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1.
Med Hypotheses ; 123: 118-124, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30696581

RESUMO

Inhalational anesthetics such as isoflurane, desflurane and halothane are the mainstay medications for surgical procedures; upon inhalation, they produce anesthesia described as reversible unconsciousness with the features of amnesia, sleep, immobility and analgesia. To date, how they produce anesthesia is unknown. This study proposes that carbonic anhydrase enzymes are likely targets mediating the actions of inhalational anesthetics. Carbonic anhydrase enzymes, commonly expressed in living organisms, utilize carbon dioxide (CO2) as a substrate and can generate H+ and HCO3- from CO2 with a great efficiency. There are remarkable lines of evidence for their likely roles in mediating anesthetic actions. Firstly, carbonic anhydrase enzymes are extensively expressed in the brain and spinal cord, and their importance in the brain activity, especially for the GABA and NMDA receptor signaling pathways, has been demonstrated in numerous studies. According to these studies, they provide HCO3- for GABA-A receptor activities and also buffer HCO3- excess resulting from NMDA receptor activation. Activation of GABA-A and inhibition of NMDA receptors are associated with the induction of anesthesia by the intravenous general anesthetics propofol and ketamine, respectively. Secondly, the carbonic anhydrase inhibitors topiramate and zonisamide are effectively used in the treatment of epilepsy for decades; their chronic use results in the requirement of increased levels of amobarbital in order to produce anesthesia in the epileptic patients during WADA test. In addition, given that CO2 is a substrate for these enzymes, their tertiary structure is likely has a hydrophobic pocket suitable for the anesthetic molecules to bind. Inhalational anesthetic molecules, which are lipophilic and inert in nature, have an ability to cross the membranes and inhibit carbonic anhydrases, which might not be accessible by topiramate and zonisamide. Unlike carbonic anhydrase inhibitors, they could bind to the hydrophobic pocket for CO2 molecules and produce a profound effect called anesthesia. Finally, there is a great deal of similarities between the physiological actions of inhalational anesthetics and carbonic anhydrase inhibitors; moreover well-known side effects of inhalational anesthetics could be associated with the inhibition of carbonic anhydrases. Therefore, this article presents a hypothesis that the anesthetic actions of inhalational anesthetics could be due to their inhibitory effects on the carbonic anhydrases. Investigating this hypothesis might lead to the development of new safer anesthetics, and more importantly it might reveal an endogenous anesthetic pathway, in which the carbonic anhydrase system is a component along with the GABA-A and NMDA receptor systems.


Assuntos
Anestésicos Inalatórios/farmacologia , Anidrases Carbônicas/metabolismo , Isoflurano/farmacologia , Anestesia , Animais , Encéfalo/enzimologia , Dióxido de Carbono , Humanos , Receptores de GABA-A/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Topiramato/farmacologia , Zonisamida/farmacologia
2.
J Agric Food Chem ; 61(34): 8198-206, 2013 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-23899009

RESUMO

Commercial manufacture of fruit leathers (FL) usually results in a portion of the product that is out of specification. The disposition of this material poses special challenges in the food industry. Because the material remains edible and contains valuable ingredients (fruit pulp, sugars, acidulates, etc.), an ideal solution would be to recover this material for product rework. A key practical obstacle to such recovery is that compositing of differently colored wastes results in an unsalable gray product. Therefore, a safe and scalable method for decolorization of FL prior to product rework is needed. This research introduces a novel approach utilizing ozonation for color removal. To explore the use of ozonation as a decolorization step, we first applied it to simple solutions of the commonly used food colorants 2-naphthalenesulfonic acid (Red 40), tartrazine (Yellow 5), and erioglaucine (Blue 1). Decolorization was measured by UV/vis spectrometry at visible wavelengths and with a Hunter colorimeter. Volatile and semivolatile byproducts from ozone-based colorant decomposition were identified and quantified with solid phase microextraction coupled with gas chromatography-mass spectrometry (SPME-GC-MS). Removal of Yellow 5, Red 40 and Blue 1 of about 65%, 80%, and 90%, respectively, was accomplished with 70 g of ozone applied per 1 kg of redissolved and resuspended FL. Carbonyl compounds were identified as major byproducts from ozone-induced decomposition of the food colorants. A conservative risk assessment based on quantification results and published toxicity information of potentially toxic byproducts, determined that ozone-based decolorization of FL before recycling is acceptable from a safety standpoint. A preliminary cost estimate based on recycling of 1000 tons of FL annually suggests a potential of $275,000 annual profit from this practice at one production facility alone.


