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PubMed2004

Multi-objective analysis of ground-level ozone concentration control.

To develop sound air quality plans, regional authorities should have instruments that link the complex behaviour of pollutants both in time and space with costs of emission reduction. The problem is particularly important for ground level ozone which forms kilometres away, hours later from the emission of its precursors. To approach this problem, a method (1) to identify local pollutant-precursor models on the basis of results from a large photochemical model (CALGRID), (2) to integrate them in a multi-objective mathematical program, together with an estimate of the emission reduction costs, is suggested. The method has been used to assess action priorities in Lombardy (Northern Italy). This area, characterised by a complex terrain, high urban and industrial emissions and a dense road network is often affected by severe photochemical pollution episodes during summer.

Air Pollution↗
PubMed2000

Decline in osteocyte lacunar density in human cortical bone is associated with accumulation of microcracks with age.

Despite osteocytes' ideal position to sense the local environment and thereby influence bone remodeling, the function of osteocytes in bone remains controversial. In this study, histomorphometric examination of male and female femoral middiaphyseal cortical bone was conducted to determine if bone's remodeling response, indicated by tissue porosity and accumulation of damage, is associated with osteocyte lacunar density (number of osteocyte lacunae per bone area). The results support the sensory role of the osteocyte network as the decline in osteocyte lacunar density in human cortical bone is associated with the accumulation of microcracks and increase in porosity with age. Porosity and microcrack density increased exponentially with a decline in osteocyte lacunar density indicating that a certain minimum number of osteocytes is essential for an "operational" network. No gender-related differences were found in the relationship of osteocyte lacunar density to age, porosity, or microcrack density. The coefficient of variation of osteocyte lacunar density increased linearly with age, indicating that aging bone tissue is characterized by increased heterogeneity in the spatial organization of osteocytes. Osteocyte lacunar density, porosity, and microcrack density exhibited the same exponential probability density distribution in the donor population, indicating their regulation by similar biological phenomena.

Adolescent↗
PubMed2002

Evaluating an interpolation approach for modelling spatial variability in pest development.

Air temperatures estimated by partial thin plate spline interpolation, or from the 'nearest station' (Voronoi polygon method), were used to model the phenology of three pests of horticultural crops throughout England and Wales. Temperatures for a particularly hot (1976) and a particularly cold (1986) year were interpolated to a grid resolution of 1 km. Estimates were made of the timing of spring emergence (Cecidophyopsis ribis (Westwood)), the maximum number of generations completed during the summer (Plutella xylostella (Linnaeus)) and the numbers of days when mating was possible (Merodon equestris (Fabricius)). The relative accuracy of the two temperature estimation methods was compared using jack-knife cross-validation. For C. ribis and P. xylostella, modelling with interpolated temperature input data was more accurate than using data from the 'nearest station'. Of the three phenology models used, the one that relied on an activity threshold (M. equestris) was the most sensitive to both types of input data. Spatial variability in the activity of M. equestrisadults was investigated in the two main areas (south-west peninsula and Lincolnshire) where its host crop (Narcissus) is grown. Modelling at cruder scales (up to 25*25 km) masked local variation, but the degree to which this was important varied from region to region and over time, as did the geography of the variability itself. The results indicate that interpolated data, computed to a resolution of 1 km using the UK synoptic network, have the potential for wider use within agricultural decision support systems for horticultural crops.

Animals↗
PubMed2000

Progress in malaria control in China.

PURPOSE: To summarize the main achievements of the control of malaria in the People's Republic of China. DATA SOURCES: The data are from national case reporting system (1955-1998), and bibliographic reviews of textbooks and review articles. STUDY SELECTION: Successes in control and research of malaria were identified and selected to address the stated purpose. DATA EXTRACTION: In the past 50 years, large-scale malaria control activities were conducted in the country, relying on primary health care networks and community participation. The control of malaria was implemented according to the time- and locality-oriented approaches. As a result, remarkable success has been achieved. By the end of 1998, there were 31.3 thousand malaria cases in China, with a morbidity of 0.25 per ten thousand, which dropped by 99% in comparison with that in the 1950s. RESULTS: Most of the original hyper-endemic areas became meso- or hypo-endemic and for most of the previously meso- or hypo-endemic areas, the disease became sporadic. Malaria distribution and epidemic pattern also demonstrated great changes. CONCLUSIONS: Malaria control in China has been considerably successful in the past 50 years, which coincides with the target of the World Health Organization's "Health for all by the year 2000".

