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PubMedDate not supplied

Maternal correlates of growth in toddler vocabulary production in low-income families.

This study investigated predictors of growth in toddlers' vocabulary production between the ages of 1 and 3 years by analyzing mother-child communication in 108 low-income families. Individual growth modeling was used to describe patterns of growth in children's observed vocabulary production and predictors of initial status and between-person change. Results indicate large variation in growth across children. Observed variation was positively related to diversity of maternal lexical input and maternal language and literacy skills, and negatively related to maternal depression. Maternal talkativeness was not related to growth in children's vocabulary production in this sample. Implications of the examination of longitudinal data from this relatively large sample of low-income families are discussed.

Child, Preschool↗

PubMed1995

In-patient care for symptomatic, HIV-infected persons: a longitudinal study of hospitalizations, in-patient drug use, and related costs.

Patterns in the costs of hospital in-patient care and in-patient drug treatment of 121 symptomatic, HIV-infected patients are described for a university hospital between 1987 and 1991. Trend analyses have been performed on quarterly and yearly data using parametric and non-parametric statistical techniques. During the 5-year study period the demand for hospital beds almost quadrupled despite a constant number of admissions per person-year and a 40% decrease in the average length of stay. The demand for beds was highest in the autumn and winter months. The impact of female and/or heterosexual subgroups on the yearly utilization of resources increased and reasons for hospitalization became more diverse; there were fewer hospitalizations for Pneumocystis carinii pneumonia infection. Antimicrobial drug treatment accounted for the increased drug treatment costs. The implications for AIDS-treating specialists, hospital managers, and scenario analysts are discussed.

AIDS-Related Opportunistic Infections↗

PubMed1993

Intracellular injection of neurobiotin or horseradish peroxidase reveals separate types of preganglionic neurons in the sacral parasympathetic nucleus of the cat.

Sacral preganglionic neurons are essential to the neural control of the excretory and sex organs. Previously employed multi-cell tracing methods have certain limitations in the precise morphological analysis of the neural pathways that control these organs. These limitations were overcome by the intracellular injection of neurobiotin or horseradish peroxidase into single preganglionic neurons in the lateral sacral parasympathetic nucleus of the cat. Following light microscopic examination, these neurons, as a group, were found to have an average of five stem dendrites, which divided into 15 dendritic end-branches that were distributed among eight dendritic terminal fields. These dendrites had a major transverse orientation and were quite long, many of them reaching well into the dorsal and ventral horns and into the dorsal gray commissure. These dendrites also exhibited a major longitudinal orientation, extending an average of 869 microns (combined length of rostral and caudal dendrites) within the nucleus. Two groups of cells emerged on the basis of different dendritic patterns. Cells classed as Type I had dendrites in lamina I and in the ventral horn but lacked a significant projection into the lateral funiculus. Cells classed as Type II had major dendritic projections into the lateral funiculus but lacked dendrites in lamina I. The diverse dendritic patterns of these two cell types indicate dissimilar afferent control mechanisms and suggest that these preganglionic neurons may innervate different target organs.

Animals↗

PubMed1998

Sonic/vocal motor pathways in catfishes: comparisons with other teleosts.

