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1.
Genomics ; 115(3): 110625, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37068644

RESUMO

Precise regulation of transcription in gene expression is critical for all aspects of normal organism form, fitness, and function and even minor alterations in the level, location, and timing of gene expression can result in phenotypic variation within and between species including evolutionary innovations and human disease states. Eukaryotic transcription is regulated by a complex interplay of multiple factors working both at a physical and molecular levels influencing this process. In Saccharomyces cerevisiae, the TF with the greatest number of putative regulatory targets is the essential gene Repressor Activator Protein 1 (RAP1). While much is known about the roles of Rap1 in gene regulation and numerous cellular processes, the response of Rap1 target genes to systematic titration of RAP1 expression level remains unknown. To fill this knowledge gap, we used a strain with a tetracycline-titratable promoter replacing wild-type regulatory sequences of RAP1 to systematically reduce the expression level of RAP1 and followed this with RNA sequencing (RNA-seq) to measure genome-wide gene expression responses. Previous research indicated that Rap1 plays a significant regulatory role in particular groups of genes including telomere-proximal genes, homothallic mating (HM) loci, glycolytic genes, DNA repair genes, and ribosomal protein genes; therefore, we focused our analyses on these groups and downstream targets to determine how they respond to reductions in RAP1 expression level. Overall, despite being known as both an activator and as a repressor of its target genes, we found that Rap1 acts as an activator for more target genes than as a repressor. Additionally, we found that Rap1 functions as an activator of ribosomal protein genes and a repressor for HM loci genes consistent with predictions from the literature. Unexpectedly, we found that Rap1 functions as a repressor of glycolytic enzyme genes contrary to prior reports of it having the opposite effect. We also compared the expression of RAP1 to five different genes related to DNA repair pathway and found that decreasing RAP1 downregulated four of those five genes. Finally, we found no effect of RAP1 depletion on telomere-proximal genes despite its functioning to silence telomeric repeat-containing RNAs. Together our results enrich our understanding of this important transcriptional regulator.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Humanos , Saccharomyces cerevisiae/genética , Fator de Transcrição AP-1/genética , Proteínas de Saccharomyces cerevisiae/genética , Complexo Shelterina , Proteínas de Ligação a Telômeros/genética , Proteínas de Ligação a Telômeros/metabolismo , Proteínas Ribossômicas/genética , Expressão Gênica , Regulação Fúngica da Expressão Gênica , Proteínas Fúngicas/genética , Fatores de Transcrição/metabolismo
2.
Tijdschr Psychiatr ; 66(1): 42-45, 2024.
Artigo em Holandês | MEDLINE | ID: mdl-38380487

RESUMO

A 29-year-old man developed priapism following the (re)administration of zuclopentixol. In the previous days, a significant amount of alcohol was consumed, presumably in combination with amphetamine and cannabis. Priapism is a rare but serious side effect of various psychoactive medications and recreational drugs, leading to permanent loss of erectile function if not treated in time. In this case the side effect was discovered in a late stage, at which curative treatment was no longer viable. A clear guideline for choosing an alternative antipsychotic agent is currently lacking, but an antipsychotic with low alfa-adrenergic affinity seems preferable. To prevent erectile disfunction following priapism, awareness of its severity is essential, for both doctor and patient.


Assuntos
Antipsicóticos , Priapismo , Masculino , Humanos , Adulto , Priapismo/induzido quimicamente , Priapismo/tratamento farmacológico , Antipsicóticos/efeitos adversos , Clopentixol
3.
Inorg Chem ; 61(19): 7217-7221, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35510902

RESUMO

Here we show that the praseodymium N,N-dimethylaminodiboranate complex Pr(H3BNMe2BH3)3 and the 2,2,6,6-tetramethylheptane-3,5-dionate complex Pr(thd)3 can serve as volatile carriers for 225Ac. The actinium coordination complexes Ac(H3BNMe2BH3)3 and Ac(thd)3 are the likely species subliming with the carrier material. A sample of 225Ac-doped Pr(H3BNMe2BH3)3 was used to deposit amorphous 225Ac-doped praseodymium boride films on glass and Si(100) at 300 °C. The α emission spectra of the refractory films are well-resolved, suggesting that they could be used as radioactive implants for brachytherapy and related treatments.