China↗
PubMedDate not supplied

Preoperative therapy with concurrent paclitaxel/carboplatin/infusional 5-FU and radiation therapy in locoregional esophageal cancer: final results of a Minnie Pearl Cancer Research Network phase II trial.

PURPOSE: This phase II study was designed to determine the feasibility, toxicity, and therapeutic efficacy of a novel outpatient combined-modality preoperative regimen in patients with localized esophageal cancer. PATIENTS AND METHODS: One hundred twenty-nine eligible patients with previously untreated, potentially resectable, clinical stage I-III carcinoma of the esophagus were treated between July 1995 and July 1999. Combined-modality treatment included: paclitaxel, 200 mg/m2, 1-hour i.v. infusion, days 1 and 22; carboplatin, an area under the concentration time curve 6.0 i.v., days 1 and 22; 5-fluorouracil, 225 mg/m2/day, continuous i.v. infusion, days 1-42; and radiation therapy, 45 Gy, 1.8-Gy single daily fractions 5 days weekly, beginning day 1. All patients underwent surgical resection 4-8 weeks after completion of the preoperative therapy. RESULTS: One hundred twenty-three patients (95%) completed preoperative therapy, 105 patients (81%) underwent attempted resection, and 96 patients (74%) had definitive resection. A pathological complete response was achieved in 47 of 123 evaluable patients (38%); an additional 30 patients (24%) had only microscopic residual tumor. With a median follow-up of 45 months, the median survival is 22 months (95% CI = 15-32 months), with actuarial 1-, 2-, and 3-year survivals of 71%, 47%, and 41%, respectively. The most frequent grade 3/4 toxicities of the neoadjuvant program were leukopenia (73%) and esophagitis (43%). Although 73 patients (57%) required brief hospitalizations during preoperative therapy, there were no treatment-related deaths, and 94% of patients remained candidates for resection after the completion of treatment. Six patients (6%) died after surgery. CONCLUSIONS: This novel combined-modality regimen is highly active in the treatment of locoregional esophageal cancer, producing an actuarial 3-year survival of 41%. Although this preoperative regimen produced moderate acute toxicity, there were no treatment-related deaths and the large majority of patients were able to undergo subsequent esophageal resection. These results, obtained in a community-based setting and involving multiple surgeons, radiation oncologists, and medical oncologists, compare favorably with those of previous single-center and multicenter results. Further evaluation of novel combined-modality programs is warranted, as is the incorporation of epidermal growth factor receptor antagonists or other targeted agents.

Adenocarcinoma↗
PubMed2001

Knowledgeable, consistent, competent care: meeting the challenges of delivering quality cancer care in remote northern communities.

The Northwestern Ontario Regional Cancer Centre (NWORCC) has created outreach services that provide chemotherapy and supportive care to clients in thirteen small, remote communities. Located 100-600 km from the NWORCC, these satellite oncology services are staffed by local physicians, specially prepared nurses and support staff. The present paper reports selected findings from an evaluation of the service, based on two rounds of site visits, interviews and surveys of providers and clients. Although the consensus was that quality care was being delivered, local hospitals and other organizations had to address a variety of challenges. Those discussed in the paper include: maintaining provider competency, strengthening supportive care networks, and adjusting staffing and other resources to meet increased demands for care.

Cancer Care Facilities↗
PubMed1996

Prediction of outcome in critically ill patients using artificial neural network synthesised by genetic algorithm.

BACKGROUND: Decisions about which patients to admit to intensive care and how long to keep them there are difficult. A flexible computer-based mathematical model which is sensitive to the complexity of intensive care medicine, and which accurately models prognosis, seems highly desirable. METHODS: We have created, optimised by genetic algorithms, trained, and evaluated the performance of an artificial neural network (ANN) in the clinical setting of systemic inflammatory response syndrome and haemodynamic shock. 258 patients were selected from an intensive care database of 4484 patients at a London teaching hospital and randomised to a network training set (168) and a test set (90). The outcome evaluated was death during that hospital admission and the performance of the neural net was compared (by receiver operating characteristic [ROC] curves and by Brier scores) with that of a logistic regression model. FINDINGS: Artificial neural network performance increased with successive generations; the best-performing ANN was created after 7 generations and predicted outcome more accurately than the logistic regression model (ROC curve area 0.863 vs 0.753). INTERPRETATION: In this study, ANNs have lent themselves particularly well to modelling a complex clinical situation; we suggest that this relates to their inherently flexible nature which accommodates interactions between the clinical input fields. In addition, we have demonstrated the value of a second computational technique (genetic algorithms) in "tuning" ANN performance. These techniques can potentially be implemented in individual intensive care units; the outcome models which they will generate will be sensitive to local practice. Analysis of such accurate clinical outcome models may empower clinicians with a hitherto unappreciated degree of insight into those elements of their clinical practice which are most relevant to their patients' outcome.

