RESUMO
A simple route towards patchy particles with anisotropic patches with respect to a different functionality and directionality is presented. This method is based on microcontact printing of positively charged polyethylenimine (PEI) on silica particles using wrinkled stamps. Due to the wrinkled surface, the number of patches on the particles as well as the distance between two patches can be controlled.
RESUMO
Prostate cancer is still the most common urological cancer of the elderly man. In some patients, a metastatic prostate cancer arises which may remain a stable disease for years with palliative antiandrogen therapy. On average, after 3-4 years, affected men develop a PSA rise and disease progression with the formation of a so-called castration-resistant disease. 5 years ago cytotoxic chemotherapy with docetaxel was the only life-prolonging treatment option in this situation. In the last 5 years, the results of randomised phase III studies have led to the approval of 5 new agents for the treatment of metastatic castration resistant prostate cancer (mCRPC). The results and approval status of the substances, Abiraterone, Enzalutamide, Cabazitaxel, Sipuleucel-T and radium-223 are described below. In addition, some aspects of sequential therapy and possible future molecular approaches are discussed.
Assuntos
Antineoplásicos/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/terapia , Rádio (Elemento)/uso terapêutico , Idoso , Biomarcadores Tumorais/sangue , Humanos , Masculino , Antígeno Prostático Específico/sangue , Neoplasias de Próstata Resistentes à Castração/sangue , Neoplasias de Próstata Resistentes à Castração/patologia , Radioisótopos/uso terapêuticoRESUMO
BACKGROUND: Dexmedetomidine (DEX) is a highly selective alpha(2)-adrenoceptor agonist that has been used increasingly in children. However, the effect of caudal DEX has not been evaluated before in children. This prospective randomized double-blinded study was designed to evaluate the analgesic efficacy of caudal DEX with bupivacaine in providing pain relief over a 24-h period. METHODS: Sixty children (ASA status I) aged 1-6 years undergoing unilateral inguinal hernia repair/orchidopexy were allocated randomly to two groups (n = 30 each). Group B received a caudal injection of bupivacaine 2.5 mg/ml, 1 ml/kg; Group BD received the same dose of bupivacaine mixed with DEX 1 microg/kg during sevoflurane anesthesia. Processed electroencephalogram (bispectral index score), heart rate, blood pressure, pulse oximetry and end-tidal sevoflurane were recorded every 5 min. The characteristics of emergence, objective pain score, sedation score and quality of sleep were recorded post-operatively. Duration of analgesia and requirement for additional analgesics were noted. RESULTS: The end-tidal sevoflurane concentration and the incidence of agitation were significantly lower in the BD group (P < 0.05). The duration of analgesia was significantly longer (P < 0.001) and the total consumption of rescue analgesic was significantly lower in Group BD compared with Group B (P < 0.01). There was no statistically significant difference in hemodynamics between both groups. However, group BD had better quality of sleep and a prolonged duration of sedation (P < 0.05). CONCLUSION: Caudal DEX seems to be a promising adjunct to provide excellent analgesia without side effects over a 24-h period. It has the advantage of keeping the patients calm for a prolonged time. Implications statement: Caudally administered DEX (1 microg/kg), combined with bupivacaine, was associated with an extended duration of post-operative pain relief.
Assuntos
Adjuvantes Anestésicos/farmacologia , Agonistas alfa-Adrenérgicos/uso terapêutico , Analgésicos não Narcóticos/uso terapêutico , Anestesia Caudal/métodos , Anestésicos Locais/farmacologia , Bupivacaína/farmacologia , Dexmedetomidina/farmacologia , Hérnia Inguinal/cirurgia , Hipnóticos e Sedativos/farmacologia , Dor Pós-Operatória/tratamento farmacológico , Adjuvantes Anestésicos/administração & dosagem , Agonistas alfa-Adrenérgicos/farmacocinética , Anestésicos Locais/administração & dosagem , Bupivacaína/administração & dosagem , Criança , Pré-Escolar , Dexmedetomidina/administração & dosagem , Método Duplo-Cego , Sinergismo Farmacológico , Humanos , Hipnóticos e Sedativos/administração & dosagem , Lactente , Masculino , Estudos Prospectivos , Agitação Psicomotora/prevenção & controle , Receptores Adrenérgicos alfa 2/efeitos dos fármacos , Sono/efeitos dos fármacosRESUMO
We investigate the concentration and size dependent self-assembly of cadmium selenide nanoparticles at an oil/water interface. Using a pendant drop tensiometer, we monitor the assembly kinetics and evaluate the effective diffusion coefficients following changes in the interfacial tension for the early and late stages of nanoparticle adsorption. Comparison with the coefficients for free diffusion reveals the energy barrier for particle segregation to the interface. The formation of a nanoparticle monolayer at the oil/water interface is characterised by transmission electron microscopy.
