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1.
Ann Oncol ; 34(11): 1015-1024, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37657554

RESUMO

BACKGROUND: The optimal time to surgery (TTS) after neoadjuvant chemoradiotherapy (nCRT) for oesophageal cancer is unknown and has traditionally been 4-6 weeks in clinical practice. Observational studies have suggested better outcomes, especially in terms of histological response, after prolonged delay of up to 3 months after nCRT. The NeoRes II trial is the first randomised trial to compare standard to prolonged TTS after nCRT for oesophageal cancer. PATIENTS AND METHODS: Patients with resectable, locally advanced oesophageal cancer were randomly assigned to standard delay of surgery of 4-6 weeks or prolonged delay of 10-12 weeks after nCRT. The primary endpoint was complete histological response of the primary tumour in patients with adenocarcinoma (AC). Secondary endpoints included histological tumour response, resection margins, overall and progression-free survival in all patients and stratified by histologic type. RESULTS: Between February 2015 and March 2019, 249 patients from 10 participating centres in Sweden, Norway and Germany were randomised: 125 to standard and 124 to prolonged TTS. There was no significant difference in complete histological response between AC patients allocated to standard (21%) compared to prolonged (26%) TTS (P = 0.429). Tumour regression, resection margins and number of resected lymph nodes, total and metastatic, did not differ between the allocated interventions. The first quartile overall survival in patients allocated to standard TTS was 26.5 months compared to 14.2 months after prolonged TTS (P = 0.003) and the overall risk of death during follow-up was 35% higher after prolonged delay (hazard ratio 1.35, 95% confidence interval 0.94-1.95, P = 0.107). CONCLUSION: Prolonged TTS did not improve histological complete response or other pathological endpoints, while there was a strong trend towards worse survival, suggesting caution in routinely delaying surgery for >6 weeks after nCRT.


Assuntos
Adenocarcinoma , Neoplasias Esofágicas , Humanos , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/cirurgia , Quimiorradioterapia , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/cirurgia , Margens de Excisão , Terapia Neoadjuvante , Intervalo Livre de Progressão , Tempo para o Tratamento
2.
Stem Cells Int ; 2019: 3010656, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31871466

RESUMO

Current limitations in the efficacy of treatments for chronic respiratory disorders position them as prospective regenerative medicine therapeutic targets. A substantial barrier to these ambitions is that research requires large numbers of cells whose acquisition is hindered by the limited availability of human tissue samples leading to an overreliance on physiologically dissimilar rodents. The development of cell culture strategies for airway cells from large mammals will more effectively support the transition from basic research to clinical therapy. Using readily available porcine lungs, we isolated conducting airway tissue and subsequently a large number of porcine airway epithelial cells (pAECs) using a digestion and mechanical scraping technique. Cells were cultured in a variety of culture media formulations, both foetal bovine serum-containing and serum-free media, in air (21%) and physiological (2%) oxygen tension and in the presence and absence of Rho kinase inhibitor Y-27362 (RI). Cell number at isolation and subsequent population doublings were determined; cells were characterised during culture and following differentiation by immunofluorescence, histology, and IL-8 ELISA. Cells were positive for epithelial markers (pan-cytokeratin and E-cadherin) and negative for fibroblastic markers (vimentin and smooth muscle actin). Supplementation of cultures with Y-27632 allowed for unlimited expansion whilst sustaining an epithelial phenotype. Early passage pAECs readily produced differentiated air-liquid interface (ALI) cultures with a capacity for mucociliary differentiation retained after substantial expansion, strongly modulated by the culture condition applied. Primary pAECs will be a useful tool to further respiratory-oriented research whilst RI-expanded pAECs are a promising tool, particularly with further optimisation of culture conditions.

