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1.
Bull Entomol Res ; 108(6): 792-799, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29441836

RESUMO

Arthropod communities in the tropics are increasingly impacted by rapid changes in land use. Because species showing distinct seasonal patterns of activity are thought to be at higher risk of climate-related extirpation, global warming is generally considered a lower threat to arthropod biodiversity in the tropics than in temperate regions. To examine changes associated with land use and weather variables in tropical arthropod communities, we deployed Malaise traps at three major anthropogenic forests (secondary reserve forest, oil palm forest, and urban ornamental forest (UOF)) in Peninsular Malaysia and collected arthropods continuously for 12 months. We used metabarcoding protocols to characterize the diversity within weekly samples. We found that changes in the composition of arthropod communities were significantly associated with maximum temperature in all the three forests, but shifts were reversed in the UOF compared with the other forests. This suggests arthropods in forests in Peninsular Malaysia face a double threat: community shifts and biodiversity loss due to exploitation and disturbance of forests which consequently put species at further risk related to global warming. We highlight the positive feedback mechanism of land use and temperature, which pose threats to the arthropod communities and further implicates ecosystem functioning and human well-being. Consequently, conservation and mitigation plans are urgently needed.


Assuntos
Artrópodes/fisiologia , Biodiversidade , Florestas , Chuva , Animais , Arecaceae/crescimento & desenvolvimento , Malásia , Dinâmica Populacional , Estações do Ano , Temperatura
2.
Respir Res ; 18(1): 16, 2017 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-28088206

RESUMO

BACKGROUND: There are challenges for researchers and clinicians to select the most appropriate physical activity tool, and a balance between precision and feasibility is needed. Currently it is unclear which physical activity tool should be used to assess physical activity in Bronchiectasis. The aim of this research is to compare assessment methods (pedometer and IPAQ) to our criterion method (ActiGraph) for the measurement of physical activity dimensions in Bronchiectasis (BE), and to assess their feasibility and acceptability. METHODS: Patients in this analysis were enrolled in a cross-sectional study. The ActiGraph and pedometer were worn for seven consecutive days and the IPAQ was completed for the same period. Statistical analyses were performed using SPSS 20 (IBM). Descriptive statistics were used; the percentage agreement between ActiGraph and the other measures were calculated using limits of agreement. Feedback about the feasibility of the activity monitors and the IPAQ was obtained. RESULTS: There were 55 (22 male) data sets available. For step count there was no significant difference between the ActiGraph and Pedometer, however, total physical activity time (mins) as recorded by the ActiGraph was significantly higher than the pedometer (mean ± SD, 232 (75) vs. 63 (32)). Levels of agreement between the two devices was very good for step count (97% agreement); and variation in the levels of agreement were within accepted limits of ±2 standard deviations from the mean value. IPAQ reported more bouted- moderate - vigorous physical activity (MVPA) [mean, SD; 167(170) vs 6(9) mins/day], and significantly less sedentary time than ActiGraph [mean, SD; 362(115) vs 634(76) vmins/day]. There were low levels of agreement between the two tools (57% sedentary behaviour; 0% MVPA10+), with IPAQ under-reporting sedentary behaviour and over-reporting MVPA10+ compared to ActiGraph. The monitors were found to be feasible and acceptable by participants and researchers; while the IPAQ was accepta ble to use, most patients required assistance to complete it. CONCLUSIONS: Accurate measurement of physical activity is feasible in BE and will be valuable for future trials of therapeutic interventions. ActiGraph or pedometer could be used to measure simple daily step counts, but ActiGraph was superior as it measured intensity of physical activity and was a more precise measure of time spent walking. The IPAQ does not appear to represent an accurate measure of physical activity in this population. TRIAL REGISTRATION: Clinical Trials Registration Number NCT01569009 : Physical Activity in Bronchiectasis.


Assuntos
Acelerometria/instrumentação , Actigrafia/instrumentação , Bronquiectasia/diagnóstico , Bronquiectasia/fisiopatologia , Exercício Físico , Inquéritos e Questionários , Acelerometria/métodos , Actigrafia/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Ambulatorial/instrumentação , Monitorização Ambulatorial/métodos , Irlanda do Norte , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Bull Entomol Res ; 105(4): 515-20, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25913190