Assuntos
Compostos de Cádmio/química , Nanopartículas/química , Compostos de Selênio/química , Tolueno/química , Adsorção , Compostos de Cádmio/síntese química , Difusão , Cinética , Microscopia Eletrônica de Transmissão/métodos , Tamanho da Partícula , Transição de Fase , Compostos de Selênio/síntese química , Tensão Superficial , Água/químicaRESUMO
We have followed the reorientation kinetics of various block copolymer solutions exposed to an external electric DC field. The characteristic time constants follow a power law indicating that the reorientation is driven by a decrease in electrostatic energy. Moreover, the observed exponent suggests an activated process in line with the expectations for a nucleation and growth process. When properly scaled, the data collapse onto a single master curve spanning several orders of magnitude both in reduced time and in reduced energy. The power law dependence of the rate of reorientation derived from computer simulations based on dynamic density functional theory agrees well with the experimental observations. First experiments in AC electric fields at sufficiently high frequencies confirm the notion that the reorientation process is dominated by differences in the dielectric constants rather than by mobile ions.
RESUMO
We investigate the microscopic mechanisms responsible for microdomain alignment in block copolymer solutions exposed to an electric field. Using time-resolved synchrotron small-angle x-ray scattering, we reveal two distinct processes, i.e., grain boundary migration and rotation of entire grains, as the two dominant microscopic mechanisms. The former dominates in weakly segregating systems, while the latter is predominant in strongly segregated systems. The kinetics of the processes are followed as a function of polymer concentration and temperature and are correlated to the solution viscosity.
RESUMO
The basidiomycete Nidula niveo-tomentosa produced 4-(4-hydroxyphenyl)-butan-2-one (raspberry ketone), one of the character impact components of raspberry flavor, and its corresponding alcohol. A systematic attempt was made to improve the productivity of this fungus. Variation of nutrient medium composition, precursor amount, time of supplementation, and cultivation period yielded a 50-fold increase in metabolite concentrations. Raspberry ketone and alcohol were easily isolated from the culture medium by solvent extraction. Glycosidically bound forms or accumulation of raspberry compounds in fungal cells were not detected. This microbial process offers an alternative for the production of natural raspberry flavor.
Assuntos
Basidiomycota/citologia , Basidiomycota/metabolismo , Butanonas/metabolismo , Microbiologia Industrial/métodos , Células Cultivadas , Meios de Cultura , Nitrogênio/metabolismo , Fenilalanina/metabolismo , Fatores de Tempo , Tirosina/metabolismoRESUMO
New hope for the treatment of type 1 diabetes has recently emerged from the encouraging results of islet cell transplantation in humans during the last few years. Although still facing considerable problems, the challenge to achieving insulin independence has been overcome in some patients who received an islet graft. However, the success of clinical trials is still limited by the inability to transplant enough viable human islets to compensate for the insulin-deficient state, the number of islets that engraft following transplantation, the rejection process, and the recurrence of autoimmunity. The important advances in immunosuppressive regimens, organ procurement techniques, isolation techniques, and availability of defined collagenase blends have contributed to the continuing promise of making islet cell transplantation the treatment of choice for type 1 diabetes mellitus.
Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Transplante das Ilhotas Pancreáticas , Diabetes Mellitus Tipo 1/fisiopatologia , Rejeição de Enxerto , Humanos , Transplante das Ilhotas Pancreáticas/imunologia , Transplante das Ilhotas Pancreáticas/fisiologia , Obtenção de Tecidos e Órgãos , Tolerância ao TransplanteRESUMO
PURPOSE: To describe the care of a pregnant woman with von Hippel-Lindau disease (VHLD) and intracranial mass lesions. CLINICAL FEATURES: A 30-yr-old primigravida with VHLD at 35 weeks gestation was seen at the obstetric anesthesia clinic because she wished an epidural analgesia during labour. She had a history of headaches and dizziness. Further investigations showed an enlarged cerebellar hemangioblastoma with significant local mass effects. A combined Cesarean section delivery and posterior fossa craniotomy was performed at 37 weeks gestation. A general anesthetic with fentanyl, rocuronium, nitrous oxide, oxygen and isoflurane was given for Cesarean section delivery. After delivery, isoflurane was reduced and propofol infusion at 4-8 mg x kg(-1) x hr(-1) was initiated. The patient had an uneventful operative course and recovery. CONCLUSIONS: Patients with VHLD may have worsening of preexisting lesions or develop other lesions during pregnancy. Some asymptomatic lesions can increase the risk for anesthesia complications. These patients need comprehensive assessment before administration of anesthesia.