3.
Physiol Behav ; 194: 333-340, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29933029

RESUMO

PURPOSE: This study examined the effect of environmental temperature deception on the rating of perceived exertion (RPE) during 30 min of fixed-intensity cycling in the heat. METHODS: Eleven trained male cyclists completed an incremental cycling test and four experimental trials. Trials consisted of 30 min cycling at 50% Pmax, once in 24 °C (CON) and three times in 33 °C. In the hot trials, participants were provided with accurate temperature feedback (HOT), or were deceived to believe the temperature was 28 °C (DECLOW) or 38 °C (DECHIGH). During cycling, RPE was recorded every 5 min. Rectal and skin temperature, heart rate and oxygen uptake were continuously measured. Data were analysed using linear mixed model methods in a Bayesian framework, magnitude-based inferences (Cohens d), and the probability that d exceeded the smallest worthwhile change. RESULTS: RPE was higher in the heat compared to CON, but not statistically different between the hot conditions (mean [95% credible interval]; DECLOW: 13.0 [11.9, 14.1]; HOT: 13.0 [11.9, 14.1]; DECHIGH: 13.1 [12.0, 14.2]). Heart rate was significantly higher in DECHIGH (141 b·min-1 [132, 149]) compared to all other conditions (DECLOW: 138 b·min-1 [129, 146]; HOT: 138 b·min-1 [129, 145]) after 10 min; however, this did not alter RPE. All other physiological variables did not differ between the hot conditions. CONCLUSION: Participants were under the impression they were cycling in different environments; however, this did not influence RPE. These data suggest that for trained cyclists, an awareness of environmental temperature does not contribute to the generation of RPE when exercising at a fixed intensity in the heat.


Assuntos
Atletas/psicologia , Enganação , Exercício Físico/psicologia , Temperatura Alta/efeitos adversos , Esforço Físico/fisiologia , Adulto , Temperatura Corporal/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Adulto Jovem
4.
Reprod Toxicol ; 30(4): 558-65, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20656018

RESUMO

Exposure of rodents in utero to perfluorooctane sulfonate (PFOS) impairs perinatal development and survival. Following intravenous or gavage exposure of C57Bl/6 mouse dams on gestational day (GD) 16 to (35)S-PFOS (12.5mg/kg), we determined the distribution in dams, fetuses (GD18 and GD20) and pups (postnatal day 1, PND1) employing whole-body autoradiography and liquid scintillation counting. In dams, levels were highest in liver and lungs. After placental transfer, (35)S-PFOS was present on GD18 at 2-3 times higher levels in lungs, liver and kidneys than in maternal blood. In PND1 pups, levels in lungs were significantly higher than in GD18 fetuses. A heterogeneous distribution of (35)S-PFOS was observed in brains of fetuses and pups, with levels higher than in maternal brain. This first demonstration of substantial localization of PFOS to both perinatal and adult lungs is consistent with evidence describing the lung as a target for the toxicity of PFOS at these ages.


Assuntos
Ácidos Alcanossulfônicos/farmacocinética , Poluentes Ambientais/farmacocinética , Fluorocarbonos/farmacocinética , Exposição Materna , Troca Materno-Fetal , Ácidos Alcanossulfônicos/sangue , Animais , Animais Recém-Nascidos/sangue , Animais Recém-Nascidos/metabolismo , Encéfalo/metabolismo , Poluentes Ambientais/sangue , Feminino , Sangue Fetal/química , Feto/metabolismo , Fluorocarbonos/sangue , Rim/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Contagem de Cintilação , Radioisótopos de Enxofre , Distribuição Tecidual , Imagem Corporal Total
5.
Ned Tijdschr Geneeskd ; 148(47): 2334-8, 2004 Nov 20.
Artigo em Holandês | MEDLINE | ID: mdl-15587053

RESUMO

Two men, aged 32 and 40, had a high-pressure paint injection injury to the left index and middle finger respectively. The first patient's finger became inflamed within a week, after which the paint was removed operatively; there was complete recovery of function. In the other patient the paint was removed immediately; however the finger was amputated a week later because of gangrene. High-pressure injection injuries should not be underestimated. High-pressure injection injuries to the hand often lead to severe and irreversible loss of function. Acknowledging the severity of this type of injury is the key to adequate treatment. Mostly this means immediate operative intervention. Only injuries with clean water, air or a small amount of vaccine can be treated conservatively under close observation.


