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PubMed2006

Partial remission. A common outcome in older adults treated for major depression.

Major depression can affect up to 10% of older adults in clinical samples. Longitudinal studies of older adults with major depression report that a significant proportion of patients do not fully recover. Partial remission or symptoms of major depression that do not meet criteria for major depression, is predicted by 1) clinical factors, such higher number of symptoms at diagnosis, presence of comorbid dysthymia, and health problems; 2) social variables, such as high levels of perceived stress and low levels of perceived social support; and 3) perceived health/well-being variables, such as limitations in mobility or instrumental activities of daily living, poorer self-perceived health, finding life not satisfying, and looking back over life and finding it unhappy. Treatment options include antidepressants (alone or in combination) and psychotherapy.

Aged↗
PubMed2006

Screening of foetal distress by assessment of umbilical cord lactate.

PURPOSE OF INVESTIGATION: Studies on umbilical cord blood for determination of lactate indicate that high levels seem to be correlated to foetal metabolism for anaerobic glycolysis taking place in oxygen-deprived tissues of the foetus. These findings may be of particular-deprived clinical importance when foetal distress or foetal hypoxemia is caused by perinatal events. METHODS: The maternal and foetal heart rates, acid-base values measured and the outcome of 94 pregnancies complicated by intrapartum foetal asphyxia have been reviewed, and the maternal and foetal acid-base and lactate levels during the course of labour and at delivery were studied in patients with evidence of metabolic acidosis. Lactate concentrations were measured during labour and at delivery in blood samples obtained from the foetal presenting part and from the umbilical cord with the use of a rapid electrochemical technique. The foetuses were evaluated by means of the Apgar score, intrapartum cardiotocography, observation of the presence of meconium stained amniotic fluid, and clinical features of distress at birth. RESULTS: Evidence of clinical foetal distress was not related to the severity of the asphyxia. An increased lactate level was found in asphyctic infants and a clear correlation between lactic acidosis and foetal distress was documented. Low Apgar scores were observed in infants with moderate or severe asphyxia at delivery. Scalp lactate correlated significantly with umbilical artery lactate, but not with 1-min or 5-min Apgar scores. The lactate concentration was higher in cases of instrumental delivery compared to spontaneous delivery. No perfect correlation was found between lactate level and neonatal outcome but there were not a significant number of neonates with immediate complications. The rate of forceps delivery in the distress group was significantly higher than that of the healthy foetuses, so spontaneous labour was less frequently associated with foetal distress than instrumental delivery. In the distress group, severe variable decelerations were generally recorded in the second stage of labour. The incidence of neonatal Apgar score < or = 7 in neonates with abnormal baseline foetal heart rate (FHR) was higher than in those with severe variable decelerations, mild variable decelerations, and transient tachycardia. Duration of the active second stage of labour was significantly with the presence of foetal lactate at the time of crowning of the foetal head and the presence of lactate in umbilical arterial and vein blood at delivery. Expulsion time > or = 45 minutes, compared with shorter active second stage, and acidaemia at birth implied larger arterial-venous lactate differences. The presence of foetal lactate at crowning was also significantly associated with the level of umbilical arterial-venous lactate difference. CONCLUSION: Lactate and pH values provide the best parameters to distinguish between asphyctic and normal newborns, with lactate having the most discriminating power. The prospective value of the discrimination functions derived from lactate and pH data is good when the foetuses are allocated into normal parameters but poor when an attempt is made to allocate the foetuses into pathologic ones, with a high false-negative rate. However, the discriminating ability is improved when pathologic foetuses are included into one single abnormal group. These results confirm the potential use of rapid foetal blood lactate measurements for the early diagnosis of intrapartum foetal distress.

Acidosis, Lactic↗
PubMedDate not supplied

Designing self-report instruments for family assessment.

