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1.
Agric Ecosyst Environ ; 184(100): 34-40, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24748698

RESUMO

Insect pollination is important for food production globally and apples are one of the major fruit crops which are reliant on this ecosystem service. It is fundamentally important that the full range of benefits of insect pollination to crop production are understood, if the costs of interventions aiming to enhance pollination are to be compared against the costs of the interventions themselves. Most previous studies have simply assessed the benefits of pollination to crop yield and ignored quality benefits and how these translate through to economic values. In the present study we examine the influence of insect pollination services on farmgate output of two important UK apple varieties; Gala and Cox. Using field experiments, we quantify the influence of insect pollination on yield and importantly quality and whether either may be limited by sub-optimal insect pollination. Using an expanded bioeconomic model we value insect pollination to UK apple production and establish the potential for improvement through pollination service management. We show that insects are essential in the production of both varieties of apple in the UK and contribute a total of £36.7 million per annum, over £6 million more than the value calculated using more conventional dependence ratio methods. Insect pollination not only affects the quantity of production but can also have marked impacts on the quality of apples, influencing size, shape and effecting their classification for market. These effects are variety specific however. Due to the influence of pollination on both yield and quality in Gala, there is potential for insect pollination services to improve UK output by up to £5.7 million per annum. Our research shows that continued pollinator decline could have serious financial implications for the apple industry but there is considerable scope through management of wild pollinators or using managed pollinator augmentation, to improve the quality of production. Furthermore, we show that it is critically important to consider all production parameters including quality, varietal differences and management costs when valuing the pollination service of any crop so investment in pollinator management can be proportional to its contribution.

2.
PLoS One ; 11(5): e0153889, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27152628

RESUMO

Insect pollination underpins apple production but the extent to which different pollinator guilds supply this service, particularly across different apple varieties, is unknown. Such information is essential if appropriate orchard management practices are to be targeted and proportional to the potential benefits pollinator species may provide. Here we use a novel combination of pollinator effectiveness assays (floral visit effectiveness), orchard field surveys (flower visitation rate) and pollinator dependence manipulations (pollinator exclusion experiments) to quantify the supply of pollination services provided by four different pollinator guilds to the production of four commercial varieties of apple. We show that not all pollinators are equally effective at pollinating apples, with hoverflies being less effective than solitary bees and bumblebees, and the relative abundance of different pollinator guilds visiting apple flowers of different varieties varies significantly. Based on this, the taxa specific economic benefits to UK apple production have been established. The contribution of insect pollinators to the economic output in all varieties was estimated to be £92.1M across the UK, with contributions varying widely across taxa: solitary bees (£51.4M), honeybees (£21.4M), bumblebees (£18.6M) and hoverflies (£0.7M). This research highlights the differences in the economic benefits of four insect pollinator guilds to four major apple varieties in the UK. This information is essential to underpin appropriate investment in pollination services management and provides a model that can be used in other entomolophilous crops to improve our understanding of crop pollination ecology.


Assuntos
Insetos/classificação , Malus , Polinização , Animais , Insetos/fisiologia , Reino Unido
3.
Clin Cancer Res ; 5(10 Suppl): 3124s-3138s, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10541353

RESUMO

The high sensitivity of pentagastrin stimulation in detecting primary or metastatic medullary thyroid cancer (MTC) suggests widespread expression of the corresponding receptor type on human MTC. Indeed, autoradiographic studies demonstrated cholecystokinin (CCK)-B/gastrin receptors not only in >90% of MTCs but in a high percentage of small cell lung cancers and potentially a variety of gastrointestinal adenocarcinomas. In a pilot study, we have demonstrated the feasibility of radiolabeled gastrin-I to target CCK-B receptor-expressing tissues in vivo in animals and patients (T. M. Behr et al., Eur. J. Nucl. Med., 25: 424-430, 1998). The aim of the present study was to systematically optimize, in a preclinical model, suitable radioligands for targeting CCK-B receptors in vivo. For this purpose, a variety of CCK/gastrin-related peptides, all having in common the COOH-terminal CCK-receptor binding tetrapeptide sequence Trp-Met-Asp-PheNH2 or derivatives thereof, were studied. They were radioiodinated by the Iodogen or Bolton-Hunter procedures. The peptides tested were members of the gastrin- or cholecystokinin families or possessed characteristics of both, which differ by the intramolecular position of a tyrosyl moiety (occurring in native or sulfated form). Their stability and affinity were studied in vitro and in vivo; their biodistribution and therapeutic efficacy were tested in nude mice bearing s.c. human MTC xenografts. Diethylene-triamine-pentaacetate derivatives of suitable peptides were synthesized, evaluated, and labeled with (111)In. All members of the CCK or gastrin family were stable in serum (with t(1/2)s of several hours at 37 degrees C); nevertheless, the stability of those peptides was highest that bore the NH2-terminal pGlu residues (e.g., big gastrin, gastrin-I, caerulein, and others) or D-amino acids. In accordance to their comparably low affinity, nonsulfated members of the CCK family showed fairly low uptake in the tumor and other CCK-B receptor-expressing tissues (e.g., the stomach). Sulfated CCK derivatives performed significantly better but additionally displayed a high uptake in normal, CCK-A receptor-expressing tissues (such as the liver/gallbladder, pancreas, and bowel). Best tumor uptake and tumor:nontumor ratios were obtained with members of the gastrin family, probably because of their selectivity and affinity for the CCK-B receptor subtype. Pilot therapy experiments in MTC bearing animals showed significant antitumor efficacy as compared with untreated controls. (111)In-Labeled diethylene-triamine-pentaacetate derivatives of minigastrin showed excellent targeting of CCK-B receptor-expressing tissues in animals and a normal human volunteer. These data suggest that CCK/gastrin analogues may be a useful new class of receptor binding peptides for diagnosis and therapy of CCK-B receptor-expressing tumors, such as MTC or small cell lung cancer. Nonsulfated gastrin derivatives may be preferable because of their CCK-B receptor selectivity, and hence, lower accretion in normal CCK-A receptor-expressing organs. Further preclinical as well as clinical studies are ongoing.


