RESUMO
Developing technologies for efficient targeted drug delivery for oncotherapy requires new methods to analyze the features of micro- and nanoscale distributions of antitumor drugs in cells and tissues. A new approach to three-dimensional analysis of the intracellular distribution of cytostatics was developed using fluorescence scanning optical-probe nanotomography. A correlative analysis of the nanostructure and distribution of injected doxorubicin in MCF-7 human breast adenocarcinoma cells revealed the features of drug penetration and accumulation in the cell. The technology is based on the principles of scanning optical probe nanotomography and is applicable to studying the distribution patterns of various fluorescent or fluorescence-labelled substances in cells and tissues.
Assuntos
Adenocarcinoma , Neoplasias da Mama , Humanos , Feminino , Células MCF-7 , Corantes Fluorescentes , Doxorrubicina/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Adenocarcinoma/tratamento farmacológicoRESUMO
The development of effective biomedical technologies using magnetic nanoparticles (MNPs) for the tasks of oncotherapy and nanodiagnostics requires the development and implementation of new methods for the analysis of micro- and nanoscale distributions of MNPs in the volume of cells and tissues. The paper presents a new approach to three-dimensional analysis of MNP distributions - scanning magnetic force nanotomography as applied to the study of tumor tissues. Correlative reconstruction of MNP distributions and nanostructure features of the studied tissues made it possible to quantitatively estimate the parameters of three-dimensional distributions of composite nanoparticles based on silicon and iron oxide obtained by femtosecond laser ablation and injected intravenously and intratumorally into tumor tissue samples of B16/F1 mouse melanoma. The developed technology based on the principles of scanning probe nanotomography is applicable for studying the features of three-dimensional micro- and nanoscale distributions of magnetic nanoparticles in biomaterials, cells and tissues of various types.
Assuntos
Nanopartículas de Magnetita , Melanoma Experimental , Nanopartículas , Animais , Materiais Biocompatíveis , Fenômenos Magnéticos , Melanoma Experimental/diagnóstico por imagem , Camundongos , Nanopartículas/químicaRESUMO
Creation of new effective bio-artificial structures for tissue engineering and regenerative medicine requires development and implementation of new technological approaches for analysis of micro- and nanostructural features of constructs based on biomaterials and their interaction with cells. A new method of three-dimensional multiparametric analysis of nanostructure, scanning optical probe nanotomography, is presented in this paper, applied to the analysis of cells and biomaterials. Correlative reconstruction of fluorescent marker distributions and nanostructure features allows quantitative evaluation of a number of parameters of three-dimensional nanomorphology of fibroblasts and human hepatocarcinoma cells Hep-G2, adhered to biodegradable scaffolds based on silk fibroin. The developed technology with use of scanning optical probe nanotomography is applicable to investigation of three-dimensional micro- and nanostructure features of biomaterials and cells of different types.
