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Biomedical subjects

B Moore

Publications and source records attributed to B Moore.

At least 19 recordsLinked to original sources
PubMed2005

Earth-mass dark-matter haloes as the first structures in the early Universe.

The Universe was nearly smooth and homogeneous before a redshift of z = 100, about 20 million years after the Big Bang. After this epoch, the tiny fluctuations imprinted upon the matter distribution during the initial expansion began to collapse because of gravity. The properties of these fluctuations depend on the unknown nature of dark matter, the determination of which is one of the biggest challenges in present-day science. Here we report supercomputer simulations of the concordance cosmological model, which assumes neutralino dark matter (at present the preferred candidate), and find that the first objects to form are numerous Earth-mass dark-matter haloes about as large as the Solar System. They are stable against gravitational disruption, even within the central regions of the Milky Way. We expect over 10(15) to survive within the Galactic halo, with one passing through the Solar System every few thousand years. The nearest structures should be among the brightest sources of gamma-rays (from particle-particle annihilation).

Journal Article↗
PubMed2003

Electroencephalograph effects of single doses of Ginkgo biloba and Panax ginseng in healthy young volunteers.

Both Ginkgo biloba and Panax ginseng exert a number of physiological effects and have been shown to modulate aspects of cognitive performance. Whilst a number of studies have examined ginkgo's effects on electroencephalograph (EEG) recordings, to date, none have investigated the EEG effects of ginseng. In this double-blind, placebo-controlled, balanced crossover experiment, the effects of single doses of G. biloba (360 mg GK501), P. ginseng (200 mg G115), and an identical placebo, on auditory-evoked potentials, contingent negative variation (CNV), and resting power within the delta, theta, alpha, and beta wavebands, were assessed in 15 healthy volunteers. Each participant was assessed on three separate occasions 4 h after consuming that day's treatment. The order of presentation of the treatments was dictated by a Latin square with 7 days between testing sessions. The results showed that ginseng led to a significant shortening of the latency of the P300 component of the evoked potential. Both ginseng and ginkgo also led to significant reductions in frontal 'eyes closed' theta and beta activity, with additional reduction for ginseng in the alpha waveband. These findings demonstrate for the first time that P. ginseng can directly modulate cerebroelectrical activity, and that these effects are more pronounced than those following G. biloba.

Adult↗
PubMed2003

The marrow stem cell: the continuum.

The marrow hematopoietic stem cell is currently being redefined as to all aspects of its phenotype and its total differentiation capacity. This redefinition now includes its plasticity as to production of nonhematopoietic and hematopoietic cell types, the determinants of its in vivo engraftment potential and its expression of stem cell functional characteristics.

Animals↗
PubMed2003

Marrow stem cell potential within a continuum.

On the basis of our studies of the fluctuation of the hematopoietic stem cell phenotype with cell cycle trnsit, we hypothesize that the ability of marrow stem cells to convert to nonhematopoietic cells will also vary at different points in the cell cycle. The new biology of stem cells has an impact on many fields including developmental biology and stem cell biology and the clinical potential is enormous.

Animals↗
PubMed2002

Projecting the future of the U.S. carbon sink.

Atmospheric and ground-based methods agree on the presence of a carbon sink in the coterminous United States (the United States minus Alaska and Hawaii), and the primary causes for the sink recently have been identified. Projecting the future behavior of the sink is necessary for projecting future net emissions. Here we use two models, the Ecosystem Demography model and a second simpler empirically based model (Miami Land Use History), to estimate the spatio-temporal patterns of ecosystem carbon stocks and fluxes resulting from land-use changes and fire suppression from 1700 to 2100. Our results are compared with other historical reconstructions of ecosystem carbon fluxes and to a detailed carbon budget for the 1980s. Our projections indicate that the ecosystem recovery processes that are primarily responsible for the contemporary U.S. carbon sink will slow over the next century, resulting in a significant reduction of the sink. The projected rate of decrease depends strongly on scenarios of future land use and the long-term effectiveness of fire suppression.

Agriculture↗
PubMed2002

HIV multidisciplinary teams work: support services improve access to and retention in HIV primary care.

