Biomedical subjects

D Ingram

Publications and source records attributed to D Ingram.

At least 19 recordsLinked to original sources

PubMed2006

Feline immunodeficiency virus and puma lentivirus in Florida panthers (Puma concolor coryi): epidemiology and diagnostic issues.

This study documents the seroprevalence of feline immunodeficiency virus (FIV) and puma lentivirus (PLV) in free-ranging and captive Florida panthers (Puma concolor coryi) (n = 51) and translocated Texas cougars (P. concolor stanleyana) (n = 10) from 1985 to 1998. The sera were tested for anti-FIV antibodies by enzyme-linked immunosorbent assay (ELISA) and Western blot tests. The ELISAs were read kinetically (KELA) and the sera were retrospectively examined by PLV peptide ELISA. Eleven panthers and one cougar were positive by KELA; 4 panthers and 4 cougars were equivocal; 35 panthers and 5 cougars were negative; and 1 panther had no data. Seven of the 11 KELA-positive panthers were also positive by Western blot tests and all but one were positive by PLV peptide ELISA. Ten KELA-negative and Western blot-negative cats, were positive by PLV peptide ELISA. KELA results varied within cats from one sample period to the next, but PLV peptide ELISA results were consistent. Territorial sympatry and mating behaviour, noted from radiotelemetry location data on the cats, may have contributed to viral transmission between seropositive animals. These findings suggest that Florida panthers and the introduced Texas cougars have been exposed to FIV and/or PLV.

Animals↗

PubMed2005

Neurofibromin and its inactivation of Ras are prerequisites for osteoblast functioning.

Skeletal problems and osteoporosis occur in up to 50% affected neurofibromatosis type 1 (NF1) humans. Inactivation of neurofibromin results in deregulation of Ras signal transduction. Little is known of bone biology in humans with NF1. The goal of our work was to determine if loss-of-function of Nf1 gene was associated with altered bone homeostasis and Ras signal transduction. Because homozygous Nf1 mice are embryonically lethal, heterozygote Nf1 (Nf1+/-) male mice were used to investigate skeletal phenotypes and osteoprogenitor functions, using standard in vivo and in vitro assays. We found that bone mass and geometry of Nf1+/- mice did not differ from wild type controls, despite a trend to less bone formation. Nf1+/- committed osteoprogenitors from femur metaphysis exhibited premature apoptosis and higher proliferation. Ras signaling was activated in primary Nf1+/- bone marrow-inducible osteoprogenitors. Inducible osteoprogenitors exhibited lower induction of osteoblast differentiation, assessed as alkaline phosphatase positive CFU-f. A screen of osteoblast marker genes showed a selective increase in osteopontin (OPN) mRNA and protein expression in these cells. OPN protein was increased in Nf1+/- bone, especially in cortical bone matrix. Because bone cell abnormalities in Nf1 haploinsufficiency were detected in vitro, redundant pathways must compensate for the deregulation of Ras signaling in vivo to maintain normal bone mass and function in vivo. Our in vitro data revealed that neurofibromin and its control of Ras signaling are required for osteoprogenitor homeostasis.

Animals↗

PubMed2005

Pathology reporting of breast cancer: trends in 1989-1999, following the introduction of mammographic screening in Western Australia.

BACKGROUND: A survey of pathology reporting of breast cancer in Western Australia in 1989 highlighted the need for improvement. The current study documents (1) changes in pathology reporting from 1989 to 1999 and (2) changes in patterns of histopathological prognostic indicators for breast cancer following introduction of mammographic screening in 1989. METHODS: Data concerning all breast cancer cases reported in Western Australia in 1989, 1994 and 1999 were retrieved using the State Cancer Registry, Hospital Morbidity data system, and pathology laboratory records. RESULTS: Pathology reports improved in quality during the decade surveyed. For invasive carcinoma, tumour size was not recorded in 1.2% of pathology reports in 1999 compared with 16.1% in 1989 (p<0.001). Corresponding figures for other prognostic factors were: tumour grade 3.3% and 51.6% (p<0.001), tumour type 0.2% and 4.1% (p<0.001), vascular invasion 3.7% and 70.9% (p<0.001), and lymph node status 1.9% and 4.5% (p = 0.023). In 1999, 5.9% of reports were not in a synoptic/checklist format, whereas all reports were descriptive in 1989 (p<0.001). For the population as a whole, the proportion of invasive carcinomas <1 cm was 20.9% in 1999 compared with 14.5% in 1989 (p<0.001); for tumours <2 cm the corresponding figures were 65.4% and 59.7% (p = 0.013). In 1999, 30.5% of tumours were histologically well-differentiated compared with 10.6% in 1989 (p<0.001), and 61.7% were lymph node negative in 1999 compared with 57.1% in 1989 (p = 0.006). Pure ductal carcinoma in situ (DCIS) constituted 10.9% and 7.9% of total cases of breast carcinoma in 1999 and 1989, respectively (p = 0.01). CONCLUSIONS: Quality of pathology reporting improved markedly over the period, in parallel with adoption of standardised synoptic pathology reports. By 1999, recording of important prognostic information was almost complete. Frequency of favourable prognostic factors generally increased over time, reflecting expected effects of mammographic screening.