Assuntos
Braquiterapia , Praseodímio , Actínio , Compostos de Boro
4.
Tijdschr Psychiatr ; 62(5): 340-350, 2020.
Artigo em Holandês | MEDLINE | ID: mdl-32484562

RESUMO

BACKGROUND: In the Netherlands, unemployed people in sick leave, can get sickness payment from the Employee Insurance Agency (UWV), so called 'vangnetters' (users of a safety net). They participated in a day-care program for people with psychological work-related complaints together with people in sick leave who were employed by an employer who were referred to a university psychiatric center (UCP).
AIM: Comparison of both groups on initial complaints and treatment outcome.
METHOD: A retrospective explorative study (during an 11-years period) comparing start and follow-up measurements by using questionnaires.
RESULTS: The UWV group (n = 111) differed from the UCP group (n = 254) at the start of the program: longer sickness leave, more severe initial complaints and a few other coping strategies. One year after finishing the program, 61% of the UWV group and 83% of the UCP group were in paid employment. People who were not in paid employment after a year already had more initial complaints compared to people who were back at work. The length of sickness leave was not a limiting factor for reintegration in work.
CONCLUSION: Differences in initial symptoms and coping strategies did not really lead to differences in perspective of reintegration in work. Cooperation with the UWV for employed as well as unemployed people in sick leave led to good treatment results.


Assuntos
Emprego , Licença Médica , Humanos , Países Baixos , Estudos Retrospectivos , Inquéritos e Questionários
5.
Ann Oncol ; 28(2): 400-407, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27831506

RESUMO

Background: The purpose of our study was to characterize the causes of death among cancer patients as a function of objectives: (i) calendar year, (ii) patient age, and (iii) time after diagnosis. Patients and methods: US death certificate data in Surveillance, Epidemiology, and End Results Stat 8.2.1 were used to categorize cancer patient death as being due to index-cancer, nonindex-cancer, and noncancer cause from 1973 to 2012. In addition, data were characterized with standardized mortality ratios (SMRs), which provide the relative risk of death compared with all persons. Results: The greatest relative decrease in index-cancer death (generally from > 60% to < 30%) was among those with cancers of the testis, kidney, bladder, endometrium, breast, cervix, prostate, ovary, anus, colorectum, melanoma, and lymphoma. Index-cancer deaths were stable (typically >40%) among patients with cancers of the liver, pancreas, esophagus, and lung, and brain. Noncancer causes of death were highest in patients with cancers of the colorectum, bladder, kidney, endometrium, breast, prostate, testis; >40% of deaths from heart disease. The highest SMRs were from nonbacterial infections, particularly among <50-year olds (e.g. SMR >1,000 for lymphomas, P < 0.001). The highest SMRs were typically within the first year after cancer diagnosis (SMRs 10-10,000, P < 0.001). Prostate cancer patients had increasing SMRs from Alzheimer's disease, as did testicular patients from suicide. Conclusion: The risk of death from index- and nonindex-cancers varies widely among primary sites. Risk of noncancer deaths now surpasses that of cancer deaths, particularly for young patients in the year after diagnosis.


Assuntos
Cardiopatias/mortalidade , Neoplasias/mortalidade , Causas de Morte , Seguimentos , Humanos , Fatores de Risco , Programa de SEER , Fatores de Tempo , Estados Unidos/epidemiologia
6.
Scand J Prim Health Care ; 35(3): 286-292, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28768444