Assuntos
Materiais BiocompatíveisRESUMO
BACKGROUND: To assess the efficacy and safety of a metronomic schedule of oral vinorelbine (mVNR) in advanced non-small-cell lung cancer (NSCLC) in patients unfit for platinum-based combination chemotherapy. PATIENTS AND METHODS: This was a multicenter, prospective, randomized, open-label phase II study in treatment-naive patients with TNM stage IIIB/IV NSCLC. Patients received mVNR at a fixed dose of 50 mg × 3 or standard schedule 60-80 mg/m2 weekly until disease progression or unacceptable toxicity. The primary endpoint was progression-free survival (PFS) without grade 4 toxicity (G4PFS; NCI-CTC v4). Main secondary objectives were safety, disease control rate (DCR) without grade 4 toxicity (G4DCR), DCR, PFS, overall survival (OS) and quality of life (QoL). RESULTS: A total of 167 patients were included, 83 and 84 patients in the mVNR and standard arms, respectively. The median G4PFS was 4.0 months [95% confidence interval (CI): 2.6-4.3] and 2.2 months (95% CI: 1.5-2.9), hazard ration (HR) = 0.63 (95% CI: 0.45-0.88), P = 0.0068 in favor of metronomic arm; G4DCR was 45.8% and 26.8% in the mVNR and standard arms, respectively. Grade 3-4 treatment-related adverse events were less frequent in the mVNR arm (25.3% versus 54.4%) mainly owing to a reduction in all grades (15.7% versus 51.9%) and grade 3-4 neutropenia (10.8% versus 42%). PFS was 4.3 (95% CI: 3.3-5.1) and 3.9 months (95% CI: 2.8-5.2) in mVNR and standard arms, respectively. No difference in median OS was observed. QoL was comparable between arms. CONCLUSIONS: Metronomic oral vinorelbine significantly prolonged median G4PFS in advanced NSCLC patients unfit for platinum combinations as first-line treatment. It was associated with a clear reduction in toxicity and may be considered as an important option in this challenging population.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Pulmão , Neoplasias Pulmonares/tratamento farmacológico , Platina/uso terapêutico , Estudos Prospectivos , Qualidade de Vida , Vinorelbina/uso terapêuticoRESUMO
Alzheimer's disease (AD) is a frequent pathology, with a poor prognosis, for which no curative treatment is available in 2018. AD prevention is an important issue, and is an important research topic. In this manuscript, we have synthesized the literature reviews and meta-analyses relating to modifiable risk factors associated with AD. Smoking, diabetes, high blood pressure, obesity, hypercholesterolemia, physical inactivity, depression, head trauma, heart failure, bleeding and ischemic strokes, sleep apnea syndrome appeared to be associated with an increased risk of AD. In addition to these well-known associations, we highlight here the existence of associated factors less described: hyperhomocysteinemia, hearing loss, essential tremor, occupational exposure to magnetic fields. On the contrary, some oral antidiabetic drugs, education and intellectual activity, a Mediterranean-type diet or using Healthy Diet Indicator, consumption of unsaturated fatty acids seemed to have a protective effect. Better knowledge of risk factors for AD allows for better identification of patients at risk. This may contribute to the emergence of prevention policies to delay or prevent the onset of AD.
Assuntos
Doença de Alzheimer/epidemiologia , Literatura de Revisão como Assunto , Fatores de Risco , Traumatismos Craniocerebrais/epidemiologia , Depressão/epidemiologia , Diabetes Mellitus/epidemiologia , Dieta Mediterrânea/estatística & dados numéricos , Gorduras Insaturadas na Dieta , Escolaridade , Tremor Essencial/epidemiologia , Perda Auditiva/epidemiologia , Insuficiência Cardíaca/epidemiologia , Humanos , Hiper-Homocisteinemia/epidemiologia , Hipertensão/epidemiologia , Hipoglicemiantes/uso terapêutico , Campos Magnéticos , Metanálise como Assunto , Obesidade/epidemiologia , Exposição Ocupacional/estatística & dados numéricos , Fatores de Proteção , Comportamento Sedentário , Síndromes da Apneia do Sono/epidemiologia , Fumar/epidemiologia , Acidente Vascular Cerebral/epidemiologiaAssuntos