RESUMO

Chinese knotweed (Persicaria chinensis) is of ecological and economic importance as a high-risk invasive species and a traditional medicinal herb. However, the insects associated with P. chinensis pollination have received scant attention. As a widespread invasive plant we would expect P. chinensis to be associated with a diverse group of insect pollinators, but lack of taxonomic identification capacity is an impediment to confirm this expectation. In the present study we aimed to elucidate the insect pollinators of P. chinensis in peninsular Malaysia using DNA barcoding. Forty flower visitors, representing the range of morphological diversity observed, were captured at flowers at Ulu Kali, Pahang, Malaysia. Using Automated Barcode Gap Discovery, 17 morphospecies were assigned to 23 species representing at least ten families and four orders. Using the DNA barcode library (BOLD) 30% of the species could be assigned a species name, and 70% could be assigned a genus name. The insects visiting P. chinensis were broadly similar to those previously reported as visiting Persicaria japonica, including honey bees (Apis), droneflies (Eristalis), blowflies (Lucilia) and potter wasps (Eumedes), but also included thrips and ants.


Assuntos
Código de Barras de DNA Taxonômico , Insetos/genética , Polinização/fisiologia , Polygonaceae/fisiologia , Animais , Insetos/classificação , Insetos/fisiologia , Malásia
4.
Bull Entomol Res ; 105(6): 717-27, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26344799

RESUMO

Metabarcoding, the coupling of DNA-based species identification and high-throughput sequencing, offers enormous promise for arthropod biodiversity studies but factors such as cost, speed and ease-of-use of bioinformatic pipelines, crucial for making the leapt from demonstration studies to a real-world application, have not yet been adequately addressed. Here, four published and one newly designed primer sets were tested across a diverse set of 80 arthropod species, representing 11 orders, to establish optimal protocols for Illumina-based metabarcoding of tropical Malaise trap samples. Two primer sets which showed the highest amplification success with individual specimen polymerase chain reaction (PCR, 98%) were used for bulk PCR and Illumina MiSeq sequencing. The sequencing outputs were subjected to both manual and simple metagenomics quality control and filtering pipelines. We obtained acceptable detection rates after bulk PCR and high-throughput sequencing (80-90% of input species) but analyses were complicated by putative heteroplasmic sequences and contamination. The manual pipeline produced similar or better outputs to the simple metagenomics pipeline (1.4 compared with 0.5 expected:unexpected Operational Taxonomic Units). Our study suggests that metabarcoding is slowly becoming as cheap, fast and easy as conventional DNA barcoding, and that Malaise trap metabarcoding may soon fulfill its potential, providing a thermometer for biodiversity.


Assuntos
Artrópodes/genética , Código de Barras de DNA Taxonômico/métodos , Primers do DNA , Animais , Biodiversidade , DNA Mitocondrial/química , Complexo IV da Cadeia de Transporte de Elétrons/química , Complexo IV da Cadeia de Transporte de Elétrons/genética , Sequenciamento de Nucleotídeos em Larga Escala , Metagenômica , Técnicas de Amplificação de Ácido Nucleico , Reação em Cadeia da Polimerase
5.
Osteoarthritis Cartilage ; 22(10): 1568-76, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25278066

RESUMO

OBJECTIVE: To compare quantitative magnetization transfer (qMT) parameters of patellar cartilage measured using cross-relaxation imaging (CRI) in asymptomatic volunteers and patients with osteoarthritis. DESIGN: The study was performed with Institutional Review Board approval and with all subjects signing informed consent. CRI of the knee joint was performed at 3.0T on 20 asymptomatic volunteers and 11 patients with osteoarthritis. The fraction of macromolecular bound protons (f), the exchange rate constant between macromolecular bound protons and free water protons (k), and the T2 relaxation time of macromolecular bound protons (T2(B)) of patellar cartilage were measured. Mann-Whitney-Wilcoxon rank-sum tests were used to compare qMT parameters between asymptomatic volunteers and patients with osteoarthritis. RESULTS: Average f, k, and T2(B) of patellar cartilage was 12.46%, 7.22 s(-1), and 6.49 µs respectively for asymptomatic volunteers and 12.80%, 6.13 s(-1), and 6.80 µs respectively for patients with osteoarthritis. There were statistically significant differences between groups of subjects for k (P < 0.01) and T2(B) (P < 0.0001) but not f (P = 0.38) of patellar cartilage. CONCLUSION: Patients with osteoarthritis had significantly lower k and significantly higher T2(B) of patellar cartilage than asymptomatic volunteers which suggests that qMT parameters can detect changes in the macromolecular matrix of degenerative cartilage.


