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1.
J Mater Chem B ; 10(23): 4501-4508, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35615958

RESUMO

Peroxynitrite anion (ONOO-), a product derived from reaction between reactive oxygen species (ROS) and nitric oxide (NO), is considered to be a more toxic reactive species than most ROS for cancer photodynamic therapy (PDT). To promote the PDT effect, a viable method is to develop rational strategies for efficient ONOO- generation at targeted tumor sites. Herein, a heterostructure nanocomposite containing ZnO-coated lanthanide nanoparticles (LnNPs) is reported for ONOO--based PDT. In this nanocomposite, Nd3+-doped LnNPs are employed to realize efficient NIR-light-triggered ROS generation by activating the triplet state of chlorin-e6 (Ce6) photosensitizers via a direct lanthanide-to-triplet sensitization mechanism. Meanwhile, ZnO in the composite catalyzes the decomposition of S-nitrosoglutathione (GSNO) to generate NO in the tumor microenvironment. The coupled system allows the combination of photo-induced ROS and NO to produce ONOO-, leading to drastically promoted cancer cell apoptosis and tumor growth inhibition. This study establishes a new apoptosis-inducing PDT agent, which is potentially active in drug resistant malignancies.


Assuntos
Elementos da Série dos Lantanídeos , Nanopartículas Metálicas , Neoplasias , Fotoquimioterapia , Óxido de Zinco , Ânions/uso terapêutico , Humanos , Elementos da Série dos Lantanídeos/farmacologia , Elementos da Série dos Lantanídeos/uso terapêutico , Neoplasias/tratamento farmacológico , Ácido Peroxinitroso , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio , Microambiente Tumoral
2.
Molecules ; 26(4)2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33670378

RESUMO

Biodegradable and antimicrobial waterborne polyurethane dispersions (PUDs) and their casted solid films have recently emerged as important alternatives to their solvent-based and non-biodegradable counterparts for various applications due to their versatility, health, and environmental friendliness. The nanoscale morphology of the PUDs, dispersion stability, and the thermomechanical properties of the solid films obtained from the solvent cast process are strongly dependent on several important parameters, such as the preparation method, polyols, diisocyanates, solid content, chain extension, and temperature. The biodegradability, biocompatibility, antimicrobial properties and biomedical applications can be tailored based on the nature of the polyols, polarity, as well as structure and concentration of the internal surfactants (anionic or cationic). This review article provides an important quantitative experimental basis and structure evolution for the development and synthesis of biodegradable waterborne PUDs and their solid films, with prescribed macromolecular properties and new functions, with the aim of understanding the relationships between polymer structure, properties, and performance. The review article will also summarize the important variables that control the thermomechanical properties and biodegradation kinetics, as well as antimicrobial and biocompatibility behaviors of aqueous PUDs and their films, for certain industrial and biomedical applications.


Assuntos
Anti-Infecciosos/química , Plásticos Biodegradáveis/química , Polímeros/química , Poliuretanos/química , Ânions/química , Ânions/uso terapêutico , Anti-Infecciosos/uso terapêutico , Plásticos Biodegradáveis/uso terapêutico , Humanos , Polímeros/uso terapêutico , Poliuretanos/uso terapêutico , Solventes/química , Tensoativos/química , Tensoativos/uso terapêutico , Água/química
3.
J Mater Chem B ; 8(36): 8189-8206, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32812616

RESUMO

Polyoxometalates (POMs) as a kind of molecular metal-oxide cluster with precise chemical composition and architecture have been demonstrated to show potential in multidisciplinary materials. Accompanied by their bioactivities, POM clusters have also been shown to be capable of sensing diseases and allowing synergistic therapy based on their redox and near infrared absorption. In parallel with metal nanoparticles and organic materials, these inorganic clusters have also displayed unique photothermal imaging and therapeutic properties over recent years. In this review, we outlined the main achievements of POMs in the fields of bio-detecting probes and the photothermal effect. Fluorescence detection, magnetic resonance, computed tomography, and photothermal property-supported photoacoustic imaging acting as a multifunction platform that integrates photothermal therapy (PTT) were discussed at the same time. The comparison of nanocomposites to POMs alone in imaging-guided PTT, multi-modal imaging, and the combination of PTT with controlled chemotherapy and gas therapy were described in detail. The advantages and possible drawbacks of POMs as well as perspectives in related areas were analyzed, which ascertained such clusters to be a type of promising agent in biomedical applications.