Hidropisia Fetal/terapia , Síndrome do Coração Esquerdo Hipoplásico/embriologia , Complicações na Gravidez/terapia , Resultado da Gravidez , Transtornos Relacionados ao Uso de Substâncias/complicações , Adulto , Alcoolismo/complicações , Coartação Aórtica/etiologia , Coartação Aórtica/cirurgia , Cannabis/efeitos adversos , Transtornos Relacionados ao Uso de Cocaína/complicações , Epilepsia/complicações , Epilepsia/tratamento farmacológico , Feminino , Transtornos do Espectro Alcoólico Fetal/diagnóstico , Idade Gestacional , Humanos , Síndrome do Coração Esquerdo Hipoplásico/complicações , Síndrome do Coração Esquerdo Hipoplásico/diagnóstico por imagem , Recém-Nascido , Masculino , Oxazolidinonas/efeitos adversos , Oxazolidinonas/uso terapêutico , Gravidez , Cuidado Pré-Natal , Prognóstico , Uso de Tabaco/efeitos adversos , Ultrassonografia Pré-NatalRESUMO
OBJECTIVE: Assess the impact of routine injection of 5 units of oxytocin as soon as the anterior shoulder is delivered on the incidence of postpartum haemorrhage (PPH) in a context of daily practice. MATERIALS AND METHODS: Single-centre before-and-after study evaluating the effect of a change in the protocol for PPH prevention as applied in our obstetrical unit. During the first period, oxytocin (5 units) was to be injected only in case of PPH risk factors. During the second period, the injection was systematic. RESULTS: In the "before" study period, there were 1953 patients vaginal deliveries and 843 (43%) oxytocin injections, with a protocol compliance of 85%. In the "after" study period, 2018 women had vaginal deliveries and 1911 (95%) had an oxytocin injection (protocol compliance: 95%). The whole study period was associated with a reduced risk of moderate haemorrhage (13.4% vs. 9.2%, P<0.001), but no significant reduced risk of severe haemorrhage was observed (2.1% vs. 2.0%, P=0.79). After logistic regression, the study period remained associated with a significant reduction in the risk of moderate PPH (OR=0.72 [0.58-0.89]). CONCLUSION: Routine injection of 5 units of oxytocin makes it possible to reduce the risk of moderate PPH, but it does not affect the risk of severe PPH.
Assuntos
Parto Obstétrico/efeitos adversos , Ocitocina/administração & dosagem , Hemorragia Pós-Parto/etiologia , Hemorragia Pós-Parto/prevenção & controle , Adulto , Quimioprevenção/métodos , Quimioprevenção/normas , Parto Obstétrico/normas , Parto Obstétrico/estatística & dados numéricos , Feminino , Humanos , Incidência , Injeções , Terceira Fase do Trabalho de Parto , Hemorragia Pós-Parto/epidemiologia , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/estatística & dados numéricos , Gravidez , Adulto JovemRESUMO
OBJECTIVE: The aim of this prospective study was to determine the influence of anti-inflammatory drugs on the severity of odontogenic cellulitis in patients admitted to our hospital emergency unit. STUDY DESIGN: The study was made from April 30 to October 31 2006. The clinical and pharmacological data was prospectively collected at admission, during hospitalization, and during systematic follow-up. We first studied the whole population and then compared the 2 groups: patients having received anti-inflammatory drugs before admission or not. RESULTS: Two hundred and sixty-seven patients were included. The only severity criterion significantly different between the 2 groups was spreading of cervical lymphangitis (P=0.028). None of the 4 studied parameters was identified as a risk factor for spreading of cervical lymphangitis in multivariate analysis: anti-inflammatory use (OR=5.99, 95%CI [0.71-50.88]), alcohol abuse (OR=4.00, 95%CI [0.66-24.12]), dental hygiene (OR=1.53, 95%CI [0.36-6.56]), and tobacco use (OR=0.27, 95%CI [0.57-1.28]). DISCUSSION: The use of anti-inflammatory drugs during the initial phase of an odontogenic infection was not related to the severity of infection.
