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Ceramic capillary membranes conditioned for virus filtration via functionalization with n-(3-trimethoxysilylpropyl)diethylenetriamine (TPDA) are analyzed with respect to their virus retention capacity when using feed solutions based on monovalent and divalent salts (NaCl, MgCl2). The log reduction value (LRV) by operating in dead-end mode using the model bacteriophage MS2 with a diameter of 25 nm and an IEP of 3.9 is as high as 9.6 when using feeds containing MgCl2. In contrast, a lesser LRV of 6.4 is observed for feed solutions based on NaCl. The TPDA functionalized surface is simulated at the atomistic scale using explicit-solvent molecular dynamics in the presence of either Na+ or Mg2+ ions. Computational prediction of the binding free energy reveals that the Mg2+ ions remain preferentially adsorbed at the surface, whereas Na+ ions form a weakly bound dissolved ionic layer. The charge shielding between surface and amino groups by the adsorbed Mg2+ ions leads to an upright orientation of the TPDA molecules as opposed to a more tilted orientation in the presence of Na+ ions. The resulting better accessibility of the TPDA molecules is very likely responsible for the enhanced virus retention capacity using a feed solution with Mg2+ ions.
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The presence of high concentrations of hydrogen sulfide in the sewer system can result in corrosion of the concrete sewer pipes. The formation and fate of hydrogen sulfide in the sewer system is governed by a complex system of biological, chemical and physical processes. Therefore, mechanistic models have been developed to describe the underlying processes. In this work, global sensitivity analysis was applied to an in-sewer process model (aqua3S) to determine the most important model input factors with regard to sulfide formation in rising mains and the concrete corrosion rate downstream of a rising main. The results of the sensitivity analysis revealed the most influential model parameters, but also the importance of the characteristics of the organic matter, the alkalinity of the concrete and the movement of the sewer gas phase.
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Drenagem Sanitária , Modelos Teóricos , Sulfetos/química , CorrosãoRESUMO
BACKGROUND: Cyclin-dependent kinases (CDKs) control cell cycle progression, RNA transcription and apoptosis, making them attractive targets for anticancer drug development. Unfortunately, CDK inhibitors developed to date have demonstrated variable efficacy. METHODS: We generated drug-resistant cells by continuous low-dose exposure to a model pyrazolo[1,5-a]pyrimidine CDK inhibitor and investigated potential structural alterations for optimal efficacy. RESULTS: We identified induction of the ATP-binding cassette (ABC) transporters, ABCB1 and ABCG2, in resistant cells. Assessment of features involved in the ABC transporter substrate specificity from a compound library revealed high polar surface area (>100 Å(2)) as a key determinant of transporter interaction. We developed ICEC-0782 that preferentially inhibited CDK2, CDK7 and CDK9 in the nanomolar range. The compound inhibited phosphorylation of CDK substrates and downregulated the short-lived proteins, Mcl-1 and cyclin D1. ICEC-0782 induced G2/M arrest and apoptosis. The permeability and cytotoxicity of ICEC-0782 were unaffected by ABC transporter expression. Following daily oral dosing, the compound inhibited growth of human colon HCT-116 and human breast MCF7 tumour xenografts in vivo by 84% and 94%, respectively. CONCLUSION: We identified a promising pyrazolo[1,5-a]pyrimidine compound devoid of ABC transporter interaction, highly suitable for further preclinical and clinical evaluation for the treatment of cancer.
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Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Quinases Ciclina-Dependentes/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/genética , Divisão Celular/efeitos dos fármacos , Divisão Celular/genética , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/genética , Ciclina D1/genética , Quinases Ciclina-Dependentes/metabolismo , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Feminino , Fase G2/efeitos dos fármacos , Fase G2/genética , Células HCT116 , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteínas de Neoplasias/genética , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacocinética , Pirimidinas/farmacocinética , Pirimidinas/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The paradigm shift in recent years towards sustainable and coherent water resources management on a river basin scale has changed the subject of investigations to a multi-scale problem representing a great challenge for all actors participating in the management process. In this regard, planning engineers often face an inherent conflict to provide reliable decision support for complex questions with a minimum of effort. This trend inevitably increases the risk to base decisions upon uncertain and unverified conclusions. This paper proposes an adaptive framework for integral planning that combines several concepts (flow balancing, water quality monitoring, process modelling, multi-objective assessment) to systematically evaluate management strategies for water quality improvement. As key element, an S/P matrix is introduced to structure the differentiation of relevant 'pressures' in affected regions, i.e. 'spatial units', which helps in handling complexity. The framework is applied to a small, but typical, catchment in Flanders, Belgium. The application to the real-life case shows: (1) the proposed approach is adaptive, covers problems of different spatial and temporal scale, efficiently reduces complexity and finally leads to a transparent solution; and (2) water quality and emission-based performance evaluation must be done jointly as an emission-based performance improvement does not necessarily lead to an improved water quality status, and an assessment solely focusing on water quality criteria may mask non-compliance with emission-based standards. Recommendations derived from the theoretical analysis have been put into practice.