Assuntos
Ânions/uso terapêutico , Meios de Contraste/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Polieletrólitos/uso terapêutico , Animais , Ânions/química , Ânions/efeitos da radiação , Linhagem Celular Tumoral , Meios de Contraste/química , Meios de Contraste/efeitos da radiação , Humanos , Raios Infravermelhos , Técnicas Fotoacústicas/métodos , Terapia Fototérmica/métodos , Polieletrólitos/química , Polieletrólitos/efeitos da radiação , Tomografia Computadorizada por Raios X/métodos
4.
Aust Vet J ; 96(7): 269-273, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29944750

RESUMO

BACKGROUND: Adjusting the dietary cation-anion difference (DCAD) is one of the most efficient ways to stimulate calcium homeostasis in periparturient dairy cattle. However, adjusting DCAD to the recommended negative values (-100 to -150 mEq/kg) is associated with decreased food intake and metabolic acidosis. The critical conditions of the animals at peripartum (i.e. drastic hormonal changes, decreased appetite and negative energy balance) can be detrimental to the health, productivity and welfare of the animals if combined with decreased feed intake caused by unpalatable acidogenic salts. METHODS: In a cross-sectional study, we analysed the ration of eight small to large dairy herds with intensive husbandry systems, including 6949 dry cows. Sodium, potassium, chlorine and sulfur concentrations in the feed were determined and DCAD was calculated. The DCAD of the ration of the farms ranged from -33.5 to +24.7 mEq/kg. Parturient paresis (PP, or milk fever) prevalence was investigated and correlated to DCAD values. RESULTS: Clinical PP occurrence in the dairies of this investigation on average declined by 87% (ranging from a 97% decline to 5% increase). This indicates that adjusting DCAD at neutral values (0 ± 30 mEq/kg range) may both lower the PP prevalence and increase ration palatability by lowering acidogenic salts in the ration. CONCLUSIONS: Further research is recommended to investigate the effects of neutral DCAD on subclinical hypocalcaemia and food intake of the cattle.


Assuntos
Ração Animal/análise , Ânions/uso terapêutico , Cátions/uso terapêutico , Hipocalcemia/veterinária , Paresia Puerperal/dietoterapia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Ânions/análise , Cátions/análise , Bovinos , Cloro/análise , Cloro/uso terapêutico , Estudos Transversais , Indústria de Laticínios , Dieta , Feminino , Hipocalcemia/dietoterapia , Lactação , Potássio/análise , Potássio/uso terapêutico , Gravidez , Sódio/análise , Sódio/uso terapêutico , Inquéritos e Questionários
5.
J Wound Care ; 22(3): 144-6, 148, 150-2 passim, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23665733

RESUMO

OBJECTIVE: To compare the efficacy and safety of negatively-charged polystyrene microspheres (NCM)with controls (saline soaks) in the treatment of hard-to-heal wounds of various aetiologies. METHOD: Patients with one or more hard-to-heal wounds, defined as refractory to healing for at least 4 weeks, or those with exposed bone, tendon or ligament, were eligible for inclusion and were randomised to either NCM (PolyHeal; MediWound Ltd.) or controls, both applied twice daily for 4 weeks. Patients were monitored bi-weekly for an additional 8 weeks, while treated by standard wound care, at the investigators' discretion, and were re-evaluated 2 years after inclusion. The primary endpoint was defined as coverage of> 75% of the wound area by light-red granulation tissue after 4 weeks of treatment. RESULTS: Fifty-eight patients completed the study, 32 in the NCM group and 26 in the control group. The two most common wound types were those with primary etiologies of venous insufficiency and postoperative/post trauma. In the NCM group 47% of patients achieved > 75% light red granulation tissue after 4 weeks compared with 15% of patients in the control group (p=O.O I). The mean wound surface area in the NCM group was reduced by 39.0% after 4 weeks compared with 14.9% in the control group (p=0.02).The achievement of> 75% light red granulation tissue and reduction of mean wound surface area was also observed in the two main sub-groups (venous insufficiency and postoperative/post trauma), although it was not statistically significant, possibly due to the small sample size in each sub-group. CONCLUSION: This study demonstrates that compared to control treatment, NCM treatment of hard to-heal and chronic wounds improves formation of healthy granulation tissue and reduces wound size thus in fact 'kick-starting' the healing process and 'dechronifying' chronic wounds.