Assuntos
Cartilagem Articular/patologia , Imageamento por Ressonância Magnética/métodos , Osteoartrite do Joelho/patologia , Patela/patologia , Articulação Patelofemoral/patologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão Sinal-Ruído , Adulto Jovem
6.
Genet Mol Res ; 13(1): 920-5, 2014 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-24634112

RESUMO

Bats are important flagship species for biodiversity research; however, diversity in Southeast Asia is considerably underestimated in the current checklists and field guides. Incorporation of DNA barcoding into surveys has revealed numerous species-level taxa overlooked by conventional methods. Inclusion of these taxa in inventories provides a more informative record of diversity, but is problematic as these species lack formal description. We investigated how frequently documented, but undescribed, bat taxa are encountered in Peninsular Malaysia. We discuss whether a barcode library provides a means of recognizing and recording these taxa across biodiversity inventories. Tissue was sampled from bats trapped at Pasir Raja, Dungun Terengganu, Peninsular Malaysia. The DNA was extracted and the COI barcode region amplified and sequenced. We identified 9 species-level taxa within our samples, based on analysis of the DNA barcodes. Six specimens matched to four previously documented taxa considered candidate species but currently lacking formal taxonomic status. This study confirms the high diversity of bats within Peninsular Malaysia (9 species in 13 samples) and demonstrates how DNA barcoding allows for inventory and documentation of known taxa lacking formal taxonomic status.


Assuntos
Biodiversidade , Quirópteros/classificação , Quirópteros/genética , Código de Barras de DNA Taxonômico , Animais , Evolução Molecular , Malásia , Filogenia
7.
Ann Burns Fire Disasters ; 36(4): 276-280, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38680239

RESUMO

A review of paediatric burns in our burns facility in the United Kingdom demonstrated variable accuracy of size, and a majority documented as <1% total body surface area (TBSA). Accurate assessment is important for medical records, clinical management and non-accidental injuries. We propose to assess burn size with a coin-based system, where small burns are described by single/multiple sterling coins. Participants were asked about their confidence in evaluating small paediatric burns. Participants were given ten scenarios which included photographs of paediatric patients with small burns. They were asked to assess burn size in their normal manner (TBSA, measurement) and with a coin-based system. The 'burns' were drawn on children based on a given coin size and percentage so that the accuracy of the participant's answer was quantifiable. Participants provided qualitative feedback in a questionnaire on the coin-based system. Thirty nurses and medical staff of varying seniority actively involved in referral/management of paediatric burns took part, creating over 300 responses. In preliminary questions, 66% of participants did not feel confident in estimating paediatric burns and 83% needed to refer to a paediatric burns chart. Accuracy of burn size using TBSA and the coin-based system was 45% and 67%, respectively. The majority (97%) stated estimating size was easier, and 93% found it more accurate. A total of 87% found communication between colleagues easier. Results highlight the improved assessment of small burns in our hospital using a coin-based approach in comparison to TBSA, and could facilitate accurate communication between health care professionals.


En revoyant les évaluations de SB des brûlures pédiatrique dans notre centre du Royaume Uni, nous avons constaté une grande variabilité quant à leur exactitude, avec une majorité d'entre elles touchant moins de 1%. Hors, une évaluation exacte est nécessaire pour la stratégie thérapeutique, la bonne tenue du dossier et sur le plan légal (en particulier après brûlure non accidentelle). Nous proposons, pour ces petites brûlures, une évaluation utilisant la taille d'une pièce de monnaie. Les volontaires à cette étude se sont vus remettre 10 scenarii de petites brûlures, photos à l'appui. Il leur était demandé d'évaluer la SB comme à leur habitude et en utilisant le système de taille de pièce (avec multiples si nécessaire), et d'estimer l'intérêt de l'évaluation « à la pièce ¼. Trente personnels (médecins et infirmières) expérimentés ont participé, générant réponses. En préambule, 66% des participants s'estimaient peu fiables quand à l'évaluation des SB de l'enfant et 83% utilisaient des tables spécifiques. L'exactitude de l'évaluation était de 45% avec les techniques habituelles et 67% à la pièce. La grande majorité estimait que la mesure à la pièce facilitait l'évaluation (97%), la rendait plus précise (93%) et facilitait les transmissions (87%). L'évaluation à la pièce des brûlures pédiatriques pourrait la rendre plus précise et faciliter la communication entre professionnels.

