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1.
J Craniomaxillofac Surg ; 52(6): 671-691, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38644092

ABSTRACT

The systematic review aims to answer the PICOS question: "Are the autologous platelet concentrates (APCs) an effective strategy in prevention and/or treatment of patients at risk of/affected by medication-related osteonecrosis of the jaws (MRONJ)?". A literature search was conducted via PubMed, MEDLINE, EMBASE, and CINAHL (January 2006 - September 2023). 30 articles were included, evaluating preventive (n = 8*) and treatment strategies (n = 23*). The risk of bias and quality of studies were assessed utilising ROB-2, ROBIN-1 and GRADE criteria. Meta-analysis was undertaken for eligible studies. The application of APCs demonstrated a statistically significant effectiveness in prevention of MRONJ in 86.13% (p < 0.001) but failed to achieve the same level of certainty in treatment of established MRONJ in 83.4% (p = 0.08). High levels of bias were identified; thus, the results should be interpreted with caution. More high quality prospective randomised controlled trials are needed to further evaluate the effectiveness of APCs in management of MRONJ.


Subject(s)
Bisphosphonate-Associated Osteonecrosis of the Jaw , Humans , Bisphosphonate-Associated Osteonecrosis of the Jaw/prevention & control , Bisphosphonate-Associated Osteonecrosis of the Jaw/therapy , Platelet-Rich Plasma , Blood Platelets , Platelet Transfusion , Treatment Outcome
2.
Glob Chang Biol ; 30(1): e17086, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38273496

ABSTRACT

Plant communities are being exposed to changing environmental conditions all around the globe, leading to alterations in plant diversity, community composition, and ecosystem functioning. For herbaceous understorey communities in temperate forests, responses to global change are postulated to be complex, due to the presence of a tree layer that modulates understorey responses to external pressures such as climate change and changes in atmospheric nitrogen deposition rates. Multiple investigative approaches have been put forward as tools to detect, quantify and predict understorey responses to these global-change drivers, including, among others, distributed resurvey studies and manipulative experiments. These investigative approaches are generally designed and reported upon in isolation, while integration across investigative approaches is rarely considered. In this study, we integrate three investigative approaches (two complementary resurvey approaches and one experimental approach) to investigate how climate warming and changes in nitrogen deposition affect the functional composition of the understorey and how functional responses in the understorey are modulated by canopy disturbance, that is, changes in overstorey canopy openness over time. Our resurvey data reveal that most changes in understorey functional characteristics represent responses to changes in canopy openness with shifts in macroclimate temperature and aerial nitrogen deposition playing secondary roles. Contrary to expectations, we found little evidence that these drivers interact. In addition, experimental findings deviated from the observational findings, suggesting that the forces driving understorey change at the regional scale differ from those driving change at the forest floor (i.e., the experimental treatments). Our study demonstrates that different approaches need to be integrated to acquire a full picture of how understorey communities respond to global change.


Subject(s)
Ecosystem , Forests , Trees , Plants , Nitrogen
3.
J Chem Ecol ; 45(4): 348-355, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30788655

ABSTRACT

Aggregation of the bean flower thrips, Megalurothrips sjostedti (Trybom) (Thysanoptera: Thripidae), has been observed on cowpea, Vigna unguiculata (L.) Walp. To understand the mechanism underpinning this behavior, we studied the responses of M. sjostedti to headspace volatiles from conspecifics in a four-arm olfactometer. Both male and female M. sjostedti were attracted to male, but not to female odor. Gas chromatography/mass spectrometry (GC/MS) analyses revealed the presence of two distinct compounds in male M. sjostedti headspace, namely (R)-lavandulyl 3-methylbutanoate (major compound) and (R)-lavandulol (minor compound); by contrast, both compounds were only present in trace amounts in female headspace collections. A behavioral assay using synthetic compounds showed that male M. sjostedti was attracted to both (R)-lavandulyl 3-methylbutanoate and (R)-lavandulol, while females responded only to (R)-lavandulyl 3-methylbutanoate. This is the first report of a male-produced aggregation pheromone in the genus Megalurothrips. The bean flower thrips is the primary pest of cowpea, which is widely grown in sub-Saharan Africa. The attraction of male and female M. sjostedti to these compounds offers an opportunity to develop ecologically sustainable management methods for M. sjostedti in Africa.


