RESUMO
AIMS: To evaluate the sensor performance of the FreeStyle Libre intermittently viewed continuous glucose monitoring system using reference blood glucose levels during moderate-intensity exercise while on either full or reduced basal insulin dose in people with Type 1 diabetes. METHODS: Ten participants with Type 1 diabetes [four women, mean ± sd age 31.4 ± 9.0 years, BMI 25.5±3.8 kg/m2 , HbA1c 55±7 mmol/mol (7.2±0.6%)] exercised on a cycle ergometer for 55 min at a moderate intensity for 5 consecutive days at the clinical research facility, while receiving either their usual or a 75% basal insulin dose. After a 4-week washout period, participants performed the second exercise period having switched to the alternative basal insulin dose. During exercise, reference capillary blood glucose values were analysed using the fully enzymatic-amperometric method and compared with the interstitial glucose values obtained. Intermittently viewed continuous glucose monitoring accuracy was analysed according to median (interquartile range) absolute relative difference, and Clarke error grid and Bland-Altman analysis for overall glucose levels during exercise, stratified by glycaemic range and basal insulin dosing scheme (P<0.05). RESULTS: A total of 845 glucose values were available during exercise to evaluate intermittently viewed continuous glucose monitoring sensor performance. The median (interquartile range) absolute relative difference between the reference values and those obtained by the sensor across the glycaemic range overall was 22 (13.9-29.7)%, and was 36.3 (24.2-45.2)% during hypoglycaemia, 22.8 (14.6-30.6)% during euglycaemia and 15.4 (9-21)% during hyperglycaemia. Usual basal insulin dose was associated with a worse sensor performance during exercise compared with the reduced (75%) basal insulin dose [median (interquartile range) absolute relative difference: 23.7 (17.2-30.7)% vs 20.5 (12-28.1)%; P<0.001). CONCLUSIONS: The intermittently viewed continuous glucose monitoring sensor showed diminished accuracy during exercise. Absolute glucose readings derived from the sensor should be used cautiously and need confirmation by additional finger-prick blood glucose measurements.
Assuntos
Glicemia/análise , Diabetes Mellitus Tipo 1/sangue , Equipamentos e Provisões , Exercício Físico/fisiologia , Adulto , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/normas , Automonitorização da Glicemia/instrumentação , Estudos Cross-Over , Diabetes Mellitus Tipo 1/tratamento farmacológico , Relação Dose-Resposta a Droga , Desenho de Equipamento , Equipamentos e Provisões/normas , Feminino , Humanos , Insulina/administração & dosagem , Sistemas de Infusão de Insulina , Masculino , Valor Preditivo dos Testes , Adulto JovemRESUMO
AIM: The pharmacodynamic characteristics of the basal insulin analogues insulin detemir (IDet) and insulin glargine (IGlar) have been examined extensively via euglycaemic clamp studies. However, differences in clamp methodology and in the analysis of clamp data between trials have led to confusion over the duration of action of these two insulins. The aim of this study was to address these ambiguities in the literature by assessing the pharmacodynamic properties of IDet and IGlar over 30 h under single-dose and steady-state conditions using the definitions and procedures previously standardized by Heise and Pieber in 2007. METHODS: This was a single-centre, randomized, double-blind, glucose clamp trial involving 36 patients with type 1 diabetes. RESULTS: The mean duration of action of IDet was 25.9 h, compared with 19.8 h for IGlar after a single-dose (NS), and 23.3 h (IDet) versus 27.1 h (IGlar) at steady-state (p < 0.0001). IDet had a significantly higher area under the curve glucose infusion rate (AUCGIR ) than IGlar over 0-12 h after a single-dose (p = 0.0018). The steady-state AUCGIR for IDet was numerically higher than IGlar over 0-12 h (728 vs. 592 mg/kg, respectively; p = NS), but significantly lower than IGlar at 12-30 h (p = 0.0003). CONCLUSIONS: The duration of action of IDet is 23 h (range: 4.0-30.0), while that of IGlar is 27 h (range: 10.5-29.0) (95% CI: -8.1, 0.6). This suggests both insulins can be used for once-daily dosing, but individual needs must be considered.
Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemiantes/farmacologia , Insulina de Ação Prolongada/farmacologia , Adolescente , Adulto , Área Sob a Curva , Glicemia/metabolismo , Diabetes Mellitus Tipo 1/sangue , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Técnica Clamp de Glucose , Humanos , Hipoglicemiantes/administração & dosagem , Insulina Detemir , Insulina Glargina , Insulina de Ação Prolongada/administração & dosagem , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Management of diabetes in elderly subjects is complex and careful management of glucose levels is of particular importance in this population because of an increased risk of diabetes-related complications and hypoglycaemia. OBJECTIVE: The aim of this study was to evaluate the pharmacokinetic and pharmacodynamic properties of insulin degludec (IDeg), a basal insulin with an ultra-long duration of action, in elderly subjects with type 1 diabetes compared with younger adults. METHODS: This trial was a randomised, double-blind, two-period, crossover trial conducted in a single centre and included both inpatient and outpatient periods. Subjects were men and women aged 18-35 years inclusive (younger adult group) or ≥65 years (elderly group) with type 1 diabetes who received IDeg (0.4 U/kg) via subcutaneous injection in the thigh once-daily for six days. Following 6-day dosing, a 26-hour euglycaemic glucose clamp procedure was conducted to evaluate the steady-state pharmacodynamic effects of IDeg. Blood samples were taken for pharmacokinetic analysis up to 120 h post-dose. Pharmacokinetic endpoints included the total exposure of IDeg, ie the area under the IDeg serum concentration curve during one dosing interval at steady state (AUC(IDeg,τ,SS)) (τ = 0-24 h, equal to one dosing interval) and the maximum IDeg serum concentration at steady state (C(max,IDeg,SS)). Pharmacodynamic endpoints included the total glucose-lowering effect of IDeg, ie the area under the glucose infusion rate (GIR) curve at steady state (AUC(GIR,τ,SS)), and the maximum GIR at steady state (GIR(max,IDeg,SS)). RESULTS: Total exposure (AUC(IDeg,τ,SS)) and maximum concentration (C(max,IDeg,SS)) of IDeg were comparable between elderly subjects and younger adults. Estimated mean age group ratios (elderly/younger adult) for AUC(IDeg,τ,SS) and C(max,IDeg,SS) and corresponding two-sided 95 % confidence intervals (CIs) were 1.04 (95 % CI 0.73-1.47) and 1.02 (95 % CI 0.74-1.39), respectively. Mean AUC(IDeg,0-12h,SS)/AUC(IDeg,τ,SS) was 53 % in both younger adult and elderly subjects, showing that in both age groups IDeg exposure was evenly distributed across the first and second 12 h of the 24-hour dosing interval. No statistically significant differences were observed between younger adult and elderly subjects with regard to AUC(GIR,τ,SS) (the primary endpoint of this study) and GIR(max,IDeg,SS). Estimated mean age group ratios (elderly/younger adult) for AUC(GIR,τ,SS) and GIR(max,IDeg,SS) and corresponding two-sided 95 % CIs were 0.78 (95 % CI 0.47-1.31) and 0.80 (95 % CI 0.54-1.17), respectively. Duration of action was beyond the clamp duration of 26 h in all subjects. CONCLUSIONS: The exposure of IDeg at steady state during once-daily dosing was similar in younger adult and elderly subjects. The glucose-lowering effect of IDeg was numerically lower in elderly subjects compared with younger adults, but no significant differences were observed between age groups. The ultra-long pharmacokinetic and pharmacodynamic properties of IDeg observed in younger adults were preserved in elderly subjects with type 1 diabetes. Clinical trials.gov number: NCT00964418.
Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Insulina de Ação Prolongada/farmacologia , Insulina de Ação Prolongada/farmacocinética , Adolescente , Adulto , Idoso , Diabetes Mellitus Tipo 1/sangue , Método Duplo-Cego , Feminino , Técnica Clamp de Glucose , Humanos , Insulina de Ação Prolongada/efeitos adversos , Insulina de Ação Prolongada/uso terapêutico , Masculino , Segurança , Adulto JovemRESUMO
PURPOSE: The management of high-risk endometrial cancer (HREC) remains controversial. We conducted a prospective multicenter phase-II clinical trial to evaluate an adjuvant chemotherapy (CT) with sequential radiotherapy (RT) in patients with HREC. METHODS: Patients with HREC from 8 institutions in Germany were enrolled. After surgery, patients received four cycles of paclitaxel 175 mg/m² (P) and carboplatin AUC5 (C) (d1, q21d) and subsequent external pelvic radiation therapy (1.8 Gy/d, d1-5) at a total dose of 45 Gy with vaginal brachytherapy (3 × 5 Gy). Quality of life (QoL) was assessed using the EORTC-QLQ-C30 questionnaire. Primary endpoints were tolerability, toxicity and QoL. Progression-free survival (PFS) was defined as secondary endpoint. RESULTS: Thirty-five patients were enrolled from 2004 through 2008. Median follow-up was 24 months (range 3-24 months). All patients received 4 cycles of P and C and completed RT. Overall, grade 3/4 haematological toxicity was 25.6 %. Three cycles were delayed because of leukopenia. Grade 3/4 non-haematologic toxicities were rare (≤3 %). No overall change in QoL occurred during treatment. Two-year median PFS and OS rates were both 75.8 %. CONCLUSIONS: Adjuvant combination CT with P + C and sequential RT is well tolerated and a feasible regimen in patients with HREC. Subsequent phase-III trials are warranted.
Assuntos
Quimiorradioterapia Adjuvante , Neoplasias do Endométrio/terapia , Endométrio/efeitos dos fármacos , Endométrio/efeitos da radiação , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Braquiterapia/efeitos adversos , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Carboplatina/uso terapêutico , Quimiorradioterapia Adjuvante/efeitos adversos , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/cirurgia , Endométrio/patologia , Endométrio/cirurgia , Estudos de Viabilidade , Feminino , Seguimentos , Alemanha/epidemiologia , Doenças Hematológicas/epidemiologia , Doenças Hematológicas/etiologia , Humanos , Incidência , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Paclitaxel/uso terapêutico , Prognóstico , Qualidade de Vida , Análise de SobrevidaRESUMO
AIMS: To compare the pharmacodynamic properties of insulin detemir (detemir) and neutral protamine lispro (NPL) insulin using a euglycaemic glucose clamp. METHODS: In a double-blind, crossover study, 30 patients with C-peptide negative type 1 diabetes were randomly assigned to a single dose (0.4 U/kg) of detemir and NPL. Plasma glucose (PG) was normalized with a variable insulin infusion and then decreased stepwise, followed by a euglycaemic clamp at 5.5 mmol/l over 32 h. Duration of action was defined as time from dosing until PG exceeded 8.3 mmol/l for at least 30 min. RESULTS: Duration of action was similar for detemir [23.0 (range 2.25-32) h] and NPL [22.0 (9.5-32) h], p = 0.55. Using glucose infusion rate (GIR) parameters, detemir showed a flatter pharmacodynamic profile versus NPL: area under the curve, AUC(GIR) ((0-32)) = 1326 vs. 1841 mg/kg, p < 0.01 (detemir vs. NPL, respectively); AUC(GIR) ((0-12)) = 784 vs. 1392 mg/kg, p < 0.05; AUC(GIR) ((12-32)) = 455 vs. 274 mg/kg, p = 0.051; GIR(late) (12-32)/GIR(early) (0-12) ratio = 0.33 vs. 0.04, p < 0.001. Detemir also showed a lower and later peak of action than NPL [GIR(max) 2.0 vs. 3.2 mg/kg/min, p < 0.01; T(max) 9.1 (95% confidence interval: 3.0-14.7) vs. 7.0 h (1.8-15.2)]. CONCLUSIONS: Detemir and NPL had similar duration of action of approximately 24 h in patients with type 1 diabetes. Compared with NPL, detemir had a flatter profile with a more even distribution of metabolic effect over 24 h.
Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Técnica Clamp de Glucose/métodos , Hipoglicemiantes/farmacologia , Insulina de Ação Prolongada/farmacologia , Insulina/análogos & derivados , Protaminas/farmacologia , Adulto , Área Sob a Curva , Glicemia/metabolismo , Índice de Massa Corporal , Estudos Cross-Over , Diabetes Mellitus Tipo 1/sangue , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Insulina/farmacologia , Insulina Detemir , Insulina de Ação Prolongada/administração & dosagem , Masculino , Protaminas/administração & dosagemRESUMO
Treatment with rituximab is highly effective for EBV-associated post transplant lymphoproliferative disease. However, little is known about its immunological sequelae in pediatric allogeneic hematopoietic SCT (HSCT). Time to normal CD19+ B-lymphocyte values in blood and intravenous immunoglobulin (IVIG) substitution needed to maintain an IgG>400 mg per 100 ml in six consecutive pediatric allogeneic HSCT patients treated with rituximab for symptomatic EBV reactivation were compared with a matched cohort of non-rituximab-treated patients. Follow-up of the six patients ranged from 149 to 1546 days; all but one survived. The mean (+/-s.d.) time to recovery of CD19+ B-lymphocytes was 353+/-142 days as compared with 139+/-42 in the controls (P<0.01). Similarly, substitution of IVIG as a measure of functional B-cell recovery was extended from a mean of 122+/-45 to a mean of 647+/-320 days, and the cumulative dose of IVIG increased from a mean of 1.86+/-0.51 to 4.4+/-0.97 g/kg, respectively (P<0.05). One patient had functional B-lymphocyte deficiency for >3 years and ultimately required two stem cell boosts. Rituximab is a live-saving treatment for pediatric HSCT patients but may lead to prolonged and even persistent B-cell deficiency.
Assuntos
Anticorpos Monoclonais/administração & dosagem , Linfócitos B/fisiologia , Hematopoese/efeitos dos fármacos , Transplante de Células-Tronco Hematopoéticas/métodos , Transtornos Linfoproliferativos/terapia , Adolescente , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Murinos , Antineoplásicos/uso terapêutico , Linfócitos B/efeitos dos fármacos , Criança , Pré-Escolar , Feminino , Herpesvirus Humano 4 , Humanos , Imunoglobulinas Intravenosas/administração & dosagem , Lactente , Cinética , Transtornos Linfoproliferativos/tratamento farmacológico , Transtornos Linfoproliferativos/virologia , Masculino , Rituximab , Transplante Homólogo , Ativação ViralRESUMO
Nitric oxide (NO) mediates fundamental physiological actions on skeletal muscle. The loss of NO synthase (NOS) from the sarcolemma was assumed to be associated with development of Duchenne muscular dystrophy (DMD). We have, however, recently reported that, in contrast to the commonly accepted view, NOS expression in DMD myofibres is up-regulated. This poses the question of the fibre type-specific NOS expression in DMD muscles and how the NOS expression is related to the regeneration or degeneration status. To address this issue, we examined localization of NOS isoforms I, II and III in skeletal muscles of DMD patients employing immunohistochemical labelling with tyramide signal amplification complemented with enzyme histochemistry. We found that NOS immunolabelling as well as metabolic enzyme activity in DMD muscles were heterogeneously distributed along the fibre length of DMD muscle fibres revealing regenerating and degenerate (hypercontracted) fibres as well as normal segments. Like in normal muscles, positive NOS immunoreactivity was found to be associated with fast-oxidative glycolytic (FOG) phenotype. The regeneration status of NOS-positive segments was deduced from the presence of neonatal and developmental myosin heavy chains. High NOS expression in regenerating DMD muscle fibres can be well reconciled with reports about the protective role of endogenous NO in inflammatory diseases and in muscle repair.