Assuntos
Anti-Inflamatórios/efeitos adversos , Celulite (Flegmão)/etiologia , Celulite (Flegmão)/patologia , Doenças Estomatognáticas/complicações , Adolescente , Adulto , Antibacterianos/uso terapêutico , Celulite (Flegmão)/tratamento farmacológico , Celulite (Flegmão)/epidemiologia , Progressão da Doença , Face , Feminino , Infecção Focal Dentária/tratamento farmacológico , Infecção Focal Dentária/epidemiologia , Infecção Focal Dentária/patologia , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Pescoço , Doenças Estomatognáticas/tratamento farmacológico , Doenças Estomatognáticas/epidemiologia , Doenças Estomatognáticas/patologia , Adulto JovemRESUMO
OBJECTIVE: The aim of this prospective study was to determine the influence of anti-inflammatory drugs on the severity of odontogenic cellulitis in patients admitted to our hospital emergency unit. STUDY DESIGN: The study was made from April 30 to October 31 2006. The clinical and pharmacological data was prospectively collected at admission, during hospitalization, and during systematic follow-up. We first studied the whole population and then compared the two groups: patients having received anti-inflammatory drugs before admission or not. RESULTS: Two hundred and sixty-seven patients were included. The only severity criterion significantly different between the two groups was spreading of cervical lymphangitis (P = 0.028). None of the four studied parameters was identified as a risk factor for spreading of cervical lymphangitis in multivariate analysis: anti-inflammatory use (OR = 5.99, 95%CI [0.71-50.88]), alcohol abuse (OR = 4.00, 95%CI [0.66-24.12]), dental hygiene (OR = 1.53, 95%CI [0.36-6.56]), and tobacco use (OR = 0.27, 95%CI [0.57-1.28]). DISCUSSION: The use of anti-inflammatory drugs during the initial phase of an odontogenic infection was not related to the severity of infection.
Assuntos
Anti-Inflamatórios/uso terapêutico , Celulite (Flegmão)/etiologia , Doenças Estomatognáticas/complicações , Adolescente , Adulto , Celulite (Flegmão)/epidemiologia , Celulite (Flegmão)/terapia , Face , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Pescoço , Admissão do Paciente/estatística & dados numéricos , Doenças Estomatognáticas/epidemiologia , Doenças Estomatognáticas/terapia , Adulto JovemRESUMO
Desmopressin is a synthetic vasopressin analog that increases the plasma levels of coagulation factor VIII, von Willebrand factor, and tissue plasminogen activator. This hemostatic agent, which can be administered either parenterally or intranasally, has been approved for use in the prevention and treatment of hemorrhagic events during surgery in patients with hemophilia A, in cases of prolonged idiopathic bleeding, and for complications associated with platelet antiaggregant therapy. This case report describes cardiac toxicity associated with desmopressin administered according to the recommended indications: a 55-year-old woman diagnosed with Wegener's granulomatosis (WG) was treated with desmopressin to improve hemostasis and shorten bleeding time before a planned renal biopsy. She developed cardiac arrest within 60 minutes of the desmopressin injection. Cardiopulmonary resuscitation began immediately and was successful, although the patient subsequently died of WG-associated complications. Desmopressin administration thus appears, in some cases, to be associated with a high risk of thrombotic events, possibly by stimulating the rapid release of endothelial factors such as an abnormal multimeric form of von Willebrand factor, which might cause platelet aggregation. Clinicians should be aware of the possible occurrence of this little-known but potentially serious cardiac event associated with desmopressin administration and be prepared to initiate cardiopulmonary resuscitation immediately if needed.
Assuntos
Desamino Arginina Vasopressina/efeitos adversos , Granulomatose com Poliangiite/complicações , Parada Cardíaca/induzido quimicamente , Hemostáticos/efeitos adversos , Infarto do Miocárdio/etiologia , Biopolímeros , Biópsia , Tempo de Sangramento , Desamino Arginina Vasopressina/uso terapêutico , Progressão da Doença , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Evolução Fatal , Feminino , Granulomatose com Poliangiite/sangue , Granulomatose com Poliangiite/tratamento farmacológico , Hemorragia/prevenção & controle , Hemostáticos/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Rim/patologia , Pessoa de Meia-Idade , Infarto do Miocárdio/tratamento farmacológico , Tromboembolia/etiologia , Terapia Trombolítica , Fator de von Willebrand/química , Fator de von Willebrand/metabolismoRESUMO
We report the case of a young woman who suffered from a seizure after use of almotriptan. There was a recurrence with ergotamine. We discuss possible link with susceptibility genes.