Adult↗
PubMed1994

Effects of steroidal and non steroidal aromatase inhibitors on sexual behavior and aromatase-immunoreactive cells and fibers in the quail brain.

Castrated quail were treated with Silastic implants filled with testosterone (T) in association with injections of the aromatase inhibitors, R76713 (racemic vorozole; 1 mg/kg twice a day) or 4-hydroxyandrostenedione (OHA; 5 mg/bird twice a day). Control birds received no treatment (CX group) or were implanted with T capsules only (CX + T group). Both R76713 and OHA strongly inhibited the T-activated male copulatory behavior. This inhibition had the same magnitude in both groups. The growth of the cloacal gland, a strictly androgen-dependent process was not affected by these compounds. The treatments significantly affected the number of aromatase-immunoreactive (ARO-ir) cells in each of the six brain areas that were studied: the anterior and posterior parts of the sexually dimorphic medial preoptic nucleus (POM), the septal region, the bed nucleus of the stria terminalis (BNST) and the anterior and posterior parts of the tuber. This number was significantly increased in all areas by T. In agreement with our previous study, R76713 significantly inhibited this effect of T in the tuberal hypothalamus but not in the anterior POM nor in the BNST. By contrast the effect of T on the number of ARO-ir cells was completely blocked by OHA in all brain nuclei. The two inhibitors had statistically different effects in all brain regions. Like in a previous study, R76713 increased the intensity of the staining of all ARO-ir cells. This effect took several days to develop suggesting a progressive build-up of the enzyme concentration. This was also suggested by the fact that a rebound in aromatase activity was observed 16 to 24 h after a single injection of R76713. The increased immunoreactivity was not observed in OHA-treated birds. The denser immunoreactivity in R76713-treated birds and the better tissue preservation due to the aldehyde fixative that had been used provided here a clearer picture of the cellular and subcellular localization of ARO-ir material. This allowed to identify new groups of immunoreactive cells, namely in the nucleus accumbens, in the area of the paleostriatum ventrale, in the nucleus taeniae, in the medial and caudal hypothalamus and in the medial part of the mesencephalon and of the pons. Most of the immunoreactive material was located in perikarya but some of these cells were also surrounded by dense networks of ARO-ir fibers often associated with immunopositive punctate structures.(ABSTRACT TRUNCATED AT 400 WORDS)

Androstenedione↗
PubMed1989

Neuropeptide Y-like immunoreactivity in the brain stem respiratory nuclei of the cat.

The distribution of fibres and cell bodies containing neuropeptide Y-like immunoreactivity in respiratory nuclei of the brain stem was studied using an indirect immunoperoxidase technique. In order to visualize immunoreactive perikarya, intraventricular or intratissue injections of colchicine were carried out. The richest cluster of immunoreactive perikarya was localized in the Bötzinger complex, whereas in the nuclei ambiguus, retroambiguus, parabrachialis medialis and Kölliker-Fuse area, a moderate density of cell bodies was observed. The ventrolateral subnucleus of the nucleus tractus solitarii had the lowest number of immunoreactive neurons. Neuropeptide Y-like immunoreactive fibres were abundant in the Kölliker-Fuse area, and scarce in the nuclei ambiguus, parabrachialis medialis and Kölliker-Fuse area. A moderate network of immunoreactive fibres was observed in the nuclei retroambiguus and the ventrolateral subnucleus of the nucleus tractus solitarii. The presence of neuropeptide Y-like immunoreactive areas suggests a role for this peptide in the control of respiratory mechanisms. Alternatively such a cluster of cell bodies and fibre networks might be also related with neighbouring cardiovascular control areas.

Animals↗
PubMed2005

Menkes protein localization in rat parotid acinar cells.

The aim was to study the subcellular localization of the Menkes protein (MNK; ATP7A) in the rat parotid acinar cell. MNK protein is a copper transporting P-type ATPase whose absence or dysfunction causes a fatal neurodegenerative disorder, MNK disease. Rat parotid glands were fixed and low-temperature embedded in Lowicryl K4M resin, and ultrathin sections were prepared for immunocytochemical analysis. Immunolocalization of MNK was demonstrated mainly over the trans Golgi network (TGN) area. Immature and mature secretory granules were also labelled, indicating that MNK protein could be involved here in copper secretion from acinar cells into saliva, consistent with a proposed cariostatic role for copper.