8.
Trop Biomed ; 35(2): 501-510, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33601825

RESUMO

Blastocystis sp. is ubiquitous in avian, mammalian and human hosts and propagates in either neutral or slightly alkaline conditions within the host's gastro-intestinal tract. Of the few previous studies on this enteric protozoan parasite in feline and canine hosts, prevalence values have been shown to range between 0 to 70.8%. In view of the close association between humans, and canine and feline hosts as companion animals, faecal samples of 180 Felis catus and 82 Canis lupus, collected from Penang and Kuala Lumpur, Malaysia, were initially screened by in vitro cultivation followed by molecular characterization. No positive isolates were identified in culture but in 12 feline samples DNA barcoding detected a zoonotic subtype Blastocystis ST1 for the first time. Consequently, avian and human isolates, which had previously been successfully cultured, were used to investigate the impact of pH on the viability and morphology of Blastocystis sp. The use of Trypan blue showed that the number of viable cells increased when exposed to pH 4 and a significant increase in viability occurred in pH values of 5 to 7. Development of Blastocystis cells in both isolates was suppressed in media less than pH 5 followed by the disappearance of viable cells from avian isolates in more acidic media below pH 4. Morphologically at pH 4 cells from avian isolates were less rounded, and with wrinkled / shrunken surfaces, than the more normal rounded cells from human isolates. On the other hand, at values below pH 3, no viable cells in human isolates were visible. The present findings therefore confirm that gastro-intestinal pH is an important determinant of Blastocystis viability and consequently influences the epidemiology of infection within avian, mammalian and human hosts.

9.
Acta Trop ; 171: 138-140, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28359829

RESUMO

Mosquitoes are vectors of various human diseases in the tropics including yellow fever, dengue, malaria and West Nile virus. Mosquitoes can act as vectors between wildlife and humans, which is particularly important for diseases where wild animals serve as reservoirs of parasites in the absence of human infections. Research has mainly focused on the medical impacts of Anopheles, Aedes, Mansonia and Culex, however, very little attention has been directed towards other mosquito genera, especially those which act as vectors of diseases of wildlife. We have observed adults of Mimomyia (Etorleptiomyia) luzonensis (Ludlow, 1905) feeding on a toad, Ingerophrynus parvus, near an oil palm plantation settlement in Setia Alam, Selangor state, Peninsular Malaysia. Mimomyia is known to feed on reptiles and amphibians, and is a documented vector of several arboviruses, including West Nile virus. The observation of Mimomyia feeding on a common toad near a human settlement highlights a need to understand the relationships between mosquitoes, toads and humans from an ecological perspective. We report on-site observations of the feeding habit of Mimomyia; the first records from Malaysia.


Assuntos
Culicidae/fisiologia , Comportamento Alimentar/fisiologia , Animais , Bufonidae , Culicidae/virologia , Humanos , Malásia
10.
Biochim Biophys Acta ; 1313(2): 89-94, 1996 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-8781554

RESUMO

A dietary deficiency of copper (CuD) is associated with a 50-70% and a 2-fold increase in hepatic reduced glutathione (GSH) concentration and synthesis, respectively, which leads to a 50-80% increase in plasma GSH. Moreover, the kidneys of CuD rats remove 40% more GSH from the blood than copper adequate (CuA) rats. These findings have led us to propose that the increase in hepatic synthesis of GSH in CuD rats is accompanied by a comparable increase in the hepatic expression of gamma-glutamylcysteine synthetase (gamma-GCS), the rate limiting enzyme of glutathione biosynthesis, and that the enhanced uptake of GSH by the kidney would lead to a compensatory decrease in renal gamma-GCS expression. In experiment I, male weanling rats (3-4 weeks) were ad libitum fed a CuD (0.5 microgram Cu/g) or CuA (5.8 micrograms/g) diet for 70 days; and in experiment II, male weanling rats were pair-meal fed the CuD or CuA diet for 35 days. In both studies, CuD diet caused a significant increase in hepatic GSH concentration, but hepatic gamma-GCS activity and mRNA abundance were unchanged. In contrast, renal GSH concentration was unaffected by the CuD diet. However, renal gamma-GCS activity was reduced 40% and this was paralleled by a 50% decrease in gamma-GCS mRNA. Moreover, the decrease in renal gamma-GCS mRNA was caused by a reduction in renal gamma-GCS gene transcription. The results of these studies indicate that the increase in renal uptake of GSH resulting from a dietary Cu deficiency is associated with a compensatory decrease in gamma-GCS expression.


