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M Hall

Publications and source records attributed to M Hall.

At least 109 records · Page 6Linked to original sources
PubMed1997

Catamenial variations in erythrocyte sodium-lithium countertransport and blood pressure.

1. We undertook a temporal study of external sodium-stimulated lithium efflux (sodium-lithium countertransport) in erythrocytes and blood pressure by measuring these two parameters in three phases of the menstrual cycle (menstrual, midcycle and luteal phases) in 22 healthy, non-medicated females with regular menstrual cycles. Plasma oestradiol and progesterone levels were also determined. 2. Sodium-lithium countertransport activity (activity in 140 mmol/l external NaCl) in the midcycle phase (0.176 +/- 0.017 mmol h-1 l-1 of cells) was lower than in the menstrual (0.192 +/- 0.016 mmol h-1 l-1 of cells, P < 0.030) and luteal (0.203 +/- 0.018 mmol h-1 l-1 of cells, P < 0.030) phases. The Vmax of the transporter changed similarly but the K(m) was unaltered. 3. The plasma oestradiol level was 628.9 +/- 39.1 pmol/l in the midcycle phase, higher than in the menstrual (232 +/- 18.5 pmol/l, P < 0.001) and luteal (372.5 +/- 28.1 pmol/l, P < 0.001) phases. The progesterone level was 28.6 +/- 2.1 nmol/l in the luteal phase, and values were lower in the menstrual (2.5 +/- 0.3 nmol/l, P < 0.001) and midcycle (2.8 +/- 0.4 nmol/l, P < 0.001) phases. 4. There was no correlation between plasma oestradiol and sodium-lithium countertransport activity or Vmax during the menstrual cycle, but plasma progesterone was positively correlated with sodium-lithium countertransport activity (r = 0.478, P < 0.025, n = 22) and Vmax (r = 0.551, P < 0.045, n = 14) in the luteal phase. 5. Systolic blood pressure did not change significantly during the menstrual cycle. However, the diastolic pressure showed variation similar to that in sodium-lithium countertransport activity/Vmax, its midcycle value of 66.6 +/- 1.4 mmHg being lower than that in the luteal (71.6 +/- 1.3 mmHg, P < 0.025) and menstrual (70.6 +/- 1.4 mmHg, P < 0.025) phases. 6. We conclude that sodium-lithium countertransport activity exhibits catamenial variation. Therefore we suggest, given this observation, that blood sampling for the assessment of the state of activity of the transport system be standardized in relation to a phase of the menstrual cycle in future studies involving females.

Adult↗
PubMed1997

Animal serum-free culture of purified human CD34+ cells: amplification of progenitors from G-CSF and GM-CSF-mobilized peripheral blood.

The isolation and culture of human CD34+ cells could have broad clinical application for hematologic support following high-dose chemotherapy or bone marrow transplantation. The need for reproducible, animal product-free conditions for the culture of progenitors is crucial to the widespread clinical implementation of ex vivo cell therapies. In these studies, we explored the use of animal serum-free (ASF) medium for the culture of isolated human bone marrow and peripheral blood CD34+ cells. In this ASF system, isolated CD34+ cells were cultured using a variety of different growth factor combinations. Such ASF culture conditions yielded equivalent to superior cell and progenitor growth when directly compared with culture containing 10% fetal calf serum (FCS). In cultures containing IL-1, IL-3, and stem cell factor, total cell numbers increased, on average, 33-fold over the first 2 weeks. On phenotypic analysis, the ASF cultures demonstrated sustained proliferation of CD33+ myeloid cells throughout the culture period. CD34+ cell numbers increased during the first 7-10 days of culture, with a mean 3.4-fold expansion. Concomitant with the CD34+ cell expansion was an average 8.2-fold expansion of colony-forming unit-granulocyte-macrophage (CFU-GM) and a 102.0-fold increase in burst-forming units-erythrocytes (BFU-E). Likewise, a mean 4929-fold expansion of CD41a+ megakaryocyte progenitors was observed in these CD34+ cultures. Different combinations of growth factors affected the fold increase in cell and progenitor number. When CD34+ cell cultures from normal healthy volunteers mobilized with either G-CSF or GM-CSF were compared, similar expansions of total cell and progenitor cells resulted. However, CD41+ cells expansions were greater in those samples from G-CSF-mobilized volunteers in every case tested. These studies established the feasibility of this ASF CD34+ cell culture system to generate a population of maturing progenitors for potential use in transfusion support during cytopenic periods following high-dose chemotherapy or bone marrow transplantation.