Assuntos
Transtornos de Enxaqueca/complicações , Convulsões/induzido quimicamente , Triptaminas/efeitos adversos , Canais de Cálcio/genética , Eletroencefalografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Transtornos de Enxaqueca/tratamento farmacológico , Transtornos de Enxaqueca/genética , Mutação , Paresia/etiologia , Tomografia por Emissão de Pósitrons , ATPase Trocadora de Sódio-Potássio/genética , Triptaminas/uso terapêuticoRESUMO
BACKGROUND: Leflunomide is prescribed in inflammatory rheumatisms. Cutaneous side effects have rarely been described. We report the case of a patient presenting skin necrosis attributed to this drug. PATIENTS AND METHODS: A 73-year-old woman had been taking leflunomide for psoriatic arthritis for one year and subsequently, developed three abdominal ulcerations and necrosis of one hallux. No immunological, vascular or neoplastic aetiology was found. Corticotherapy was started, based on a hypothesis of vasculitis, but lesions progressed, leading to amputation of the hallux. Leflunomide was stopped and the ulcerations healed completely within 12 weeks, whereas prolonged local treatment had failed to yield any improvement. DISCUSSION: Skin necrosis due to leflunomide is rare; we found seven cases in the literature. Ulcerations may occur anywhere. Potentially life-threatening glomerulonephritis with mesangial deposits may be associated. Discontinuation of leflunomide followed by wash-out with cholestyramine allows healing. Corticosteroids or cyclophosphamide are sometimes necessary. The ulcerations appear to be result from excessive immunomodulation in the skin or from an inhibiting role of leflunomide on the epidermal growth factor receptor. CONCLUSION: In the absence of any demonstrated aetiology in patients presenting ulcerations or skin necrosis, a contributory role of leflunomide must be considered, even in cases of prolonged use.
Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Artrite Psoriásica/tratamento farmacológico , Isoxazóis/efeitos adversos , Pele/patologia , Abdome/patologia , Idoso , Feminino , Seguimentos , Humanos , Leflunomida , Necrose , Pele/efeitos dos fármacos , Fatores de TempoRESUMO
BACKGROUND AND OBJECTIVE: Cases of erythroblastopenia, as an adverse effect to epoetin (EPREX), led to its use being restricted in Europe to the intravenous route (i.v.) since July 2002, in patients with chronic renal insufficiency. This work aimed at investigating the biological, pharmaceutical and economic impacts of this change in policy. METHODS: We retrospectively compared the characteristics of 99 haemodialysis patients treated with epoetin at the time of the recommendation (July 2002) and 5 months after the policy change (November 2002). RESULTS: In July 2002, 69 patients who were receiving EPREX subcutaneously (s.c./i.v. group) changed to the i.v. route of administration. Thirty other patients were already on i.v. epoetin (i.v. group). During the study period, the dose of epoetin increased significantly in the s.c./i.v. group but not in the i.v. group (46.83 +/- 10.20 UI/kg/week vs. 2.17 +/- 20.14 UI/kg/week respectively). This increased dosage was accounted for by a subgroup of 42 patients in the s.c./i.v. group while the others had dosage variations similar to those observed in the i.v. group. There were no significant clinical and biological changes associated with this change in route of administration. However, the change in policy led to the haemodialysis ward incurring an additional cost of 265,905 Euro (+32.7%) or an average annual extra cost of 1841 +/- 401 Euro per patient. CONCLUSION: Changing the route of administration of EPREX from the i.v. to the subcutaneous route required an increase in dosage and in substantial additional cost.