Among teleost fishes, representatives of several distantly related groups have sound-producing (sonic/vocal) muscles associated with the swimbladder or pectoral girdle/fin. Here, the diversity of vocal organs and central motor pathways in four families of catfish, order Siluriformes, is compared to that in families from two distantly related orders, the Scorpaeniformes and Batrachoidiformes. Several catfish families have two sonic mechanisms--a swimbladder vibration established by 'drumming muscles' that differ in origin and insertion between families, and a pectoral spine stridulatory apparatus. In ariids, mochokids and doradids, sonic swimbladder muscles originate at various cranial or postcranial elements and insert onto an 'elastic spring' that vibrates the swimbladder, while in pimelodids the muscles insert ventrally at the swimbladder. Sonic motoneurons are located along the midline, ventral to the fourth ventricle/central canal in doradids and mochokids but lateral to the medial longitudinal fasciculus in ariids; pimelodids have motoneurons in both locations. The axonal trajectory for the lateral motoneurons in pimelodids and ariids implies that they are a migrated, midline population of sonic motoneurons. Pectoral spine-associated motoneurons are located in the ventral motor column. Unlike catfishes, a diversity of sonic mechanisms in Scorpaeniformes is not associated with different positions for sonic motoneurons. Cottids (sculpin) lack a swimbladder but have sonic muscles that originate at the occipital cranium and insert at the pectoral girdle; sonic motoneurons are located within the ventral motor column. Some triglids have intrinsic swimbladder muscles, although ontogenetic data indicate a transient association with the pectoral girdle; sonic motoneurons are in the same location as in cottids. Among Batrachoidiformes, all known representatives have intrinsic swimbladder muscles that are never associated with the pectoral girdle and are innervated by midline sonic motoneurons. The results suggest two patterns of organization for sound-producing systems in teleost fishes: pectoral fin/girdle-associated muscles are innervated by sonic motoneurons positioned within the ventral motor column, adjacent to the ventral fasciculus; non-pectoral associated muscles are innervated by sonic motoneurons located on or close to the midline, adjacent to the medial longitudinal fasciculus.

Air Sacs↗

PubMedDate not supplied

Nursing doctoral program evaluation: Alumni outcomes.

Meaningful examination of program outcomes is one of the most challenging tasks facing faculty and administrators involved in the design and delivery of educational programs. This article reports the outcomes for one doctoral program in nursing and elucidates salient conceptual and methodologic issues in educational outcomes research for this discipline. Career development, scholarly productivity, and professional leadership were the foci of this outcomes study. Three instruments were used; data were provided by alumni, graduate faculty, and alumni supervisors. Data analysis techniques included content analysis and descriptive and correlational statistics. Results showed that graduates embarked on diverse career paths with the majority employed in academic institutions. Most graduates reported active involvement in research, publications, presentations, and professional leadership. Employment pattern differences were noted between academic year and summer-only program graduates with associated divergence in career emphasis, research productivity, and job satisfaction. A positive correlation of time since degree conferral with scholarly productivity and professional leadership was noted. Recommendations for future research include refining outcomes, linking process to outcome, using longitudinal designs, and attending to unique nursing student and doctoral program characteristics.

Achievement↗

PubMed1994

A longitudinal survey of Borrelia crocidurae prevalence in rodents and insectivores in Senegal.

We report results of a longitudinal survey designed to determine the importance and the dynamics of Borrelia crocidurae, the spirochete responsible for tick-borne relapsing fever in West Africa in rodents and insectivores in a rural area of northern Senegal. A total of 954 animals were caught during bimonthly capture sessions over a two-year period. Positive thick blood smears were recorded in 17.6% of the 740 rodents and 7.3% of the 55 musk shrews tested. Variations of prevalence were analyzed in Arvicanthis niloticus and Mastomys huberti, which represented 62.7% and 28.3%, respectively. of the animals captured, and 65.7% and 27.6%, respectively, of the animals found infected. Borrelia crocidurae prevalence was significantly different between captures and fluctuated separately for each species. Age-specific prevalence of B. crocidurae showed distinct patterns, decreasing with age from 50% in younger juveniles to 3% in older adults for A. niloticus, while increasing with age from 8% to 23% for M. huberti. No relationship was observed with animal abundance or with the season of the year for either species. These findings suggest that the diversity of the population dynamics of host-vector-parasite associations in the Sahel region of Senegal may be a key factor for the relative stability of the borreliosis reservoir.

Age Factors↗

PubMed1981

Alcohol and high-density lipoprotein cholesterol: causal inference from diverse study designs.