Assuntos
Acidentes de Trabalho , Traumatismos dos Dedos/induzido quimicamente , Corpos Estranhos/cirurgia , Traumatismos da Mão/induzido quimicamente , Substâncias Perigosas/efeitos adversos , Pintura/efeitos adversos , Adulto , Desbridamento , Traumatismos dos Dedos/patologia , Traumatismos dos Dedos/cirurgia , Corpos Estranhos/diagnóstico , Gangrena/etiologia , Gangrena/cirurgia , Mãos , Traumatismos da Mão/patologia , Traumatismos da Mão/cirurgia , Humanos , Injeções/efeitos adversos , Masculino , Pressão
6.
J Hand Surg Br ; 24(4): 482-5, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10473163

RESUMO

We report a sporadic case of tetramelic mirror-image polydactyly in combination with unilateral tibial aplasia. No chromosomal or other associated abnormalities were found. The appearance and function of the upper and lower limbs were improved by surgery.


Assuntos
Anormalidades Múltiplas/cirurgia , Dedos/anormalidades , Deformidades Congênitas da Mão/cirurgia , Polidactilia/cirurgia , Tíbia/anormalidades , Dedos do Pé/anormalidades , Humanos , Masculino
7.
Ann Plast Surg ; 37(3): 278-85, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8883726

RESUMO

Vascular birthmarks are common lesions that can be divided into hemangiomas and vascular malformations (arterial, venous, capillary, and lymphatic malformations or a combination of these, according to Mulliken. Thirty-four patients with a vascular malformation were evaluated prospectively with magnetic resonance imaging (MRI) during a 6-year period in a combined study of the departments of radiology and plastic and reconstructive surgery. Hemangiomas were not part of this study, as they regress spontaneously in childhood. MRI and angiographic findings are described and the value of MRI is investigated for its usefulness in conjunction with angiography. MRI turns out to be superior as the initial diagnostic test for vascular malformations. Further investigations are not necessary in low-flow lesions. In case of high-flow and combined-flow lesions, angiography is indicated following MRI to show the exact angioarchitecture, which is essential for therapy planning. A flowchart, based on radiodiagnostic features, is proposed for diagnostic evaluation of patients with vascular birthmarks.


Assuntos
Malformações Arteriovenosas/diagnóstico , Angiografia Cerebral/métodos , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Malformações Arteriovenosas/cirurgia , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Hemangioma/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
8.
Free Radic Res Commun ; 9(3-6): 267-78, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2167265

RESUMO

Studies documenting spin trapping of lipid radicals in defined model systems have shown some surprising solvent effects with the spin trap DMPO. In aqueous reactions comparing the reduction of H2O2 and methyl linoleate hydroperoxide (MLOOH) by Fe2+, hydroxyl (HO.) and lipid alkoxyl (LO.) radicals produce identical four-line spectra with line intensities 1:2:2:1. Both types of radicals react with commonly-used HO. scavengers, e.g. with ethanol to produce .C(CH3)HOH and with dimethylsulfoxide (DMSO) to give .CH3. However, DMSO radicals (either .CH3 or .OOCH3) react further with lipids, and when radicals are trapped in these MLOOH systems, multiple adducts are evident. When acetonitrile is added to the aqueous reaction systems in increasing concentrations, .CH2CN radicals resulting rom HO. attack on acetonitrile are evident, even with trace quantities of that solvent. In contrast, little, if any reaction of LO. with acetonitrile occurs, even in 100% acetonitrile. A single four-line signal persists in the lipid systems as long as any water is present, although the relative intensity of the two center lines decreases as solvent-induced changes gradually dissociate the nitrogen and beta-hydrogen splitting constants. Extraction of the aqueous-phase adducts into ethyl acetate shows clearly that the identical four-line spectra in the H2O2 and MLOOH systems arise from different radical species in this study, but the lack of stability of the adducts to phase transfer may limit the use of this technique for routine adduct identification in more complex systems. These results indicate that the four-line 1:2:2:1, aN = aH = 14.9 G spectrum from DMPO cannot automatically be assigned to the HO. adduct in reaction systems where lipid is present, even when the expected spin adducts from ethanol or DMSO appear confirmatory for HO.. Conclusive distinction between HO. and LO. ultimately will require use of 13C-labelled DMPO or HPLC-MS separation and specific identification of adducts when DMPO is used as the spin trap.