Assuntos
Cobre/deficiência , Glutamato-Cisteína Ligase/metabolismo , Rim/enzimologia , Fígado/enzimologia , Animais , Dieta , Regulação Enzimológica da Expressão Gênica , Glutationa/metabolismo , Masculino , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Transcrição Gênica
11.
J Clin Oncol ; 15(5): 1897-905, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9164200

RESUMO

PATIENTS AND METHODS: We conducted a randomized, multicenter study of intravenous cyclophosphamide 500 mg/m2 plus fluorouracil 500 mg/m2 combined with either mitoxantrone (Novantrone, Lederle Cyanamid Canada Ltd, Willowdale, Ontario) 10 mg/m2 (CNF) or doxorubicin (Adriamycin, Adria Laboratories of Canada Ltd, Mississauga, Ontario) 50 mg/m2 (CAF) every 3 weeks in advanced breast cancer. RESULTS: The response rate in 249 randomized patients was 36% with CNF (44 of 121) and 48% with CAF (62 of 128) (P = .054), with complete remissions in 10 patients (8.3%) on CNF and in 13 (10.2%) on CAF. If only fully assessable patients are considered, the response rate was 48% (44 of 91) with CNF and 60% (62 of 103) with CAF (P = .098). At time of analysis, all except 10 patients (one CNF and nine CAF) had died. The median survival time with CAF was longer than with CNF (15.2 v 10.9 months; P = .003), and time to progression was also longer with CAF (5.3 v 3.2 months; P < .03). Survival differences remained significant (P = .006) if patients who failed to meet all eligibility criteria were excluded. Favorable prognostic factors for survival in a Cox regression model included good performance status (P < .0001); less than two organ systems involved by tumor (P < .0001); no involvement of lung, liver, or brain (P < .003); involvement of bone or bone marrow (P < .009), prior surgery for breast cancer (P < .006); being premenopausal (P < .03); > or = 3 years from diagnosis until randomization on this study (P < .03); and treatment with CAF (P < .03). Alopecia > or = grade 3 was reported in 55% of patients with CAF and 12% of patients with CNF (P < .001), while other > or = grade 3 toxicities did not differ significantly. Priestman-Baum quality-of-life assessment was comparable on the two study arms. CONCLUSION: In patients with advanced breast cancer, CAF was associated with longer survival than was CNF, with an increase in alopecia, but not in other toxicities.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Esquema de Medicação , Feminino , Fluoruracila/administração & dosagem , Humanos , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Análise de Sobrevida
12.
J Clin Oncol ; 14(6): 1756-64, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8656243

RESUMO

PURPOSE: To investigate the benefit of chemotherapy in patients with symptomatic hormone-resistant prostate cancer using relevant end points of palliation in a randomized controlled trial. PATIENTS AND METHODS: We randomized 161 hormone-refractory patients with pain to receive mitoxantrone plus prednisone or prednisone alone (10 mg daily). Nonresponding patients on prednisone could receive mitoxantrone subsequently. The primary end point was a palliative response defined as a 2-point decrease in pain as assessed by a 6-point pain scale completed by patients (or complete loss of pain if initially 1 +) without an increase in analgesic medication and maintained for two consecutive evaluations at least 3 weeks apart. Secondary end points were a decrease of > or = 50% in use of analgesic medication without an increase in pain, duration of response, and survival. Health-related quality of life was evaluated with a series of linear analog self-assessment scales (LASA and the Prostate Cancer-Specific Quality-of-Life Instrument [PROSQOLI]), the core questionnaire of the European Organization for Research and Treatment of Cancer (EORTC), and a disease-specific module. RESULTS: Palliative response was observed in 23 of 80 patients (29%; 95% confidence interval, 19% to 40%) who received mitoxantrone plus prednisone, and in 10 of 81 patients (12%; 95% confidence interval, 6% to 22%) who received prednisone alone (P = .01). An additional seven patients in each group reduced analgesic medication > or = 50% without an increase in pain. The duration of palliation was longer in patients who received chemotherapy (median, 43 and 18 weeks; P < .0001, log-rank). Eleven of 50 patients randomized to prednisone treatment responded after addition of mitoxantrone. There was no difference in overall survival. Treatment was well tolerated, except for five episodes of possible cardiac toxicity in 130 patients who received mitoxantrone. Most responding patients had an improvement in quality-of-life scales and a decrease in serum prostate-specific antigen (PSA) level. CONCLUSION: Chemotherapy with mitoxantrone and prednisone provides palliation for some patients with symptomatic hormone-resistant prostate cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cuidados Paliativos , Neoplasias da Próstata/tratamento farmacológico , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma/secundário , Idoso , Analgésicos/uso terapêutico , Antagonistas de Androgênios/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Estudos Cross-Over , Resistencia a Medicamentos Antineoplásicos , Humanos , Masculino , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Mitoxantrona/efeitos adversos , Orquiectomia , Dor/etiologia , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Antígeno Prostático Específico/análise , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Qualidade de Vida , Taxa de Sobrevida
13.
J Chromatogr A ; 1380: 55-63, 2015 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-25596759