As family medicine research expands, more and better self-report measures for quantifying family systems variables will be required. These measures should be developed from an accepted paradigm for instrument design that includes the following. They should be: 1) grounded in a contemporary conceptual framework; 2) constructed following a rational theoretical design that includes the sequential stages of construct identification, construct definition, item generation, item editing, item formatting, and item scoring; 3) analyzed empirically at the item level for item distribution characteristics, item-scale correlation, and item-response style correlations; 4) analyzed at the scale level for scale distribution characteristics, scale-scale correlations, and scale-response style correlation; 5) revised based on editing and empirical analysis; and 6) psychometrically evaluated for reliability (eg, internal consistency, test-retest) and validity (construct related, criterion related, and content related). Normative data from various reference populations must also be obtained to provide a basis for interpreting scores. Finally, test manuals must be written to summarize test development data and provide information on administration procedures, scoring, and interpretation.

Behavior↗
PubMedDate not supplied

Profile of the well-controlled, well-adjusted hypertensive patient.

The study purpose was to identify discriminant predictors of blood pressure control and adjustment to chronic illness in 450 hypertensive patients. Hypertension control was determined by physician judgment, and adjustment was assessed by Derogatis' (1977) Psychosocial Adjustment to Illness Scale. Potential predictors of the outcome variables were measured by structured interview, formal instruments, and chart review. Well-controlled hypertensive patients had better health adjustment scores, reported more illness-related job problems and less illness-related sexual problems, were more satisfied with health care, knew what to do about medication side effects, were on medications longer, and had lower blood pressure readings on chart review. Well-adjusted hypertensive patients had fewer hypertension-related problems; had their blood pressure under control; were less likely to eat, smoke, or use drugs to handle tension; had no recent weight gain; knew what to do about medication side effects and that there is no cure for hypertension; were less pessimistic and less likely to worry; rated their stress level lower and their quality of life higher; felt that their health was under their own control; tried to problem solve when coping with stress; were on hypertensive medications a shorter time and on fewer medications overall; did not like to be alone when feeling stressed; and ate fewer high sodium foods.

Adaptation, Psychological↗
PubMedDate not supplied

The relation of selected psychosocial variables to single status of adult women during pregnancy.

This study examined levels of life stress, social support, anxiety, depression, and self-esteem in a convenience sample of 141 adult prenatal clinic patients during the midtrimester of normal pregnancies. Subjects identified themselves as "partnered" (either legally married or living with a stable partner, n = 116) or "single" (without a spouse or partner, n = 25). Groups were comparable on all demographic and obstetric variables. All subjects were tested with standardized instruments during routine clinic visits. Using t tests for independent groups, analyses showed single women to be higher in life stress (p = .03), lower in tangible support (p = .007), and higher in state anxiety (p = .01). Single women did not differ significantly on levels of informational and emotional support, trait anxiety, depression, or self-esteem. The differences between groups suggest that pregnancy may be a significant situational crisis associated with increased anxiety for single women.

Adult↗
PubMed1983

Heart rate variability, cardiac mechanics, and subjectively evaluated stress during simulator flight.

The effects of a simulator flight task on the heart rate variation (HRV) and hemodynamic variables were studied in nine pilots with instrument flight ratings. An electrocardiogram (ECG), phonocardiogram (PCG), and impedance cardiogram (ICG) were recorded continuously during three successive flights. Indices of HRV, power spectra, and autocorrelograms were computed from the R-R interval signal. Stroke volume (SV), cardiac output (CO), and systolic time intervals (STI) were determined by means of the ECG, PCG, and ICG. A scaling method for a subjective evaluation of tiredness, effort, and success during the flight was used. The repeats of the flight task decreased the heart rate (HR), CO, and cardiac index (CI). The different phases of the flight altered the HR (mean 97 min-1, S.E.M. 4 min-1), total HRV (RMSM) (mean 33 ms, S.E.M. 5 ms), and the periodic HRV. Subjectively, the pilots felt only moderate stress. The subjectively evaluated tiredness was significantly associated with the STI. Moderate informative stress in the flight simulator affected the chronotropic parameters of the heart. The inotropic state of the heart was not affected by the different phases of the flight but possibly by the diminishing sympathetic drive with accommodation during the repeats.