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Meio Ambiente , Qualidade da Água , Recursos Hídricos , Bélgica , Pressão , Esgotos/químicaRESUMO
While opioid addiction has reached pandemic proportions, we still lack a good understanding of how the administration of opioids interacts with cognitive functions. Error processing - the ability to detect erroneous actions and correct one's behaviour afterwards - is one such cognitive function that might be susceptible to opioidergic influences. Errors are hypothesised to induce aversive negative arousal, while opioids have been suggested to reduce aversive arousal induced by unpleasant and stressful stimuli. Thus, this study investigated whether the acute administration of an opioid would affect error processing. In a double-blind between-subject study, 42 male volunteers were recruited and received either 0.2 mg buprenorphine (a partial µ-opioid receptor agonist and κ-opioid receptor antagonist) or a placebo pill before they performed a stimulus-response task provoking errors. Electroencephalograms (EEG) were recorded while participants performed the task. We observed no group differences in terms of reaction times, error rates, and affective state ratings during the task between buprenorphine and control participants. Additional measures of adaptive control, however, showed interfering effects of buprenorphine administration. On the neural level, decreased Pe (Error Positivity) amplitudes were found in buprenorphine compared to control participants following error commission. Further, frontal delta oscillations were decreased in the buprenorphine group after all responses. Our neural results jointly demonstrate a general reduction in error processing in those participants who received an opioid before task completion, thereby suggesting that opioids might have indeed the potential to dampen motivational error signals. Importantly, the effects of the opioid were evident in more elaborate error processing stages, thereby impacting on processes of conscious error appraisal and evidence accumulation.
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Analgésicos Opioides/farmacologia , Buprenorfina/administração & dosagem , Buprenorfina/farmacologia , Motivação/efeitos dos fármacos , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/efeitos adversos , Buprenorfina/efeitos adversos , Ritmo Delta/efeitos dos fármacos , Eletroencefalografia , Humanos , Masculino , Antagonistas de Entorpecentes/administração & dosagem , Antagonistas de Entorpecentes/farmacologia , Adulto JovemRESUMO
We demonstrate experimentally an efficient coherent rephasing scheme for the storage and recall of weak coherent light pulses in an inhomogeneously broadened optical transition in a Pr(3+):YSO crystal at 2.1 K. Precise optical pumping using a frequency stable (≈1 kHz linewidth) laser is employed to create a highly controllable atomic frequency comb structure. We report single photon level storage and retrieval efficiencies of 25%, based on coherent photon-echo-type reemission in the forward direction. The high efficiency is mainly a product of our highly controllable and precise ensemble-shaping technique. The coherence property of the quantum memory is proved through interference between a super-Gaussian pulse and the emitted echo.