Subject(s)
Sex Attractants/metabolism , Thysanoptera/metabolism , Vigna/parasitology , Acyclic Monoterpenes , Animals , Female , Gas Chromatography-Mass Spectrometry , Male , Monoterpenes/metabolism , Sexual Behavior, Animal , Thysanoptera/physiology
4.
Glob Chang Biol ; 24(4): 1722-1740, 2018 04.
Article in English | MEDLINE | ID: mdl-29271579

ABSTRACT

The contemporary state of functional traits and species richness in plant communities depends on legacy effects of past disturbances. Whether temporal responses of community properties to current environmental changes are altered by such legacies is, however, unknown. We expect global environmental changes to interact with land-use legacies given different community trajectories initiated by prior management, and subsequent responses to altered resources and conditions. We tested this expectation for species richness and functional traits using 1814 survey-resurvey plot pairs of understorey communities from 40 European temperate forest datasets, syntheses of management transitions since the year 1800, and a trait database. We also examined how plant community indicators of resources and conditions changed in response to management legacies and environmental change. Community trajectories were clearly influenced by interactions between management legacies from over 200 years ago and environmental change. Importantly, higher rates of nitrogen deposition led to increased species richness and plant height in forests managed less intensively in 1800 (i.e., high forests), and to decreases in forests with a more intensive historical management in 1800 (i.e., coppiced forests). There was evidence that these declines in community variables in formerly coppiced forests were ameliorated by increased rates of temperature change between surveys. Responses were generally apparent regardless of sites' contemporary management classifications, although sometimes the management transition itself, rather than historic or contemporary management types, better explained understorey responses. Main effects of environmental change were rare, although higher rates of precipitation change increased plant height, accompanied by increases in fertility indicator values. Analysis of indicator values suggested the importance of directly characterising resources and conditions to better understand legacy and environmental change effects. Accounting for legacies of past disturbance can reconcile contradictory literature results and appears crucial to anticipating future responses to global environmental change.


Subject(s)
Biodiversity , Plants/classification , Climate , Europe , Forests , Human Activities , Nitrogen
5.
Bioscience ; 67(1): 73-83, 2016 Dec 21.
Article in English | MEDLINE | ID: mdl-30220729

ABSTRACT

More and more ecologists have started to resurvey communities sampled in earlier decades to determine long-term shifts in community composition and infer the likely drivers of the ecological changes observed. However, to assess the relative importance of, and interactions among, multiple drivers joint analyses of resurvey data from many regions spanning large environmental gradients are needed. In this paper we illustrate how combining resurvey data from multiple regions can increase the likelihood of driver-orthogonality within the design and show that repeatedly surveying across multiple regions provides higher representativeness and comprehensiveness, allowing us to answer more completely a broader range of questions. We provide general guidelines to aid implementation of multi-region resurvey databases. In so doing, we aim to encourage resurvey database development across other community types and biomes to advance global environmental change research.

6.
Glob Chang Biol ; 21(10): 3726-37, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26212787

ABSTRACT

Global biodiversity is affected by numerous environmental drivers. Yet, the extent to which global environmental changes contribute to changes in local diversity is poorly understood. We investigated biodiversity changes in a meta-analysis of 39 resurvey studies in European temperate forests (3988 vegetation records in total, 17-75 years between the two surveys) by assessing the importance of (i) coarse-resolution (i.e., among sites) vs. fine-resolution (i.e., within sites) environmental differences and (ii) changing environmental conditions between surveys. Our results clarify the mechanisms underlying the direction and magnitude of local-scale biodiversity changes. While not detecting any net local diversity loss, we observed considerable among-site variation, partly explained by temporal changes in light availability (a local driver) and density of large herbivores (a regional driver). Furthermore, strong evidence was found that presurvey levels of nitrogen deposition determined subsequent diversity changes. We conclude that models forecasting future biodiversity changes should consider coarse-resolution environmental changes, account for differences in baseline environmental conditions and for local changes in fine-resolution environmental conditions.