Assuntos
Fibras Musculares Esqueléticas/enzimologia , Músculo Esquelético/enzimologia , Distrofia Muscular de Duchenne/enzimologia , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Pré-Escolar , Humanos , Imuno-Histoquímica , Isoenzimas/metabolismo , Masculino , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/patologia , Cadeias Pesadas de Miosina/metabolismo , Regeneração/fisiologiaRESUMO
PURPOSE: A high serum level of beta human chorionic gonadotropin (hCG) normally indicates pregnancy in healthy women. We were confused by this finding in one of our patients. This 18-year-old girl presented with amenorrhoea of 1-month duration, a positive pregnancy test and a high beta-hCG serum level although taking contraceptives. Pregnancy was excluded by ultrasound. Three years previously, she had had an osteosarcoma of the humerus. The tumour initially had been wide resected and had shown a good response to neoadjuvant chemotherapy with COSS-96-protocol. METHODS: We reviewed the original histological result and the literature about possible similar findings. We analysed therapeutic options and the value of beta-hCG levels as a therapy monitor. RESULTS: During examination we detected a recurrent osteosarcoma of the left humerus. The local relapse evidently expressed beta-hCG which, retrospectively, could only sparsely be shown in the primary resectate. After intralesional surgery, chemotherapy and radiotherapy levels of beta-hCG normalised. CONCLUSION: Osteosarcoma very rarely is able to produce a paraneoplastic syndrome by high levels of beta-hCG. This may well be of diagnostic value and offer an additional monitoring tool. It can indicate tumour recurrence and dedifferentiation.
Assuntos
Biomarcadores Tumorais/sangue , Neoplasias Ósseas/diagnóstico , Gonadotropina Coriônica Humana Subunidade beta/sangue , Úmero/patologia , Recidiva Local de Neoplasia/diagnóstico , Osteossarcoma/diagnóstico , Testes de Gravidez , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/sangue , Neoplasias Ósseas/patologia , Neoplasias Ósseas/terapia , Quimioterapia Adjuvante , Diagnóstico Diferencial , Feminino , Humanos , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Osteossarcoma/sangue , Osteossarcoma/patologia , Osteossarcoma/terapia , Síndromes Paraneoplásicas/sangue , Síndromes Paraneoplásicas/diagnóstico , Gravidez , Radioterapia AdjuvanteRESUMO
Heterologous markers are important tools required for the molecular dissection of gene function in many organisms, including Saccharomyces cerevisiae. Moreover, the presence of gene families and isoenzymes often makes it necessary to delete more than one gene. We recently introduced a new and efficient gene disruption cassette for repeated use in budding yeast, which combines the heterologous dominant kan(r) resistance marker with a Cre/loxP-mediated marker removal procedure. Here we describe an additional set of four completely heterologous loxP-flanked marker cassettes carrying the genes URA3 and LEU2 from Kluyveromyces lactis, his5(+) from Schizosaccharomyces pombe and the dominant resistance marker ble(r) from the bacterial transposon Tn5, which confers resistance to the antibiotic phleomycin. All five loxP--marker gene--loxP gene disruption cassettes can be generated using the same pair of oligonucleotides and all can be used for gene disruption with high efficiency. For marker rescue we have created three additional Cre expression vectors carrying HIS3, TRP1 or ble(r) as the yeast selection marker. The set of disruption cassettes and Cre expression plasmids described here represents a significant further development of the marker rescue system, which is ideally suited to functional analysis of the yeast genome.