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BACKGROUND AND PURPOSE: Mycotic keratitis is a serious but relatively rare disease. No targeted data collection in Germany existed until the foundation of the German Pilz-Keratitis Register in 2015. PATIENTS AND METHODS: The inclusion of retrospective and prospective patients was carried out. INCLUSION CRITERIA: diagnosis confirmed by the polymerase chain reaction (PCR), culture, histology or confocal microscopy (IVCM). Collected parameters: date of symptom onset, date and method of diagnosis, risk factors, visual acuity and findings at admission and at follow-up, conservative and surgical treatment. RESULTS: By January 2018, a total of 102 eyes from the years 2000-2017 were reported from 16 centers (64.3% female, mean age 52 years, range 18-95 years). The initial diagnosis was made correctly in only 20.6% of cases. The mean time to correct diagnosis was 31.7⯱â¯46.9 (0-296) days. The diagnosis was confirmed in cultures in 74.5%, histologically in 30.4%, by PCR in 38.2% and IVCM in 27.4%. Fungal species identified were: 36.7% Fusarium spp., 35.8% Candida spp., 6.4% Aspergillus spp. and 21.1% other. The most important risk factor was the use of contact lenses. The most commonly used antifungal agent was voriconazole (64.7%) followed by amphotericin B (37.2%). Penetrating keratoplasty was performed in 65.7% of the cases and 8.8% of the affected eyes had to be enucleated. The visual acuity of the entire study population increased from the initial 0.16⯱â¯0.25 (0.001-1.0) decimal to 0.28⯱â¯0.34 (0-1.0) decimal. CONCLUSION: The correct diagnosis of fungal keratitis is often significantly delayed. The treatment can be very difficult and keratoplasty is often necessary. In order to gain a better understanding of this disease, to recognize previously unknown risk factors and, if necessary, a change in the spectrum of pathogens and to identify approaches to treatment optimization, the fungal keratitis registry will be continued.
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Infecções Oculares Fúngicas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antifúngicos , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros , Estudos Retrospectivos , Inquéritos e Questionários , Adulto JovemRESUMO
There have recently been several studies of the performance of laser frequency stabilization using spectral holes in solids, instead of an external cavity, as a frequency reference. Here an analytical theory for Pound-Drever-Hall laser frequency stabilization using spectral hole-burning is developed. The interaction between the atomic medium and the phase modulated light is described using a linearized model of the Maxwell-Bloch equations. The interplay between the carrier and modulation sidebands reveals significant differences from the case of locking to a cavity. These include a different optimum modulation index, an optimum sample absorption, and the possibility to lock the laser in an inherent linear frequency drift mode. Spectral holes in solids can be permanent or transient. For the materials normally used, the dynamics and time scales of transient holes often depend on population relaxation processes between ground state hyperfine levels. These relaxation rates can be very different for different solid state materials. We demonstrate, using radio-frequency pumping, that the hyperfine population dynamics may be controlled and tailored to give optimum frequency stabilization performance. In this way also materials with initially non-optimum performance can be used for stabilization. The theoretical predictions regarding the inherent linear frequency drift is compared to experimental data from a dye laser stabilized to a spectral hole in a Pr(3+)3+:Y(2)SiO(5) crystal.
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The detection of contamination such as salt in outdoor high-voltage insulator systems and its subsequent removal are vital for a reliable transmission of electric power. Remote detection of salt on a copper metal surface was carried out by using a mobile laser-induced breakdown spectroscopy (LIBS) Lidar system with a laser wavelength of 355 nm. Detection of salt on a polymeric high-voltage insulator was obtained when an additional lens was inserted into the beam path, and the number of photons that was detected could be calculated by using a calibrated white light source. Ablative cleaning could readily be carried out with LIBS and was verified by observing the disappearance of the sodium D-line emission.
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Genomic instability appears to play an important role in the development, growth, invasiveness, and eventual metastasis of the neoplastic cell. We have used a powerful new technique, comparative genomic hybridization, to evaluate genetic alterations in 10 fresh frozen uveal melanomas. Comparative genomic hybridization utilizes dual fluorescence in situ hybridization to characterize chromosome deletions and duplications, allowing for simultaneous evaluation of the entire human genome. Several consistent chromosomal abnormalities were detected. This study confirmed previous findings obtained using standard cytogenetic techniques but demonstrated an increased incidence in abnormalities of chromosomes 3 and 8; there was loss of chromosome 3 and duplication of 8q. In addition, we identified, although less frequently, other recurrent abnormal regions including alterations on chromosomes 6p, 7q, 9p, and 13q.