The association between reported alcohol intake and plasma high-density lipoprotein (HDL) cholesterol concentration is examined in an effort to establish whether it was a cause-and-effect basis. A cross-sectional descriptive study of several populations reveals a strong and consistent dose-response pattern: Social drinkers have mean HDL cholesterol levels that are higher than those of teetotalers by as much as 33%. Cross-sectional analyses in another epidemiological study reveal the association to be independent of potential confounding factors such as smoking and body weight, and longitudinal analyses suggest that it is also not a result of certain unmeasured sources of confounding. A small experiment reveals a 15% reduction in HDL cholesterol levels among social drinkers who abstain from alcohol from a 2-week period. The evidence supports the conclusion that alcohol habits are probably one of the determinants of plasma HDL cholesterol level. A clarification of the relevance of this phenomenon to clinical medicine awaits future clinical efforts.

Alcohol Drinking↗

PubMed2003

Acoustic response properties of lagenar nerve fibers in the sleeper goby, Dormitator latifrons.

Auditory and vestibular functions of otolithic organs vary among vertebrate taxa. The saccule has been considered a major hearing organ in many fishes. However, little is known about the auditory role of the lagena in fishes. In this study we analyzed directional and frequency responses from single lagenar fibers of Dormitator latifrons to linear accelerations that simulate underwater acoustic particle motion. Characteristic frequencies of the lagenar fibers fell into two groups: </=50 Hz and 80-125 Hz. We observed various temporal response patterns: strong phase-locking, double phase-locking, phase-locked bursting, and non-phase-locked bursting. Some bursting responses have not been previously observed in vertebrate otolithic nerve fibers. Lagenar fibers could respond to accelerations as small as 1.1 mm s(-2). Like saccular fibers, lagenar fibers were directionally responsive and decreased directional selectivity with stimulus level. Best response axes of the lagenar fibers clustered around the lagenar longitudinal axis in the horizontal plane, but distributed in a diversity of axes in the mid-sagittal plane, which generally reflect morphological polarizations of hair cells in the lagena. We conclude that the lagena of D. latifrons plays a role in sound localization in elevation, particularly at high stimulus intensities where responses of most saccular fibers are saturated.

Acoustic Stimulation↗

PubMedDate not supplied

Adolescent social competence: effectiveness in a group setting.

We used a longitudinal data set to evaluate an observational assessment of adolescent competence within a group context. Participants were 40 (21 males, 19 females) ethnically diverse children who had earlier been observed in summer camp (age 10) and preschool (age 4 1/2), as well as in infancy. A revealed differences task was videotaped as part of an intensive weekend camp reunion at ages 15 to 16. Raters, blind to the adolescents' developmental histories, coded each adolescent on the following behavioral rating scales: enjoyment of the task, involvement, leadership, self-confidence in the task, and global social competence. Both concurrent validity (strong correlations with independent camp reunion counselor ratings and peer sociometric measures) and clear associations with antecedent measures of peer competence in preschool and middle childhood were demonstrated. A pattern of correlations revealed considerable discriminate validity. Neither IQ nor socioeconomic status accounted for these associations. Overall, the results confirm the power of a developmentally appropriate, taxing, behaviorally based assessment of group functioning as a measure of competence in adolescence.

Adolescent↗

PubMed1992

Aged heterogeneity: fact or fiction? The fate of diversity in gerontological research.

Studies examining age-related changes typically report findings as age-based generalizations that neglect the phenomenon of variability in gerontological research. This paper examines the degree of attention given in 185 studies to individual differences and the empirical patterns of variability reported in those studies that present measures of dispersion. Measures of dispersion were reported in 43% of the gerontological studies reviewed and in 24% of the developmental studies. Overall, a majority of all gerontological studies presenting data reported increases in variability with increasing age (65%). This pattern was more pronounced in longitudinal studies than in cross-sectional ones.

Aging↗

PubMed2006

ZIP-code-based versus tract-based income measures as long-term risk-adjusted mortality predictors.