Assuntos
Álcoois , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres , Lipídeos , Solventes , Marcadores de Spin , Óxidos N-Cíclicos , Hidróxidos , Radical Hidroxila
9.
Lipids ; 23(6): 570-9, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2845221

RESUMO

Metal catalysis of membrane lipid oxidation has been thought to occur only at cell surfaces. However, conflicting observations of the pro-oxidant activity of ferric (Fe3+) vs ferrous (Fe2+) forms of various chelates have raised questions regarding this dogma. This paper suggests that the solubilities of iron complexes in lipid phases and the corresponding abilities to initiate lipid oxidation there, either directly or via Fenton-like production of reactive hydroxyl radicals, are critical determinants of initial catalytic effectiveness. Partitioning of Fe3+ and Fe2+ complexes and chelates into bulk phases of purified lipids was quantified by atomic absorption spectroscopy. mM solutions of iron salts partitioned into oleic acid at levels of about micromolar. Ethylenediamine tetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA) chelates were somewhat less soluble, while adenosine diphosphate (ADP) chelates, and ferrioxamine were soluble as chelates at greater than 10(-5) M. Solubilities of all iron compounds in methyl linoleate were 10- to 100-fold lower. To determine whether Fenton-like reactions occur in lipid phases, H2O2 and either Fe2+ or Fe3+ and a reducing agent were partitioned into the lipid along with the spin-trap 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), and free radical adducts were recorded by electron paramagnetic resonance (EPR). Hydroxyl radicals (OH.) adducts were observed in oleic acid, but in lipid esters secondary peroxyl radicals predominated, and the presence of OH. adducts was uncertain.


Assuntos
Radicais Livres , Hidróxidos/metabolismo , Ferro/metabolismo , Metabolismo dos Lipídeos , Catálise , Membrana Celular/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Radical Hidroxila , Cinética , Lipídeos de Membrana/metabolismo , Modelos Químicos , Oxirredução , Solubilidade
11.
J Free Radic Biol Med ; 2(4): 237-43, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3034996

RESUMO

It is common practice in biochemical research to assume that iron bound to desferrioxamine (DFO) to form ferrioxamine (FOA) has been rendered inactive to subsequent redox chemistry within the range of physiological redox potentials, both in vitro and in vivo. However, plants and microorganisms can make iron metabolically available from ferrioxamine and closely related trihydroxamate siderophores, and at neutral pH, cyclic voltammetry of FOA demonstrates a reversible one-electron reduction at about -0.42 to -0.45 V (vs. normal hydrogen electrode), which is within the range of a number of reducing enzymes. We present evidence for the Fenton-like ability of FOA reduced by paraquat cation radicals to consume H2O2 and produce hydroxyl radicals (OH.) in the process. Similar reactions may explain previously reported potentiation of the oxidizing toxicity of paraquat in rats by high doses of DFO, as well as several other examples of prooxidant actions of DFO in vivo. We present the hypothesis that biphasic antioxidant/prooxidant behavior of DFO as a function of dose may be common with iron-catalyzed oxidizing reactions when mobile strong reducing agents are present. Hence, the real possibility of amplifying oxidizing damage must be considered when planning treatment with DFO, and failure of DFO to inhibit a particular response to oxidizing stress or its enhancement by DFO cannot, by itself, be considered sufficient evidence to rule out an iron-dependent process.