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Aberrações Cromossômicas/genética , DNA de Neoplasias/genética , Hibridização in Situ Fluorescente/métodos , Melanoma/genética , Neoplasias Uveais/genética , HumanosRESUMO
PURPOSE: To identify factors associated with radiation pneumonitis (RP) resulting from combined modality therapy (CMT) for lung cancer. MATERIALS AND METHODS: Series published before 1994 that used CMT for the treatment of lung cancer and explicitly reported the incidence of RP are the basis for this analysis. Factors evaluated included the radiation dose per fraction (Fx), total radiation dose, fractionation scheme (split v continuous), type of chemotherapy and intended dose-intensity, overall treatment time, histology (small-cell lung cancer [SCLC] v non-small-cell lung cancer [NSCLC]), and treatment schedule (concurrent v induction, sequential, or alternating CMT). RESULTS: Twenty-four series, including 27 treatment groups and 1,911 assessable patients, met our criteria for inclusion in this analysis. The median total dose of radiation used in the trials analyzed was 50 Gy (range, 25 to 63 Gy). The median daily Fx used was 2.0 Gy (range, 1.5 to 4.0 Gy). Nineteen series included 22 treatment groups and 1,745 patients treated with single daily fractions. Among these patients, 136 received a daily Fx greater than 2.67 Gy. Five series used twice-daily radiotherapy and included 166 patients (Fx, 1.5 to 1.7 Gy). The incidence of RP was 7.8%. In a multivariate analysis, only daily Fx, number of daily fractions, and total dose were associated with the risk of RP (P < .0001, P < .018, and P < .003, respectively). CONCLUSION: In this analysis, the use of Fx greater than 2.67 Gy was the most significant factor associated with an increased risk of RP. High total dose also appears to be associated with an increased risk, but twice-daily irradiation seems to reduce the risk expected if the same total daily dose is given as a single fraction. High-Fx radiotherapy should be avoided in patients who receive CMT with curative intent.
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Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma de Células Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Pneumonite por Radiação/etiologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma de Células Pequenas/tratamento farmacológico , Distribuição de Qui-Quadrado , Terapia Combinada/efeitos adversos , Relação Dose-Resposta à Radiação , Humanos , Incidência , Modelos Logísticos , Neoplasias Pulmonares/tratamento farmacológico , Análise Multivariada , Prognóstico , Pneumonite por Radiação/epidemiologia , Pneumonite por Radiação/prevenção & controle , Fatores de RiscoRESUMO
PURPOSE: To evaluate the efficacy and safety of tositumomab and iodine I 131 tositumomab (Bexxar; Corixa Corp, Seattle, WA, and GlaxoSmithKline, Philadelphia, PA) in patients with chemotherapy-refractory low-grade or transformed low-grade non-Hodgkin's lymphoma (NHL) and to compare its efficacy to the patients' last qualifying chemotherapy (LQC) regimens. PATIENTS AND METHODS: Sixty patients who had been treated with at least two protocol-specified qualifying chemotherapy regimens and had not responded or progressed within 6 months after their LQC were treated with a single course of iodine I 131 tositumomab. RESULTS: Patients had received a median of four prior chemotherapy regimens. A partial or complete response (CR) was observed in 39 patients (65%) after iodine I 131 tositumomab, compared with 17 patients (28%) after their LQC (P <.001). The median duration of response (MDR) was 6.5 months after iodine I 131 tositumomab, compared with 3.4 months after the LQC (P <.001). Two patients (3%) had a CR after their LQC, compared with 12 (20%) after iodine I 131 tositumomab (P <.001). The MDR for CR was 6.1 months after the LQC and had not been reached with follow-up of more than 47 months after iodine I 131 tositumomab. An independent review panel verified that 32 (74%) of the 43 patients with nonequivalent durations of response (> 30 days difference) had a longer duration of response after iodine I 131 tositumomab (P <.001). Only one patient was hospitalized for neutropenic fever. Five patients (8%) developed human antimurine antibodies, and one (2%) developed an elevated TSH level after treatment. Myelodysplasia was diagnosed in four patients in follow-up. CONCLUSION: A single course of iodine I 131 tositumomab was significantly more efficacious than the LQC received by extensively pretreated patients with chemotherapy-refractory, low-grade, or transformed low-grade NHL and had an acceptable safety profile.