Assuntos
Doces/análise , Corantes de Alimentos/química , Resíduos Industriais/análise , Ozônio/química , Reciclagem/métodos , Corantes de Alimentos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Microextração em Fase Sólida
5.
Haemophilia ; 18(1): 69-74, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21651678

RESUMO

This study was conducted to understand the pathogenetic mechanisms that are involved in the development of bone loss in children with severe haemophilia A (HA). Fourty-four children with severe HA and 40 age- and gender-matched healthy control subjects were enrolled in this study. Markers of bone remodelling and osteoclast regulation including serum bone specific alkaline phosphatase, parathormone, 25-hydroxy-vitamin D(3) (25HOvitD(3)), osteocalcin and calcitonin levels were studied. Bone mineral density (BMD) was also studied in all children. The measurement of markers of bone remodelling and osteoclast regulation suggested increased osteoclast-mediated resorption activity in children with severe HA. Although serum parathormone levels were significantly increased, serum 25HOvitD(3) and osteocalcin levels were significantly reduced. BMD was significantly reduced in severe haemophilics compared with healthy controls. There was also significant inverse correlation between BMD z-score and total joint scores, and insignificant inverse correlation between BMD z-score and single joint scores. There were also significant inverse correlation between 25HOvitD(3) and osteocalcin levels and total joint scores. Children with severe HA could have significantly reduced BMD, compared with gender- and age-matched healthy control subjects. Our results of the markers of bone remodelling and osteoclast regulation suggested that increased osteoclast-mediated resorption and decreased osteoblastic activity in children with severe HA. All children with severe HA should be routinely screened in terms of BMD.


Assuntos
Densidade Óssea/fisiologia , Hemofilia A/fisiopatologia , Adolescente , Fosfatase Alcalina/sangue , Biomarcadores/sangue , Doenças Ósseas Metabólicas/sangue , Doenças Ósseas Metabólicas/fisiopatologia , Calcifediol/sangue , Calcitonina/sangue , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Hemofilia A/sangue , Humanos , Masculino , Osteocalcina/sangue , Turquia , Adulto Jovem
6.
Haemophilia ; 16(6): 932-6, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20518818

RESUMO

Between January 2006 and December 2009, 37 radioisotope synovectomy (RS) in 18 severe haemophilic patients (factor 8<1%) have been performed at our centre. The distribution of joint injected was as follows: rhenium-186 [Re186], 19 joints (ankles, 8 and elbows, 11) and yttrium-90 [Y90] 18 joints (knees, 18). Their mean age was 12 years (range: 8-20 years). Mean follow-up period after procedure was 22.6 months. We preferred to use Y90 for all large joints and Re186 for small joints. Haemophilic patients with grade-II or III synovitis were selected for RS in our study. Radioisotope synovectomy was performed in eight ankles for seven patients, 11 elbows for seven patients and 18 knees for 13 patients. Mean bleeding counts before the procedure and after the procedure were as follows: Ankles, 3.43 vs. 0.62 (P=0.002); elbows, 3.12 vs. 0.55 (P=0.000); and 3.83 vs. 0.62 (P=0.011). No major complications requiring secondary treatments were observed. In summary, an early RS is the best way to halt the evolution of chronic haemophilia synovitis to devastating haemophilic arthropathy. Radioisotope synovectomy is very effective and safe in the treatment of chronic synovitis of children with haemophilia. Our data confirm the efficacy of RS for the treatment of chronic haemophilic synovitis, which has been previously published by many authors around the world. We highly recommend this procedure for developing countries to prevent joint disabilities. For a better and a healthier generation, RS has to be introduced in all the developing countries.


Assuntos
Hemofilia A/complicações , Sinovite/complicações , Sinovite/radioterapia , Adolescente , Adulto , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/cirurgia , Criança , Doença Crônica , Articulação do Cotovelo/diagnóstico por imagem , Articulação do Cotovelo/cirurgia , Humanos , Injeções Intra-Articulares , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Radioisótopos/uso terapêutico , Cintilografia , Rênio/uso terapêutico , Turquia , Adulto Jovem , Radioisótopos de Ítrio/uso terapêutico
7.
Bioresour Technol ; 99(11): 4943-8, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17964150

RESUMO

Dried biomass of Rhizopus oligosporus produced from food processing wastewater was used as an adsorbent for copper ions in water. The adsorption process was carried out in a batch process and the effects of contact time (1-48 h), initial pH (2.0-6.0), initial metal ion concentration (20-100 mg L(-1)) and temperature (20-38 degrees C) on the adsorption were investigated. Experimental results showed that the maximum adsorption capacity was achieved at pH 5.0 and adsorbed Cu(II) ion concentration was increased with increasing initial metal concentration and contact time. The isothermal data could be described well by the Langmuir equations and monolayer capacity had a mean value of 79.37 mg g(-1). A pseudo-second order reaction model provided the best description of the data with a correlation coefficient 0.99 for different initial metal concentrations. Thermodynamic parameters indicated that biosorption of Cu(II) on R. oligosporus dried biomass was exothermic and spontaneous. To observe the copper pellets on the biosorbent surface after biosorption SEM was used and copper was characterized by EDX. The results of FTIR analyses indicated that amide I and hydroxyl groups of adsorbent played important role in binding Cu(II).