There is a well-established, strong association between socioeconomic position and mortality. Public health mortality analyses thus routinely consider the confounding effect of socioeconomic position when possible. Particularly in the absence of personally reported data, researchers often use area-based measures to estimate the effects of socioeconomic position. Data are limited regarding the relative merits of measures based on US Census tract versus ZIP code (postal code). ZIP-code measures have more within-unit variation but are also more easily obtained. The current study reports on 293,138 middle-aged men screened in 14 states in 1973-1975 for the Multiple Risk Factor Intervention Trial and having 25-year mortality follow-up. In risk-adjusted proportional hazards models containing either ZIP-code-based or tract-based median household income, all-cause mortality hazard ratios were 1.16 (95% confidence interval: 1.14, 1.17) per Dollars 10,000 less ZIP-code-based income and 1.15 (95% confidence interval: 1.13, 1.16) per Dollars 10,000 less tract-based income; adding either income variable to a risk-adjusted model improved model fit substantially. Both were significant independent predictors in a combined model; tract-based income was a slightly stronger mortality predictor (hazard ratios = 1.05 and 1.11 for ZIP-code-based and tract-based income, respectively). These patterns held across various causes of death, for both Blacks and non-Blacks, and with or without adjustment for ZIP-code-based income diversity or tract-based proportion below poverty.

Analysis of Variance↗

PubMed2002

Cognitive dysfunction in neuropsychiatric systemic lupus erythematosus.

Neuropsychiatric syndromes associated with systemic lupus erythematosus are common, but diverse in etiology and presentation. Cognitive dysfunction is prevalent among these syndromes, but exhibit a significant degree of heterogeneity both within and between patient variability. Earlier studies of SLE-associated cognitive dysfunction addressed its identification and description. Common associations were repeatedly acknowledged, including concomitant or past neuropsychiatric disease, use of corticosteroids, disease activity, emotional disturbance, and antiphospholipid antibodies. The past several years have focused more on elucidating the relative strengths of various risk associations, patterns of cognitive abnormalities, both cross-sectionally and longitudinally (, clinical course), and novel means to identify cognitive impairment, both functionally and biologically.

Cognition Disorders↗

PubMed2004

Temperature-related genetic changes in laboratory populations of Drosophila subobscura: evidence against simple climatic-based explanations for latitudinal clines.

Parallel latitudinal clines to the long-standing ones in the original Palearctic populations have independently evolved at different rates for chromosomal polymorphism and body size in South and North American populations of Drosophila subobscura since colonization around 25 years ago. This strongly suggests that (micro) evolutionary changes are largely predictable, but the underlying mechanisms are unknown. The putative role of temperature per se was investigated by using three sets of populations at each of three temperatures (13 degrees , 18 degrees , and 22 degrees C) spanning much of the tolerable range for this species. We found a lower chromosomal diversity at the warmest temperature; a quick and consistent shift in gene arrangement frequencies in response to temperature; an evolutionary decrease in wing size, mediated by both cell area and cell number, at 18 degrees C; no relationship between wing size and those inversions involved in latitudinal clines; and a shortening of the basal length of longitudinal vein IV relative to its total length with increasing standard dose. The trends for chromosomal polymorphism and body size were generally inconsistent from simple climatic-based explanations of worldwide latitudinal patterns. The findings are discussed in the light of available information on D. subobscura and results from earlier thermal selection experiments with various Drosophila species.

Animals↗

PubMed2000

Time-series analysis of the relationship between dizziness and stress.

Ten individuals with dizziness participated in a longitudinal study on the relationship between stress and dizziness. The participants rated dizziness and stress on visual analogue scales twice daily for a period of 28 days (in all 56 data points). The ratings of stress included physical stress, mental stress, emotional stress, and the presence of stressful events. The data was analysed by means of time-series analysis (ARIMA), and the temporal associations investigated by lagged correlations. Results showed concurrent associations between dizziness and mental and emotional stress. However, individual differences were observed indicating complex and diverse patterns of association between different forms of stress and dizziness.

Adult↗

PubMed2026

Delayed maturation of the milk microbiome in women with type 1 diabetes.