Adenosine Triphosphatases↗
PubMed2001

Molecular determinants of ovarian cancer plasticity.

During development, the formation and remodeling of primary vascular networks occurs by vasculogenesis and angiogenesis. Recently, the term "vasculogenic mimicry" has been used by our laboratory and collaborators to reflect the embryonic-like ability of aggressive, but not nonaggressive, melanoma tumor cells to form a pattern of matrix-rich networks (containing channels) surrounding spheroids of tumor cells in three-dimensional culture, concomitant with their expression of vascular cell markers. Ovarian cancer is usually diagnosed as advanced stage disease in most patients when widespread metastases have already been established within the peritoneal cavity. In this study, we explored whether invasive ovarian carcinoma cells could engage in molecular vasculogenic mimicry reflected by their plasticity, compared with their normal cell counterparts. The data revealed that the invasive ovarian cancer cells, but not normal ovarian surface epithelial cells, formed patterned networks containing solid and hollow matrix channels when grown in three-dimensional cultures containing Matrigel or type I collagen, in the absence of endothelial cells or fibroblasts. Immunohistochemical analysis showed that matrix metalloproteinases (MMP)-1, -2, and -9, and MT1-MMP were discretely localized to these networks, and the formation of the networks was inhibited by treatment with MMP inhibitors. Furthermore, the RNase protection assay revealed the expression of multiple vascular cell-associated markers by the invasive ovarian cancer cells. In patient tumor sections from high-stage, high-grade ovarian cancers, 7 to 10% of channels containing red blood cells were lined by tumor cells. By comparison, all vascular areas in benign tumors and low-stage cancers were endothelial lined. These results may offer new insights and molecular markers for consideration in ovarian cancer diagnosis and treatment strategies based on molecular vascular mimicry by aggressive tumor cells.

Female↗
PubMed2002

Evaluating the roles of thrombin and calcium in the activation of coagulation factor XIII using H/D exchange and MALDI-TOF MS.

Factor XIII catalyzes the formation of isopeptide bonds between noncovalently associated fibrin monomers in the final stages of the blood coagulation cascade. This results in a rigid, covalently linked network that is much more resistant to proteolytic degradation. Calcium ion is critical to this process, and its continued presence after activation aids in maintenance of Factor XIII activity. Hydrogen/deuterium exchange experiments were conducted on recombinant Factor XIII a(2) using matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The method revealed changes in the structure of Factor XIII a(2) localized to different areas of the protein that were related to the manner in which the enzyme was activated and the calcium environment in which it was maintained. A possible substrate recognition region in the catalytic core (220-230) shows an increase in deuteration upon activation. The degree of deuteration varies depending on the calcium environment in which the active enzyme is maintained. A portion of the beta-sandwich domain (98-104) exhibits a decrease in deuteration upon activation by exposure to calcium alone. A third change occurs in the beta-barrel 1 domain of the protein, a portion of which (526-546) shows a decrease in deuteration upon activation by calcium exposure, but almost none at all when the enzyme is activated by thrombin. The pattern of observed changes reveals individual contributions of calcium and thrombin to activating the enzyme toward substrate binding and exposure of the active site.

Amino Acid Sequence↗
PubMed2007

Decoding the neural substrates of reward-related decision making with functional MRI.

Although previous studies have implicated a diverse set of brain regions in reward-related decision making, it is not yet known which of these regions contain information that directly reflects a decision. Here, we measured brain activity using functional MRI in a group of subjects while they performed a simple reward-based decision-making task: probabilistic reversal-learning. We recorded brain activity from nine distinct regions of interest previously implicated in decision making and separated out local spatially distributed signals in each region from global differences in signal. Using a multivariate analysis approach, we determined the extent to which global and local signals could be used to decode subjects' subsequent behavioral choice, based on their brain activity on the preceding trial. We found that subjects' decisions could be decoded to a high level of accuracy on the basis of both local and global signals even before they were required to make a choice, and even before they knew which physical action would be required. Furthermore, the combined signals from three specific brain areas (anterior cingulate cortex, medial prefrontal cortex, and ventral striatum) were found to provide all of the information sufficient to decode subjects' decisions out of all of the regions we studied. These findings implicate a specific network of regions in encoding information relevant to subsequent behavioral choice.

Adult↗
PubMed2006

Study of patients with ocular hypertension with scanning laser polarimetry and short-wavelength automatic perimetry.