Subject(s)
Air Pollution/adverse effects , Biodiversity , Climate , Forestry , Forests , Herbivory , Europe , Time Factors
7.
Health Soc Care Community ; 23(2): 190-9, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25233846

ABSTRACT

The objective of this qualitative study was to explore the concept of 'informed choice' in the context of self-directed support (SDS) for young people with disability in transition from child to adult services. SDS is a major policy initiative introduced by the Scottish government to promote personalised services by redefining the relationship between the citizen and the state regarding social care supports. Informed choice is one of the underpinning principles of the Social Care (Self-directed Support) (Scotland) Act 2013. The theoretical approach to the research study was that of critical realism and, in particular, realistic evaluation. The research design used multiple qualitative methods involving secondary analysis of archived qualitative longitudinal interview data, and primary interviews with nine individuals, representing a wide range of stakeholders in Scotland. The study developed hypotheses concerning the facilitators and barriers to informed choice for young people with disability. Factors facilitating informed choice included supportive family and professional networks, advocacy, accessible information and experiential knowledge. Barriers to informed choice were seen to be low expectations, poor collaboration between child and adult services and bureaucratic organisational cultures. SDS is entering the implementation phase of the policy cycle in Scotland and this study will inform emerging policy, practice and future research into personalisation for young people with disability in transition. In particular, the findings point to the need to involve young people with disability at an early stage in choice-making, and to foster self-advocacy skills and supportive social networks. Informed choice for young people with disability needs to be seen as a process over time involving both information and emotions and both need to be supported to ensure successful transitions.


Subject(s)
Choice Behavior , Disabled Persons/psychology , Patient Participation/methods , Social Work/organization & administration , Transition to Adult Care/organization & administration , Humans , Interviews as Topic , Longitudinal Studies , Parent-Child Relations , Parents/psychology , Patient Participation/psychology , Patient Rights , Qualitative Research , Scotland
8.
PLoS Negl Trop Dis ; 8(12): e3316, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25474027

ABSTRACT

BACKGROUND: The sand fly Phlebotomus argentipes is arguably the most important vector of leishmaniasis worldwide. As there is no vaccine against the parasites that cause leishmaniasis, disease prevention focuses on control of the insect vector. Understanding reproductive behaviour will be essential to controlling populations of P. argentipes, and developing new strategies for reducing leishmaniasis transmission. Through statistical analysis of male-female interactions, this study provides a detailed description of P. argentipes courtship, and behaviours critical to mating success are highlighted. The potential for a role of cuticular hydrocarbons in P. argentipes courtship is also investigated, by comparing chemicals extracted from the surface of male and female flies. PRINCIPAL FINDINGS: P. argentipes courtship shared many similarities with that of both Phlebotomus papatasi and the New World leishmaniasis vector Lutzomyia longipalpis. Male wing-flapping while approaching the female during courtship predicted mating success, and touching between males and females was a common and frequent occurrence. Both sexes were able to reject a potential partner. Significant differences were found in the profile of chemicals extracted from the surface of males and females. Results of GC analysis indicate that female extracts contained a number of peaks with relatively short retention times not present in males. Extracts from males had higher peaks for chemicals with relatively long retention times. CONCLUSIONS: The importance of male approach flapping suggests that production of audio signals through wing beating, or dispersal of sex pheromones, are important to mating in this species. Frequent touching as a means of communication, and the differences in the chemical profiles extracted from males and females, may also indicate a role for cuticular hydrocarbons in P. argentipes courtship. Comparing characteristics of successful and unsuccessful mates could aid in identifying the modality of signals involved in P. argentipes courtship, and their potential for use in developing new strategies for vector control.


Subject(s)
Insect Vectors/physiology , Phlebotomus/physiology , Animals , Courtship , Female , Male
10.
Proc Natl Acad Sci U S A ; 110(46): 18561-5, 2013 Nov 12.
Article in English | MEDLINE | ID: mdl-24167287

ABSTRACT

Recent global warming is acting across marine, freshwater, and terrestrial ecosystems to favor species adapted to warmer conditions and/or reduce the abundance of cold-adapted organisms (i.e., "thermophilization" of communities). Lack of community responses to increased temperature, however, has also been reported for several taxa and regions, suggesting that "climatic lags" may be frequent. Here we show that microclimatic effects brought about by forest canopy closure can buffer biotic responses to macroclimate warming, thus explaining an apparent climatic lag. Using data from 1,409 vegetation plots in European and North American temperate forests, each surveyed at least twice over an interval of 12-67 y, we document significant thermophilization of ground-layer plant communities. These changes reflect concurrent declines in species adapted to cooler conditions and increases in species adapted to warmer conditions. However, thermophilization, particularly the increase of warm-adapted species, is attenuated in forests whose canopies have become denser, probably reflecting cooler growing-season ground temperatures via increased shading. As standing stocks of trees have increased in many temperate forests in recent decades, local microclimatic effects may commonly be moderating the impacts of macroclimate warming on forest understories. Conversely, increases in harvesting woody biomass--e.g., for bioenergy--may open forest canopies and accelerate thermophilization of temperate forest biodiversity.