Assuntos
Ânions/uso terapêutico , Tecido de Granulação/crescimento & desenvolvimento , Microesferas , Úlcera Cutânea/terapia , Cicatrização , Adulto , Idoso , Doença Crônica , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Poliestirenos , Estudos Prospectivos , Solução Salina Hipertônica , Eletricidade Estática , Resultado do Tratamento
6.
Cochrane Database Syst Rev ; (9): CD002986, 2012 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-22972060

RESUMO

BACKGROUND: Previous reports have shown that ion content in the air may have an effect on respiratory function. Results from studies which test the efficacy of air ionisers to reduce asthma symptoms are often inconclusive and their use as a treatment for asthma remains debatable. OBJECTIVES: We conducted a systematic review of the available evidence to determine the effectiveness of positive and negative ion generators in people with asthma. SEARCH METHODS: We searched the Cochrane Airways Group Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL) as well as the alternative medicine database AMED. Searches were current as of June 2012. SELECTION CRITERIA: Randomised controlled trials (parallel or crossover design studies) comparing ionisers with dummy ionisers (being negative or positive ion emitters), in children or adults with chronic asthma. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed titles and abstracts of studies and assessed trial quality. Study quality was determined using two methods:The Cochrane approach to allocation concealment and the five point Jadad scale. MAIN RESULTS: Six studies were selected for inclusion (106 participants). No results were combined as the studies were all of a crossover design.EFFECTS OF NEGATIVE ION GENERATORS (five studies) No study reported a significant difference in lung function between ionised and control air (morning Peak expiratory flow (PEF) - three studies; forced expiratory flow in one second (FEV1) - one study). There were no significant differences in symptoms or beta-2 agonist usage between ionised and control air in three studies.EFFECTS OF POSITIVE ION GENERATORS (one study) This study demonstrated that although positively ionised air was associated with a larger fall in FEV1 with exercise, this did not reach statistical significance. Baseline FEV1 was not demonstrated to be significantly different between treatment groups. AUTHORS' CONCLUSIONS: Based on the evidence currently available from randomised controlled trials, a recommendation cannot be given for the use of room air ionisers to reduce symptoms in patients with chronic asthma.


Assuntos
Ionização do Ar , Asma/terapia , Adolescente , Adulto , Ânions/uso terapêutico , Cátions/uso terapêutico , Criança , Pré-Escolar , Estudos Cross-Over , Humanos , Lactente , Íons/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto Jovem
7.
Psychiatry Res ; 196(1): 57-61, 2012 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-22424890

RESUMO

Treatment of bipolar disorder often results in patients taking several drugs in an attempt to alleviate residual depressive symptoms, which can lead to an accumulation of side effects. New treatments for bipolar depression that do not increase the side effect burden are needed. One nonpharmacological treatment with few side effects, bright light therapy, has been shown to be an effective therapy for seasonal affective disorder, yet has not been extensively studied for other forms of depression. Forty-four adults with bipolar disorder, depressed phase were randomized to treatment with bright light therapy, low-density or high-density negative ion generator for 8 weeks. The primary measure of efficacy was the Structured Interview Guide for the Hamilton Depression Rating Scale with Atypical Depression Supplement (SIGH-ADS). Adverse events were assessed using the Young Mania Rating Scale (YMRS) and Systematic Assessment for Treatment Emergent effects (SAFTEE). All outcome variables were statistically analyzed using a mixed model repeated measure analysis of variance (ANOVA). The results showed no statistically significant differences between groups in any outcome measures at study end point; adverse events, including switches into hypomania, were rare. Further research is needed to determine the efficacy of bright light therapy in this population.