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Anticorpos Monoclonais/uso terapêutico , Radioisótopos do Iodo/uso terapêutico , Linfoma de Células B/radioterapia , Linfoma não Hodgkin/radioterapia , Adulto , Idoso , Anticorpos Monoclonais/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Radioisótopos do Iodo/efeitos adversos , Linfoma de Células B/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Masculino , Pessoa de Meia-IdadeRESUMO
PURPOSE: An open-label phase II study was conducted at two centers to establish the efficacy and safety of tositumomab and iodine I 131 tositumomab at first or second recurrence of indolent or transformed indolent B-cell lymphoma. PATIENTS AND METHODS: A single dosimetric dose was followed at 7 to 14 days by the patient-specific administered radioactivity required to deliver a total body dose of 0.75 Gy (reduced to 0.65 Gy for patients with platelets counts of 100 to 149 x 10(9)/L). Forty of 41 patients received both infusions. RESULTS: Thirty-one of 41 patients (76%) responded, with 20 patients (49%) achieving either a complete (CR) or unconfirmed complete remission [CR(u)] and 11 patients (27%) achieving a partial remission. Response rates were similar in both indolent (76%) and transformed disease (71%). The overall median duration of remission was 1.3 years. The median duration of remission has not yet been reached for those patients who achieved a CR or CR(u). Eleven patients continue in CR or CR(u) between 2.6+ and 5.2+ years after therapy. Therapy was well tolerated; hematologic toxicity was the principal adverse event. Grade 3 or 4 anemia, neutropenia, and thrombocytopenia were observed in 5%, 45%, and 32% of patients, respectively. Secondary myelodysplasia has occurred in one patient. Four patients developed human antimouse antibodies after therapy. Five of 38 assessable patients have developed an elevated thyroid-stimulating hormone; treatment with thyroxine has been initiated in one patient. CONCLUSION: High overall and CR rates were observed after a single dose of tositumomab and iodine I 131 tositumomab in this patient group. Toxicity was modest and easily managed.
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Anticorpos Monoclonais/uso terapêutico , Antígenos CD20/imunologia , Imunoconjugados/uso terapêutico , Linfoma de Células B/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Antineoplásicos , Humanos , Radioisótopos do Iodo/uso terapêutico , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Radioimunoterapia , Taxa de SobrevidaRESUMO
BACKGROUND: Iron is an essential micronutrient but also a major catalyst of oxidative and inflammatory reactions. OBJECTIVE: To evaluate the potential utility of selected biomarkers in blood or urine to indicate in vivo oxidative or inflammatory response to oral iron intake at pharmacological doses. METHODS: Three healthy volunteers provided morning, fasting samples of blood and urine on up to 13 study days--3 before, 7 during and 3 following a 7-consecutive-day period of receiving 120 mg of iron per day as ferrous sulfate in commercially available syrup. A series of 23 biomarkers were measured on each collection of biological fluids to monitor iron-responsive changes in biomarkers related to hematological or iron status, inflammation and in vivo oxidation. RESULTS: Among the inflammatory biomarkers measured, white blood cells, serum CRP and urinary neopterin showed no response to iron dosing. Only circulating interleukin-4 (IL-4) and TNF-alpha had abnormal responses with a time association to the oral iron intake. Among the oxidative biomarkers, expression of blood superoxide dismutase (SOD), hemoxygenase-1, catalase as well as circulating thiobarbituric acid reactive substances (TBARS), total oxidative capacity and carbonyl proteins were stable in response to iron exposure. Only urinary TBARS, 8-hydroxy-2-desoxyguanosine and isoprostanes evidenced consistent or suggestive responses to ingestion of the iron challenge. Serum hepcidin concentration increased dramatically in all three subjects after only the first 120 mg dose of iron, and remained elevated even 9 days after cessation of the iron intervention. CONCLUSIONS: Most of the candidate biomarkers show very limited promise as response-indicators to oral iron dosing at the 120 mg dosages or lower, but circulating IL-4, TNF-alpha as well as urinary TBARS, 8-hydroxy-2-desoxyguanosine and isoprostanes showed potential utility as reliable indicators of oxidative and inflammatory response to oral ferrous sulfate.
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Compostos Ferrosos/toxicidade , Inflamação/sangue , Inflamação/induzido quimicamente , Estresse Oxidativo/efeitos dos fármacos , Administração Oral , Adulto , Biomarcadores/sangue , Biomarcadores/urina , Feminino , Testes Hematológicos/métodos , Humanos , Inflamação/urina , Masculino , Estresse Oxidativo/fisiologia , Projetos PilotoRESUMO
Uveal melanoma cell cycling, quantified by bromodeoxyuridine (BrdUrd)-labeling index and mitotic index, is predictive of tumor-related mortality. Serial sections from 36 formalin-fixed melanoma specimens were labeled with BrdUrd and stained with hematoxylin and eosin. All tumors were assessed for the area of highest cell cycling activity and counts for mitotic figures and BrdUrd labeling were performed in these areas in a masked manner. The BrdUrd labeling index and mitotic index were calculated and analyzed in relation to tumor-related mortality and histopathological criteria (largest tumor diameter, cell type, extra-scleral extension, ocular location). Cox multivariate analysis estimated an increased relative risk of tumor-related mortality of 2. 32 (95% confidence interval, 1.22-4.41) per doubling of BrdUrd labeling index and 2.41 (95% confidence interval, 1.29-4.49) per doubling mitotic index. Larger tumors, nonspindle cell tumors, and anterior-located tumors tended to have higher cycling rates.