Assuntos
Eritropoetina/administração & dosagem , Hematínicos/administração & dosagem , Diálise Renal/economia , Idoso , Análise Custo-Benefício , Epoetina alfa , Feminino , França , Humanos , Injeções Intravenosas , Injeções Subcutâneas , Masculino , Vigilância de Produtos Comercializados , Proteínas Recombinantes , Estudos RetrospectivosRESUMO
A novel drainage implant for glaucoma filtering surgery (MESH) is proposed. After various expanded poly(tetrafluoroethylene) (e-PFTE) materials were evaluated, the feasibility and the short-term safety of the technique were assessed in this first pilot study in the rabbit. The porous structure and the in vitro resistance to aqueous flow of seven different e-PTFE membranes (5-80 microm average pore size) were compared. Eight Dutch pigmented rabbits were implanted with the T-shaped MESH implants made from either 20- or 50-microm average pore size e-PTFE membranes. Clinical examination, intraocular pressure (IOP) measurements, and histology analyses were performed over a period of 3 months. The contralateral nonoperated eyes served as controls. MESH implantation took less than 7 min. No postoperative hypotony, migration, or extrusion of the implant and no intraocular inflammation or infection occurred. A significant IOP reduction in the implanted eyes was obtained past postoperative day 21 with the 20-microm material implant. The drainage efficacy was correlated with the degree of colonization of the porous materials and the inner spacing of the implant as observed by histology. With a filtering patency 3 times longer than conventional trabeculectomy and laser sclerectomy, MESH surgery is a promising technique for glaucoma treatment. Further studies are underway to enhance the device efficacy and understand the mechanism of filtration.
Assuntos
Materiais Biocompatíveis , Implantes para Drenagem de Glaucoma , Glaucoma/cirurgia , Politetrafluoretileno , Animais , Materiais Biocompatíveis/efeitos adversos , Materiais Biocompatíveis/química , Humanos , Politetrafluoretileno/efeitos adversos , Politetrafluoretileno/química , CoelhosRESUMO
Poly(L-lysine citramide) was synthesized to serve as a polymeric bioresorbable drug carrier. It was previously shown that low molecular weight poly(L-lysine citramide) hydrophobized with heptyl and lauryl side chains (PLCA-C7(p) with p=43 and 60%; and PLCA-C12(p), with p=68, 75 and 100%) formed aggregates in aqueous media. The size of these aggregates was found to depend on the balance between repulsive electrostatic charges and attractive hydrophobic interactions, on the degree of ionization, and on the ionic strength. In this paper, the formation of these aggregates was further investigated by fluorescence probing, using two polarity sensitive molecules, pyrene and Nile Red, which were physically entrapped within the lipophilic core of the aggregates. In contrast to other micellar structures formed by surfactants and amphiphilic block copolymers, aggregates were observed even at very low polymer concentrations. The capacity of the hydrophobic domains to accommodate lipophilic molecules via physical entrapment was demonstrated with progesterone.
Assuntos
Portadores de Fármacos/química , Nylons/química , Oxazinas/química , Progesterona/química , Pirenos/química , Absorção , Química Farmacêutica , Fluorescência , Corantes Fluorescentes/química , Modelos Biológicos , Nylons/síntese química , Concentração Osmolar , Polilisina/análogos & derivados , Solubilidade , Água/químicaRESUMO
Future surgical strategies to restore neurological function in the damaged human spinal cord may involve replacement of nerve tissue with cultured Schwann cells using biodegradable guiding implants. We have studied the in vitro and in vivo degradability of various aliphatic polyesters as well as their effects on rat Schwann cells in vitro and on spinal cord tissue in vivo. In vitro, cylinders made of poly(D,L-lactic-co-glycolic acid) 50:50 (PLA25GA50) started to degrade at 7 days, compared with 28 days for cylinders made of poly(D,L-lactic acid) (PLA50). This faster degradation of PLA25GA50 was reflected by a much higher absorption of water. In vivo, after implantation of PLA25GA50 or PLA50 cylinders between the stumps of a completely transected adult rat spinal cord, the decrease in molecular weight of both polymers was similar to that found in vitro. In vitro degradation of poly(L-lactic acid) (PLA100) mixed with increasing amounts of PLA100 oligomers also was determined. The degradation rate of PLA100 mixed with 30% oligomers was found to be similar to that of PLA50. In vitro, PLA25GA50 and the breakdown products had no adverse effect on the morphology, survival, and proliferation of cultured rat Schwann cells. In vivo, PLA25GA50 cylinders were integrated into the spinal tissue 2 weeks after implantation, unlike PLA50 cylinders. At all time points after surgery, the glial and inflammatory response near the lesion site was largely similar in both experimental and control animals. At time points later than 1 week, neurofilament-positive fibers were found within PLA25GA50 cylinders or the remains thereof. Growth-associated protein 43, which is indicative of regenerating axons, was observed in fibers in the vicinity of the injury site and in the remains of PLA25GA50 cylinders. The results suggest that poly(alpha-hydroxyacids) are likely candidates for application in spinal cord regeneration paradigms involving Schwann cells.