RESUMO

OBJECTIVE: A validated measure to gather patient feedback on physicians' empathy is not available in Swedish. The objective for this study was to examine the psychometric characteristics of a Swedish version of the Consultation and Relational Empathy (CARE) measure (widely used in English). DESIGN, SETTING AND PATIENTS: The CARE measure was translated into Swedish and tested on 554 unselected patients visiting physicians in two primary care clinics in northwestern Stockholm, Sweden. MAIN OUTCOME MEASURES: Adequate translation, as well as reliability and validity of the Swedish CARE measure. RESULTS: The Swedish CARE measure seemed to demonstrate high acceptability and face validity when consulting a physician. The mean CARE score 41.5 (SD 8.9) over all 10 item was not significantly influenced by seasonality, age or gender. Scores were somewhat negatively distributed, but corrected item-total correlations were high (0.86-0.91) suggesting homogeneity. Internal reliability was very high (Cronbach's alpha 0.975). Factor analysis implied a one-dimensional structure with factor loadings between 0.89 and 0.93. CONCLUSIONS: The Swedish CARE measure appears to be psychometrically valid and reliable enough in physicians.


Assuntos
Empatia , Relações Médico-Paciente , Inquéritos e Questionários/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Encaminhamento e Consulta , Reprodutibilidade dos Testes , Suécia , Tradução , Traduções , Adulto Jovem
7.
Infection ; 41(5): 991-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23653428

RESUMO

PURPOSE: Colistin is increasingly used as the last-resort treatment option against infections caused by multidrug-resistant (MDR) Gram-negative pathogens, but its nephrotoxicity is of concern, especially in severely ill patients. The aim of this study was to analyze the toxicity of colistin therapy in adults and children with hematological malignancies (HM) and hematopoietic stem cell transplantation (HSCT) recipients. METHODS: Data on HSCT recipients and HM patients, treated with intravenous colistin (2.5-5 mg/kg/day in children and 3-6 million international units (IU) in adults, adjusted to renal function) during the period 2008-2011 in our center, were retrospectively collected and analyzed. Nephrotoxicity was defined according to the RIFLE criteria (Risk, Injury, Failure, Loss, and End-stage kidney disease). RESULTS: Twenty-nine children and adults received 38 courses of intravenous colistin (2.5-5 mg/kg/day in children and 3-6 × 10(6) IU in adults, adjusted to renal function) [allogeneic HSCT (22 courses) and HM (16 courses)] for 3-28 days (median 10 days) for empirical therapy for nosocomial clinical sepsis (28) or local infection (6), and bacteremia with MDR Gram-negative rods (4). Nephrotoxicity was observed at the end of 4 (10.5%) courses. In 32 (84%) courses, nephrotoxic medications were concomitantly administered. Two patients had convulsions, probably unrelated to colistin. Seven patients (18%) died while on colistin therapy. No death was attributed to an adverse effect of colistin. CONCLUSIONS: Treatment with intravenous colistin, with dosage adjusted to renal function, was relatively safe for HM/HSCT patients, even with concomitantly administered nephrotoxic medications. Concern about nephrotoxicity should not justify a delay in initiating empirical colistin treatment in situations where infection with MDR Gram-negative rods is likely.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/efeitos adversos , Colistina/administração & dosagem , Colistina/efeitos adversos , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Neoplasias Hematológicas/microbiologia , Transplante de Células-Tronco Hematopoéticas , Adolescente , Adulto , Idoso , Bacteriemia/tratamento farmacológico , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
8.
Pediatr Blood Cancer ; 60(9): E85-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23589280

RESUMO

X-linked lymphoproliferative syndrome (XLP) is caused by mutations in SH2D1A, and is associated with overwhelming infectious mononucleosis, aplastic anemia, hypogammaglobulinemia, and B-cell lymphomas. However, the frequency of SH2D1A mutations in males who present with B NHL is unknown. Five cases of XLP were diagnosed among 158 males presenting with B NHL (approximately 3.2%). Four of the patients had two episodes of B NHL and one had a single episode of B NHL followed by aggressive infectious mononucleosis. Prospective screening for XLP in males with B-cell lymphoma at the time of initial diagnosis should be considered.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/genética , Transtornos Linfoproliferativos/genética , Mutação , Sistema de Registros , Seguimentos , Humanos , Linfoma Difuso de Grandes Células B , Transtornos Linfoproliferativos/diagnóstico , Transtornos Linfoproliferativos/patologia , Transtornos Linfoproliferativos/terapia , Masculino , Estudos Retrospectivos , Proteína Associada à Molécula de Sinalização da Ativação Linfocitária
9.
Nat Med ; 5(3): 309-13, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10086387

