subjects rather than between cities. The most common factors that were associated with indoor time-microenvironment-activity patterns, with similar contributions in all cities, were the specific work status, employment status, whether the participants were living alone, and whether the participants had children at home. Gender and season were associated with indoor time-microenvironment-activity patterns as well but the effects were rather heterogeneous across the seven cities. Exposure to second-hand tobacco smoke differed substantially across these cities. The heterogeneity of these factors across cities may reflect city-specific characteristics but selection biases in the sampled local populations may also explain part of the findings. Determinants of time-microenvironment-activity patterns need to be taken into account in exposure assessment, epidemiological analyses, exposure simulations, as well as in the development of preventive strategies that focus on time-microenvironment-activity patterns that ultimately determine exposures.

Activities of Daily Living↗
PubMed2006

Environmental and occupational exposures and serum PCB concentrations and patterns among Mohawk men at Akwesasne.

A study was conducted to address the question of how fish consumption, occupation, and outdoor air affected serum PCB concentrations and congener patterns among 139 Native American men living near three hazardous waste sites. They were interviewed about their residential, occupational, and dietary histories, and donated 20 ml of venous blood for congener-specific PCB analysis. The similarity in the congener pattern between that found in the serum and that detected in local environmental samples was measured by calculating the Euclidean distance between them. The results indicated that serum PCB concentrations were positively associated with cumulative lifetime exposures to PCBs from local fish consumption and occupation. However, participants who lived in the last 10 years at Raquette Point, which is the area of the Reserve closest to the hazardous waste sites and the only location where elevated levels of PCBs were found in outdoor air, did not have higher serum PCB concentrations than participants who lived elsewhere at Akwesasne. Regarding pattern matching, Mohawk men with the greatest cumulative lifetime exposure to PCBs from local fish consumption had a serum PCB congener pattern that more closely resembled that in fish caught off-shore from one of the hazardous waste sites than did men who ate less local fish. Similarly, Mohawk men who were occupationally exposed to PCBs were more likely than those without occupational exposure to have a serum PCB congener pattern that was similar to that of Aroclor 1248, the commercial PCB mixture used locally. The serum PCB congener pattern of Raquette Point residents more closely resembled the pattern in outdoor air only if the men ate relatively few local fish. The study is among the first to demonstrate that outdoor air may affect serum PCB congener patterns, at least in the absence of heavy fish consumption.

Adolescent↗
PubMed2006

Rapid heterogeneous liver-cell on-chip patterning via the enhanced field-induced dielectrophoresis trap.

Biomimetic heterogeneous patterning of hepatic and endothelial cells, which start from randomly distributed cells inside the microfluidic chamber, via the chip design of enhanced field-induced dielectrophoresis (DEP) trap is demonstrated and reported in this paper. The concentric-stellate-tip electrode array design in this chip generates radial-pattern electric fields for the DEP manipulation of the live liver cells. By constructing the geometric shape and the distribution of stellate tips, the DEP electrodes enhance the desired spatial electric-field gradients to guide and snare individual cells to form the desired biomimetic pattern. With this proposed microfluidic chip design, the original randomly distributed hepatocytes inside the microfluidic chamber can be manipulated in parallel and align into the desired pearl-chain array pattern. This radial pattern mimics the lobular morphology of real liver tissue. The endothelial cells, then, are snared into the additional pearl-chain array and settle at the space in-between the previous hepatic pearl-chain array. By this cell-lab chip, we demonstrate the in vitro reconstruction of the heterogeneous lobule-mimetic radial pattern with good cell viability after cell patterning. This work reports the rapid in-parallel patterning of the dual types of live liver cells via the enhanced DEP trap inside the microfluidic chip.

Biomimetic Materials↗
PubMed1997

Magnetic resonance imaging patterns in patients with multiple myeloma.