Assuntos
Aldose-Cetose Isomerases , Proteínas de Bactérias , Deleção de Genes , Integrases/metabolismo , Mutagênese Insercional/métodos , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Proteínas Virais/metabolismo , 3-Isopropilmalato Desidrogenase , Acetiltransferases/genética , Oxirredutases do Álcool/genética , Sequência de Bases , Proteínas Fúngicas/genética , Marcadores Genéticos , Hidroliases/genética , Resistência a Canamicina , Modelos Genéticos , Dados de Sequência Molecular , Oligonucleotídeos/genética , Organismos Geneticamente Modificados , Plasmídeos , Transformação GenéticaRESUMO
OBJECTIVE: To evaluate systematically the effectiveness of six advertising strategies (two message strategies presented in three different contexts) designed to promote smoking cessation by addressing smokers' misperceptions about Light cigarettes. DESIGN: Smokers viewed one of six, 30 second test television concept advertisements, which varied by message (one emphasising how the sensory effects of Lights can be deceptive, the other describing the effects of vent blocking) and by ad context (non-commercial public service announcement (PSA), promotion of unbranded nicotine replacement therapy (NRT), or promotion of branded NRT). The effectiveness of each advertisement was determined using a validated advertising testing system in which ads were viewed in the context of reviewing a pilot television programme. Response to ads is assessed through shifts in subject choices of products offered as prizes before and after viewing the test advertisements. Included among the possible prizes were cigarettes and various pharmacotherapies for smoking cessation. SUBJECTS: Daily smokers (n = 1890) of Regular (34%), Light (47%), and Ultra Light (19%) cigarettes recruited from eight US cities. MAIN OUTCOMES MEASURES: The primary outcome of interest was the shift away from cigarettes as the selected prize following exposure to the test advertisements. Secondary outcomes of interest included movement away from Light cigarettes and movement towards assisted quitting products. RESULTS: Smokers who saw the advertisement emphasising the sensory characteristics of Light cigarettes were more likely than subjects who saw the advertisement emphasising the effect of vent blocking to move away from cigarettes (OR = 1.97, 95% confidence interval CI 1.25 to 3.09; chi(2)(1) = 8.69, p = 0.003). Similarly, subjects who saw the advertisement framed as a PSA, rather than as a promotion for either a branded or unbranded NRT product, were also somewhat more likely to move away from cigarettes (OR = 1.51, 95% CI 0.94 to 2.40; chi(2)(1) = 2.97, p = 0.085). The effect was observed regardless of sex, age, or type of cigarette smoked. CONCLUSIONS: Addressing smokers' sensory perceptions of Light cigarettes and presenting this information in an impartial way is likely to be an effective communication strategy for counter-marketing Light cigarettes.
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Publicidade/métodos , Projetos de Pesquisa/estatística & dados numéricos , Abandono do Uso de Tabaco/psicologia , Adulto , Publicidade/tendências , Feminino , Humanos , Masculino , Nicotina/análise , Avaliação de Processos e Resultados em Cuidados de Saúde , Percepção , Fumaça/análise , Alcatrões/análise , NicotianaRESUMO
PURPOSE: To evaluate fluorine 18 (18F) dopa positron emission tomography (PET) in comparison with established imaging procedures in gastrointestinal carcinoid tumors. MATERIALS AND METHODS: After evaluation of the normal distribution of 18F dopa, 17 patients with histologically confirmed tumors were examined with 18F dopa PET. Results of 2-[fluorine 18]fluoro-2-deoxy-D-glucose (FDG) PET, somatostatin-receptor scintigraphy, and morphologic imaging (computed tomography and/or magnetic resonance imaging) were available for all patients. Results of the procedures were evaluated by two radiologists and two nuclear medicine specialists, whose consensus based on all available histologic, imaging, and follow-up findings was used as the reference standard. RESULTS: Ninety-two tumors were diagnosed: eight primary tumors, 47 lymph node metastases, and 37 organ metastases. 18F dopa PET led to 60 true-positive findings (seven primary tumors, 41 lymph node metastases, 12 organ metastases); FDG PET, 27 (two primary tumors, 14 lymph node metastases, 11 organ metastases); somatostatin-receptor scintigraphy, 52 (four primary tumors, 27 lymph node metastases, 21 organ metastases); and morphologic imaging, 67 (two primary tumors, 29 lymph node metastases, 36 organ metastases). This resulted in the following overall sensitivities: 18F dopa PET, 65% (60 of 92); FDG PET, 29% (27 of 92); somatostatin-receptor scintigraphy, 57% (52 of 92); morphologic procedures, 73% (67 of 92). Although the morphologic procedures were most sensitive for organ metastases, 18F dopa PET enabled best localization of primary tumors and lymph node staging. CONCLUSION: 18F dopa PET is a promising procedure and useful supplement to morphologic methods in diagnostic imaging of gastrointestinal carcinoid tumors.