Assuntos
Ânions/uso terapêutico , Transtorno Bipolar/terapia , Fototerapia/psicologia , Adulto , Ânions/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fototerapia/efeitos adversos , Fototerapia/instrumentação , Fototerapia/métodos , Escalas de Graduação Psiquiátrica/estatística & dados numéricos
8.
Psychol Med ; 42(8): 1605-12, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22152099

RESUMO

BACKGROUND: Antidepressant drug treatments increase the processing of positive compared to negative affective information early in treatment. Such effects have been hypothesized to play a key role in the development of later therapeutic responses to treatment. However, it is unknown whether these effects are a common mechanism of action for different treatment modalities. High-density negative ion (HDNI) treatment is an environmental manipulation that has efficacy in randomized clinical trials in seasonal affective disorder (SAD). METHOD: The current study investigated whether a single session of HDNI treatment could reverse negative affective biases seen in seasonal depression using a battery of emotional processing tasks in a double-blind, placebo-controlled randomized study. RESULTS: Under placebo conditions, participants with seasonal mood disturbance showed reduced recognition of happy facial expressions, increased recognition memory for negative personality characteristics and increased vigilance to masked presentation of negative words in a dot-probe task compared to matched healthy controls. Negative ion treatment increased the recognition of positive compared to negative facial expression and improved vigilance to unmasked stimuli across participants with seasonal depression and healthy controls. Negative ion treatment also improved recognition memory for positive information in the SAD group alone. These effects were seen in the absence of changes in subjective state or mood. CONCLUSIONS: These results are consistent with the hypothesis that early change in emotional processing may be an important mechanism for treatment action in depression and suggest that these effects are also apparent with negative ion treatment in seasonal depression.


Assuntos
Ionização do Ar , Emoções , Transtorno Afetivo Sazonal/terapia , Adulto , Afeto , Análise de Variância , Ânions/uso terapêutico , Método Duplo-Cego , Expressão Facial , Feminino , Humanos , Masculino , Testes Neuropsicológicos/estatística & dados numéricos , Placebos , Escalas de Graduação Psiquiátrica , Tempo de Reação , Reconhecimento Psicológico/fisiologia , Transtorno Afetivo Sazonal/psicologia , Resultado do Tratamento
9.
J Vet Med Sci ; 69(3): 265-70, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17409642

RESUMO

In our previous study, it was demonstrated that the administration of anion salts, which slightly lower the dietary cation-anion difference (DCAD), in the prepartum period is safe and effective for preventing milk fever in multiparous cows. In the present study, several biomarkers, which might show activation of Ca metabolism, were analyzed using stored samples in the previous study to investigate the mechanism of the preventive effect on milk fever by lowering DCAD. Changes in bone-specific alkaline phosphatase activity, osteocalcin and insulin-like growth factor I concentrations in serum were almost the same among the three groups of multiparous cows with or without the oral administration of anion salts, while the levels of these serum biomarkers in the group of primiparous cows (heifer group) were much higher compared with those in the three multiparous groups throughout the experimental period. Urinary deoxypyridinoline excretion was not a useful biomarker for dairy cows because it hardly changed during the peripartum period in all groups. However, serum tartrate-resistant acid phosphatase (TRAP) activity, which is known as a biomarker of osteoclast activity, was well associated with the administration of anion salts lowering DCAD because among the three multiparous groups, only the group of multiparous cows fed the anion salts (anion group) showed an increased level, which rose to the level in the heifer group, and was markedly higher than those in the other control groups of multiparous cows. The increased activity of serum TRAP in the anion group suggested that Ca in the plasma pool was mobilized smoothly from bone-bound Ca via mature osteoclasts at parturition, which might be due to prior activation under mild acidosis induced by slightly lowering DCAD. Therefore, TRAP was the best biomarker to monitor the activation of Ca metabolism in dairy cows fed anion salts.