RESUMO

In principle, transplantation of mesenchymal progenitor cells would attenuate or possibly correct genetic disorders of bone, cartilage and muscle, but clinical support for this concept is lacking. Here we describe the initial results of allogeneic bone marrow transplantation in three children with osteogenesis imperfecta, a genetic disorder in which osteoblasts produce defective type I collagen, leading to osteopenia, multiple fractures, severe bony deformities and considerably shortened stature. Three months after osteoblast engraftment (1.5-2.0% donor cells), representative specimens of trabecular bone showed histologic changes indicative of new dense bone formation. All patients had increases in total body bone mineral content ranging from 21 to 29 grams (median, 28), compared with predicted values of 0 to 4 grams (median, 0) for healthy children with similar changes in weight. These improvements were associated with increases in growth velocity and reduced frequencies of bone fracture. Thus, allogeneic bone marrow transplantation can lead to engraftment of functional mesenchymal progenitor cells, indicating the feasibility of this strategy in the treatment of osteogenesis imperfecta and perhaps other mesenchymal stem cell disorders as well.


Assuntos
Células da Medula Óssea/citologia , Transplante de Medula Óssea , Mesoderma/citologia , Osteoblastos/citologia , Osteogênese Imperfeita/terapia , Células-Tronco/citologia , Densidade Óssea , Transplante de Medula Óssea/efeitos adversos , Pré-Escolar , Feminino , Células-Tronco Hematopoéticas/citologia , Humanos , Lactente , Masculino , Osteogênese/fisiologia
10.
J Vet Pharmacol Ther ; 34(5): 487-93, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21198678

RESUMO

Beta-lactam antimicrobials, commonly used in both veterinary and human medicine, generally present short biologic half-lives, whereas their activity is enhanced as pathogen exposure is prolonged. These properties necessitate multiple-dose regimens of standard dosage forms, thereby hampering pet owner adherence, frequently resulting in therapeutic failure. This study presents a novel controlled-release gastroretentive oral drug delivery system for beta-lactams with which single-dose administration provides an effective antimicrobial course, optimizing pharmacokinetic (PK)-pharmacodynamic (PD) profiles, minimizing adverse effects and emergence of antimicrobial resistance and facilitating adherence. Our prototype sustained-delivery swelling-tablet (SDST), based on a degradable hydrophilic polymeric matrix, was designed to enable continuous input of these drugs to their absorption sites over several days. Several SDST formulations of the beta-lactam amoxicillin were evaluated in in vitro dissolution studies. Two formulations were selected for further in vivo canine studies, for determination of gastric retention and PK-PD profiling. Prolonged gastric retention times maintaining allowed for maintained effective drug concentrations against many clinically relevant pathogens for more than 48 h for one formulation and more than 5 days for the other. Both SDST formulations offer significant advantages over standard immediate-release therapy in achieving PK-PD goals and enhancing adherence. The prototypical formulations represent a novel platform which may be modified to meet various clinical requirements.


Assuntos
Implantes Absorvíveis/veterinária , Amoxicilina/administração & dosagem , Amoxicilina/farmacocinética , Cabras/sangue , Amoxicilina/sangue , Animais , Área Sob a Curva , Preparações de Ação Retardada , Cabras/metabolismo , Meia-Vida
11.
J Vet Pharmacol Ther ; 34(5): 494-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21198679