Assuntos
Tumor Carcinoide/diagnóstico por imagem , Di-Hidroxifenilalanina , Radioisótopos de Flúor , Neoplasias Gastrointestinais/diagnóstico por imagem , Tomografia Computadorizada de Emissão , Adulto , Idoso , Feminino , Fluordesoxiglucose F18 , Humanos , Metástase Linfática/diagnóstico , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Receptores de Somatostatina , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios XRESUMO
The stable-oxygen and -hydrogen isotopic values (deltaD, delta18O) of porewater in geologic media are commonly determined on water obtained by extraction techniques such as centrifugation, mechanical squeezing, vacuum heating and cryogenic microdistillation, and azeotropic distillation. Each of these techniques may cause isotopic fractionation as part the extraction process and each is laborious. Here we demonstrate a new approach to obtain automated, high-precision deltaD and delta18O measurements of porewater in geologic sediments by direct H2- and CO2-porewater equilibration using a modified commercial CO2-water equilibrator. This technique provides an important and cost-effective improvement over current extraction methods, because many samples can be rapidly analyzed with minimal handling, thereby reducing errors and potential for isotopic fractionation. The precision and accuracy of direct H2- and CO2-porewater equilibration is comparable to or better than current porewater extraction methods. Finally, the direct equilibration technique allows investigators to obtain high-resolution (cm scale) porewater deltaD and delta18O profiles using cores from individual boreholes, eliminating the need for costly piezometers or conventional porewater extractions.
RESUMO
This study examined the effects of Critical Incident Stress Debriefing (CISD) upon technicians who provided emergency medical services in South Central Los Angeles during the 1992 Los Angeles Civil Disturbance. The relationships between exposure, debriefing and symptoms of stress were identified and examined. The Frederick Reaction Index-Adult (FRI-A) was used to measure the presence of symptoms characteristic of posttraumatic stress disorder. EMTs who had the opportunity to participate in Critical Incident Stress Debriefings (n = 42) following the incident reported fewer symptoms and scored significantly lower on the FRI-A than those not participating in Critical Incident Stress Debriefing (n = 23).
Assuntos
Intervenção em Crise , Auxiliares de Emergência/psicologia , Doenças Profissionais/prevenção & controle , Tumultos , Estresse Psicológico/prevenção & controle , Humanos , Los AngelesRESUMO
Few studies have used the stable isotopic composition of O(2) as a tracer of gas transport or biogeochemical processes in environmental research. Here we demonstrate field sampling techniques for gaseous and dissolved O(2) and describe an analytical method for measuring δ(18)O and δ(17)O values of O(2) in air, soil gas, and water samples using continuous-flow isotope-ratio mass spectrometry (CF-IRMS). A Micromass CF-IRMS was altered to accommodate a sample gas injection port prior to a CO(2) and H(2)O trap and GC column. The GC column was a 1-m, 5-Å molecular sieve column held at 35 °C. The resolved sample O(2) was introduced to the IRMS via an open split. δ(18)O and δ(17)O values were determined by measurement of O(2) isotopes at m/z 34/32 and 33/32 and comparison to a reference pulse of O(2). Repeated injections of atmospheric oxygen yielded a repeatability (±SD) of ±0.17 for δ(18)O and ±0.5 for δ(17)O. IRMS source linearity was excellent for O(2) over a sample size range of 60-400 µL. The smallest sample for routine δ(18)O and δ(17)O determinations was â¼80 µL of O(2), with a sample analysis time of 180 s. Preliminary results from a riverine and soil gas study illustrate natural oxygen isotope fractionation processes.