Adenocarcinoma↗

PubMed2005

Security and confidentiality approach for the Clinical E-Science Framework (CLEF).

OBJECTIVES: CLEF is an MRC sponsored project in the E-Science programme that aims to establish methodologies and a technical infrastructure for the next generation of integrated clinical and bioscience research. METHODS: The heart of the CLEF approach to this challenge is to design and develop a pseudonymised repository of histories of cancer patients that can be accessed by researchers. Robust mechanisms and policies have been developed to ensure that patient privacy and confidentiality are preserved while delivering a repository of such medically rich information for the purposes of scientific research. RESULTS: This paper summarises the overall approach adopted by CLEF to meet data protection requirements, including the data flows, pseudonymisation measures and additional monitoring policies that are currently being developed. CONCLUSION: Once evaluated, it is hoped that the CLEF approach can serve as a model for other distributed electronic health record repositories to be accessed for research.

Access to Information↗

PubMed2004

Reduced breast cancer risk with increasing serum folate in a case-control study of the C677T genotype of the methylenetetrahydrofolate reductase gene.

Breast cancer risk may be associated with folate status or the C677T genotype of the methylenetetrahydrofolate reductase (MTHFR) gene. We compared serum folate concentrations and C677T genotype in 141 breast cancer patients and 109 age-matched controls. Serum folate was significantly lower in cases compared to controls (geometric means, 5.7 versus 6.6 microg/l; P=0.005). Breast cancer risk was not associated with C677T genotype. After adjusting for age of menarche, parity, alcohol intake and total fat intake we observed reductions in odds ratios for breast cancer risk comparing the highest with the lowest quartiles of serum folate concentrations of 0.23 (95% confidence interval (CI) 0.09, 0.54) for the entire group, 0.27 (CI 0.09, 0.80) for the wild-type and 0.08 (CI 0.01, 0.52) for the heterozygous C677T genotype. We conclude that for the whole group, and the wild-type and heterozygous C677T genotypes, increased serum concentrations of folate were associated with reduced risks of breast cancer.

Adult↗

PubMed2003

On-farm and postharvest processing sources of bacterial contamination to melon rinds.

Multistate and international foodborne illness outbreaks, particularly involving cantaloupe and often involving rare Salmonella spp., have increased dramatically over the past 13 years. This study assessed the sources and extent of melon rind contamination in production fields and at processing and packing facilities. In the spring of 1999, cantaloupe (Cucumis melo L. [reticulatus group] cv. Cruiser) sampled from two sites in the Rio Grande River Valley showed that postharvest-processed melon rinds often had greater plate counts of bacterial contaminants than field-fresh melons. Cantaloupe in the field had 2.5 to 3.5 log CFU g(-1) rind total coliforms by aerobic plate counts, whereas washed melons had 4.0 to 5.0 log CFU g(-1). In the fall of 1999, coliforms on honeydew melons (C. melo [inodorous group] cv. Honey Brew) ranged from 2.6 to 3.7 log CFU g(-1) after processing, and total and fecal coliforms and enterococci never fell below 2.5 log CFU g(-1). A hydrocooler at another site contaminated cantaloupe rinds with up to 3.4 log CFU g(-1) total and fecal enterococci; a secondary rinse with chlorinated water incompletely removed these bacteria. Sources of coliforms and enterococci were at high levels in melon production soils, especially in furrows that were flood irrigated, in standing water at one field, and in irrigation water at both sites. At one processing facility, wash water pumped from the Rio Grande River may not have been sufficiently disinfected prior to use. Because soil, irrigation water, and process water were potential sources of bacterial contamination, monitoring and management on-farm and at processing and packing facilities should focus on water quality as an important control point for growers and packers to reduce bacterial contamination on melon rinds.

Colony Count, Microbial↗

PubMed2002

Areolar discharge and peri-areolar breast cysts in adolescent females.