Assuntos
Cobre/isolamento & purificação , Indústria de Processamento de Alimentos , Resíduos Industriais , Rhizopus/metabolismo , Eliminação de Resíduos Líquidos , Adsorção , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Cinética , Metais , Microscopia Eletrônica de Varredura , Rhizopus/ultraestrutura , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termodinâmica , Fatores de Tempo
8.
Clin Exp Obstet Gynecol ; 34(1): 31-4, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17447634

RESUMO

Estradiol is a steroid-structured hormone that has a periodic rhythm in the menstrual cycle. We aimed to evaluate the interference of high estradiol levels and the depth of anaesthesia. The study was performed on 44 females undergoing gynaelocologic surgery. Blood samples were performed for estradiol level before the procedures. BIS scores were recorded at 5-min intervals after induction and during the operation. Cases were assigned to three groups: Group 1 (n: 17) estradiol levels at or under 100 microg/dl, Group 2 (n: 14) levels were between 100 and 200 microg/dl and Group 3 (n: 13) levels were above 200 microg/dl. Estradiol levels were found to be 59.94 +/- 23.59 microg/dl in Group 1, 138.60 +/- 23.49 microg/dl in Group 2 and 239.30 +/- 41.08 microg/dl in Group 3. Significant differences were found between initial control and 10 and 80 min BIS levels. Anaesthetic consumption showed a decreased tendency in high estradiol cases. We concluded that an advanced clinical series should be performed to fully define the relationship between estradiol levels and anaesthesia depth.


Assuntos
Anestesia/classificação , Anestésicos/farmacocinética , Estradiol/sangue , Adulto , Eletroencefalografia , Estradiol/metabolismo , Feminino , Humanos
9.
J Hazard Mater ; 136(3): 911-6, 2006 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-16490303

RESUMO

In this study, cotton boll was used as an adsorbent for the aim of removing of the Cu(II) ions from the aqueous solutions. The adsorption process was carried out in a batch process and the effects of contact time (2-24h), adsorbent concentration (1-20 g l(-1)), initial pH (2.0-6.0), initial metal ion concentration (20-160 mg l(-1)) and temperature (20-45 degrees C) on the adsorption were investigated. Experimental results showed that the maximum adsorption capacity was determined at pH 5.0 and adsorbed Cu(II) ion concentration was increased with increasing adsorbent concentration and contact time. The isothermal data of cotton boll could be well described by the Langmuir equations and the Langmuir monolayer capacity had a mean value of 11.40 mg g(-1). Experimental results indicated that the pseudo-second order reaction model provided the best description of the data with a correlation coefficient 0.99 for different initial metal concentrations and therefore it was explained that chemical sorption was the basic mechanism in this system. FT-IR results showed that oxygen and nitrogen atoms in structure of cotton boll were involved in Cu(II) ions adsorption.


Assuntos
Cobre/química , Gossypium/química , Adsorção , Algoritmos , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termodinâmica
10.
Biodegradation ; 16(3): 195-204, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15865144

RESUMO

Decolourisation of reactive dyes Drimarene Blue X3LR and Remazol Brilliant Blue R by white rot fungi Funalia trogii was studied under static conditions. The effect of various conditions such as mycelial age, initial dye and glucose concentrations on decolourisation were also investigated. Decolourisation activity of F. trogii was compared with Phanerochaete chrysosporium known as test microorganism. It was found that 7-day-old cultures were more effective than 5-day-old cultures of F. trogii for decolourisation of these dyes. Decolourisations by F. trogii of both dyes were increased with glucose concentration decreasing. In contrast, decolourisations by P. chrysosporium were decreased. F. trogii decolourised 92-98% of both dyes within 4-10 h. However, P. chrysosporium partiallydecolourised (11-20%) these dyes during 10 days incubation period under the same conditions.


Assuntos
Antraquinonas/metabolismo , Corantes/metabolismo , Polyporaceae/metabolismo , Antraquinonas/química , Biodegradação Ambiental , Cor , Corantes/química , Glucose/metabolismo , Cinética , Estrutura Molecular , Phanerochaete/crescimento & desenvolvimento , Phanerochaete/metabolismo , Polyporaceae/crescimento & desenvolvimento , Especificidade da Espécie
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