Subject(s)
Adaptation, Biological/physiology , Biota/physiology , Global Warming , Microclimate , Trees/physiology , Europe , North America , Population Dynamics , Seasons , Species Specificity , Temperature
11.
Trends Ecol Evol ; 26(1): 45-52, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21111511

ABSTRACT

Much ecological research focuses on changes in vegetation on spatial scales from stands to landscapes; however, capturing data on vegetation change over relevant timescales remains a challenge. Pollen analysis offers unrivalled access to data with global coverage over long timescales. Robust techniques have now been developed that enable pollen data to be converted into vegetation data in terms of individual taxa, plant communities or biomes, with the possibility of deriving from those data a range of plant attributes and ecological indicators. In this review, I discuss how coupling pollen with macrofossil, charcoal and genetic data opens up the extensive pollen databases to investigation of the drivers of vegetation change over time and also provides extensive data sets for testing hypotheses with wide ecological relevance.


Subject(s)
Biological Evolution , Ecosystem , Plants/genetics , Plants/metabolism , Time Factors , Fossils , Pollen
12.
Cancer Res ; 68(10): 3827-34, 2008 May 15.
Article in English | MEDLINE | ID: mdl-18483267

ABSTRACT

The assessment of tissue-specific pharmacodynamics is desirable in the development of tumor-targeted therapies. Plasma deoxyuridine (dUrd) levels, a measure of systemic thymidylate synthase (TS) inhibition, has limited application for studying the pharmacodynamics of novel TS inhibitors targeted to the high affinity alpha-folate receptor (FR). Here, we have evaluated the utility of [(18)F]fluorothymidine positron emission tomography ([(18)F]FLT-PET) for imaging the tissue pharmacodynamics of BGC 945, an FR-targeted antifolate TS inhibitor; the nontargeted antifolate BGC 9331 was used for comparison. TS inhibition by both drugs induced a concentration-dependent increase in [(3)H]thymidine uptake in FR-positive human epidermoid KB cells. Membrane-associated equilibrative nucleoside transporter type 1 levels increased from 55,720 +/- 6,101 to 118,700 +/- 5,193 and 130,800 +/- 10,800 per cell at 100 mug/mL of BGC 9331 and BGC 945, respectively, suggesting this as a potential mechanism of increased nucleoside uptake. In keeping with these in vitro findings, tumor [(18)F]FLT accumulation in KB xenografts increased by >/=2-fold after drug treatment with maximal levels at 1 to 4 hours and 4 to 24 hours after BGC 9331 and BGC 945 treatment, respectively. Of interest to FR targeting, BGC 9331, but not BGC 945, induced accumulation of [(18)F]FLT uptake in intestine, a proliferative and TS-responsive tissue. For both drugs, quantitative changes in tumor [(18)F]FLT uptake were associated with increased tumor dUrd levels. In conclusion, we have validated the utility of [(18)F]FLT-PET to image TS inhibition induced by antifolates and shown the tumor-specific activity of BGC 945. This imaging biomarker readout will be useful in the early clinical development of BGC 945.


Subject(s)
Biomarkers, Tumor/metabolism , Carrier Proteins/metabolism , Quinazolines/pharmacology , Receptors, Cell Surface/metabolism , Thymidylate Synthase/antagonists & inhibitors , Animals , Chemistry, Pharmaceutical/methods , Female , Fluorodeoxyglucose F18/pharmacology , Folate Receptor 1 , Folate Receptors, GPI-Anchored , Humans , Mice , Mice, Inbred BALB C , Neoplasm Transplantation , Positron-Emission Tomography/methods , Time Factors
13.
Cancer Res ; 66(17): 8558-64, 2006 Sep 01.
Article in English | MEDLINE | ID: mdl-16951168