Nipple discharge in adolescents is well documented, and usually results from endocrine dysfunction or local breast disease. Areolar discharge, however, in healthy adolescent girls is a rare finding, and is sometimes associated with peri-areolar lumps. These patients usually present with painless discharge from around the nipple, and sometimes with a lump at the site. Some patients present with a lump only, and secondary inflammation at the site can occur. Although the lesions often resolve spontaneously, they can recur, and the treatment options are discussed. There are very few cases in the literature of areolar discharge in young girls, which perhaps reflects its incidence. The following case report of 16 patients appears to be the largest collection of patients reported with this apparently benign condition. Ultrasound examination is a useful tool in the diagnosis of this condition. Fine needle aspiration was sometimes curative, but surgical excision appeared definitive therapy.

Journal Article↗

PubMed2002

Information architecture for a federated health record server.

This paper describes the information models that have been used to implement a federated health record server and to deploy it in a live clinical setting. The authors, working at the Centre for Health Informatics and Multiprofessional Education (University College London), have built up over a decade of experience within Europe on the requirements and information models that are needed to underpin comprehensive multi-professional electronic health records. This work has involved collaboration with a wide range of health care and informatics organisations and partners in the healthcare computing industry across Europe though the EU Health Telematics projects GEHR, Synapses, EHCR-SupA, SynEx and Medicate. The resulting architecture models have fed into recent European standardisation work in this area, such as CEN TC/251 ENV 13606. UCL has implemented a federated health record server based on these models which is now running in the Department of Cardiovascular Medicine at the Whittington Hospital in North London. The information models described in this paper reflect a refinement based on this implementation experience.

Computer Communication Networks↗

PubMed2001

Laryngostroboscopic, acoustic, and environmental characteristics of high-risk vocal performers.

Vocal performance often requires excessively high vocal demand. In particular "high-risk" performers, a group of individuals who use their voices at their maximum effort level, are often exposed to unique vocal abuse characteristics which include high environmental and performance demands and inconsistencies of cast performance. Three categories of high-risk performers were studied: musical theater, choral ensemble, and street theater. Musical theater performers produce a Broadway, West End "belting" style voice. Street theater performers use a high-energy pitch varying dialogue in order to imitate a desired character voice. Choral ensemble performance requires group cohesion and blending of four-part harmony. The melodies require sustained vocal durations within each of the respective registers. For each of these studied groups vocal tasks of sustained production of /i/ and /a/ were subjected to analysis. Acoustic measures included fundamental frequency, standard deviation of fundamental frequency, jitter percent, shimmer percent, and noise-to-harmonic ratio. Laryngostroboscopic parameters were assessed during sustained /i/. Environmental acoustic sound field measurements were made using an A weighting and linear weighting sound pressure level. These weightings were used to describe noise levels and vocal output, respectively, within the performance environments. Results of the analysis suggest that high-risk performers are a unique performance type defined by distinctive, acoustic, laryngostroboscopic, and environmental characteristics.

Adolescent↗

PubMed2001

Volume of activation of the Hering-Breuer inflation reflex in the newborn infant.

Although the Hering-Breuer inflation reflex (HBIR) is active within tidal breathing range in the neonatal period, there is no information regarding whether a critical volume has to be exceeded before any effect can be observed. To explore this, effects of multiple airway occlusions on inspiratory and expiratory timing were measured throughout tidal breathing range using a face mask and shutter system. In 20 of the 22 healthy infants studied, there was significant shortening of inspiration because the volume at which occlusion occurred rose from functional residual capacity (FRC) to end-inspiratory volume [14.9% reduction in inspiratory time (per ml/kg increase in lung volume at occlusion)]. All infants showed a significant increase in expiratory time [17.1% increase (per ml/kg increase in lung volume at occlusion)]. Polynomial regression analyses revealed a progressive increase in strength of HBIR from FRC to approximately 4 ml/kg above FRC. Eighteen infants showed no further shortening of inspiratory time and 10 infants no further lengthening of expiratory time with increasing occlusion volumes, indicating maximal stimulation of the reflex had been achieved. There was a significant relationship between strength of HBIR and respiratory rate, suggesting that HBIR modifies the breathing pattern in the neonatal period.

Humans↗

PubMed2001

Response of cotton to prebloom square loss.