Assuntos
Gastrinas , Receptores da Colecistocinina/análise , Neoplasias da Glândula Tireoide/química , Sequência de Aminoácidos , Animais , Gastrinas/uso terapêutico , Humanos , Radioisótopos de Índio/uso terapêutico , Radioisótopos do Iodo/uso terapêutico , Marcação por Isótopo , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Receptores da Colecistocinina/metabolismo , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/terapia , Distribuição Tecidual , Células Tumorais Cultivadas
4.
J Nucl Med ; 40(6): 1029-44, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10452322

RESUMO

UNLABELLED: The high sensitivity of pentagastrin stimulation in detecting primary or metastatic medullary thyroid cancer (MTC) suggests widespread expression of the corresponding receptor type on human MTC. Indeed, autoradiographic studies have demonstrated cholecystokinin (CCK)-B/gastrin receptors not only in more than 90% of MTCs but also in a high percentage of small cell lung cancers, some ovarian cancers, astrocytomas and potentially a variety of adenocarcinomas. The aim of this study was to systematically screen and optimize, in a preclinical model and a pilot clinical study, suitable radioligands for targeting CCK-B receptors in vivo. METHODS: A variety of CCK/gastrin-related peptides, all bearing the C-terminal CCK receptor-binding tetrapeptide sequence Trp-Met-Asp-PheNH2 or derivatives thereof, were studied. They were radioiodinated by the lodogen or Bolton-Hunter procedures. The peptides were members of the gastrin or CCK families, which differ by the intramolecular position of a tyrosyl moiety. Their stability and affinity were studied in vitro and in vivo; their biodistribution and therapeutic efficacy were tested in nude mice bearing subcutaneous human MTC xenografts. Diethylenetriamine pentaacetic acid (DTPA) derivatives of suitable peptides were synthesized successfully, and their preclinical and initial clinical evaluations were performed, labeled with 111In. RESULTS: All members of the CCK or gastrin families were stable in serum (with half-lives of several hours at 37 degrees C); nevertheless, the stability of those peptides bearing N-terminal pGlu residues or D-amino acids was significantly higher. In accordance with their comparably low affinity, nonsulfated members of the CCK family showed fairly low uptake in the tumor and other CCK-B receptor-expressing tissues. Sulfated CCK derivatives performed significantly better but also displayed a comparably high uptake in normal CCK-A receptor-expressing tissues. This effect was probably due to their similar affinity for both CCK-A and CCK-B receptors. Best tumor uptake and tumor-to-nontumor ratios were obtained with members of the gastrin family because of their selectivity and affinity for the CCK-B receptor subtype. Pilot therapy experiments in MTC-bearing animals showed significant antitumor efficacy compared with untreated controls. DTPA derivatives of minigastrin were successfully developed. In a pilot clinical study, radioiodinated and 111In-labeled derivatives showed excellent targeting of physiological CCK-B receptor-expressing organs, as well as all known tumor sites. CONCLUSION: CCK/gastrin analogs may be a useful new class of receptor-binding peptides for diagnosis and therapy of CCK-B receptor-expressing tumors, such as MTC or small cell lung cancer. Nonsulfated gastrin derivatives may be preferable because of their CCK-B receptor selectivity, hence lower accretion in normal CCK-A receptor-expressing organs.