RESUMO

Dosage forms of antimicrobials play a critical role in facilitating the attainment of pharmacokinetic-pharmacodynamic (PK-PD) targets as well as adherence in both veterinary and human medicine. The purpose of this study was to develop and evaluate a controlled-release subcutaneous amoxicillin implant for single-dose therapy of large ruminants such as goats, sheep, and deer. The degradable implant, designed to attain PK-PD targets following single administration, was evaluated for amoxicillin release rate and time-concentration profile. In vitro release studies demonstrated constant-rate release of approximately 40% of amoxicillin content within 96 h. In an in vivo study in goats, serving as a model for target animals, a serum concentration of approximately 0.4 mg/L was achieved within 8 h of implant insertion and maintained for >6 days. In comparison, in control goats given a standard single intramuscular amoxicillin dose of 15 mg/kg, amoxicillin peaked at 1.2 mg/L after 1 h, rapidly dropping to below detection level at 8 h. These results suggest that the proposed implant offers a unique modality for animal caregivers to conveniently administer a full antimicrobial course following a single dose of an efficient PK-PD-optimized dosage form. Furthermore, modifications of implant composition may allow for tailoring of its characteristics to various PK, PD, microbiological, and clinical requirements.


Assuntos
Implantes Absorvíveis/veterinária , Amoxicilina/administração & dosagem , Amoxicilina/farmacocinética , Cabras/sangue , Animais , Preparações de Ação Retardada , Cabras/metabolismo
12.
J Affect Disord ; 265: 185-192, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-32090740

RESUMO

AIMS: Earlier studies show that participation in mind and body exercises (MBE) is cross-sectionally associated with high levels of depressive symptoms and antidepressants. This study investigates the longitudinal interrelationship between depressive symptoms, MBE and antidepressants. METHODS: 3269 men and 4318 women aged 24-74 years participated in the Swedish Longitudinal Occupational Survey of Health (SLOSH). Measures of MBE practice and depressive symptoms were drawn from the SLOSH questionnaire, data on prescription drugs were obtained from the Swedish Prescribed Drug Register. Structural Equation Modeling (SEM) was used to analyze temporal relationships. RESULTS: Both MBE practice and antidepressants in 2012 was associated with higher levels of depressive symptoms two years later. Depressive symptoms in turn were associated with higher levels of later MBE practice and antidepressants. These relationships seemed to be explained by confounding by indication and were of higher magnitude for antidepressants than for MBE. CONCLUSION: Overall, SEM analysis shows that MBE and antidepressant treatment were both bi-directionally associated with depressive symptoms over time. Part of the explanation is likely to be confounding by indication: those with symptoms of depression more likely to undertake treatment, and MBE alone may be more common among those with less severe depression. The results clarify some of our findings from earlier studies and give some important, new information on what people are doing to manage depressive symptoms on a societal level, regarding self-care, medication, and the combination of both.


Assuntos
Antidepressivos , Depressão , Adulto , Idoso , Antidepressivos/uso terapêutico , Depressão/epidemiologia , Exercício Físico , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Suécia/epidemiologia , Adulto Jovem
13.
J Autism Dev Disord ; 50(8): 2973-2986, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32052317

RESUMO

We compared the presence of autistic and comorbid psychopathology and functional impairments in young adults who received a clinical diagnosis of Pervasive Developmental Disorders Not Otherwise Specified or Asperger's Disorder during childhood to that of a referred comparison group. While the Autism Spectrum Disorder group on average scored higher on a dimensional ASD self- and other-report measure than clinical controls, the majority did not exceed the ASD cutoff according to the Autism Diagnostic Observation Schedule. Part of the individuals with an ASD diagnosis in their youth no longer show behaviors that underscribe a clinical ASD diagnosis in adulthood, but have subtle difficulties in social functioning and a vulnerability for a range of other psychiatric disorders.