Sixty-one consecutive patients with multiple myeloma were studied with magnetic resonance (MR) imaging of the spine. Sagittal T1-weighted and short inversion time (TI) inversion recovery (STIR) images were obtained. The MR patterns of the bone marrow were classified as diffuse (D) (n=26), nodular (N) (n=11), D+N (n=13) or normal (n) (n=11). Abnormal patterns were seen in 50 (82%) of the 61 patients. Correlations were found between the MR imaging patterns and some laboratory findings (WBC, haematocrit, platelet count, serum albumin, and percentage of marrow plasmacytosis). The survival of the patients with abnormal MRI patterns was significantly poorer than that of the patients with normal patterns. However, the survival of patients with a nodular pattern did not differ from those with a normal pattern. The MR imaging pattern of the bone marrow in patients with multiple myeloma is a useful factor in the assessment of prognosis.

Adult↗
PubMed2000

Pattern recognition as a caring partnership in families with cancer.

Pattern recognition as a caring partnership in families with cancer The purpose of this study was to address the process of a caring partnership by elaborating pattern recognition as nursing intervention with families with cancer. It is based on Newman's theory of health as expanding consciousness within the unitary-transformative paradigm and is an extension of a previous study of Japanese women with ovarian cancer. A hermeneutic, dialectic method was used to engage 10 Japanese families in which the wife-mothers were hospitalized because of cancer diagnosis. The family included at least the woman with cancer and her primary caregiver. Each of four nurse-researchers entered into partnership with a different family and conducted three interviews with each family. The participants were asked to describe the meaningful persons and events in their family history. The family's story was transmuted into a diagram of sequential patterns of interactional configurations and shared with the family at the second meeting. Evidence of pattern recognition and insight into the meaning of the family pattern were identified further in the remaining meetings. The data revealed five dimensions of a transformative process. Most families found meaning in their patterns and made a shift from separated individuals within the family to trustful caring relationships. One-third of them went through this process within two interviews. The families showed increasing openness, connectedness and trustfulness in caring relationships. In partnership with the family, each nurse-researcher grasped the pattern of the family as a whole and experienced the meaning of caring. Pattern recognition as nursing intervention was a meaning-making transforming process in the family-nurse partnership.

Adaptation, Psychological↗
PubMed1997

The association of pattern of maternal weight gain with length of gestation and risk of spontaneous preterm delivery.

Monitoring weight gain during pregnancy may be useful in detecting pregnancies that are at increased risk of early delivery. This study examines 7259 deliveries that occurred at the University of California, San Francisco's Moffitt Hospital from 1980 to 1990. Obese women, women with diabetes or hypertension during pregnancy, deliveries with congenital malformations and non-spontaneous preterm deliveries were excluded. Pattern of gain was assessed by fitting a quadratic curve to each woman's series of weight and date measurements, using simple regression techniques. The parameters from this curve were used to develop a variable for pattern of gain that reflects how much an individual's pattern of gain differs from a linear pattern of gain. Multivariable linear and logistic regression analyses indicate that patterns of gain that deviate greatly from the average pattern of gain (i.e. patterns that show a marked speeding up or slowing down of gain towards the end of pregnancy) are associated with significantly shorter gestational age and confer a significantly increased risk of spontaneous preterm delivery. The results suggest that monitoring weight gain during pregnancy is important, although more specific studies are needed to understand the mechanisms by which weight gain pattern relates to preterm delivery before appropriate interventions can be developed.

Adult↗
PubMed2003

Angelman syndrome: difficulties in EEG pattern recognition and possible misinterpretations.