The multidisciplinary team model of HIV care evolved out of necessity due to the diverse characteristics and needs of people living with HIV disease. Though it is now accepted as the international standard of care, it represents a significant departure from methods of care for other infectious diseases, and debate continues regarding the effectiveness of its interventions. The debate has been largely uninformed by data; for example, little is known about the relationship between ancillary support services and primary care outcomes. We hypothesized that support services increase access to and retention in HIV primary care in an inner city public hospital clinic. We conducted a retrospective analysis of clinical data sets on 2,647 patients at the CORE Center, Chicago from 1997-1998 to investigate the relationship between four support services-case management (CM), transportation (TRANS), mental health (MH) and chemical dependency (CD)-and access to and retention in HIV primary care. We found that patients who received each of these services were significantly more likely to receive any care, regular care and had more visits than patients with no service, and retention increased by 15-18%. Female gender, younger age, self-pay status and IDU predicted less regular care. Need for all services was substantial and significantly greater in women. Outcomes improved to the greatest extent among patients who needed and received each service. We conclude that support services significantly increased access to and retention in HIV primary care. Our findings validate the multidisciplinary team model of HIV care, and suggest that health services that are tailored to the express needs of patients lead to better care and improved health outcomes. Further testing of changes in health care delivery to meet the rapidly changing needs of people living with HIV disease and respond to the constantly changing practice of HIV medicine is urgently needed to maintain and extend the advances in HIV care outcomes of the past decade.

Adolescent↗
PubMed2002

Molecular genetic delineation of a deletion of chromosome 13q12-->q13 in a patient with autism and auditory processing deficits.

In a sporadic case of autism and language deficit due to auditory processing defects, molecular genetic studies revealed that a chromosomal deletion occurred in the 13q12-->q13 region. No chromosome abnormalities were detected in the parents. We determined that the deletion occurred on the paternally derived chromosome 13. There are two previous reports of chromosome 13 abnormalities in patients with autism. The deletion in the subject described in this paper maps between the two chromosome 13 linkage peaks described by Bradford et al. (2001) in studies of subjects with autism and language deficits. The 9-Mb region deleted in the patient described here contains at least four genes that are expressed in brain and that play a role in brain development. They are NBEA, MAB21L1, DCAMKL1 and MADH9. These genes therefore represent candidate genes for autism and specific language deficits.

Autistic Disorder↗
PubMed2001

Recent patterns and mechanisms of carbon exchange by terrestrial ecosystems.

Knowledge of carbon exchange between the atmosphere, land and the oceans is important, given that the terrestrial and marine environments are currently absorbing about half of the carbon dioxide that is emitted by fossil-fuel combustion. This carbon uptake is therefore limiting the extent of atmospheric and climatic change, but its long-term nature remains uncertain. Here we provide an overview of the current state of knowledge of global and regional patterns of carbon exchange by terrestrial ecosystems. Atmospheric carbon dioxide and oxygen data confirm that the terrestrial biosphere was largely neutral with respect to net carbon exchange during the 1980s, but became a net carbon sink in the 1990s. This recent sink can be largely attributed to northern extratropical areas, and is roughly split between North America and Eurasia. Tropical land areas, however, were approximately in balance with respect to carbon exchange, implying a carbon sink that offset emissions due to tropical deforestation. The evolution of the terrestrial carbon sink is largely the result of changes in land use over time, such as regrowth on abandoned agricultural land and fire prevention, in addition to responses to environmental changes, such as longer growing seasons, and fertilization by carbon dioxide and nitrogen. Nevertheless, there remain considerable uncertainties as to the magnitude of the sink in different regions and the contribution of different processes.

Journal Article↗
PubMed2001

Water-based nanoparticulate polymeric system for protein delivery.

This article features a new production technology for nanoparticles comprised of multicomponent polymeric complexes that are candidates for delivery vehicles of biological molecules such as proteins and drugs. Biocompatible and mostly natural polymers are fabricated into thermodynamically stable nanoparticles insoluble in water and buffered media, in the absence of organic solvents, using two types of processing: batch and continuous. Careful choice of construction materials and the superposition of several interacting principles during their production allow for the customization of the physicochemical properties of the structures. Detailed experiments in batch and continuous systems allowed time-dependent stoichiometric characterization of the production process and an understanding of fundamental assembly principles of such supramolecular structures. Continuous-flow production is shown to provide more consistent data in terms of product quality and consistency, with further possibility of process development and commercialization. The development of nanoparticles using the described methodology is expected to lead to a flexible nanoparticle drug delivery system for medical applications, which has particular bearing to the slow release of drugs, antigens (for vaccine design), and genes (for gene therapy). Several chemistries of particles are presented.

Animals↗
PubMed2001

Chagas' disease.

Explore the source record for details and available documents.

Animals↗
PubMed2001

Consistent land- and atmosphere-based U.S. carbon sink estimates.