RESUMO

Actinium-225 (t1/2=9.92d) is an α-emitting radionuclide with nuclear properties well-suited for use in targeted alpha therapy (TAT), a powerful treatment method for malignant tumors. Actinium-225 can also be utilized as a generator for (213)Bi (t1/2 45.6 min), which is another valuable candidate for TAT. Actinium-225 can be produced via proton irradiation of thorium metal; however, long-lived (227)Ac (t1/2=21.8a, 99% ß(-), 1% α) is co-produced during this process and will impact the quality of the final product. Thus, accurate assays are needed to determine the (225)Ac/(227)Ac ratio, which is dependent on beam energy, irradiation time and target design. Accurate actinium assays, in turn, require efficient separation of actinium isotopes from both the Th matrix and highly radioactive activation by-products, especially radiolanthanides formed from proton-induced fission. In this study, we introduce a novel, selective chromatographic technique for the recovery and purification of actinium isotopes from irradiated Th matrices. A two-step sequence of cation exchange and extraction chromatography was implemented. Radiolanthanides were quantitatively removed from Ac, and no non-Ac radionuclidic impurities were detected in the final Ac fraction. An (225)Ac spike added prior to separation was recovered at ≥ 98%, and Ac decontamination from Th was found to be ≥ 10(6). The purified actinium fraction allowed for highly accurate (227)Ac determination at analytical scales, i.e., at (227)Ac activities of 1-100 kBq (27 nCi to 2.7 µCi).


Assuntos
Actínio/isolamento & purificação , Prótons , Tório/isolamento & purificação , Cromatografia por Troca Iônica , Humanos , Extração Líquido-Líquido , Tório/efeitos da radiação
14.
Br J Pharmacol ; 129(3): 465-70, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10711344

RESUMO

1. This study examined the role of [Ca2+]I and Ca(2+)-dependent kinases in the modulation of high-affinity, mammalian brain-specific L-proline transporter (PROT). 2. beta-PMA (phorbol 12-myristate 13-acetate), an activator of protein kinase C (PKC), inhibits PRO uptake, and bisindolymalemide I (BIM), a potent PKC inhibitor, prevents beta-PMA inhibition. Down-regulation of PKC by chronic treatment with beta-PMA enhances PROT function indicating PROT regulation by tonic activity of PKC. 3. Thapsigargin, which increases [Ca2+]I levels by inhibiting Ca(2+)-ATPase, inhibits PROT and exhibits additive inhibition when co-treated with beta-PMA. KN-62, a Ca2+/calmodulin-dependent kinase II (CaMK II) inhibitor, but not BIM (a PKC inhibitor) prevents the inhibition by thapsigargin. These data suggest that PKC and CaMK II modulate PROT and that thapsigargin mediates its effect via CaMK II. 4. Thapsigargin raises [Ca2+]I and increases PRO-induced current on a second time scale, whereas the inhibitory effect of thapsigargin occurs only after 10 min of treatment. These data suggest that Ca2+ differentially regulate PROT: Ca2+ initially enhances PRO transport but eventually inhibits transport function through CaMK II pathway. 5. Ca(2+)-induced stimulation exemplifies the acute regulation of a neurotransmitter transporter, which may play a critical role in the profile of neurotransmitters during synaptic transmission.


Assuntos
Sistemas de Transporte de Aminoácidos Neutros , Química Encefálica/fisiologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/fisiologia , Cálcio/fisiologia , Proteínas de Membrana Transportadoras/metabolismo , Química Encefálica/genética , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Linhagem Celular , DNA Complementar/genética , Regulação para Baixo/efeitos dos fármacos , Ativadores de Enzimas , Inibidores Enzimáticos/farmacologia , Humanos , Indicadores e Reagentes , Rim/efeitos dos fármacos , Rim/metabolismo , Proteínas de Membrana Transportadoras/genética , Transmissão Sináptica/fisiologia , Acetato de Tetradecanoilforbol/farmacologia , Tapsigargina/farmacologia , Transfecção
15.
J Virol Methods ; 96(1): 5-16, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11516484