Adult↗
PubMed1994

Midcarpal arthroscopy: anatomy and portals.

Arthroscopy of the midcarpal joint of the wrist is a relatively new procedure made possible by the advances and miniaturization of arthroscopic instrumentation. Only recently has even the basic variability in the normal anatomy of the midcarpal joint been delineated. Midcarpal arthroscopy is becoming a routine part of a complete diagnostic wrist arthroscopy and is offering good views of midcarpal anatomy and new opportunities for arthroscopic treatment of midcarpal and proximal wrist joint traumatic and degenerative pathology.

Arthroscopy↗
PubMed2004

Cooling detection thresholds in the assessment of diabetic sensory polyneuropathy: comparison of CASE IV and Medoc instruments.

OBJECTIVE: Cooling detection threshold testing may be an important quantitative method for assessing polyneuropathy, in that it has traditionally been viewed as a measure of small-fiber involvement. The present study sought to determine the agreement between two common testing devices and to determine whether these are concordant in their association with predictor variables for diabetic sensory polyneuropathy. RESEARCH DESIGN AND METHODS: A total of 83 patients with diabetes (10 patients with type 1 diabetes and 73 patients with type 2 diabetes) and a wide spectrum of diabetic sensory polyneuropathy severity underwent concurrent cooling detection threshold testing using the Medoc and CASE IV instruments. Common predictor variables for diabetic sensory polyneuropathy were measured on the same day. RESULTS: Measurements of cooling detection thresholds by both instruments were highly correlated (Spearman's correlation coefficient 0.81, P < 0.001) and demonstrated a high degree of agreement by the method of Bland and Altman (95% distribution critical values for the difference in cooling detection thresholds, +7.5 and -5.6 degrees C). Cooling detection thresholds by both instruments were strongly correlated with clinical indicators of large-fiber neuropathy but not with the symptoms of small-fiber neuropathy (pain). CONCLUSIONS: These two instruments available for assessment of cooling detection thresholds are interchangeable for research in diabetic sensory polyneuropathy. However, this modality is equivalent to other modalities of quantitative sensory threshold testing in its association with indicators of large-fiber neuropathy and does not seem to provide an advantage for the prediction of small-fiber involvement.

Diabetic Neuropathies↗
PubMed2005

Closed-loop, multiobjective optimization of analytical instrumentation: gas chromatography/time-of-flight mass spectrometry of the metabolomes of human serum and of yeast fermentations.

The number of instrumental parameters controlling modern analytical apparatus can be substantial, and varying them systematically to optimize a particular chromatographic separation, for example, is out of the question because of the astronomical number of combinations that are possible (i.e., the "search space" is very large). However, heuristic methods, such as those based on evolutionary computing, can be used to explore such search spaces efficiently. We here describe the implementation of an entirely automated (closed-loop) strategy for doing this and apply it to the optimization of gas chromatographic separations of the metabolomes of human serum and of yeast fermentation broths. Without human intervention, the Robot Chromatographer system (i) initializes the settings on the instrument, (ii) controls the analytical run, (iii) extracts the variables defining the analytical performance (specifically the number of peaks, signal/noise ratio, and run time), (iv) chooses (via the PESA-II multiobjective genetic algorithm), and (v) programs the next series of instrumental settings, the whole continuing in an iterative cycle until suitable sets of optimal conditions have been established. Genetic programming was used to remove noise peaks and to establish the basis for the improvements observed. The system showed that the number of peaks observable depended enormously on the conditions used and served to increase them by as much as 3-fold (e.g., to over 950 in human serum) while in many cases maintaining or reducing the run time and preserving excellent signal/noise ratios. The evolutionary closed-loop machine learning strategy we describe is generic to any type of analytical optimization.

Fermentation↗
PubMed2002

Predicting follow-up living setting in patients with stroke.