For the period 1980-89, we estimate a carbon sink in the coterminous United States between 0.30 and 0.58 petagrams of carbon per year (petagrams of carbon = 10(15) grams of carbon). The net carbon flux from the atmosphere to the land was higher, 0.37 to 0.71 petagrams of carbon per year, because a net flux of 0.07 to 0.13 petagrams of carbon per year was exported by rivers and commerce and returned to the atmosphere elsewhere. These land-based estimates are larger than those from previous studies (0.08 to 0.35 petagrams of carbon per year) because of the inclusion of additional processes and revised estimates of some component fluxes. Although component estimates are uncertain, about one-half of the total is outside the forest sector. We also estimated the sink using atmospheric models and the atmospheric concentration of carbon dioxide (the tracer-transport inversion method). The range of results from the atmosphere-based inversions contains the land-based estimates. Atmosphere- and land-based estimates are thus consistent, within the large ranges of uncertainty for both methods. Atmosphere-based results for 1980-89 are similar to those for 1985-89 and 1990-94, indicating a relatively stable U.S. sink throughout the period.

Agriculture↗
PubMed2001

Metabolites of dietary 1,8-cineole in the male koala (Phascolarctos cinereus).

The in vivo metabolic fate of 1,8-cineole was investigated in six male koalas. Koalas were fed ad lib a diet of Eucalyptus cephalocarpa leaf with a 1,8-cineole concentration of 2.53+/-0.70% dry mass of leaf, corresponding to a 1,8-cineole intake of 2.4+/-1.1 mmol/kg (3.1+/-1.3 g). Urine and faeces were collected for 24 h and metabolites identified by GC-MS and LC-MS. Metabolites were quantified before and after hydrolysis with beta-glucuronidase to give free and total levels, respectively. Fractional recovery of ingested 1,8-cineole was 1.3+/-0.4 and 1.4+/-0.4 (mean+/-S.D.) for free and total measurements, respectively. Seven metabolites were identified and quantified: 9- and 7-hydroxycineole, 9- and 7-cineolic acid, 7-hydroxy-9-cineolic acid, 9-hydroxy-7-cineolic acid and 7,9-dicineolic acid. The hydroxycineolic acids dominated the metabolite profile (85%). 7,9-Dicineolic acid, a novel metabolite of 1,8-cineole, accounted for almost 10% of the recovered dose making it the second most abundant metabolite after 7-hydroxy-9-cineolic acid (77%). Together, the less oxidised metabolites, the hydroxycineoles and cineolic acid, accounted for only 5% of the cineole consumed. Significant conjugation only occurred with four minor, less oxidised, alcohol and carboxylic acid metabolites. We have shown that the koala detoxifies and eliminates 1,8-cineole primarily by extensive oxidation without utilising conjugation pathways.

Animals↗
PubMed2001

Elevated blood lead levels in urban moonshine drinkers.

STUDY OBJECTIVE: During a study of problem drinking, we found that surprisingly large numbers of emergency department patients reported moonshine consumption. Because of sporadic reports of moonshine-associated lead toxicity in rural areas, we suspected that urban ED patients might have previously unidentified elevated blood lead levels caused by moonshine consumption. We initiated an active screening program to identify patients with moonshine-associated elevated blood lead levels. METHODS: We performed a prospective case-finding effort at a large urban ED in Atlanta, GA, screening all patients admitted to the ED for a 6-month period during times when study personnel were available. Patients reporting moonshine consumption within the preceding 5 years were asked to participate. After written informed consent, subjects completed a structured interview administered by one of the investigators, and blood was obtained for determination of a whole blood lead level. We recorded the numbers of patients reporting moonshine consumption, time of most recent consumption, other potential sources of lead exposures, and whole blood lead levels. RESULTS: Of 49 patients reporting consumption of moonshine within the past 5 years, 25 (51%) of 49 had elevated blood lead levels (>15 microg/dL), with 15 (31%) of 49 having extremely elevated blood lead levels (>50 microg/dL). Recent moonshine consumption (within the past month) was reported by 38 (78%) of 49 patients. Of these 38 recent consumers, 23 (61%) had elevated lead levels compared with only 2 (18%) of 11 of those reporting more remote consumption (risk difference 42%; 95% confidence interval 15% to 70%). CONCLUSION: A high percentage of patients who reported moonshine consumption had elevated blood lead levels. Emergency physicians should consider screening to determine the prevalence of moonshine consumption in their practice settings, as well as the possibility of lead intoxication among patients with suggestive symptoms. All patients reporting moonshine consumption within the past 5 years should be tested for lead exposure.

Adult↗
PubMed2001

There are stable individual differences in performance variability, both from moment to moment and from day to day.