ABSTRACT

Thymidylate synthase (EC 2.1.1.45) is a key enzyme for the de novo synthesis of DNA and as such a target for anticancer drug development. There is a need to develop noninvasive methods for assessing thymidylate synthase inhibition in tumors. The aim of this study was to assess the potential of 3'-deoxy-3'-[(18)F]fluorothymidine ([(18)F]FLT) positron emission tomography (PET) for early measurement of thymidylate synthase inhibition and to elucidate the cellular mechanisms involved. Radiation-induced fibrosarcoma-1 tumor-bearing mice were injected with a single i.p. dose of the thymidylate synthase inhibitor 5-fluorouracil (5-FU; 165 mg/kg) and imaged by [(18)F]FLT-PET at 1 to 2 hours after treatment. Deoxyuridine, thymidine kinase 1 (cytoplasmic thymidine kinase; EC2.7.1.21), and ATP levels in excised tumors were measured. Cellular assays for membrane transport were also done. There was a 1.8-fold increase in the 60-minute [(18)F]FLT tumor/heart radioactivity ratio in drug-treated mice compared with vehicle controls (P = 0.0016). Plasma and tumor deoxyuridine levels increased significantly but thymidine kinase and ATP levels were unchanged. Whole-cell assays implicated a (low level) functional role for the type-1 equilibrative nucleoside transporter (ENT). There was an increase in type-1 ENT-binding sites per cell from 49,110 in untreated cells to 73,142 (P = 0.03) in cells treated with 10 microg/mL 5-FU for 2 hours, without a change in transporter affinity (P = 0.41). We conclude that [(18)F]FLT-PET can be used to measure thymidylate synthase inhibition as early as 1 to 2 hours after treatment with 5-FU by a mechanism involving redistribution of nucleoside transporters to the plasma membrane.


Subject(s)
Cell Membrane/physiology , Nucleoside Transport Proteins/metabolism , Thymidylate Synthase/antagonists & inhibitors , Animals , Cell Line, Tumor , Cell Membrane/diagnostic imaging , Fibrosarcoma/diagnostic imaging , Fluorine Radioisotopes , Mice , Neoplasms, Radiation-Induced/diagnostic imaging , Positron-Emission Tomography
14.
Cancer Res ; 65(24): 11721-8, 2005 Dec 15.
Article in English | MEDLINE | ID: mdl-16357184

ABSTRACT

BGC 945 is a cyclopenta[g]quinazoline-based, thymidylate synthase inhibitor specifically transported into alpha-folate receptor (alpha-FR)-overexpressing tumors. Affinity of BGC 945 for the alpha-FR is 70% of the high-affinity ligand folic acid. In contrast to conventional antifolates, BGC 945 has low affinity for the widely expressed reduced-folate carrier (RFC). The K(i) for isolated thymidylate synthase is 1.2 nmol/L and the IC(50) for inhibition of the growth of alpha-FR-negative mouse L1210 or human A431 cells is approximately 7 micromol/L. In contrast, BGC 945 is highly potent in a range of alpha-FR-overexpressing human tumor cell lines (IC(50) approximately 1-300 nmol/L). Pharmacokinetic variables measured following i.v. injection of 100 mg/kg BGC 945 to KB tumor-bearing mice showed rapid plasma clearance (0.021 L/h) and tissue distribution. The terminal half-lives in plasma, liver, kidney, spleen, and tumor were 2, 0.6, 5, 21, and 28 hours, respectively. Tumor BGC 945 concentration at 24 hours was approximately 1 nmol/g tissue, at least 10-fold higher than that in plasma or normal tissues. Inhibition of thymidylate synthase in tissues leads to increased incorporation of 5-[(125)I]-iodo-2'-deoxyuridine ([(125)I]dUrd) into DNA. Forty-eight hours after injection of 100 mg/kg 6RS-BGC 945 ([(125)I]dUrd injected at 24 hours), tumor was the only tissue with incorporation above control level (6-fold). The RFC-mediated thymidylate synthase inhibitor plevitrexed also increased uptake of [(125)I]dUrd in tumor (10-fold) but, in contrast, also caused increased incorporation in other normal tissues such as spleen and small bowel (4.5- and 4.6-fold, respectively). These data suggest that BGC 945 selectively inhibits thymidylate synthase in alpha-FR-overexpressing tumors and should cause minimal toxicity to humans at therapeutic doses.


