PubMed Health⌕ Search

Biomedical subjects

S Millar

Publications and source records attributed to S Millar.

At least 19 recordsLinked to original sources
PubMed1997

Cytokines in human breast milk.

In early life humans derive all their nutrients from milk. Human milk provides the neonate with not only a food source but also a source of biologically active molecules such as hormones, growth factors and cytokines. Cytokines are multifunctional glycoproteins involved in cell communication and immune system activation. Two of these cytokines, granulocyte-colony stimulating factor (G-CSF) and interleukin-6 (IL-6), are present in variable concentrations in human milk. We measured G-CSF and IL-6 concentrations in healthy nursing mothers. The 30 milk samples assayed contained G-CSF levels from 14 pg/mL to > 2500 pg/mL. Of the 28 milk samples assayed for IL-6, 24 contained levels from 0.81 pg/mL to 306 pg/ mL. The remainder had levels below the detection limit of the assay. These biologically active molecules may play a role in neonatal growth and development, and may also protect the infant against infection.

Granulocyte Colony-Stimulating Factor↗
PubMed1994

Human milk contains granulocyte colony stimulating factor.

Human milk provides the neonate with a variety of balanced nutrients and contains biologically active molecules such as hormones and growth factors. We have utilized a sensitive enzyme immunoassay to detect the granulocyte stimulator, granulocyte colony-stimulating factor (G-CSF) in human milk samples. The 12 milk samples tested contained G-CSF ranging from 45 to 1551 pg/ml.

Adult↗
PubMed1993

EGF abrogation-induced fusilli-form dysmorphogenesis of Meckel's cartilage during embryonic mouse mandibular morphogenesis in vitro.

Mutations associated with genes of the EGF superfamily are implicated in facial malformations arising from abnormal development of the first branchial arch. EGF and EGF receptor (EGFr) transcripts are expressed in the mouse embryonic first branchial arch and derivatives from E9 through E15. EGF transcripts are localized to ectomesenchymal cells associated with precartilage, cartilage, bone and tooth-forming cells. EGF and EGFr proteins co-localize to the same cells suggesting an autocrine regulation. To test whether EGF effects the timing and positional information required for Meckel's cartilage (MC) and tooth development, we cultured E10 mandibular explants in serumless, chemically defined medium with either antisense or sense EGF oligodeoxynucleotides. Antisense inhibition of EGF expression produces bilaterally symmetrical Fusilli-form dysmorphogenesis of MC and decreases tooth bud size; these effects are reversed by the addition of exogenous EGF to the culture medium. Tyrphostin RG 50864, which inhibits EGF receptor kinase activity, inhibits EGF stimulation of tyrosine phosphorylation in a concentration-dependent manner and severely retards mandibular development yet increases tooth size. These findings support the hypothesis that endogenous EGF and EGF-like proteins provide signalling to regulate the size and shape both of cartilage and tooth formation during craniofacial morphogenesis.

Animals↗
PubMed1991

Predicting elderly cardiac patients at risk for readmission.

Elder patients with cardiac disease are at high risk for physical deterioration during post hospital recovery and suffer frequent early readmission. It is important to identify such patients who frequently need help with discharge planning from social workers during their first admission. This study utilized computerized data on 628 patients, 238 of whom were readmissions. Question was raised as to what factors (functional, psychological, social and environmental), differentiated patients who were readmitted from those who were not. Using logistic regression, three variables: marital status, presence of coping difficulty and age of patients were identified as predictors of readmission within three months. Those who were married were less likely to be readmitted. Those with coping difficulties and older individuals were more likely to be readmitted. The accuracy of prediction, using these three factors, was 61 percent. Of those patients predicted as not being readmitted, sixty-nine percent were correctly predicted, while 39 percent were readmitted. Of patients predicted as readmissions, 49 percent were correctly predicted, while 51 percent were not. The major limitation of this study was that key physiological determinants of readmission were not collected. It is imperative that a valid screening device for predicting who is at risk for readmission should include physiological preconditions as well as functional and psychosocial data.

Adaptation, Psychological↗
PubMed1990

Screening elder cardiac patients to identify need for social work services.

Present screening methods to identify older patients in need of posthospital care planning are overly sensitive and lack specificity, with the rate of false-positive screenings reaching 65 percent. Research was undertaken to develop a computerized screening mechanism to identify elderly cardiac patients at high risk for posthospital care needs. Using the data from the Medicus Nursing Productivity and Quality of Patient Care Classification System (NPAQ) as potential predictive factors, the false-positive screening rate was reduced to 26 percent. Early and accurate identification of these patients may prove beneficial to patients and their families and to social workers and hospital administrators. It can improve social worker efficiency in developing and implementing an adequate posthospital care plan, thus enhancing patient recovery.

Aftercare↗
PubMed1990

Articulatory coding in prose reading: evidence from braille on changes with skill.

The role of speech-based strategies in prose reading was tested in two experiments with braillists at different levels of proficiency. Subjects read prose texts in silent and oral control conditions, under articulatory suppression, and while making non-speech movements during silent and oral reading, respectively. Experiment 1 used relatively difficult braille texts and showed that articulatory suppression reduced comprehension significantly compared to the other conditions. Speed (syllables per minute) was not significantly reduced under articulatory suppression, although two subjects were unable to read at all in that condition. Experiment 2 used easy texts and included beginning readers. Proficiency levels interacted significantly with experimental conditions for both speed and comprehension. The best readers showed no effect of articulatory suppression on either speed or comprehension with easy tests. Beginners showed significantly reduced speed and comprehension (or failed to score at all) under articulatory suppression, despite good comprehension in control conditions. For subjects in the middle groups, articulatory suppression had some effect on comprehension but speeded rather than slowed reading, if anything. The results suggest that articulatory suppression can affect input strategies as well as comprehension, but that the strategies which underly it vary with skill and test conditions. It was argued that suppression taps important but changing strategies in prose reading.