AIMS/HYPOTHESIS: The breastmilk microbiome plays a crucial role in gut microbial colonisation and immune development, but little is known about how it is influenced by type 1 diabetes. METHODS: We conducted a longitudinal 16S rRNA gene sequencing study of milk from women with type 1 diabetes (n=69 pregnancies; 174 samples) and women who did not have type 1 diabetes (n=49 pregnancies; 123 samples), collected at seven timepoints from birth to 15 months postpartum. Alpha diversity (richness, inverse Simpson evenness) was analysed by generalised linear mixed models, beta diversity was analysed by Bray-Curtis dissimilarities and PERMANOVA, and differential abundance was analysed by limma. Additionally, we examined associations with maternal genetic risk score (GRS), maternal HLA type, glycaemic management (HbA1c) and breastmilk secretory IgA (sIgA), and performed a parallel analysis for the infant stool microbiome. RESULTS: A significant interaction between type 1 diabetes status and timepoint was observed for alpha diversity, both richness (p=0.01) and inverse Simpson diversity (p=0.003), indicating distinct temporal trajectories between women with and without type 1 diabetes. In those without type 1 diabetes, richness increased significantly between birth and 1 week postpartum, but this early increase was delayed in women with type 1 diabetes to between 1 week and 3 months postpartum (p=0.002). Beta diversity analysis revealed earlier and more extensive compositional shifts in women without type 1 diabetes compared to those with type 1 diabetes. These differences persisted after adjusting for Caesarean delivery, BMI, parity and infant sex, and were not attributable to a delay in initiating breastfeeding. Taxa with delayed enrichment in women with type 1 diabetes included Streptococcus spp. and Rothia mucilaginosa, which metabolise human milk oligosaccharides to short-chain fatty acids to promote development of the infant's gut barrier and immune system. Maternal GRS, HLA, HbA1c or sIgA were not associated with milk microbiota diversity trajectories. In infant stool samples, alpha diversity did not differ between exposure groups, and showed no evidence of delayed maturation. Beta diversity revealed an early compositional shift between birth and 1 week postpartum only in infants born to women without type 1 diabetes. Similarly, significant taxonomic changes between birth and 1 week postpartum were detected only in infants born to women without type 1 diabetes, but with some taxa differing between exposure groups at 1 week. CONCLUSIONS/INTERPRETATION: Maternal type 1 diabetes is associated with delayed early maturation of the breastmilk microbiome. Early compositional differences in microbiota restructuring were also observed in the infant gut, partially mirroring the pattern in the milk microbiome; however, sustained differences in infant gut microbiota diversity were not detected. Further investigation could determine whether these changes affect development of the infant's gut and immune system.

Humans↗

PubMed1981

Catecholamine and cortisol excretion patterns in three-year-old children and their parents.

Urinary catecholamine and cortisol excretion was studied in a group of three-year-olds, their mothers and fathers during night rest, one day at home and one day at hospital. The stay in the hospital, which was part of a longitudinal study of the families, induced a pronounced rise in adrenaline excretion and a moderate increase in noradrenaline excretion in relation to the at-home level. Although the catecholamine excretion in relation to body weight was much higher in the children, the magnitude of the increase at the hospital was about the same in all the family members. The adrenaline excretion was also affected by the diverse conditions at the hospital and showed, for example, a marked decrease during lunch hour. The cortisol excretion at the hospital tended to be elevated only in fathers. On the average, mothers excreted about the same amount of adrenaline as the fathers at the hospital, but significantly more noradrenaline. In earlier studies males have shown a greater adrenaline output than females during achievement-demanding situations. The findings of this study were interpreted within the context of the specific challenge that the situation represented to the mothers. The mothers also excreted more noradrenaline in the at-home condition. Catecholamine and cortisol excretion levels within family members tended to be positively correlated, but the correlations were generally low.

Adult↗

PubMed2026

Five decades of pneumococcal meningitis in Spain: a single-centre, clinical and genomic, retrospective, observational study.