Assuntos
Carcinoma Medular/diagnóstico por imagem , Carcinoma de Células Pequenas/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Peptídeos , Radioisótopos , Receptores da Colecistocinina , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Adulto , Idoso , Sequência de Aminoácidos , Animais , Carcinoma Medular/metabolismo , Carcinoma Medular/terapia , Carcinoma de Células Pequenas/metabolismo , Carcinoma de Células Pequenas/terapia , Colecistocinina/administração & dosagem , Colecistocinina/metabolismo , Interpretação Estatística de Dados , Feminino , Gastrinas/administração & dosagem , Gastrinas/metabolismo , Humanos , Radioisótopos de Índio , Radioisótopos do Iodo , Marcação por Isótopo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/terapia , Metástase Linfática/diagnóstico por imagem , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Dados de Sequência Molecular , Metástase Neoplásica/diagnóstico por imagem , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/terapia , Peptídeos/administração & dosagem , Peptídeos/genética , Cintilografia , Receptores da Colecistocinina/análise , Receptores da Colecistocinina/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/terapia
5.
Comp Biochem Physiol B ; 96(4): 689-96, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2121413

RESUMO

1. Rainbow trout (Salmo gairdneri) beta 1----4galactosyltransferase has been characterized and its properties compared to the mammalian enzyme. 2. Transfer of galactose to lactotriaosylceramide (Lc3) was optimal in the presence of 0.12% Triton CF-54 and Mn2+, in a pH range of 6.5-7.5. 3. Apparent Km values for donor UDPgalactose and acceptor Lc3 were determined to be 40 and 38 microM, respectively. 4. Glycolipid substrate specificity was found with only Lc3 being an efficient acceptor. Transfer of galactose to glycosylceramide, efficient with mammalian enzyme, was 42-fold slower. 5. In contrast to mammalian enzyme, rainbow trout beta 1----4galactosyltransferase was found to be independent from regulation by alpha-lactalbumin by the inability of alpha-lactalbumin-Sepharose to bind the enzyme and by failure of alpha-lactalbumin to inhibit the enzyme activity.


Assuntos
Galactosiltransferases/metabolismo , Glicolipídeos/biossíntese , Lactalbumina/farmacologia , Truta/metabolismo , Animais , Sequência de Carboidratos , Detergentes/farmacologia , Galactose/metabolismo , Galactosiltransferases/antagonistas & inibidores , Complexo de Golgi/enzimologia , Concentração de Íons de Hidrogênio , Cinética , Lactalbumina/metabolismo , Lactosilceramidas/metabolismo , Fígado/enzimologia , Manganês/farmacologia , Dados de Sequência Molecular , Especificidade por Substrato , Uridina Difosfato Galactose/metabolismo
6.
J Qual Clin Pract ; 20(1): 36-41, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10821455

RESUMO

In 1989 the Australian Council on Healthcare Standards (ACHS) embarked on a programme to develop acute health care clinical indicators in conjunction with the Australian medical colleges. Through a carefully structured stepwise process this collaboration established a 'World first' in 1993 with the introduction of the first set of indicators into the ACHS Accreditation programme. The programme remains unique in the formal involvement of providers in the development process and in the scope of the clinical areas covered in acute health care. From the year 2000 there will be 18 sets (and over 200 indicators) from which health care organisations (HCOs) can choose to monitor the major services they provide. There remains no compulsion to address a specific number of indicators. The growth of the programme has been considerable with more than half of the nations' acute HCOs reporting their clinical indicator data (twice yearly) and it provides a reflection of the care given for the majority of patient separations in acute care. This reporting process allows HCOs to receive feedback on the aggregate results together with comparative peer group information for each indicator they address. In addition to numerous publications in peer reviewed journals an annual aggregate report, 'the Measurement of Care in Australian Hospitals' is published. It reports both qualitative and quantitative data on all indicator sets for the preceding year. Validity of the indicators is strengthened each year with a review process and reliability and reproducibility of the data can now be demonstrated. The clinical response to the indicators has been overwhelming and there is now documented evidence of numerous actions taken by HCOs to improve both the processes and the outcomes of patient care. The nation wide database can be expected to reflect trends in care over the next few years. The process of indicator refinement, however, will continue and it is likely that a reduction in the total number of indicators will occur with a core group of the more 'robust' indicators remaining. Further directions in indicator development are likely to be in the area of multidisciplinary care and in the assessment of longer-term outcomes. In addition to measures of the quality of care, hopefully, in time, health care providers will also take part in the establishment of measures of the appropriateness of that care.