Animals↗
PubMed1997

Filamentous growth of the budding yeast Saccharomyces cerevisiae induced by overexpression of the WHi2 gene.

The WHI2 gene of the budding yeast Saccharomyces cerevisiae is required for the arrest of cell proliferation upon nutrient exhaustion: whi2 mutants carry on dividing and in the absence of growth become abnormally small. It is reported here that overexpression of Whi2 from the GAL1 promoter results in filamentous growth - cells fail to complete cytokinesis, the budding pattern changes from axial to polar, cells become elongated and cell size increases threefold. In many ways, these filaments resemble the pseudohyphae which result from nitrogen-limited growth and the filaments seen during the invasive growth of haploids. However, Whi2-induced filament formation is reduced, but not blocked, by mutations in STE7, STE12 or STE20 which do block pseudohypha formation. Furthermore, pseudohypha formation can still occur in a diploid in which both copies of the WHI2 gene have been deleted. Thus Whi2-induced filament formation and pseudohypha formation must come about through the action of different pathways. Despite this, a mutation in the STE11 gene, which is required for pseudohypha formation, does block Whi2-induced filament formation. Concanavalin A pulse-chase experiments show that new cell wall material is incorporated only into the tips of the apical cells. An extragenic suppressor of the Whi2 allele also results in filamentous growth. These results suggest that Whi2 negatively regulates a function required for the budding mode of cell proliferation including cytokinesis. This function is defined wholly or in part by the fsw1 allele.

Cell Cycle Proteins↗
PubMed1997

Urinary tract injuries during obstetric intervention.

A retrospective case record review of obstetric urinary tract injury in the Grampian region from 1976 to 1993 identified 16 cases of bladder injury (0.1 per 1000 deliveries, 1.4 per 1000 caesarean sections and four cases of ureteric injury (0.03 per 1000 deliveries, 0.27 per 1000 caesarean sections). Diagnosis of bladder injury was immediate, but of ureteric injury often delayed. Although the injury rates are lower than previously reported and previously reported risk factors not confirmed, this audit has resulted in guidelines for junior staff, compliance with which will be monitored, and every case of urinary tract injury will be reviewed.

Cesarean Section↗
PubMed1997

Sport and diabetes.

Explore the source record for details and available documents.

Diabetes Mellitus↗
PubMed1997

Urinary excretion of 5-L-oxoproline (pyroglutamic acid) during early life in term and preterm infants.

Urinary 5-L-oxoproline was measured in term and preterm infants from shortly after birth until 6 weeks of postnatal age to determine their ability to synthesise glycine. In term infants the excretion was five to 10 times that seen in normal adults, increasing from 105 mumol/mmol creatinine in the first 72 hours after birth to 170 mumol/mmol creatinine at 6 weeks of age. There was a significant inverse linear correlation between the excretion of 5-L-oxoproline and length of gestation or birthweight. By 6 weeks of age there was no longer a significant difference in 5-L-oxoproline between term and preterm infants. There was no difference in the excretion of 5-L-oxoproline between boys and girls, or between infants fed on human milk or an artificial formula. If, in part, variability in the excretion of 5-L-oxoproline is determined by the extent to which the endogenous formation of glycine is adequate, then glycine formation may be marginal during early life, more so in preterm than in term infants, providing additional evidence that glycine is a conditionally essential amino acid in the neonate.

Birth Weight↗
PubMed1997

The PRECEDE-PROCEED model: application to planning a child pedestrian injury prevention program.