BACKGROUND: Pneumococcal meningitis remains a major threat, with high fatality rates and long-term sequelae, despite advances in vaccination and treatment. We aimed to examine the associations between pneumococcal serotypes, Global Pneumococcal Sequence Cluster (GPSC), antimicrobial resistance, source of infection, and clinical outcomes in adults with pneumococcal meningitis. METHODS: In this single-centre, clinical and genomic, retrospective, observational study, we analysed all laboratory-confirmed cases of adult pneumococcal meningitis recorded at Hospital Universitari de Bellvitge, Spain. Clinical data were obtained from a prospectively maintained clinical database and linked to microbiological and genomic data by unique patient identifiers. Clinical sources of infection were classified as cerebrospinal fluid leakage, acute otitis media, or haematogenous origin. Disease severity was defined as shock at presentation, sequelae as any persistent neurological deficit at discharge, and mortality as death within 30 days. Serotype data were available for 265 isolates, and whole-genome sequencing was done on 200 viable isolates. For outcome analyses, patients who did not receive dexamethasone were excluded. Serotype, GPSCs, antimicrobial susceptibility, phylogenetic, and genome-wide association study (GWAS) data were analysed to assess determinants of meningitis source, disease severity, sequelae, and 30-day mortality. FINDINGS: 387 adult patients (median age 58 years [IQR 45-68]; 54% male) with pneumococcal meningitis were recorded between Jan 1, 1974, and Dec 31, 2023. Acute otitis media was the most frequent source of pneumococcal meningitis (174 [45%] of 387 cases) and was mainly caused by serotype 3 (pneumococcal conjugate vaccine [PCV]13; GPSC12). The 30-day case-fatality rate in this group was 17 (10%) of 174 (95% CI 5·8-15·2). Haematogenous episodes accounted for 104 (27%) of 387 cases and had a significantly higher 30-day case-fatality rate (50 [48%] of 104; 95% CI 38·2-58·1; p<0·0001) with a higher frequency of serotype 4. Cerebrospinal fluid leakage accounted for 105 (27%) of 387 cases and had the lowest 30-day case-fatality rate (nine [9%] of 105; 95% CI 4·0-15·6) and broader serotype diversity. The introduction of PCV7 and PCV13 resulted in declines in vaccine-targeted serotypes and β-lactam resistance. Whole-genome sequencing identified 60 distinct GPSCs. Among prevalent lineages, GPSC16 (20 [10%] of 200; serotypes 19A and 23F) and GPSC6 (18 [9%] of 200; serotypes 9V, 11A, and 14) were associated with β-lactam resistance. GWAS did not identify genetic variants significantly associated with severity, sequelae, or mortality. INTERPRETATION: This longitudinal study provides a comprehensive view of adult pneumococcal meningitis over five decades, revealing changes in sources of infection, serotype distribution, pneumococcal lineages, and antimicrobial resistance patterns over time. Lineage-level findings suggested variability in clinical outcomes, underscoring the importance of continued genomic surveillance and supporting consideration of broader vaccine targets. GPSC12 predominance and its association with mortality and more severe outcomes highlight the need for preventive measures against serotype 3, although these findings require confirmation in larger multicentre cohorts. FUNDING: Instituto de Salud Carlos III, cofunded by European Social Fund, and the Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, and the Centro de Investigación Biomédica en Red de Enfermedades Infecciosas, both at the Instituto de Salud Carlos III.

Journal Article↗

PubMed2002

The selection and evolution of viral quasispecies in HIV-1 infected children.

OBJECTIVES: To analyse the diversity and divergence of the viral populations in three mother-child pairs in longitudinally obtained samples for up to 7 years. METHODS: Peripheral blood mononuclear cells were obtained from three mothers at delivery and three to four samples were obtained from each of their children from 1.5 months up to 78 months of age. The V3 region of HIV-1 was amplified by polymerase chain reaction, cloned and sequenced. HIV-1 DNA sequence comparisons were performed by phylogenetic analysis. RESULTS: The viral population was initially homogenous in two children but highly heterogeneous in one child. Three patterns of vertical transmission seemed to have occurred: transmission of the most prevalent maternal strain, of a minor maternal strain and of multiple maternal strains. In one child, a possible reappearance of a maternal sequence was observed at 34 months of age. CONCLUSIONS: Children may become infected with the most prevalent maternal strain, a minor maternal variant or multiple maternal quasispecies. Maternal viral variants may reappear in children after several years of infection and could possibly be derived from a reservoir of founder quasispecies established during the children's primary HIV-1 infection.

Adult↗