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Ciclo Celular , Melanoma/patologia , Índice Mitótico , Neoplasias Uveais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bromodesoxiuridina , Amarelo de Eosina-(YS) , Hematoxilina , Humanos , Melanoma/mortalidade , Melanoma/cirurgia , Pessoa de Meia-Idade , Análise Multivariada , Metástase Neoplásica , Prognóstico , Análise de Regressão , Análise de Sobrevida , Fatores de Tempo , Neoplasias Uveais/mortalidade , Neoplasias Uveais/cirurgiaRESUMO
A method combining laser-induced fluorescence and principal component analysis to detect and discriminate between algal and fungal growth on insulator materials has been studied. Eight fungal cultures and four insulator materials have been analyzed. Multivariate classifications were utilized to characterize the insulator material, and fungal growth could readily be distinguished from a clean surface. The results of the principal component analyses make it possible to distinguish between algae infected, fungi infected, and clean silicone rubber materials. The experiments were performed in the laboratory using a fiber-optic fluorosensor that consisted of a nitrogen laser and an optical multi-channel analyzer system.
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Contaminação de Equipamentos , Fungos/química , Fungos/isolamento & purificação , Análise de Componente Principal , Elastômeros de Silicone/química , Eucariotos/química , Eucariotos/isolamento & purificação , Lasers , Nitrogênio/química , Espectrometria de Fluorescência , Esporos Fúngicos/química , Esporos Fúngicos/isolamento & purificação , Sri Lanka , Suécia , TanzâniaRESUMO
We develop a statistical approach for the study of S phase duration in experiments using sequential pulses of two thymidine analogues. Cell entrance into S phase is assumed to follow a possibly nonhomogeneous Poisson process, and the duration in S phase independently follows an unspecified distribution, thus allowing the possibility of variable S phase duration times for cells. Several conclusions regarding experimental design considerations are reached. The availability of three labelled cell subgroups comprising cells receiving exactly one of the two thymidine analogues or receiving both thymidine analogues at least doubles the efficiency of the mean S phase duration estimate compared to conventional estimates based on two labelled groups. Increasing the duration between the two thymidine analogue pulses can also dramatically increase the efficiency. The modelling technique was applied to fourteen uveal melanomas from patients who received in vivo injections of two thymidine analogues, bromodeoxyuridine (BrdUrd) and iododeoxyuridine (IdUrd). Counts of labelled cells were consistent with steady-state time homogeneous entry into S phase and nonhomogeneous spatial entry into S phase.
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Fase S , Biomarcadores , Bromodesoxiuridina , Neoplasias da Coroide/patologia , Humanos , Idoxuridina , Melanoma/patologia , Processos EstocásticosRESUMO
Eleven patients with subcutaneous prosthetic breast implants were followed 3-16 years after mammary irradiation. Radiation doses ranged between 45 Gy and 50 Gy to the whole breast, supplemented in five cases with 10-21 Gy scar boost. Evaluation of the cosmetic results revealed a good score in three patients, moderate to fair in three, and poor in five. Of the five patients who had poor postirradiation cosmesis, three had fibrotic changes and encapsulation of the prostheses prior to the irradiation, and two received their irradiation 1 month after the reconstruction. In most of the patients, the nonirradiated breast was augmented with a prosthesis and both breasts could be followed for comparison. The irradiated side usually looked and felt on palpation worse than the nonirradiated, but both breasts exhibited a steady deterioration in appearance over time. The patients who enjoyed better cosmetic results after irradiation had better breast appearance before the radiotherapy. Of three patients treated with lower doses (45 Gy/4.5-5 weeks), two enjoyed good cosmesis. Both patients who received irradiation immediately after reconstructive surgery had poor cosmetic results. Three observations could be made: (a) when the implanted breast was free of fibrotic changes, radiotherapy produced acceptable results, (b) whenever feasible, 45 Gy/5 weeks seemed preferable over higher doses, (c) irradiation immediately after the reconstructive surgery appeared to produce poorer cosmetic results.