OBJECTIVES: The objectives were first, to modify the PRECEDE-PROCEED model and to use it is as a basis for planning a three year intervention trial that aims to reduce injury to child pedestrians. A second objective was to assess the suitability of this process for planning such a relatively complex program. SETTING: The project was carried out in 47 primary schools in three local government areas, in the Perth metropolitan area. METHODS: The program was developed, based on extensive needs assessment incorporating formative evaluations. Epidemiological, psychosocial, environmental, educational, and demographic information was gathered, organised, and prioritised. The PRECEDE-PROCEED model was used to identify the relevant behavioural and environmental risk factors associated with child pedestrian injuries in the target areas. Modifiable causes of those behavioural and environmental factors were delineated. A description of how the model facilitated the development of program objectives and subobjectives which were linked to strategy objectives, and strategies is provided. RESULTS: The process used to plan the child pedestrian injury prevention program ensured that a critical assessment was undertaken of all the relevant epidemiological, behavioural, and environmental information. The gathering, organising, and prioritising of the information was facilitated by the process. CONCLUSIONS: The use of a model such as PRECEDE-PROCEED can enhance the development of a child injury prevention program. In particular, the process can facilitate the identification of appropriate objectives which in turn facilitates the development of suitable interventions and evaluation methods.

Accident Prevention↗
PubMed1997

Can careful ultrasound examination of the urinary tract exclude vesicoureteric reflux in the neonate?

The aim of the study was to determine whether a urinary tract appearing normal when assessed by meticulous ultrasound (US) examination may coexist with vesicoureteric reflux (VUR) and whether a normal US scan can be used to exclude VUR, thereby avoiding unnecessary voiding cystourethrography (VCUG). The US features of 35 neonates with known VUR were reviewed. Criteria studied included pelvic dilatation above 7 mm on a transverse scan, calyceal or ureteral dilatation, pelvic or ureteral wall thickening, absence of the corticomedullary differentiation (CMD) and signs of renal dysplasia (small kidney, thinned or hyperechoic cortex and cortical cysts); all signs that have been shown to result from or to be associated with VUR. 57 refluxing renal units (RRU) were found among the 35 patients. VUR was bilateral in 22. Among the 57 RRU, at least one US anomaly that would have prompted VCUG was present in 50 (87.7%). Pelvic dilatation above 7 mm was present in 29 RRU (50.9%) only. Calyceal dilatation was present in 24 RRU, the dilatation involving the calyces but not the renal pelvis in seven. Ureteral dilatation was observed in 15 RRU. Pelvic or ureteral wall thickening was present in seven RRU. CMD was absent in 32 RRU (56.1%). US signs of dysplasia were found in 19 RRU. No US anomaly was found in seven RRU (12.3%) in six patients. A careful and meticulous US examination of the neonatal urinary tract allows the detection of over 87% of RRU by showing at least one sonographic abnormality. It is concluded that a normal appearing urinary tract on US does not usually coexist with VUR and that in such cases VCUG is not necessary.

Dilatation, Pathologic↗
PubMed1997

Impact of growth hormone treatment on a Belgian population of short children with renal allografts.

We retrospectively analyzed the effects of recombinant human growth hormone (rhGH) in a Belgian population of 36 short children with renal allografts. Seven children were dropped from the growth study: 1 had skeletal dysplasia and in 6 cases rhGH was given for less than 1 yr (1 died, 1 developed genu valgum, 2 were non-compliant and 2 grafts deteriorated). Final height was reached in 17 patients, and 12 children were still growing at the end of the study. Median height standard deviation score (SDS) in the 29 patients was -2.3 at the time of transplantation, and -2.7 when rhGH therapy was initiated. During rhGH therapy (median duration 3.2 yr, range 0.6-7.7 yr), height SDS increased by a mean of 0.4 per year, and bone maturation was not accelerated. Final height reached was 162.7 (149.0-169.5) cm (median SDS -1.8) in males and 151.0 (130.5-169.5) cm (median SDS -1.9) in females. Final height is significantly greater in males than females compared with a historical control group of untreated patients. Final height is within the parental target height range in 6 out of the 17 patients. The increase in height SDS in patients who were at an advanced stage of puberty (Tanner stages 4-5) when rhGH therapy was initiated exceeded our expectations (mean height gain 14.2 cm in boys and 10 cm in girls). In the cohort of 36 children, 4 patients developed an acute allograft rejection, all of whom had an underlying chronic rejection. This resulted in 3 graft losses within 5 yr. Our results indicate that rhGH treatment has a positive effect in short children with renal allografts, even if it is started in late puberty. In the presence of underlying chronic rejection, rhGH treatment needs careful monitoring to minimize the risk of graft loss.

Adolescent↗
PubMed1997

When resources are scarce: the impact of three organizational practices on clinician-managers.