Assuntos
Fosfatase Ácida/metabolismo , Ânions/uso terapêutico , Osso e Ossos/metabolismo , Cálcio/metabolismo , Doenças dos Bovinos/prevenção & controle , Isoenzimas/metabolismo , Paresia Puerperal/prevenção & controle , Fosfatase Alcalina/metabolismo , Animais , Ânions/metabolismo , Biomarcadores/metabolismo , Cátions/metabolismo , Bovinos , Doenças dos Bovinos/dietoterapia , Doenças dos Bovinos/metabolismo , Feminino , Fator de Crescimento Insulin-Like I/metabolismo , Osteocalcina/sangue , Paresia Puerperal/dietoterapia , Paresia Puerperal/metabolismo , Gravidez , Fosfatase Ácida Resistente a Tartarato
12.
Am J Vet Res ; 65(8): 1071-6, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15334840

RESUMO

OBJECTIVE: To compare plasma total calcium, phosphorus, magnesium, nonesterified fatty acids (NEFA), beta hydroxy butyrate (BHB), and glucose concentrations in parturient dairy cows that were fed an anionic prepartum diet between those with and without retained fetal membranes (RFM) at 24 hours after parturition. ANIMALS: 152 Holstein cows that calved during October through December of 1997 PROCEDURE: All cows were fed an anionic prepartum diet. Blood sample was taken within 6 hours after parturition from randomly selected cows. Thirty-nine cows had a diagnosis of RFM at 24 hours after parturition; 113 were not affected with RFM. At calving, body condition score (BCS; 1 [thin] to 5 [obese]), parity, and calving difficulty score were recorded. Plasma calcium, phosphorus, magnesium, NEFA, BHB, and glucose concentrations were compared between cows with or without RFM. RESULTS: Cows with RFM had significantly lower plasma calcium concentration soon after calving, compared with cows without RFM. Cows with a parity of > or = 3 had significantly lower plasma concentrations of calcium and higher concentrations of magnesium, compared with cows with a parity of 1 or 2. Cows with a BCS of > or = 3.25 at calving had significantly higher plasma concentrations of BHB than cows with a BCS of 2.75 to 3.0. Cows with dystocia had significantly higher plasma concentrations of glucose, compared with cows without dystocia. CONCLUSIONS AND CLINICAL RELEVANCE: In parturient cows fed a prepartum anionic diet, those with RFM have lower plasma calcium concentrations than cows without RFM, although this association does not prove a cause-effect relationship.


Assuntos
Cálcio/sangue , Doenças dos Bovinos/sangue , Membranas Extraembrionárias/patologia , Complicações na Gravidez/veterinária , Análise de Variância , Animais , Ânions/uso terapêutico , Análise Química do Sangue , Bovinos , Doenças dos Bovinos/dietoterapia , Doenças dos Bovinos/etiologia , Colorimetria , Indústria de Laticínios , Feminino , Minerais/sangue , Gravidez , Complicações na Gravidez/dietoterapia , Complicações na Gravidez/etiologia , Espectrofotometria Atômica
13.
Cochrane Database Syst Rev ; (3): CD002986, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12917939