PURPOSE: This study aimed to evaluate the sensitivity of the EEG in Angelman syndrome (AS), to verify the age at onset of suggestive EEGs and to study EEG patterns, analyzing variations and comparing our findings with nomenclature previously used. METHODS: Seventy EEG and 15 V-EEGs of 26 patients were analyzed. Suggestive EEG patterns of AS were classified in delta pattern (DP), theta pattern (TP), and posterior discharges (PDs). Generic terms were used to simplify the analysis. RESULTS: Suggestive EEGs were observed in 25 (96.2%) patients. DP occurred in 22 patients with four variants-hypsarrhythmic-like: irregular, high-amplitude, generalized delta activity (DA) with multifocal epileptiform discharges (EDs); slow variant: regular, high-amplitude, generalized DA with rare EDs; ill-defined slow spike-and-wave: regular, high-amplitude, generalized DA with superimposed EDs characterizing a slow wave, with notched appearance; triphasic-like: rhythmic, moderate-amplitude DA over anterior regions with superimposed EDs. TP was observed in eight patients, as generalized or over the posterior regions. PDs were seen in 19 patients as runs of sharp waves or runs of high-amplitude slow waves with superimposed EDs. TP was the only age-related pattern (younger than 8 years) and observed only in patients with deletion. In 15 patients who had an EEG before the clinical diagnosis, 60% had a suggestive tracing. CONCLUSIONS: Although some EEG descriptions are not very detailed, and every author describes findings in a slightly different manner, obviously a common denominator must exist. In this context, EEG seems to be a very sensitive method for the diagnosis of AS, offering an opportunity to corroborate this etiologic diagnosis. Conversely, we do not believe that these patterns may be accounted as specific, except for the delta pattern, which seems to be extremely unusual in other syndromes. Other EEG patterns observed in AS, such as theta activity and PDs, occur in a wide variety of disorders. Nonetheless, their importance for the EEG diagnosis of AS is supported by the fact that they are associated with other features and may be helpful in a proper clinical setting.

Adolescent↗
PubMed2000

High risk mammographic parenchymal patterns and diet: a case-control study.

Mammographic parenchymal patterns are related to breast cancer risk and are also thought to be affected by diet. We designed a case-control study comprising 200 cases with high-risk (P2 and DY) mammographic parenchymal pattern and 200 controls with low-risk (N1 and P1) patterns in order to investigate the effect of food and nutrient intake on mammographic patterns. Mammograms were evaluated according to the Wolfe classification system. Dietary data were obtained from 7-day food diaries. Mean daily intake of nutrients was computed from standard UK food tables. The adjusted odds ratio (OR) of having a high-risk pattern in women in the highest tertile of total protein and carbohydrate intake was twice that of women in the lowest tertile (OR = 2.00; 95% confidence interval (CI) 1.06-3.77; P = 0.04 and OR = 1.93; 95% CI 1.03-3.59; P = 0.04 respectively). There was no excess risk for fat intake. In addition, there was no association between intake of vitamins and mammographic parenchymal patterns. Total meat intake was strongly and positively associated with high-risk patterns among post-menopausal women (OR = 2.50, 95% CI 1.09-5.69, P = 0.03). Our study suggests that certain macronutrients and foods such as protein, carbohydrate and meat intake influence the risk of breast cancer through their effects on breast tissue morphology, whereas fat and vitamins do not affect mammographic density. It seems that parenchymal pattern acts as an informative biomarker of the effect of some macronutrient and foodstuffs intake on breast cancer risk.

Adipose Tissue↗
PubMed1999

Pattern analysis for ultrasound anomalies in fetuses with normal karyotype.

Two hundred cases of double or multiple anomalies (up to five in the same fetus) out of 828 karyotypically normal fetuses with at least one ultrasound finding were enrolled in the present study. One hundred and sixty patterns belonging to 200 fetuses were found. Then, we included in the final analysis only those double or triple patterns of anomalies with frequency more then 1. Thus, 123 cases and 83 patterns were analyzed. A double pattern was intended as any combination of ultrasound findings present in the same fetus. Exact Chi-square test was used to evaluate the specificity of the association of the most frequent patterns. The association of patterns was expressed as ratio between observed and expected frequency (O/E) ratio. Pattern analysis was used as statistical tool to calculate the number of possible associations of ultrasound finding. Anomalies of fluid distribution, as well as Central Nervous System malformations, and facial malformations were among the most significant associations. Among the triple patterns, Cleft Lip + Cleft Palate + Holoprosencephaly showed the highest degree of association. Antenatal diagnosis of ultrasound finding can benefits by considering the present results.

Abnormalities, Multiple↗