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Neoplasias da Mama/radioterapia , Mama/cirurgia , Próteses e Implantes , Adulto , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos RetrospectivosRESUMO
PURPOSE: Episcleral 125I plaque therapy of uveal melanoma is an important treatment modality to control tumor, salvage the globe, and potentially preserve vision. We retrospectively analyzed our experience in 239 patients to assess treatment outcome with this technique. METHODS AND MATERIALS: Between 1983 and 1990, 239 uveal melanoma patients were treated with 125I plaques at the University of California, San Francisco. High intensity 125I seeds in the range of 3-20 mCi were used to give a minimum tumor dose of 70 Gy in 4 days. Initial mean tumor size was 10.9 mm x 9.2 mm x 5.5 mm with a range in tumor diameter from 4 to 18 mm and tumor height from 1.9 to 11.1 mm. Best corrected pre-treatment visual acuity was 20/200 or better in 92% of patients. RESULTS: Local tumor control was maintained in 91.7% of patients with a mean follow-up of 35.9 months; 19 patients had local tumor progression; mean time to progression was 27.3 mo (1.8 to 60.1 mo). Actuarial local control is 82% at 5 years. Multivariate analysis demonstrates significant correlation of local failure with larger maximum tumor diameter (p = 0.0008), closer proximity to the fovea (p = 0.0001), lower radiation dose (p = 0.0437), and smaller ultrasound height (p = 0.0034). The actuarial incidence of distant metastases is 12% at 5 years with multivariate analysis showing significant correlation only with maximum tumor diameter (p = 0.0064). Visual outcome is 20/200 or better in 58% of patients. CONCLUSION: While the tumor control rates appear favorable, ocular morbidity is significant. A current randomized trial comparing 125I plaque with Helium ion therapy is in progress with specific comparison of tumor control, survival, and visual outcome.
Assuntos
Braquiterapia , Radioisótopos do Iodo/uso terapêutico , Melanoma/radioterapia , Neoplasias Uveais/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Melanoma/epidemiologia , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia/epidemiologia , Estudos Retrospectivos , Neoplasias Uveais/epidemiologiaRESUMO
PURPOSE: The main objectives of this study were (a) to review the treatment results of primary head and neck soft-tissue sarcoma at our institution, (b) to identify important prognostic factors in local control and survival, and (c) to assess the efficacy of salvage therapy. METHODS AND MATERIALS: Sixty-five patients were treated at the University of California, San Francisco, between 1961 and 1993. Seventeen patients (27%) had low-grade, 10 (15%) had intermediate-grade, and 38 (58%) had high-grade sarcomas. Tumors were > 5 cm in 35 patients. Local management consisted of surgery alone in 14 patients (22%), surgery and radiotherapy in 40 (61%), and radiotherapy alone in 11 (17%) patients. The median follow-up was 64 months. RESULTS: The 5-year actuarial local control rate of the entire group was 66%. Tumor size and grade were important predictors for local control on multivariate analysis. The actuarial local control rate at 5 years was 92% for T1 vs. 40% for T2 primaries (p = 0.004), and 80% for Grade 1-2 vs. 48% for Grade 3 tumors (p = 0.01). None of the patients treated with radiotherapy alone with a dose of 50-65 Gy were controlled locally. Combined radiotherapy and surgery appeared to yield superior local control compared to surgery alone (77% vs. 59%); however, the difference was not statistically significant. The 5-year actuarial overall and cause-specific survivals were 56% and 60%, respectively. Unfavorable prognostic factors for cause-specific survival on multivariate analysis were age > 55 (p = 0.009), high tumor grade (p = 0.0002), inadequate surgery (p = 0.008), and positive surgical margins (p = 0.0009). In patients who underwent salvage therapy for treatment failure, the 5-year actuarial survival after salvage treatment was 26%. CONCLUSION: Tumor size and grade were important predictors for local control. Age, grade, adequacy of surgery, and status of surgical margins were significant prognostic factors for survival. There was a trend of improved local control with combined surgery and radiotherapy compared to either modality alone for high-risk patients. Radiotherapy alone with doses < or = 65 Gy was insufficient for control of gross disease. Aggressive salvage therapy was worthwhile in patients whose disease was uncontrolled after the initial treatment.