Assuntos
Atenção à Saúde/normas , Gestão da Qualidade Total/organização & administração , Acreditação/normas , Idoso , Austrália , Coleta de Dados , Estudos de Avaliação como Assunto , Instalações de Saúde/normas , Administração de Instituições de Saúde , Humanos , Revisão dos Cuidados de Saúde por Pares , Reprodutibilidade dos Testes
7.
J Intraven Nurs ; 16(1): 50-4, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8437046

RESUMO

The intravenous therapy team at Massachusetts General Hospital studied the potential infectious risks of maintaining percutaneous inserted central catheters (PICC) for prolonged periods. Cultures of 100 PICC sites and catheters were performed on removal of the catheters, which had remained in place for 2 to 43 days. The insertion sites and/or proximal or distal segments of the catheters were found to be colonized in 11% of the patients, with distal catheter tips significantly colonized in only four patients. Nine of the patients were colonized at the insertion site. Bacteremia did not occur as a result of the extended dwell time of the catheters.


Assuntos
Bactérias/crescimento & desenvolvimento , Infecções Bacterianas/microbiologia , Cateterismo Venoso Central/efeitos adversos , Cateteres de Demora/efeitos adversos , Técnicas Bacteriológicas , Humanos
8.
Eur J Nucl Med ; 25(4): 424-30, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9553173

RESUMO

The outstanding sensitivity of pentagastrin in detecting the presence of primary, recurrent or metastatic medullary thyroid cancer (MTC) suggests widespread expression of the corresponding receptor type in human MTC. Indeed, recent autoradiographic studies have demonstrated the presence of cholecystokinin (CCK)-B (= gastrin) receptors not only in more than 90% of MTCs but also in a high percentage of small cell lung cancers, stromal ovarian cancers, astrocytomas and several other tumour types. The aim of this study was to evaluate whether radiolabelled gastrin may be suitable for targeting CCK-B receptor-expressing tumours in vivo. For this purpose, the biodistribution of the radioiodinated human heptadecapeptide gastrin-I was studied in nude mice bearing subcutaneous xenografts of the human MTC cell line, TT. Initial therapy experiments were undertaken. Finally, the biodistribution of iodine-131- labelled gastrin-I was studied in a patient with metastatic MTC. At a peptide amount of approximately 1 microg, maximum tumour uptake (8.9+/-2.9%ID/g) was observed in animals at 1 h post injection, with tumour-to-blood ratios as high as 6.3+/-1.9. Physiological CCK-B receptors in the stomach, gallbladder and pancreas of the mice were targeted as well. The major route of excretion was renal, but strong evidence for a biliary excretion pathway also exists. Pilot therapy studies with 131I-labelled gastrin showed significant anti-tumour efficacy as compared with untreated controls. In accordance with the preclinical data, good receptor targeting was observed in the tumour sites, stomach, gallbladder and pancreas of a patient with metastatic MTC. These data suggest that gastrin and its analogues may represent a useful new class of receptor binding peptides for diagnosis and therapy of a variety of tumour types, including MTC and small cell lung cancer. Future preclinical and clinical studies will address in more detail the molecular features that render CCK-B receptor binding agents potentially useful candidates for in vivo scintigraphy and radionuclide therapy.


Assuntos
Gastrinas/uso terapêutico , Radioisótopos do Iodo/uso terapêutico , Radioimunodetecção , Radioimunoterapia , Receptores da Colecistocinina/análise , Idoso , Animais , Carcinoma Medular/diagnóstico por imagem , Carcinoma Medular/radioterapia , Estudos de Viabilidade , Humanos , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/radioterapia , Distribuição Tecidual
9.
Arch Environ Contam Toxicol ; 19(6): 807-15, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2256702

RESUMO

English sole (Parophyrs vetulus) in Puget Sound, Washington, USA are at risk of hepatocarcinogenesis specifically in areas adjacent to polluting industrial effluents. A question concerning population and ecosystem survival is whether any of the effects of etiopathologic change are reversible. This has been approached by looking for evidence of tumor accelerating effects in an exposed population. Cellular parameters were determined by flow cytometry for hepatocytes of English sole. Cells containing hyperdiploid DNA not present in fish from reference waters, Port Madison, were found in all non-tumor-bearing and tumor bearing fish taken from a polluted site, Eagle Harbor, where incidence of hepatic neoplasia approaches 30%. Induction of altered DNA content in the exposed general hepatocyte population suggests environmental induction rather than an association with lesions per se. In contrast, glutathione levels in hepatocytes (0.8-3.2 nmol/mg protein), were little influenced by the exposure site, consistent with the apparent lack of protection against chemically induced carcinogenesis in English sole. Association of altered DNA content with exposure site is significant for its potential contribution to biological acceleration and evidence of tumor promotion found at the tissue and organismic levels. The results support the notion that hepatocarcinogenesis in English sole in Eagle Harbor has a multi-year exposure etiology, in which potentially reversible accelerating influences have a role, and that glutathione conjugation is an inadequate mode of detoxification for these fish.


Assuntos
DNA/análise , Linguados/metabolismo , Citometria de Fluxo , Glutationa/análise , Fígado/química , Poluentes Químicos da Água/toxicidade , Animais , Doenças dos Peixes/induzido quimicamente , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/veterinária
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