In 1996 and 1997, various intensities of prebloom square removal were applied to three cultivars of cotton grown in Mississippi. With the exception of one cultivar in 1997, all cultivars were B. thuringiensis (Bt)-transgenic cotton. At harvest, the number of bolls and seed cotton weight was recorded for all plants in each square removal treatment. All cultivars responded similarly to square loss. A yield increase (overcompensation) was observed in the treatment where all squares were removed from the plant one week after squaring began. Only the treatment where all squares were removed before bloom significantly reduced yield and caused a large (>7 d) delay in crop maturation. Otherwise, moderate levels of square removal (approximately 20-50% of prebloom squares) had little impact on overall lint production. However, the patterns of cotton production on the plants were significantly influenced by the square removal treatments. The removal of relatively more or larger squares increased seed cotton production in late-season fruiting cohorts and on 'vegetative' branches. Compensation for square loss occurred by increasing the relative number and weight of bolls produced subsequent to early-season square removal. Typically, early-season square loss increased the value of later-season fruiting cohorts, especially the midseason cohorts and bolls on vegetative branches. The implications of prebloom square loss, including the compensatory ability of the cotton plant, on insect management are discussed.

Animals↗

PubMed2000

Program for testing biological interventions to promote healthy aging.

The National Institute on Aging (NIA) sponsored a workshop on September, 1999 to discuss the feasibility of establishing a program to evaluate potential intervention strategies to decelerate the rate of aging in mammals. The ultimate goal is to identify promising interventions in animals that might lead to clinical trials in humans. The participants discussed various animal models, biological endpoints and possible structure of such a program. The ability to implement such a program will require a decision by NIA staff about whether the anticipated benefits to be derived from identification of effective interventions under well controlled conditions in an animal model, in this case the mouse, would justify the anticipated cost of the testing program.

Aging↗

PubMed2000

Double binds and the reproductive and mothering experiences of HIV-positive women.

In spite of the increasing number of young women infected with HIV in the United States, little is known about the reproductive and mothering experiences of these women. The purpose of the grounded-theory research discussed in this article was to describe the reproductive and mothering experiences of HIV-positive women. Twenty HIV-positive women participated in 31 in-depth interviews. The grounded-theory method was used for data analysis. A communication pattern known in the psychiatric literature as a double bind was discovered to be a basic social psychological problem that affected the women's experiences with reproduction and mothering. An understanding of the power and influence of these double binds permits health care professionals to plan patient-centered programs and to individualize care specifically for HIV-positive women.

Adaptation, Psychological↗

PubMed1999

Effects of different modes of delivery on lung volumes of newborn infants.

The aim of our study was to examine the effect of labor and birth canal compression on the rate of clearance of lung fluid. We recruited 10 babies born by vaginal delivery and 10 born by elective cesarean section (ECS). Thoracic gas volume (TGV) was measured using total body plethysmography, and functional residual capacity (FRC) by argon dilution, at ages 4-6 h and 24 h. Additional measurements were obtained at age 48 h in the infants born by ECS. Our results showed significant increases in mean TGV (from 23.1 mL/kg to 27.4 mL/kg, P = 0.002) and FRC (from 21.2 mL/kg to 24.1 mL/kg, P = 0.04) between 4-6 h and 24 h of age after ECS delivery. Lung volumes did not change significantly over the next 24 h (TGV, 27.4 mL/kg, P = 0.97; FRC, 25.5 mL/kg, P = 0.42). In those infants born by vaginal delivery, the mean TGV at 4-6 h and 24 h were 26.7 and 28.7 mL/kg, respectively (P = 0.09), and the mean FRC results were 23.1 and 24.9 mL/kg, respectively, P = 0.08). The TGV tended to be lower at 4-6 h in those born by ECS than in infants born vaginally (23.1 vs. 26.7 mL/kg, P = 0.05). We conclude that there is a delay of up to 24 h in the establishment of final lung volumes in babies born without exposure to labor or passage through the birth canal, and that this may explain the increased respiratory morbidity associated with delivery by ECS.

Birth Weight↗

PubMed1999

A randomized comparison of home uterine activity monitoring in the outpatient management of women treated for preterm labor.