Assuntos
Síndrome de Asperger/epidemiologia , Transtorno do Espectro Autista/epidemiologia , Transtorno do Espectro Autista/psicologia , Adolescente , Adulto , Síndrome de Asperger/diagnóstico , Transtorno do Espectro Autista/diagnóstico , Criança , Comorbidade , Feminino , Humanos , Masculino , Transtornos Mentais , Adulto Jovem
14.
Cytotherapy ; 11(2): 245-55, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19152153

RESUMO

From 4 to 5 April 2008, international experts met for the second time in Tubingen, Germany, to present and discuss the latest proceedings in research on non-hematopoietic stem cells (NHSC). This report presents issues of basic research including characterization, isolation, good manufacturing practice (GMP)-like production and imaging as well as clinical applications focusing on the regenerative and immunomodulatory capacities of NHSC.


Assuntos
Células-Tronco Adultas/citologia , Pesquisa Biomédica , Células-Tronco Embrionárias/citologia , Imunoterapia Adotiva , Neoplasias/terapia , Células-Tronco Adultas/fisiologia , Pesquisa Biomédica/ética , Pesquisa Biomédica/métodos , Pesquisa Biomédica/tendências , Técnicas de Cultura de Células , Diferenciação Celular , Movimento Celular , Transdiferenciação Celular , Diagnóstico por Imagem , Células-Tronco Embrionárias/fisiologia , Perfilação da Expressão Gênica , Alemanha , Mobilização de Células-Tronco Hematopoéticas , Humanos , Medicina Regenerativa/tendências , Nicho de Células-Tronco
15.
Science ; 193(4258): 1117-9, 1976 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-17792747

RESUMO

The predicted flux on the earth of solar neutrinos has eluded detection, confounding current ideas of solar energy production by nuclear fusion. The dominant low-energy component of that flux can be detected by mass-spectrometric assay of the induced tiny concentration of 1.6 x 10(7) year lead-205 in old thallium minerals. Comments are solicited from those in all relevant disciplines.

16.
Cytotherapy ; 10(8): 771-4, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19089685

RESUMO

In recent years mesenchymal stromal cells (MSC) have emerged as a major new form of cell therapy. While the original perception was that MSC were stem/progenitor cells with the potential to contribute to the regeneration of tissue, more recent data suggest that the principal mechanism of MSC activity is through the release of soluble mediators that elicit the observed biologic response. Future studies are needed to identify more completely the spectrum of therapeutic applications and delineate better the associated molecular and cellular mechanisms.


Assuntos
Citocinas/metabolismo , Doença Enxerto-Hospedeiro/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Osteogênese Imperfeita/terapia , Animais , Diferenciação Celular , Movimento Celular , Regeneração Tecidual Guiada/tendências , Humanos , Transplante de Células-Tronco Mesenquimais/tendências , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia
17.
Appl Radiat Isot ; 140: 18-23, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29936271

RESUMO

This work presents a complete scheme for the selective separation of actinium and radium isotopes from bulk 232Th target material, in a process that may be applied in a separation scheme for the production of 225Ac by proton spallation on thorium. Thorium metal is dissolved in sulfuric acid with small amounts of HF. Actinium and radium are retained on cation exchange resin from the sulfate medium, while neutral and anionic thorium sulfate complexes are rejected. Following rinsing steps to remove residual thorium, actinium and radium are recovered from the cation exchange resin using 5 M HNO3. Further separations of actinium via extraction chromatography with UTEVA and DGA resins yield actinium in >92% yield, while providing additional decontamination from thorium and other spallation byproducts. The radium fraction can be further processed following ingrowth of 225Ac from 225Ra to produce additional 225Ac free from any potential 227Ac impurity.

18.
Appl Radiat Isot ; 65(4): 428-34, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17126023

RESUMO

We present a new simple approach for automated, non-destructive measurement of the alpha-emitting radium isotopes ((223)Ra, (224)Ra, and (226)Ra) in water based on the emanation of their respective radon daughters ((219)Rn, (220)Rn, and (222)Rn). The method combines the high adsorption uptake of MnO(2) Resin for radium (K(d)=2.4 x 10(4)ml/g) over a wide pH range with the simplicity of the activity registration using a commercial radon-in-air analyzer (RAD7, DURRIDGE Company, Inc). Radium is first adsorbed onto the MnO(2) Resin by passing a water sample through the resin packed in a gas-tight glass cartridge. The same cartridge is then connected to the radon analyzer via a simple tubing system to circulate air through the resin and a drying system. The efficiency of the proposed system is determined by running standards prepared in the same manner. Our results indicate that the efficiency for (226)Ra is >22% if both (218)Po and (214)Po counts are collected. This is comparable with typical efficiencies for alpha spectrometry but with much less sample preparation. We estimate that an MDA of 0.8 pCi/L for (226)Ra may be obtained with this new approach using a 1L water sample and less than 4h of counting.