RESUMO

BACKGROUND: Previous reports have shown that ion content in the air may have an effect on respiratory function. Results from studies which test the efficacy of air ionisers to reduce asthma symptoms are often inconclusive and their use as a treatment for asthma remains debatable. OBJECTIVES: We conducted a systematic review of the available evidence to determine the effectiveness of positive and negative ion generators in people with asthma. SEARCH STRATEGY: We searched the Cochrane Airways Group Asthma trials register (January 1966 to March 2003), Cochrane Central Register of Controlled Trials (Cochrane Library issue 2, 2003) as well as The Alternative Medicine Database AMED (1985 to March 2003). SELECTION CRITERIA: Randomised controlled trials (parallel or crossover design studies) comparing ionisers with dummy ionisers (being negative or positive ion emitters), in children or adults with chronic asthma. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed titles and abstracts of studies and assessed trial quality. Study quality was determined using two methods:The Cochrane approach to allocation concealment and the five point Jadad scale. MAIN RESULTS: Six studies were selected for inclusion (106 participants). No results were combined as the studies were all of a crossover design. EFFECTS OF NEGATIVE ION GENERATORS (five studies)No study reported a significant difference in lung function between ionised and control air (morning Peak expiratory flow (PEF) - three studies; forced expiratory flow in one second (FEV1) - one study). There were no significant differences in symptoms or beta-2 agonist usage between ionised and control air in three studies. EFFECTS OF POSITIVE ION GENERATORS (one study)This study demonstrated that although positively ionised air was associated with a larger fall in FEV1 with exercise, this did not reach statistical significance. Baseline FEV1 was not demonstrated to be significantly different between treatment groups. REVIEWER'S CONCLUSIONS: Based on the evidence currently available from randomised controlled trials, a recommendation cannot be given for the use of room air ionisers to reduce symptoms in patients with chronic asthma.


Assuntos
Ionização do Ar , Asma/terapia , Íons/uso terapêutico , Adulto , Ânions/uso terapêutico , Cátions/uso terapêutico , Criança , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Transpl Int ; 15(1): 17-23, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11875608

RESUMO

In liver preservation, the substitution of the anion Cl(-) by lactobionic acid (LB) prevents reperfusion edema and extends the preservation time for human livers. We studied the effect of compounds that are structurally related to lactobionic acid: anionic polycarbohydrates (sulfated anionic polysaccharide, SAP, and pentosan polysulfate, PPS) on liver function and leukocyte-endothelial cell interaction in isolated perfusion and liver transplant models. Rat livers, cold-stored (24 h) in a Cl(-) -containing control solution, became edematous during 1 h of reperfusion. Substitution of Cl(-) by either LB, SAP, or PPS decreased reperfusion edema in a Cl(-) concentration-dependent fashion. Reperfusion edema was abolished completely after preservation in 100 mM SAP solution or PPS solution. Also hepatic lactic dehydrogenase (LDH) and aspartate aminotransferase (ASAT) release was lowest after preservation in those solutions. After preservation in LB or anionic polycarbohydrate solutions, portal venous resistance was significantly higher than after preservation in Cl(-)-containing control solution. Capillary blood flow was 391 +/- 83 pl/s and 398 +/- 174 pl/s after preservation in SAP solution (SAPs) and PPSs, and 803 +/- 117 pl/s and 641 +/- 219 pl/s after preservation in LB or Cl(-)-containing control solution. The number of leukocytes sticking to the vascular wall was lower ( P < 0.05) after preservation in SAPs or PPSs (109 +/- 31 cells/mm(2) and 108 +/- 60 cells/mm(2), respectively), when compared with preservation in Cl(-)-containing control or LB solutions (429 +/- 63 cells/mm(2) and 277 +/- 59 cells/mm(2)). In rat liver preservation, anionic polysaccharides are antiedematous compounds, with a higher potency than LB and additional antiadhesive properties.


Assuntos
Fígado/efeitos dos fármacos , Soluções para Preservação de Órgãos/análise , Soluções para Preservação de Órgãos/uso terapêutico , Polissacarídeos/análise , Polissacarídeos/uso terapêutico , Aderências Teciduais/prevenção & controle , Adenosina/análise , Alopurinol/análise , Animais , Ânions/análise , Ânions/uso terapêutico , Sequência de Carboidratos , Dissacarídeos/análise , Dissacarídeos/uso terapêutico , Glutationa/análise , Técnicas In Vitro , Insulina/análise , Fígado/irrigação sanguínea , Fígado/citologia , Fígado/cirurgia , Masculino , Microscopia de Fluorescência , Microscopia de Vídeo/métodos , Soluções para Preservação de Órgãos/classificação , Perfusão , Rafinose/análise , Ratos , Ratos Endogâmicos Lew , Ratos Wistar
15.
Adv Drug Deliv Rev ; 53(1): 109-22, 2001 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-11733120