Individual differences in decision speed have been regarded as direct reflections of a "primitive" functional neurophysiological characteristic, which affects performance on all cognitive tasks and so may be regarded as the "biological basis of intelligence", or of age-related changes in mental abilities. More detailed analyses show that variability within an experimental session (WSV) is a stable individual difference characteristic and that mean choice reaction times (CRTs) are gross summary statistics that reflect variability, rather than maximum speed of performance. A total of 98 people aged from 60 to 80 years completed 36 weekly sessions on six different letter categorization tasks. After effects of practice and of circadian variability had been eliminated, individuals with lower scores on the Cattell Culture Fair intelligence test had slower CRTs and greater WSV on all tasks. A simulation study showed that the greater WSVs of low Cattell scorers led directly to the significantly greater variability of their mean CRTs from session to session. However because CRTs on tasks co-varied from session to session it was apparent that, besides being affected by WSV, individuals' between-session variabilities (BSVs) also vary because of state changes that affect their performance from day to day. It seems that both variability in performance from trial to trial during a session and variability in average performance from day to day are correlated, stable, individual difference characteristics that vary inversely with intelligence test performance. Methodological consequences of these results for interpretations of age-related cognitive changes, for variability between as well as within individuals, for individual differences in decision speed, and for circadian variability in performance are discussed.

Aged↗
PubMed2001

Results of immediate breast reconstruction after skin-sparing mastectomy.

Skin sparing mastectomy (SSM) removes the breast, nipple-areolar complex, previous biopsy incisions, and skin overlying superficial tumors. Preservation of the native skin envelope facilitates immediate breast reconstruction. The procedure has been adopted for the treatment of breast cancer. All cases of SSM and immediate breast reconstruction performed by the senior author (G.W.C.) from January 1, 1993, through December 12, 1997, were reviewed. Patient demographics, cancer staging, treatment, types of surgery performed, and postoperative outcomes were examined. Aesthetic outcomes were measured using four 3-point subscales. A total of 100 patients underwent 118 SSMs during the study period. The American Joint Committee on Cancer staging was as follows: stage 0, 27 patients; stage I, 25 patients; stage II, 39 patients; stage III, 7 patients; stage IV, 3 patients; recurrent, 2 patients; and cystosarcoma phylloides, 1 patient. The mean follow-up was 42.7 months. Local recurrence occurred in 2 patients (2.7%). Reconstructive methods included the transverse rectus abdominis musculocutaneous flap (N = 82; pedicled, 73; free, 9), the latissimus flap (N = 18), and tissue expansion (N = 20). Two patients underwent contralateral delayed reconstruction. The aesthetic results achievable with the three methods were similar. The failure rate was higher for expander reconstruction (10%) than those observed for transverse rectus abdominis musculocutaneous (4.9%) and latissimus (5.6%) flaps. SSM can be used in the treatment of invasive breast cancer without compromising local control. The aesthetic results of the three methods were similar, but tissue expander reconstruction had a higher failure rate.

Adult↗
PubMed2001

Breast cancer after augmentation mammaplasty: treatment by skin-sparing mastectomy and immediate reconstruction.

Breast conservation has been associated with poor cosmetic outcome when used to treat breast cancer in patients who have undergone prior augmentation mammaplasty. Radiation therapy of the augmented breast can increase breast fibrosis and capsular contraction. Skin-sparing mastectomy and immediate reconstruction are examined as an alternative treatment.Six patients with prior breast augmentation were treated for breast cancer by skin-sparing mastectomy and immediate reconstruction. One patient underwent a contralateral prophylactic skin-sparing mastectomy. Silicone gel implants had been placed in the submuscular location in five patients and in the subglandular position in one patient a mean of 10.2 years (range, 6 to 20 years) before breast cancer diagnosis. The mean patient age was 41.3 years (range, 33 to 56 years). Four independent judges reviewed postoperative photographs to grade the aesthetic results in comparison with the opposite native or reconstructed breast. The American Joint Committee on Cancer staging was stage 0 in one patient, stage I for four patients, and stage II for one patient. Five of the six patients presented with a palpable breast mass. Latissimus dorsi flap reconstruction was performed in four patients (bilaterally in one) and a transverse rectus abdominis muscle (TRAM) flap was used in two patients. Three patients were treated by skin-sparing mastectomy with preservation of the breast implant (two patients with latissimus flaps, and one patient with a TRAM flap). The tumor location necessitated the removal of implants in two patients (one patient with a latissimus flap and one with a TRAM. A saline implant was placed under the latissimus flap after gel implant removal. The patient who underwent bilateral skin-sparing mastectomies desired explantation and placement of saline implants. No remedial surgery was performed on the opposite breast to achieve symmetry. Complications occurred in two patients at the latissimus dorsi donor site (seroma in one patient, and seroma and infection in one). Five patients underwent complete nipple reconstructions. The mean duration of follow-up was 33.6 months (range, 15.5 to 70.3 months), and there were no recurrences of breast cancer. The aesthetic results were judged to be good to excellent in all cases.Skin-sparing mastectomy and immediate reconstruction can be used in patients with prior breast augmentation, with good to excellent cosmetic results. Depending on the tumor and implant location, the implant may be preserved without compromising local control.

Adult↗