RESUMO

Hepatitis C virus (HCV) infection is very common among chronic hemodialysis patients. In the past, blood transfusion appeared to be the primary risk factor; however evidence of nosocomial HCV transmission in the hemodialysis setting has recently been reported. This report describes a molecular investigation of HCV isolates obtained from a population of 670 patients attending six different Seattle-King County based hemodialysis centers in order to identify potential common source infections. 733 serum specimens were collected from hemodialysis patients in 1992 and 1996, and were tested for HCV antibodies and RNA. Overall, 115 of 670 (17%) patients were positive for HCV RNA, and thus were considered actively infected by HCV. HCV genotype was determined in all cases by restriction fragment length polymorphism, and 93 patients were found to be infected by HCV genotype 1. HCV envelope genes were amplified from the 93 patients with genotype 1 infection, and were studied in further detail by heteroduplex tracking analysis (HTA) using genotype 1a and 1b specific probes derived from the envelope 1 (E1) and envelope 2 (E2) genes. Genetic relatedness between pairs of HCV envelope genes was estimated by calculating the degree of gel shift relative to homoduplex controls. Nucleotide sequencing and phylogenetic analysis was used to confirm genetic relatedness detected by HTA. When HTA was performed using the E1 gene probe, 12 apparently related infections were detected; 10 of 12 (83%) of these infections were confirmed as truly related using the gold standard method of nucleotide sequencing plus phylogenetic analysis. Using an E2 gene probe, 24 infections were apparently related, but only six (25%) were confirmed by sequencing. As a control, 41 envelope genes, which were unrelated by HTA, were sequenced; 0 of 41 (0%) were truly related. In summary, HTA provides a rapid and effective molecular technique for screening HCV genetic relatedness in population-based studies, and should prove valuable in future studies of HCV molecular epidemiology.


Assuntos
Variação Genética , Hepacivirus/genética , Hepatite C/epidemiologia , Análise Heteroduplex , Diálise Renal/efeitos adversos , Hepacivirus/classificação , Hepatite C/virologia , Humanos , Epidemiologia Molecular , Filogenia , Prevalência , RNA Viral/sangue , Análise de Sequência de DNA
16.
Health Psychol ; 15(1): 3-10, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8788535

RESUMO

The present study examined whether training in cognitive coping skills would enhance pain coping strategies and alter pain perception in adults with sickle cell disease (SCD). Sixty-four African Americans with SCD were randomly assigned to either a cognitive coping skills condition (three 45-min sessions in which patients were trained to use 6 cognitive coping strategies) or a disease-education control condition (three 45-min didactic-discussion sessions about SCD). Pain sensitivity to calibrated noxious stimulation was measured at pre- and posttesting, as were cognitive coping strategies, clinical pain, and health behaviors. Results indicated that, compared with the randomly assigned control condition, brief training in cognitive coping skills resulted in increased coping attempts, decreased negative thinking, and lower tendency to report pain during laboratory-induced noxious stimulation.


Assuntos
Adaptação Psicológica , Anemia Falciforme/complicações , Terapia Cognitivo-Comportamental/métodos , Dor/psicologia , Adulto , Negro ou Afro-Americano , Análise de Variância , Anemia Falciforme/psicologia , Atitude , Teoria da Decisão , Discriminação Psicológica , Feminino , Humanos , Masculino , North Carolina , Dor/etiologia , Limiar da Dor/psicologia , Educação de Pacientes como Assunto
17.
Clin J Pain ; 13(2): 110-5, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9186018

RESUMO

OBJECTIVE: The current study assessed stability of pain coping strategies over an 18-month period in adults, adolescents, and young children with sickle cell disease. DESIGN: Eighteen-month longitudinal study. Assessments of coping strategies were done at baseline, 9 months, and 18 months. PATIENTS: A total of 141 patients with sickle cell disease (SCD) presenting to adult and pediatric sickle cell clinics for regularly scheduled check-ups. OUTCOME MEASURES: Coping Strategy Questionnaire subscales (Coping Attempts, Negative Thinking, and Illness-Focused Strategies). RESULTS: pearson Product-Moment correlation coefficients comparing baseline and 18-month follow-up coping data were highly significant for Coping Attempts and Negative Thinking/Illness Focused Strategies for adults. For young children, the 18-month follow-up scores on Negative Thinking were significantly correlated with baseline scores, however, no other 18-month correlations were significant. The results from the adolescent subset of subjects indicated no significant correlations on any of the coping strategies from baseline to 18-month-follow-up. Stability was also assessed using intraclass correlations, which incorporates more than two test-retest values on the same subjects. These analyses confirmed that coping strategies in adults were highly stable, whereas for children and adolescents, there was instability ANOVAs indicated that adolescents scored significantly higher than young children on Negative Thinking and Illness-Focused Strategies at baseline and follow-up. CONCLUSIONS: As compared with the highly stable coping evidenced in adults with SCD, coping in children and adolescents with SCD is more variable. Thus, interventions should target children early before maladaptive coping patterns become entrenched.