OBJECTIVE: The aim of the study was to evaluate home uterine activity monitoring as an intervention in reducing the rate of preterm birth among women treated for preterm labor. STUDY DESIGN: A total of 186 women were treated in the hospital with magnesium sulfate for preterm labor and were prospectively randomly assigned to study groups; among these, 162 were ultimately eligible for comparison. Eighty-two of these women were assigned to the monitored group and 80 were assigned to an unmonitored control group. Other than monitoring, all women received identical prenatal follow-up, including daily perinatal telephone contact and oral terbutaline therapy. Outcome comparisons were primarily directed toward evaluation of preterm birth at <35 weeks' gestation. Readmissions for recurrent preterm labor and observations lasting <24 hours were evaluated in monitored and unmonitored groups. Compliance with monitoring was also evaluated in the monitored group. RESULTS: The monitored and control groups were demographically similar. According to a multivariate logistic regression model, women with cervical dilatation of >/=2 cm were 4 times more likely to be delivered at <35 weeks' gestation (P <.05). Gestational ages at delivery were similar in the monitored and control groups. There was no significant difference in the overall rate of preterm delivery at <35 weeks' gestation between the monitored group (10.9%) and the control group (15.0%). The overall rates of delivery at <37 weeks' gestation were high (48.8% and 60.0% for monitored and control groups, respectively), and the difference was not significant. The numbers of women with >/=1 instance of readmission and treatment for recurrent preterm labor were equal in the monitored and control groups. The numbers of women with >/=1 hospital observation lasting <24 hours were not different between the groups. Compliance with monitoring did not significantly differ for women who were delivered at <35 weeks' gestation, women with >/=2 cm cervical dilatation at enrollment, or for African American women. CONCLUSION: A reduction in the likelihood of preterm delivery at <35 weeks' gestation was not further enhanced by the addition of home uterine monitoring to the outpatient management regimens of women treated for preterm labor.

Adolescent↗

PubMed1999

Management of breast cancer in the elderly by complete local excision and tamoxifen alone.

BACKGROUND: Breast cancer in the elderly is a significant problem, with approximately 30% of all breast cancers occurring in women who are aged 70 or more. Treatments such as axillary dissection, radiotherapy and chemotherapy, part of standard therapy in younger women, have a considerable morbidity and may not be well tolerated in the elderly. The authors report their experience with a more conservative approach to breast cancer in the elderly, using complete local excision combined with long-term tamoxifen (CLE and Tam). METHODS: Seventy women aged > or = 70 years (median age: 79.5 years; range: 70-93 years) were treated by CLE and Tam, and were followed for a median of 25 months (range: 1-82 months). The study population of 70 women represented a less fit group, with tumours suitable for a breast-conserving approach and without palpable axillary lymph nodes. Follow-up was by clinical examination and annual mammography. RESULTS: Loco-regional failure occurred in seven women (10%), three of which involved the breast alone, three the axilla alone, and one involved both sites. Five patients had further surgery. Six of the seven patients had high-grade tumours and two of them were oestrogen receptor-negative. Four of the failure group have subsequently died: two with metastatic breast cancer and two from non-malignant disease. Of the whole study group, there have been 12 deaths in the follow-up period: three from metastatic breast cancer and nine from unrelated medical illness. CONCLUSIONS: It is believed that CLE and Tam provide a simple and safe approach for early non-high-grade breast cancers in elderly women. By such an approach, a large number of elderly women can avoid axillary dissection and radiotherapy.

Aged↗

PubMed1999

Determination of resonance frequency of the respiratory system in respiratory distress syndrome.

AIM: To measure tidal volume delivery produced by high frequency oscillation (HFO) at a range of frequencies including the resonance frequency. METHODS: Eighteen infants with respiratory distress syndrome were recruited (median gestation 28.7 weeks). Each was ventilated at frequencies between 8 and 30 Hertz. Phase analysis was performed at various points of the respiratory cycle. HFO was provided by a variable speed piston device. Resonance frequency was determined from the phase relation between the cyclical movements of the piston and pressure changes at the airway opening. Tidal volume was measured using a jacket plethysmograph. RESULTS: The results were most reproducible when analysis was performed at the end of inspiration (within 1 Hz in nine out of 10 cases). Comparison between tidal volume delivery at 10 Hz and resonance frequency was made in 10 subjects. Delivery was significantly higher at resonance than at 10 Hertz (mean percentage increase 92%, range 9-222%). CONCLUSIONS: These preliminary findings suggest that there is improved volume delivery at resonance frequency.

Airway Resistance↗

PubMed1999

Assessment of effect of nasal continuous positive pressure on laryngeal opening using fibre optic laryngoscopy.

AIM: To assess the effect of nasal continuous positive airways pressure (CPAP) on the dimensions of the laryngeal opening. METHODS: Nine preterm infants who had previously received ventilatory support for respiratory distress syndrome (RDS) were studied. All were receiving nasal CPAP. The laryngeal opening was visualised using a fibre optic video camera system. The ratio of width to length of the opening was measured on and off CPAP. RESULTS: In eight of the infants the width: length ratio increased on CPAP; mean change for group +24.4% (95% CI +11.9 to +37.9). CONCLUSIONS: Nasal CPAP seems to dilate the larynx. This may explain the selective beneficial effects of CPAP on mixed and obstructive apnoea.

Apnea↗