Assuntos
Materiais Biocompatíveis , Ácido Láctico , Ácido Poliglicólico , Polímeros , Células de Schwann/citologia , Medula Espinal/cirurgia , Animais , Biotransformação , Células Cultivadas , Feminino , Humanos , Inflamação/etiologia , Inflamação/patologia , Ácido Láctico/farmacocinética , Macrófagos/patologia , Monócitos/patologia , Ácido Poliglicólico/farmacocinética , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros/farmacocinética , Ratos , Ratos Endogâmicos F344 , Células de Schwann/efeitos dos fármacos , Células de Schwann/metabolismo , Medula Espinal/citologia , Medula Espinal/fisiologia , Traumatismos da Medula Espinal/cirurgia , Fatores de TempoRESUMO
BACKGROUND AND OBJECTIVE: To evaluate the efficacy of a novel filtering implant, a synthetic meshwork (MESH), with or without heparin or sodium hyaluronate amendment. MATERIALS AND METHODS: Eighteen eyes of 18 rabbits received MESH surgery. The eyes were divided into three subgroups. Six eyes received the MESH implant with no modification (group 1), 6 eyes received MESH saturated with heparin (group 2), and 6 eyes received MESH with sodium hyaluronate administration into the anterior chamber during surgery (group 3). Intraocular pressure (IOP) and outflow facility were measured during a period of 6 months. RESULTS: The MESH-implanted eyes showed lower IOP and higher outflow facility than control eyes up to postoperative days 119 and 49, respectively (P > .05). Earliest functional failure was seen in group 3 and latest in group 2. CONCLUSION: MESH implant surgery showed a long-term efficacy in reducing IOP. The beneficial effects of added heparin were limited. Sodium hyaluronate administration reduced the efficacy of the implant device.