OBJECTIVE: To examine living setting at 3- to 6-month follow-up for inpatients with functional impairments discharged from medical rehabilitation. DESIGN: Retrospective performed by using information from the Uniform Data System for Medical Rehabilitation (UDSMR) representing medical rehabilitation patients across the United States. SETTING: National survey data. PARTICIPANTS: Information submitted in 1997 and 1998 to the UDSMR by 167 facilities from 40 states was examined. A total of 9587 patient records were included in the final sample. The mean age +/- standard deviation was 70.2+/-12.4 years. The sample included 51.6% women and was comprised of 77.5% non-Hispanic white patients, with an average length of stay of 22.3+/-4.6 days. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Living setting (home vs not at home) at 3- to 6-month follow-up. RESULTS: A discriminant function training model including 8 statistically significant variables correctly classified 85.1% of the patients (n=8149). The total FIM instrument score, patient age, function-related group, and marital status were found to be useful classification variables. Wilks lambda for the model was.924 (chi(2)=1031.49, P<.000). The area under the receiver operating characteristics curve was.85. CONCLUSION: The association among functional abilities, demographic characteristics, and follow-up living setting in patients with stroke is complex. Functional variables can be used to help predict follow-up living setting. These variables change based on patient severity level.

Activities of Daily Living↗
PubMed1994

Behavioral states in the fetal baboon.

This study was designed to characterize behavioral states in the fetal baboon. Automated methods were developed and validated to recognize behavioral states based on relationships among three physiologic variables (EEG patterns, eye movements, heart period variability). Data included twelve 16-h records from 3 chronically instrumented fetal baboons at 0.8-0.9 of term. Randomly generated control records were used to differentiate occurrences of state from chance association of the variables. For 41.2 +/- 4.6% (mean +/- S.E.) of the time, the physiologic variables were synchronous and formed cycles of state with a mean duration of 34.4 min. Components of these cycles had mean +/- S.E. durations of 7.2 +/- 0.3 min for state 1FB (the analogue of quiet sleep in the human infant and state 1F in the human fetus), 20.7 +/- 1.2 min for the state 2FB (the analogue of active sleep in the human infant and state 2F in the human fetus), and 3.6 +/- 0.2 min for state transitions. For 24.6 +/- 2.4% of the time, the state variables exhibited coincidental, state-like agreements, that were not part of state cycles. Finally, for 34.3 +/- 2.7% of the time, there was no systematic agreement among the three variables. These data provide convincing evidence that organized behavioral states are present in the fetal baboon as early as 0.8 of term gestation.

Algorithms↗
PubMed1997

Cyclic fatigue testing of nickel-titanium endodontic instruments.

Cyclic fatigue of nickel-titanium, engine-driven instruments was studied by determining the effect of canal curvature and operating speed on the breakage of Lightspeed instruments. A new method of canal curvature evaluation that addressed both angle and abruptness of curvature was introduced. Canal curvature was simulated by constructing six curved stainless-steel guide tubes with angles of curvature of 30, 45, or 60 degrees, and radii of curvature of 2 or 5 mm. Size #30 and #40 Light-speed instruments were placed through the guide tubes and the heads secured in the collet of a Mangtrol Dynamometer. A simulated operating load of 10 g-cm was applied. Instruments were able to rotate freely in the test apparatus at speeds of 750, 1300, or 2000 rpm until separation occurred. Cycles to failure were determined. Cycles to failure were not affected by rpm. Instruments did not separate at the head, but rather at the point of maximum flexure of the shaft, corresponding to the midpoint of curvature within the guide tube. The instruments with larger diameter shafts, #40, failed after significantly fewer cycles than did #30 instruments under identical test conditions. Multivariable analysis of variance indicated that cycles to failure significantly decreased as the radius of curvature decreased from 5 mm to 2 mm and as the angle of curvature increased greater than 30 degrees (p < 0.05, power = 0.9). Scanning electron microscopic evaluation revealed ductile fracture as the fatigue failure mode. These results indicate that, for nickel-titanium, engine-driven rotary instruments, the radius of curvature, angle of curvature, and instrument size are more important than operating speed for predicting separation. This study supports engineering concepts of cyclic fatigue failure and suggests that standardized fatigue tests of nickel-titanium rotary instruments should include dynamic operation in a flexed state. The results also suggest that the effect of the radius of curvature as an independent variable should be considered when evaluating studies of root canal instrumentation.