Subject(s)
Carrier Proteins/metabolism , Enzyme Inhibitors/pharmacology , Quinazolines/pharmacology , Receptors, Cell Surface/metabolism , Thymidylate Synthase/antagonists & inhibitors , Animals , Apoptosis/drug effects , Biological Transport , Cell Proliferation/drug effects , Choriocarcinoma/drug therapy , Choriocarcinoma/enzymology , Enzyme Inhibitors/pharmacokinetics , Female , Folate Receptors, GPI-Anchored , Folic Acid/metabolism , Humans , Idoxuridine/metabolism , Iodine Radioisotopes , Leukemia L1210/drug therapy , Leukemia L1210/enzymology , Lung Neoplasms/drug therapy , Lung Neoplasms/enzymology , Membrane Transport Proteins , Mice , Mice, Nude , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/enzymology , Quinazolines/pharmacokinetics , Reduced Folate Carrier Protein , Tissue Distribution , Transplantation, Heterologous , Tumor Cells, Cultured
15.
Clin Cancer Res ; 9(6): 2049-55, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12796367

ABSTRACT

PURPOSE: This dose-escalating study investigated the toxicity, pharmacokinetics, and efficacy of the novel direct-acting antifolate ZD9331, given as a 5-day i.v. infusion every 3 weeks. EXPERIMENTAL DESIGN: Forty-five patients with refractory solid malignancies received ZD9331, which was escalated from 0.125 mg/m(2)/day. RESULTS: Dose-limiting grade 4 thrombocytopenia occurred in 3 of 6 patients treated at 8 mg/m(2)/day; other drug-related toxicities, across dose levels, included skin and gastrointestinal toxicity, lethargy, and asymptomatic, reversible, elevated transaminases. The maximum plasma concentration and area under the curve increased with dose. Clearance was dose-dependent and predominantly renal. At doses >/=2.4 mg/m(2)/day, plasma 2'-deoxyuridine levels were elevated consistently indicating inhibition of thymidylate synthase. Two patients had a partial response (breast, 1 patient; ovarian, 1 patient), and 10 patients had stable disease. CONCLUSION: The maximum tolerated dose was defined as 6 mg/m(2)/day, and the toxicity profile for this regimen was considered acceptable and manageable. Administration of ZD9331 lead to elevation of 2'-deoxyuridine levels, signifying thymidylate synthase inhibition, and evidence of antitumor activity was observed.


Subject(s)
Antineoplastic Agents/adverse effects , Neoplasms/drug therapy , Quinazolines/adverse effects , Adult , Aged , Female , Humans , Infusions, Intravenous , Male , Maximum Tolerated Dose , Middle Aged , Quinazolines/administration & dosage , Quinazolines/pharmacokinetics
16.
Clin Cancer Res ; 9(4): 1313-22, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12684399

ABSTRACT

PURPOSE: ZD9331 is a novel, direct-acting antifolate cytotoxic that does not require polyglutamation for activity, and is a specific thymidylate synthase inhibitor. This Phase I trial aimed to determine the maximum tolerated dose of ZD9331, given as a 30-min i.v. infusion on days 1 and 8 of a 21-day cycle. Pharmacokinetic parameters and tumor response were also assessed. EXPERIMENTAL DESIGN: A total of 71 patients, with a range of solid malignancies and refractory to standard therapies (44% had received > or =3 prior chemotherapy regimens), were treated. The most common malignancies were colorectal cancer (35% of patients) and ovarian cancer (31%). ZD9331 was escalated from 4.8 mg/m(2)/day. RESULTS: Dose-limiting toxicity occurred at 162.5 mg/m(2) ZD9331, with grade 4 thrombocytopenia, grade 4 neutropenia lasting > or =7 days, and grade 3 nonhematologic toxicity. Plasma clearance of ZD9331 was slow and dose-dependent; however, ZD9331 pharmacokinetics were nonlinear. Pharmacodynamics of ZD9331 were determined by measurement of plasma deoxyuridine, which increased at all of the dose levels; dose-related increases in plasma deoxyuridine were significant (P = 0.003) on day 5. Stable disease was observed in 37% of patients; 23% of ovarian cancer patients had a > or =50% reduction in CA125 levels. CONCLUSIONS: The maximum tolerated dose of this schedule was 130 mg/m(2). The toxicity profile at this dose was acceptable, with 7 of 28 patients treated developing grade 3/4 neutropenia and thrombocytopenia, 2 grade 4 diarrhea, and 2 grade 3/4 rash. This schedule was convenient and demonstrated activity in extensively pretreated patients; therefore, this is the recommended dose for study in Phase II trials.