RESUMO

Responsive hydrophobically associating polymers can in many ways be considered to be analogous to proteins in their ability to form compact molecules with a defined secondary structure, and hence, functionality. These molecules are characterized by the presence of alternating charged and hydrophobic groups. The balance between charge repulsion and hydrophobic interactions is sensitive to environmental pH and therefore changes in pH produce controllable conformational changes. The change from a charged extended chain to a collapsed uncharged coil structure is sometimes referred to as hypercoiling behaviour and enables the polymer to act as a simple switch between an 'on' and 'off' state. The purpose of this review is to illustrate the structure and behaviour of polymers that exhibit hypercoiling behaviour and to highlight their potential pharmaceutical applications, which in terms of drug delivery is likely to be related to their surface behaviour and solubilizing activity.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Polímeros/química , Animais , Ânions/química , Ânions/uso terapêutico , Cátions/química , Cátions/uso terapêutico , Humanos , Conformação Molecular , Polímeros/uso terapêutico , Soluções , Relação Estrutura-Atividade , Propriedades de Superfície
16.
Harv Ment Health Lett ; 15(12): 6, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10233799
18.
Rev. bras. odontol ; 47(5): 46-51, set.-out. 1990. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-857359

RESUMO

Através de minuciosa revista da literatura, os autores estudaram a etapa da limpeza cavitária, suas indicações, técnicas e soluções utilizadas. Discutem a camada de "smear", suas implicações e sua remoção. Baseados nas sugestões da literatura e na experiência clínica, sugerem uma técnica de limpeza com detergente aniônico associado a uma substância que remova a camada superficial de "smear"


Assuntos
Ânions/uso terapêutico , Preparo da Cavidade Dentária/métodos
19.
J Clin Psychiatry ; 47(3): 141-3, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3949723

RESUMO

Clinical reports and animal studies support the existence of a "serotonin irritation syndrome." This is a putative anxiety state caused by a rise in atmospheric cations and reversed by a corresponding rise in anions. Volunteers were exposed to generated ambient cations and anions under controlled conditions. Cations were found to increase anxiety, excitement, and suspicion. Anions reversed the effects of cations and, in addition, reduced suspicion and excitement to levels below those occurring before cationization. Implications of these findings and the possible mediation of effects by serotonin are discussed.


Assuntos
Ionização do Ar , Ansiedade/etiologia , Serotonina/fisiologia , Ânions/uso terapêutico , Ansiedade/fisiopatologia , Ansiedade/terapia , Cátions/efeitos adversos , Humanos , Escalas de Graduação Psiquiátrica
20.
J Gen Virol ; 65 ( Pt 8): 1325-30, 1984 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6205119

RESUMO

Treatment of scrapie-infected mice with dextran sulphate (DS) 500 resulted in considerably reduced spleen titres over a long period of time. Subsequently, the central nervous system disease was delayed or even prevented during the 350-day period of observation. Both effects increased after multiple injections of the compound. The potency of DS 500 to protect against scrapie was greatest when treatment and infection were carried out simultaneously. Under these conditions the lethality of 500 to 1000 LD50 was reduced to almost zero. Treatment as early as 10 weeks before infection still prolonged the incubation periods. Of several other polyions tested, dextran sulphate 5 and pentosan polysulphate also impaired scrapie pathogenesis.


Assuntos
Scrapie/prevenção & controle , Baço/microbiologia , Replicação Viral/efeitos dos fármacos , Animais , Ânions/uso terapêutico , Sulfato de Dextrana , Dextranos/farmacologia , Dextranos/uso terapêutico , Feminino , Camundongos , Ovinos , Relação Estrutura-Atividade
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