Adolescent↗
PubMed1989

Simultaneous reading with the two hands: reply to Bertelson and Mousty.

Bertelson and Mousty's criticisms of Millar's (1987) analyses rest on a misapprehension of the nature and purpose of the measures that were used. Millar (1987) used two measures to test a prediction from the hypothesis that fast braillists use the two hands to read different portions of text simultaneously. The study was not about scanning. Bertelson and Mousty's criticism and reanalysis of Millar's (1987) data is shown to be based on unsupported assumptions, and a misunderstanding of the first measure. Details about the first measure are given. It is shown that the findings from the two measures agree and are in the opposite direction to that predicted by the hypothesis. There could be a number of reasons for the difference between Bertelson et al. (1985) and Millar's (1987) data. They need further study.

Blindness↗
PubMed1987

The perceptual "window" in two-handed braille: do the left and right hands process text simultaneously?

The hypothesis that fluent braille readers use both hands simultaneously to read was tested. Video tape recordings of finger movements by ten students reading prose text were subjected to frame by frame analyses of synchronous finger positions. The hypothesis was not borne out. Touching a letter by one hand was paired most often with simultaneous touching of a space between letters or between words by the other hand. Simultaneous touching of letters by the two hands was least frequent and did not differ from simultaneous touching of gaps between letters. Further evidence against the hypothesis came from analyses of the time relations between the two hands at the beginning and end of lines. It was argued that fluency does not depend on simultaneous processing of the same type of information, but on fast intermittent alternation in function between the two hands.

Adolescent↗
PubMed1987

Perceptual and task factors in fluent braille.

Hypotheses that fluent braille depends (i) on coding letters by global outline shape for all task and speed levels, or (ii) on lateral dot-gap density scanning in fast reading for meaning were tested with three groups of fluent braillists who differed in reading speeds. In experiment 1, 90 degrees-rotated (near to far) texts under vertical and horizontal finger orientation were used. Hypothesis (i) was not supported. Finger orientation interacted significantly with Speed and Task. Vertical finger orientation, which disrupts lateral scanning, slowed reading for comprehension more than for letter search, and differentially more for faster readers. Horizontal finger orientation, which instead disrupts the familiar finger-body relation, did not have differential effects. The findings support hypothesis (ii). In experiment 2, normal texts and texts containing a degraded dot in some letters were used. These are felt in searching for individual letter patterns, but would disrupt lateral scanning of expected dot-gap density patterns in reading for meaning. The results supported the predictions from hypothesis (ii), that degraded texts slow reading for meaning significantly more than for letter search, and more in the case of faster readers than for the slowest group. Findings were not consistent with hypothesis (i), which predicts that text degradation affects tasks equally, and affects the slowest rather than the fastest readers. The results suggest that perceptual coding in reading differs with task demands and speed.

Adolescent↗
PubMed1986

Aspects of size, shape and texture in touch: redundancy and interference in children's discrimination of raised dot patterns.

Children discriminated tactual dot patterns by size or form and by texture. Adding irrelevant, easy, correlated texture cues improved size and form discrimination while orthogonal irrelevant texture cues interfered. Facilitation and interference could be reversed by reversing dimensional difficulty, but were found also when the two dimensions were equally accurate, for both blindfolded sighted and for blind children. The theoretical implication with regard to age effects, and practical implications for using dot numerosity and dot density differences for Braille learning were discussed.

Age Factors↗
PubMed1985

Segments of chromosomal DNA from Rhynchosciara americana that undergo additional rounds of DNA replication in the salivary gland DNA puffs have only weak ARS activity in yeast.

We have constructed a library of recombinant phage containing DNA from salivary gland chromosomes of Rhynchosciara americana. We have isolated phage from this library that carry sequences homologous to cDNA clones that hybridize in situ to the DNA puffs at the polytene chromosome regions C3 and C8. This has enabled us to demonstrate a 16-fold amplification of the genomic DNA sequences at these regions during DNA-puffing. At the C8 site there is a sequence element that has characteristics of 'scrambled' moderately repetitive DNA. This is located within 3 kb from the gene encoding a 1.95-kb mRNA. We have assayed restriction fragments from the two DNA puffs for Ars activity in yeast. The only strong Ars activity is associated with a part of the moderately repetitive DNA element from the C8 puff which is not present at this site in all animals.

Animals↗
PubMed1985

The perception of complex patterns by touch.

Two experiments are reported on matching Braille characters in dot pattern and outline shape formats by congenitally blind subjects. In a third experiment subjects' drawings of Braille shapes were analysed. Experiment 1 showed that normal and retarded readers differed significantly when outline shapes 'cued' identical dot patterns, but did not differ when the dot patterns preceded outlines. However, normal as well as retarded readers were faster and more accurate in judging identical pairs in dot-pattern format than in any other condition. In experiment 2 dot patterns and outline shapes were matched at three levels of reading proficiency. Faster readers made fewer errors in matching identical pairs, but all subjects were more accurate and faster with dot patterns than with outline shapes. Experiment 3 showed that blind subjects' drawing of outline shapes is not affected by reading proficiency. Most common were errors of alignment, including 'rotation' from vertical to horizontal axes, suggesting that sources of confusion were spatial position of dots and major axes of alignment rather than mirror-image reversals. It is argued that the results are not compatible with the hypothesis that Braille letters are perceived as global outline shapes by faster readers.

Adolescent↗