Subject(s)
Antineoplastic Agents/therapeutic use , Neoplasms/drug therapy , Quinazolines/therapeutic use , Thymidylate Synthase/antagonists & inhibitors , Adult , Aged , Antineoplastic Agents/pharmacokinetics , Area Under Curve , Dose-Response Relationship, Drug , Female , Humans , Male , Maximum Tolerated Dose , Middle Aged , Models, Chemical , Quinazolines/pharmacokinetics , Time Factors , Water/chemistry
17.
Soc Work Health Care ; 35(1-2): 605-13, 2002.
Article in English | MEDLINE | ID: mdl-12365761

ABSTRACT

Community Mental Health Teams (CMHTs) offer the opportunity to integrate social workers and health professionals to provide multi-disciplinary assessment and care. This potential for joint working is frequently not fully realised, with the various professions operating independently. Social work staff in CMHTs are reported to experience high levels of role confusion. This study of the introduction of a system of conjoint multi-disciplinary assessment in a Scottish CMHT describes the positive impact on the social work role in terms of greater involvement in front-line assessments to the CMHT and more fully integrated teamwork.


Subject(s)
Community Mental Health Services/organization & administration , Patient Care Planning , Patient Care Team , Referral and Consultation , Social Work, Psychiatric , Community Health Nursing , Humans , Interprofessional Relations , Occupational Therapy , Professional Role , Psychiatric Nursing , Psychiatry , Scotland , Urban Health Services/organization & administration
18.
Clin Cancer Res ; 8(1): 103-9, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11801545

ABSTRACT

5-Fluorouracil (5-FU) exerts cytotoxic effects through inhibition of thymidylate synthase (TS) and incorporation of metabolites into RNA. TS inhibition may be greater for infusional 5-FU, with bolus regimens more likely to cause RNA effects. Elevation of plasma 2'-deoxyuridine (dUrd) is a surrogate marker of TS inhibition. Nineteen patients were treated with continuous infusion (CI) 5-FU 300mg/m(2)/day or bolus 5-FU 425mg/m(2)/day plus leucovorin (LV) 20mg/m(2)/day days 1-5. Pretreatment (day 1) and day 2, 3, 4, 5, 8, 15, 22, and 29 plasma samples were assayed for dUrd by reverse-phase high-performance liquid chromatography. In patients treated with bolus 5-FU/LV, dUrd elevation at 24 and 48 h was 235 +/- 125 and 254 +/- 119%, respectively, falling to 138 +/- 58%, 156 +/- 89%, and 92 +/- 25% on days 8, 15, and 22, respectively. dUrd elevation with CI 5-FU was 229 +/- 86% at 24 h and 239 +/- 86, 240 +/- 98%, and 255 +/- 109% at days 15, 22, and 29, respectively. Duration of dUrd elevation was generally less than 8 days for bolus 5-FU/LV. A single dose of raltitrexed (3 mg/m(2)) gave a similar profile to this regimen. ZD9331 (130 mg/m(2), days 1 and 8) gave dUrd elevation for 14 of 21 days, with some recovery prior to day 8. Thus, both 5-FU regimens inhibit TS, and prolonged TS inhibition is achieved by CI 5-FU without significant toxicity. This suggests that the mechanism of antiproliferative toxicity from bolus 5-FU/LV is partly non-TS mediated. These results clarify underlying pharmacodynamic processes and could guide scheduling of 5-FU and TS inhibitors.


Subject(s)
Antimetabolites, Antineoplastic/therapeutic use , Colorectal Neoplasms/drug therapy , Deoxyuridine/blood , Enzyme Inhibitors/therapeutic use , Fluorouracil/therapeutic use , Quinazolines/therapeutic use , Thymidylate Synthase/antagonists & inhibitors , Biomarkers, Tumor/blood , Colorectal Neoplasms/blood , Colorectal Neoplasms/enzymology , Humans , Infusions, Intravenous , Thiophenes/therapeutic use
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