American Dental Association↗
PubMed2003

Clinical considerations and rationale for the use of simplified instrumentation in occlusal rehabilitation. Part 1: Mounting of the models on the articulator.

The development of an occlusal scheme with an appropriate number and location of occlusal contacts is of the utmost importance for the long-term success of any prosthetic rehabilitation. This, however, can be a time-consuming procedure. To avoid undue mistakes, a high degree of competence must be demonstrated by both the clinician and the technician. Especially when performing extensive rehabilitations, many operators believe that to have optimum control of the occlusal variables, it is necessary to employ rather sophisticated instruments and complicated procedures. This article presents a rationale for an approach that uses a simplified but sound instrumentation in the clinical and laboratory steps necessary to produce a successful prosthesis. In part 1, the registration of the spatial position of a patient's maxillary and mandibular arches is described.

Centric Relation↗
PubMed2003

Development of a spanish-language version of the U.S. household food security survey module.

A survey module used to monitor the prevalence of household food insecurity and hunger in the United States was developed by a broadly based collaborative project with leadership from the USDA and the National Center for Health Statistics (NCHS). It has been administered annually since 1995 as a supplement to the Census Bureau's Current Population Survey (CPS) and is part of the National Health and Nutrition Examination Survey (NHANES) and other national surveys. Spanish is the second most common language in the United States, yet no standardized Spanish-language version of this instrument has yet been sanctioned by the relevant federal agencies. In the CPS, interviewers free-translate the questions while interviewing respondents who prefer to have the interview conducted in Spanish. National prevalence data indicate relatively high rates of food insecurity for Hispanic households, raising the question whether methodological artifacts may contribute to these rates. We analyzed eight Spanish-language versions of the instrument that have been used in published work for variability in wording and phrasing. We then conducted focus groups of low-income Spanish-speaking participants from Mexico, Central America, Puerto Rico and Cuba to refine a single Spanish-language instrument. We also employed professional translators to render the English instrument into "standard" Spanish; both instruments were then back-translated. The focus group-derived instrument uses simpler language and grammar; its back-translation integrity to the English version was slightly better than the professionally translated version. We provide the instrument for use and further testing by other investigators.

Food Supply↗
PubMed1998

Prenatal coke: what's behind the smoke? Prenatal cocaine/alcohol exposure and school-age outcomes: the SCHOO-BE experience.

Despite media reports and educators' concerns, little substantive data have been published to document or refute the emerging reports that children prenatally exposed to cocaine have serious behavioral problems in school. Recent pilot data from this institution have indeed demonstrated teacher-reported problem behaviors following prenatal cocaine exposure after controlling for the effects of prenatal alcohol use and cigarette exposure. Imperative in the study of prenatal exposure and child outcome is an acknowledgement of the influence of other control factors such as postnatal environment, secondary exposures, and parenting issues. We report preliminary evaluation from a large ongoing historical prospective study of prenatal cocaine exposure on school-age outcomes. The primary aim of this NIDA-funded study is to determine if a relationship exists between prenatal cocaine/alcohol exposures and school behavior and, if so, to determine if the relationship is characterized by a dose-response relationship. A secondary aim evaluates the relationship between prenatal cocaine/alcohol exposures and school achievement. Both relationships will be assessed in a black, urban sample of first grade students using multivariate statistical techniques for confounding as well as mediating and moderating prenatal and postnatal variables. A third aim is to evaluate the relationship between a general standardized classroom behavioral measure and a tool designed to tap the effects thought to be specific to prenatal cocaine exposure. This interdisciplinary research team can address these aims because of the existence of a unique, prospectively collected perinatal Database, funded in part by NIAAA and NICHD. The database includes repeated measures of cocaine, alcohol, and other substances for over 3,500 births since 1986. Information from this database is combined with information from the database of one of the largest public school systems in the nation. The final sample will be composed of over 600 first grade students for whom the independent variables, prenatal cocaine/alcohol exposures, were prospectively assessed and quantified at the university maternity center. After informed consent, the primary dependent variable, school behavior, is assessed, using the PROBS-14 (a teacher consensus developed instrument), the Child Behavior Check List, and the Conners' Teacher Rating Scale. The secondary dependent measure, school achievement, is measured by the Metropolitan Achievement Text and the Test of Early Reading Ability. Control variables, such as the environment and parenting, are measured by several instruments aimed at capturing the child and family ecology since birth. All analyses will be adjusted as appropriate for prospectively gathered control variables such as perinatal risk, neonatal risk, and other prenatal drug and cigarette exposures. Further adjustment will be made for postnatal social risk factors which may influence outcome. Of particular concern are characteristics of the home (adaptation of HOME), parent (depression, stress), and neighborhood (violence exposure). Finally, postnatal exposure to lead and other drugs is being considered.