Assuntos
Rádio (Elemento)/análise , Poluentes Radioativos da Água/análise , Automação , Calibragem , Compostos de Manganês/química , Óxidos/química , Radiometria/instrumentação , Radiometria/métodos
19.
Biochim Biophys Acta ; 1313(2): 95-100, 1996 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-8781555

RESUMO

Chondrocytes have been shown to possess two types of histamine receptors, H1 and H2. The application of histamine to isolated porcine chondrocytes was found to significantly increase intracellular calcium and this increase was partially dependent upon the presence of extracellular calcium. This, therefore, implies that there is some role for a plasma membrane calcium transport system in the increase of cytosolic calcium in response to histamine. The increase in intracellular calcium in response to the application of histamine was found to be reduced by both H1 and H2 receptor antagonists.


Assuntos
Cálcio/metabolismo , Cartilagem Articular/metabolismo , Histamina/farmacologia , Animais , Células Cultivadas , Clorfeniramina/farmacologia , Citosol/metabolismo , Antagonistas dos Receptores Histamínicos H1/farmacologia , Antagonistas dos Receptores H2 da Histamina/farmacologia , Lantânio/metabolismo , Ranitidina/farmacologia , Receptores Histamínicos H1/fisiologia , Transdução de Sinais , Suínos
20.
J Clin Oncol ; 22(14): 2856-64, 2004 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15254053

RESUMO

PURPOSE: To define further the role of concurrent chemoradiotherapy for patients with advanced squamous carcinoma of the head and neck. PATIENTS AND METHODS: The Radiation Therapy Oncology Group developed this three-arm randomized phase II trial. Patients with stage III or IV squamous carcinoma of the oral cavity, oropharynx, or hypopharynx were eligible. Each of three arms proposed a radiation schedule of 70 Gy in 35 fractions. Patients on arm 1 were to receive cisplatin 10 mg/m(2) daily and fluorouracil (FU) 400 mg/m(2) continuous infusion (CI) daily for the final 10 days of treatment. Treatment on arm 2 consisted of hydroxyurea 1 g every 12 hours and FU 800 mg/m(2)/d CI delivered with each fraction of radiation. Arm 3 patients were to receive weekly paclitaxel 30 mg/m(2) and cisplatin 20 mg/m(2). Patients randomly assigned to arms 1 and 3 were to receive their treatments every week; patients on arm 2 were to receive their therapy every other week. RESULTS: Between 1997 and 1999, 241 patients were entered onto study; 231 were analyzable. Ninety-two percent, 79%, and 83% of patients on arms 1, 2, and 3, respectively, were able to complete their radiation as planned or with an acceptable variation. Fewer than 10% of patients had unacceptable deviations or incomplete chemotherapy in the three arms. Estimated 2-year disease-free and overall survival rates were 38.2% and 57.4% for arm 1, 48.6% and 69.4% for arm 2, and 51.3% and 66.6% for arm 3. CONCLUSION: We have demonstrated that three different approaches of concurrent multiagent chemotherapy and radiation were feasible and could be delivered to patients in a multi-institutional setting with high compliance rates.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/patologia , Cisplatino/administração & dosagem , Terapia Combinada , Estudos de Viabilidade , Feminino , Fluoruracila/administração & dosagem , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Hidroxiureia/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Paclitaxel/administração & dosagem , Dosagem Radioterapêutica , Análise de Sobrevida , Resultado do Tratamento
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