AIMS: To compare and correlate retinal nerve fiber layer (RNFL) measurements obtained by scanning laser polarimetry (SLP) with defects detected by short-wavelength automatic perimetry (SWAP) in eyes with ocular hypertension (OHT). METHODS: SLP and SWAP were performed in 96 eyes of 48 consecutive patients with OHT. RESULTS: Twenty-five eyes (26%) had SWAP visual field defects. Twenty-seven eyes (28.1%) had abnormal RNFL evaluation defined by the GDx neural network ('number' > 29). Fourteen eyes of 10 patients (14.5%) had abnormal RNFL evaluation and SWAP visual field defects. RNFL thickness measurements were significantly reduced in eyes with abnormal SWAP. A weak but statistically significant correlation between the 'number' and pattern standard deviation (r = 0.3, p = 0.006) and the corrected pattern standard deviation (r = 0.3, p = 0.007) in SWAP was found. Areas of abnormal RNFL thickness corresponded to the localization of the SWAP visual field defects in corrected pattern deviation plots in 10 of the 14 eyes with defects in both tests. CONCLUSIONS: SWAP visual field defects frequently coexist and correspond with abnormalities of RNFL detected by SLP in eyes with OHT. In certain eyes, however, the two methods detect different glaucoma properties.

Diagnostic Techniques, Ophthalmological↗
PubMed1997

AUDIOMAT: an electronic newspaper for visually impaired people.

Electronic newspapers are now becoming available via wide-area computer networks, such as the internet. Unfortunately, the Windows-based graphical user interface of the client programs makes it difficult for visually impaired people to use such services. Furthermore, few visually impaired people have a PC. The AUDIOMAT project was designed to provide a reading system for the visually impaired, thus giving this community in the Campania region of southern Italy the opportunity to read their local newspaper. In a pilot trial, three blind subjects used the AUDIOMAT system daily for two months. Despite some minor technical problems the system performed well and a wider validation phase is now planned.

Computer Communication Networks↗
PubMed1985

The flow and dispersion of water in the vascular network of dicotyledonous leaves.

The relationships between the geometric characteristics of, the local flow rates of xylem sap in, and relative pressures in the reticulate anastomosing vascular network of dicotyledonous leaves of Populus Balsamifera L. are reported. The conducting channels of cellulosic microcapillaries are covered by sheaths of chloroplast free cells through the walls of which water withdrawn from vascular bundles percolates to reach evaporation sites. Along the mid-rib and branch generations, the population and cross-section areas of the microcapillaries decrease with distance but not in a monotonic manner. Lateral withdrawal rates from the veins were highest at the base of the leaf lamina. More than 50% of the inlet stream had dispersed out of the conduits within the first 25% of the leaf lamina area from the petiole junction. Absolute values of pressure gradients generally decreased in the apical direction along the vein.

Biological Transport↗
PubMed1999

[Informationization policies of local governments].

In line with the rapid progress in technical innovation, the wave of informationization is now reaching every aspect of Japanese society. With the explosive spread of the Internet, local governments are implementing administrative policies to facilitate the construction of information network systems which will help promote the spread of information at the local level. The Ministry of Posts and Telecommunications, the Ministry of International Trade and Industry, and other organizations of the Japanese government are also implemending a variety of measures to assist these moves on the part of local governments. A look at administrative services for local residents reveals a great need for the proliferation of information within the areas of welfare and medical care; in particular, counselling concerning nursing care and medical services in remote areas are needed. In order to realize new measures promoting informationization, however, the cooperation and understanding of local governors or mayors are essential. Because these people are very busy, short video and computer graphic presentations should be prepared in order to make the greatest impact in the least amount of time.

Computers↗
PubMedDate not supplied

The MYSound Project: building an estuary-wide monitoring network for Long Island Sound, USA.

A network of five water quality monitoring stations has been established in Long Island Sound, measuring temperature, salinity, and dissolved oxygen since 1999. The stations are located in areas of extreme water quality degradation (western Long Island Sound) as well as in pristine areas (eastern Long Island Sound). The data from these stations are collected every 15 minutes and posted to the project web site in real time as provisional data. After subsequent quality assurance procedures, the data are archived to the project File Transfer Protocol (FSP) site for downloading by the user community. The network of stations is in part supported logistically by a number of partners, including state and local agencies, schools, and non-governmental organizations. Data from the monitoring programs of some of these partners are also published to the project website providing a more comprehensive and complete picture of the status of the Sound than can be provided independently. This repository of information is used by marine educators, resource managers, scientists, and the general public, each with a different end purpose. We use the data from two of the stations to show that these high frequency time series measurements can be used to complement and enhance other monitoring programs within the Sound, documenting in greater detail the occurrence and duration of hypoxic events.

Automation↗