Achievement↗
PubMed2002

Climate change in the North Pacific region over the past three centuries.

The relatively short length of most instrumental climate records restricts the study of climate variability, and it is therefore essential to extend the record into the past with the help of proxy data. Only since the late 1940s have atmospheric data been available that are sufficient in quality and spatial resolution to identify the dominant patterns of climate variability, such as the Pacific North America pattern and the Pacific Decadal Oscillation. Here we present a 301-year snow accumulation record from an ice core at a height of 5,340 m above sea level-from Mount Logan, in northwestern North America. This record shows features that are closely linked with the Pacific North America pattern for the period of instrumental data availability. Our record extends back in time to cover the period from the closing stages of the Little Ice Age to the warmest decade in the past millennium. We find a positive, accelerating trend in snow accumulation after the middle of the nineteenth century. This trend is paralleled by a warming over northwestern North America which has been associated with secular changes in both the Pacific North America pattern and the Pacific Decadal Oscillation.

Journal Article↗
PubMed1987

Reliability of two-point discrimination measurements.

Both moving and static two-point discrimination are valid measurements of functional sensibility in the hand. The present study investigated the interobserver variability of these measurements when two observers used the same testing instrument and the same definition of the testing procedure's end point. In testing 30 nerve-injured patients, interobserver variability was found to vary within 1 mm, or less, for moving two-point discrimination in 93.3% of the measurements and for static two-point discrimination in 86.8% of the measurements. In only two of the 30 measurements of moving two-point discrimination and in four of the measurements for static two-point discrimination were interobserver differences equal to 2 mm. Measurements for both moving and static two-point discrimination were analyzed statistically by linear regression and correlation co-efficient techniques. The measurements for two-point discrimination obtained with the protocol employed in this study were found to have an interobserver reliability at the p less than 0.00001 level.

Hand↗
PubMed2004

Determining sociability, social space, and social presence in (a)synchronous collaborative groups.

The effectiveness of group learning in asynchronous distributed learning groups depends on the social interaction that takes place. This social interaction affects both cognitive and socioemotional processes that take place during learning, group forming, establishment of group structures, and group dynamics. Though now known to be important, this aspect is often ignored, denied or forgotten by educators and researchers who tend to concentrate on cognitive processes and on-task contexts. This "one-sided" educational focus largely determines the set of requirements in the design of computer-supported collaborative learning (CSCL) environments resulting in functional CSCL environments. In contrast, our research is aimed at the design and implementation of sociable CSCL environments which may increase the likelihood that a sound social space will emerge. We use a theoretical framework that is based upon an ecological approach to social interaction, centering on the concept of social affordances, the concept of the sociability of CSCL environments, and social presence theory. The hypothesis is that the higher the sociability, the more likely that social interaction will take place or will increase, and the more likely that this will result in an emerging sound social space. In the present research, the variables of interest are sociability, social space, and social presence. This study deals with the construction and validation of three instruments to determine sociability, social space, and social presence in (a)synchronous collaborating groups. The findings suggest that the instruments have potential to be useful as measures for the respective variables. However, it must be realized that these measures are "first steps."

Adult↗