Assuntos
Cirurgia Filtrante/métodos , Glaucoma/cirurgia , Heparina de Baixo Peso Molecular/administração & dosagem , Ácido Hialurônico/administração & dosagem , Politetrafluoretileno , Próteses e Implantes , Animais , Segmento Anterior do Olho/efeitos dos fármacos , Segmento Anterior do Olho/metabolismo , Segmento Anterior do Olho/patologia , Humor Aquoso/metabolismo , Materiais Biocompatíveis , Quimioterapia Adjuvante , Drenagem/métodos , Glaucoma/patologia , Pressão Intraocular , Complicações Pós-Operatórias , Implantação de Prótese , CoelhosRESUMO
OBJECTIVE: The aim of the work was to develop a standard protocol of colour velocity and spectral Doppler ultrasound (D.-US) of liver tumour vascularization and to estimate the value of this method in differentiation of liver tumours. METHODS: In 1994 and 1995, 68 patients with 128 primary and secondary liver tumours were observed. The final diagnosis was histologically verified. The diagnostic system Acuson 128 X/P 10M (Mountain View, CA) with 3.5 MHz convex abdominal probe was used. Qualitative features (vessel presence, vessel location and waveform of tumour vessel blood flow) and quantitative features (vessel quantity per cm2, vessel diameter, maximum velocity (Vmax), and resistance index (RI) of tumour artery, and Vmax of tumour portal vein) were included in the D.-US protocol. The differences in these features among various liver tumours were retrospectively analysed. RESULTS: The tumour vascularization was found more frequently in hepatocellular carcinoma (HCC) than in cavernous hemagioma (CavHA) or metastatic liver lesion (MLL) (P<0. 01). Among the tumours with detected vascularization, significant differences (P<0.01) were found (1) in vessel presence: (a) around tumour between MLL and HCC with or without liver cirrhosis (LC) or CavHA; (b) in periphery of tumour between HCC,CavHA, benign tumour (BT; hepatocellular adenoma, focal nodular hyperplasia) and MLL; (2) in detection rate of arterial blood flow between HCC with or without LC and CavHA or MLL. The other differences were not statistically significant. CONCLUSIONS: According to our findings D.-US can be used for the differentiation of some liver tumours when using the criteria: (a) vessel presence around or in periphery of tumour, and (b) arterial flow pattern in tumour vessels.
Assuntos
Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Ultrassonografia Doppler , Adolescente , Adulto , Idoso , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Protocolos Clínicos , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
A fiber optic sensor based on enzyme-catalyzed light-emitting reactions has been developed and integrated in a flow-injection analysis (FIA) system. The firefly luciferase, specific for ATP, and the bacterial oxidoreductase/luciferase system, specific for NADH, have been immobilized on preactivated polyamide membranes. ATP and NADH analysis could be performed in the range from 0.1 pmol to 3 nmol and from 0.5 pmol to 1 nmol, respectively. By co-immobilizing these two bioluminescence systems on the same membrane, a multi-function biosensor has been designed allowing the alternate determination of ATP or NADH with the same sensitivity as that obtained with the two different mono-functional biosensors. A partly self-contained biosensor has been also developed for the flow injection analysis of NADH. For this purpose, FMN (one of the substrates of the bacterial bienzymatic system) has been embedded in a synthetic matrix. Different supports have been tested for the non-covalent immobilization of this substrate and its release in the immediate vicinity of the bound enzymes. Using a photo-crosslinked poly(vinyl alcohol) support, 40 reliable assays (CV = 4.5%) could be performed without changing or reloading the matrix.
Assuntos
Trifosfato de Adenosina/análise , Técnicas Biossensoriais , NAD/análise , Animais , Biotecnologia/instrumentação , Biotecnologia/métodos , Besouros , Enzimas Imobilizadas , Tecnologia de Fibra Óptica , Indicadores e Reagentes , Luciferases , Medições Luminescentes , Fibras Ópticas , Oxirredução , OxirredutasesRESUMO
The potential of immobilized enzyme membranes in biosensors has been explored in our group for several years. Although part of our work has been mainly devoted to electrochemical transducers and oxidases for the design of enzyme electrodes, the demand for ultrasensitive and highly selective sensors led us to consider the use of luminescent enzyme systems associated to optical transduction. When considering the need for operational and reliable biosensors in biotechnology, immobilization and stability of the sensing element still remain, in most cases, an unavoidable problem. We recently proposed a very fast and reliable procedure for preparing enzymatic membranes from Pall (Biodyne Immunoaffinity membranes) supplied in a pre-activated form. Both the firefly and bacterial systems as well as peroxidase for the chemiluminescent determination of various analytes, could be bound to such a support. Based on this approach, a fibre-optic sensor with immobilized enzymes has been designed which permits bio- or chemiluminescent analysis of ATP, NADH or H2O2 respectively. With the NADH-based system, other analytes could be detected using coupled dehydrogenases. This device appears very promising and includes the convenience of both the luminescence sensitivity as well as the handling of the biosensor design.