Assuntos
Desferroxamina , Compostos Férricos , Hidróxidos , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres , Peróxido de Hidrogênio , Radical Hidroxila , Ferro , Oxirredução , Paraquat
12.
J Free Radic Biol Med ; 1(1): 71-82, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3013974

RESUMO

The feasibility of using desferrioxamine (DF), an iron chelator, as a therapeutic agent against paraquat (PQ++) toxicity in male Sprague-Dawley rats was explored, based on the rationale of limiting toxic hydroxyl radical production from hydrogen peroxide by removing redox-active iron. Body weights, mortality, and lung histopathology were followed for periods up to 14 days after intraperitoneal injection of PQ++ (20 or 25 mg/kg body weight) with or without concurrent daily subcutaneous injections of DF (300 mg/day). Animals receiving PQ++ showed the expected typical patterns of mortality and of lung histopathology, namely: marked edema, subpleural hemorrhage, acute inflammation, perivascular mononuclear cell infiltrates, sloughing of alveolar and bronchiolar lining cells, and diffuse interstitial fibrosis. Desferrioxamine alone was non-toxic. Surprisingly, results when both PQ++ and DF were administered indicated a failure of DF to ameliorate toxic effects of PQ++ in the lung, and even suggested an accentuation of PQ++-induced damage by DF. Mortality data showed that PQ++/DF animals died in greater numbers (20 mg PQ++/kg) or died earlier (25 mg PQ++/kg) than animals receiving DF alone. Qualitative histopathology in PQ++/DF animals was comparable to PQ++ animals in early stages, but damage was more severe in both incidence and severity of lesions in PQ++/DF animals, particularly at the 25 mg PQ++/kg dose level. After 14 days, surviving animals receiving PQ++ alone showed almost complete resolution of previous inflammation and other acute effects, whereas in the only surviving PQ++/DF animal initial fibrosis had persisted and become more generalized. Thus, chelation therapy with DF may not be straightforward in its effects on PQ++ toxicity.


Assuntos
Desferroxamina/farmacologia , Paraquat/toxicidade , Animais , Quelantes/farmacologia , Desferroxamina/metabolismo , Peróxido de Hidrogênio/metabolismo , Hidróxidos , Radical Hidroxila , Ferro/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Paraquat/metabolismo , Ratos , Ratos Endogâmicos
15.
J Immunol Methods ; 17(3-4): 365-71, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-410892

RESUMO

A method for quantitating peripheral blood B cells is described which utilizes anti-heavy chain specific antibody attached to polyacrylamide beads. The method has the advantages of ease of performance, of utilizing reagents which are commercially available and routine phase microscopy. In addition, the reagents are stable for prolonged periods of time and only small amounts are required. Utilizing this assay, the following percentages of B cells have been found in normals: IgG 6.3 +/- 0.6; IgM 4.3 +/- 0.5; IgA 4.0 +/- 0.5. The polyacrylamide beads may be phatocytized allowed recognition of certain phagocytic mononuclear cells.


Assuntos
Acrilamidas , Linfócitos B , Cadeias Pesadas de Imunoglobulinas , Agamaglobulinemia/imunologia , Contagem de Células Sanguíneas , Humanos , Fagocitose , Formação de Roseta , Linfócitos T
19.
Proc Natl Acad Sci U S A ; 71(3): 994-8, 1974 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16592150

RESUMO

One-electron oxidation of zinc tetraphenylbacteriochlorin and its metal-free base yielded stable cation radicals. Electron spin resonance hyperfine splittings were assigned by selective deuterations. These results indicate that the protons of the saturated rings of the bacteriochlorins carry large spin densities, in accord with molecular orbital calculations. Comparison in vitro of the optical spectra of bacteriochlorins and their cation radicals with those of bacteriochlorophyll show close correspondence and suggest that the electron spin resonance data from the former may also prove a guide to the biological molecule. The surprising similarity in properties between the radicals of free base and zinc bacteriochlorins is maintained in the chlorophylls: cation radicals of bacteriopheophytin and methyl pheophorbide (the free bases of bacteriochlorophyll and methyl chlorophyllide, respectively) exhibit electron spin resonance properties similar to those of their magnesium-containing derivatives. The possibility that metal-free chlorophylls participate in photosynthesis is discussed.

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