Clinician-managers (CMs) are becoming increasingly responsible for resource allocation decisions, decisions that can spawn ethical issues when resources are scarce. The purpose of the study on which this article is based was to determine which factors would predict CMs' satisfaction with organizational practices that assist them with ethical issues arising from resource allocation decisions.

Analysis of Variance↗
PubMed1997

Minor burns and hand burns: comparing treatment methods.

As nurse-led wound management increases, nurses need to maintain research-based practice. Water vapour-permeable fabrics cause less accumulation of fluid than polythene when used in minor burns. Honey has been used in wound cleansing for many years.

Bandages↗
PubMed1997

The posttreatment illness course of depression in bereaved elders. High relapse/recurrence rates.

Losing close attachments through death in late life is common and can lead to depression. Previous work has shown the clinical benefits of treating these depressions. This article describes the 2-year course of 53 elderly subjects with bereavement-related depression after responding to various treatments. Forty-six patients experienced a full response to acute treatment, but 36% experienced relapse or recurrence. This finding suggests that the treatment response in depressed bereaved older patients is more brittle than expected.

Aged↗
PubMed1997

Regulation and function of the cyclin-dependent kinase inhibitor p16CDKN2.

Many human tumours show perturbations of a pathway that includes the D-cyclins, their associated cyclin-dependent kinases, and specific kinase inhibitors. The focal point of this pathway is the product of the retinoblastoma tumour suppressor gene, pRb, which imposes a block on G1 phase progression. Thus, the major role of the cyclin D-dependent kinases is to overcome this block by initiating the phosphorylation of pRb. Excessive activity of this pathway is likely to lead to excessive cell proliferation. Conversely, accumulation of the inhibitors is associated with the cessation of cell division.

Carrier Proteins↗
PubMed1997

Intrusive thoughts and avoidance behaviors are associated with sleep disturbances in bereavement-related depression.

Cognitive arousal has been associated with disrupted sleep in individuals with insomnia and may be one mechanism underlying sleep disturbances in depression. We evaluated the relationship of sleep to bereavement-related intrusive thoughts and avoidance behaviors in 40 men and women with major depression consequent to bereavement. Mean subject age was 65 years, 25% of the same was male, and median time since loss was 7.4 months. Levels of intrusive thoughts and avoidance behaviors were similar to samples seeking treatment for stress response syndromes, including post-traumatic stress disorder. After controlling for the effects of age, time since loss, and depression severity, greater frequency of bereavement-related intrusive thoughts and avoidance behaviors was associated with longer sleep latency and lower delta sleep ratio (P values < .01). Intrusive thoughts and avoidance behaviors were not strongly related to gender, time since loss, depression severity, or subjective sleep quality. These results suggest that intrusive thoughts and avoidance behaviors affect sleep in bereavement-related depression and may therefore be related to the clinical course of depression.

Aged↗
PubMed1996

Genetic correlation of inhibitory gating of hippocampal auditory evoked response and alpha-bungarotoxin-binding nicotinic cholinergic receptors in inbred mouse strains.

One function of the hippocampus is to ascertain the novelty of incoming sensations and encode significant new information into memory. The regulation of response to repeated stimuli may prevent overloading of this function by redundant sensory input. Recent pharmacological studies implicate the role of alpha-bungarotoxin-sensitive nicotinic cholinergic receptors in the inhibition of hippocampal response to repeated auditory stimuli. The number of hippocampal alpha-bungarotoxin-sensitive receptors has a major genetic determinant, as demonstrated by a significant variance between different inbred mouse strains. The purpose of the present study was to determine whether there was a related genetic correlation for the gating of auditory response. Nine inbred mouse strains, representing a continuum of hippocampal alpha-bungarotoxin binding, were tested for the electrophysiological response to repeated auditory stimulation, followed by whole hippocampus membrane alpha-bungarotoxin binding studies. Several parameters of the auditory evoked response showed significant genetic variance over the nine strains, and a significant correlation was found between hippocampal alpha-bungarotoxin binding and both the amplitude of the initial evoked response and its inhibition to repeated auditory stimuli. There was no correlation of the auditory evoked response with high-affinity nicotine binding. These data further support the hypothesis that alpha-bungarotoxin-sensitive nicotinic receptors are involved in the regulation of hippocampal response to repeated auditory stimuli and suggest that this function is genetically controlled.

Acoustic Stimulation↗