RESUMO
The purpose of comparative pathology is to develop a fuller understanding of pathologic processes in individuals of various species. Historically, we distinguish between direct and indirect findings. Direct sources are paleopathologic fossils. Indirect findings are historic and/or religious descriptions of epidemics. The philosophy behind the comparative approach depends primarily on the individuals of the species as units. The individual represents a concrete reality, whereas the other taxonomic categories are only theoretical entities contrived by human thought. Intraspecies-specific comparison and the interspecies-specific comparison are distinguishable. In intraspecies-specific comparison different individuals (races, breeds) of one species are compared, whereas in the interspecies-specific comparison individuals of several species are compared. Evolution and the comparative ontogenetic development of recent organisms explains how the variability of species came into existence. Consistency in evolution and uniformity is given by the fact that members of all phyla are still represented by some remaining species. Heterogeneity of organismic structures are more numerous but secondary. With the exception of the virus, the cell is remaining the unit of living matter, but viruses depend on cells for their existence. The majority of species, the eumetazoans and vascular plants, are built of true tissues developed by cell division, whereas higher fungi and some algae exhibit plectenchymata which develop by the fusion of cells. This short article presents some thoughts and principles underlining the importance of development of guideline for the study of comparative pathology.
Assuntos
Histologia Comparada/métodos , Patologia/métodos , Animais , Doença/classificação , Ecologia , HumanosRESUMO
We describe methods for the preservation, extraction and amplification of DNA from faeces that facilitate field applications of faecal DNA technology. Mitochondrial, protein encoding and microsatellite nuclear DNA extracted and amplified from faeces of Malayan sun bears and North American black bears is shown to be identical to that extracted and amplified from the same individual's tissue or blood. A simple drying agent, silica beads, is shown to be a particularly effective preservative, allowing easy and safe transport of samples from the field. Methods are also developed to eliminate the risk of faecal DNA contamination from hair present in faeces.
Assuntos
DNA/análise , Fezes/química , Técnicas Genéticas , Animais , Bioquímica/métodos , DNA/sangue , DNA/química , DNA Mitocondrial/análise , Feminino , Cabelo , Masculino , Reação em Cadeia da Polimerase/métodos , Processos de Determinação Sexual , Manejo de Espécimes/métodos , Ursidae/genéticaRESUMO
The development of blood cells from hematopoietic stem cells is controlled by multiple cytokines. These growth factors influence survival, cell cycle status, differentiation into lineage-committed progenitors, final maturation into blood cells, and perhaps self-renewal of stem cells. The specific contribution of IL-6 to these processes in vivo was evaluated in mice with a targeted disruption of the IL-6 gene. Decreases in the absolute numbers of CFU-Sd12 and preCFU-S, as well as in the functionality of LTRSC in these mutant mice, suggests a role for IL-6 in the survival, self-renewal, or both of hematopoietic stem cells and early progenitors. In addition, as a result of the IL-6 deficiency, the control between proliferation and differentiation of the progenitor cells of the granulocytic-monocytic, megakaryocytic, and erythroid lineages into mature blood cells is altered, leading to abnormal levels of committed progenitors of these lineages and to a slow recovery from hematopoietic ablation.
Assuntos
Hematopoese , Células-Tronco Hematopoéticas/fisiologia , Interleucina-6/deficiência , Células-Tronco/fisiologia , Animais , Sequência de Bases , Medula Óssea/metabolismo , Células da Medula Óssea , Diferenciação Celular , Divisão Celular , Sobrevivência Celular , Interleucina-6/fisiologia , Camundongos , Dados de Sequência Molecular , Baço/citologia , Baço/metabolismoRESUMO
In mice with targeted disruption of the gene that encodes interleukin-6 (IL-6), greatly reduced numbers of immunoglobulin A (IgA)-producing cells were observed at mucosae and grossly deficient local antibody responses were recorded after mucosal challenge with either ovalbumin or vaccinia virus. The IgA response in the lungs was completely restored after intranasal infection with recombinant vaccinia viruses engineered to express IL-6. These findings demonstrate a critical role for IL-6 in vivo in the development of local IgA antibody responses and illustrate the effectiveness of vector-directed cytokine gene therapy.