Assuntos
Adaptação Psicológica/fisiologia , Anemia Falciforme/complicações , Anemia Falciforme/psicologia , Dor/etiologia , Dor/psicologia , Adolescente , Adulto , Criança , Estudos Transversais , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
18.
Biotechnol Prog ; 6(5): 370-5, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-1366874

RESUMO

Fluidized bed adsorption using a high-density synthetic resin has proven to be an invaluable technique for separating novel compounds from unfiltered fermentation broths during the very early stages of fermentation development, where product concentrations are typically in the parts per million range. Previous initial downstream processing strategies consisted of cell separation from whole broth or direct extraction with water-immiscible solvents, both of which resulted in lengthy time cycles, conflicts with existing operations requiring the use of high-cost centrifugal separators, and environmental/solvent recovery concerns. Laboratory and subsequent pilot plant process development work along with concomitant improvements in yield, quality, and time cycles are presented for one of several fluidized bed processes piloted in Merck's Natural Product Isolation facility.


Assuntos
Fermentação , Tacrolimo/análogos & derivados , Tecnologia Farmacêutica/métodos , Adsorção , Fenômenos Químicos , Físico-Química , Meios de Cultura , Compostos Heterocíclicos/química , Estrutura Molecular , Resinas Vegetais , Streptomyces/metabolismo , Tecnologia Farmacêutica/instrumentação
19.
Am J Surg ; 159(2): 208-10; discussion 210-1, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2301714

RESUMO

We report our results in eight consecutive patients with idiopathic subclavian-axillary vein thrombosis treated at a community hospital with systemic streptokinase therapy. Seven of the eight patients were treated within 1 week of symptoms. All seven patients had partial or total recanalization documented by venography. One patient developed rethrombosis that did not respond to therapy with tPA and had mild persisting symptoms of postphlebitic syndrome. None of the other patients had symptoms of postphlebitic syndrome on follow-up up to 5 years' duration.


Assuntos
Veia Axilar , Estreptoquinase/uso terapêutico , Veia Subclávia , Terapia Trombolítica , Trombose/tratamento farmacológico , Adulto , Heparina/uso terapêutico , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Recidiva , Estreptoquinase/administração & dosagem , Varfarina/uso terapêutico
20.
J Bone Joint Surg Am ; 77(2): 214-24, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7844127

RESUMO

The hepatitis-C virus has been the most prevalent cause of chronic hepatitis in both blood and organ recipients. The introduction of a second-generation immunoassay for antibodies to the hepatitis-C virus (HCV 2.0) provided the opportunity to determine if the hepatitis-C virus can be transmitted through tissue transplantation. Banked sera from tissue donors that had previously been found to be non-reactive to the first-generation hepatitis-C virus antibody assay (HCV 1.0) and non-reactive for antibodies to hepatitis-B core antigen were retested with HCV 2.0. The sera from two donors were reactive; the transplant records of recipients of tissues from these donors were reviewed, and the surgeons or hospitals were contacted. The tissue recipients were tested with HCV 2.0, and positive sera were tested for hepatitis-C virus RNA by polymerase chain reaction. Viral nucleic acids isolated from viremic donors and recipients were analyzed for identity by sequencing of the hepatitis-C virus envelope gene (E2) hypervariable region. There were twenty-one grafts, which had been treated with gamma radiation, from one donor; thirteen had been transplanted to twelve recipients. Serum samples from six of the recipients were tested; one was reactive. This patient had other risk factors for infection with the hepatitis-C virus, and sequence analysis demonstrated non-identity between the donor and recipient hepatitis-C virus isolates. Nine of twelve grafts from a second donor had been transplanted in nine recipients. Serum samples from five patients were tested with HCV 2.0; four were reactive. In three of the four patients, the sera were determined to be positive for the hepatitis-C virus by polymerase chain reaction. E2 sequence analyses of hepatitis-C virus RNA isolates from two of these recipients demonstrated sequence identity with the donor isolate. The results of the present report demonstrate that the hepatitis-C virus can be transmitted by bone, ligament, and tendon allografts. They also support the need for testing of all tissue donors for antibodies to the hepatitis-C virus before the tissue is released for transplantation. The results also suggest that seventeen kilo-gray of gamma radiation may inactivate the hepatitis-C virus in tissue.


Assuntos
Transplante Ósseo/efeitos adversos , Hepacivirus , Hepatite C/transmissão , Transplante de Tecidos/efeitos adversos , Adolescente , Adulto , Idoso , Sequência de Aminoácidos , Sequência de Bases , Busca de Comunicante , DNA Viral/análise , Feminino , Raios gama , Genes env , Hepacivirus/isolamento & purificação , Hepacivirus/efeitos da radiação , Anticorpos Anti-Hepatite/sangue , Hepatite C/imunologia , Humanos , Immunoblotting , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Análise de Sequência de DNA , Tendões/transplante , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética
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