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1.
Heterologous immunoprecipitates also have potential for therapeutic use   总被引:1,自引:0,他引:1  
Potential therapeutic usefulness of administered enzymes is limited by toxicity and allergenicity. To overcome these problems we are using scurvy to test various enzyme modifications that may be suitable for therapy. L-Gulonolactone oxidase, which catalyzes the final step in ascorbic acid biosynthesis, is immunoprecipitated with specific antisera from rabbits and then cross-linked with glutaraldehyde. The modified enzyme retains activity sufficient to elicit ascorbic acid synthesis in scorbutic guinea pigs. Intraperitoneal injection of this altered enzyme to animals supplemented with L-gulonolactone increases plasma concentrations of the vitamin. Importantly, multiple doses of the complex are tolerated. Therefore, it is possible to prolong survival time of animals fed an ascorbic acid-deficient diet by this enzyme replacement therapy. This procedure can also be applied to other enzymes that have potential therapeutic use. Serum cholinesterase and asparaginase both retain activity after this modification and are tolerated in single or in weekly repeated injections. Following three or four weekly injections, an anaphylactic reaction to serum but not to enzyme can be elicited if they are injected intravascularly. We conclude that the stability of the immobilized foreign enzyme is a critical factor in lessening the toxicity to multiple injections of these foreign proteins.  相似文献   

2.
Vascular access for extracorporeal therapy in the rabbit   总被引:1,自引:0,他引:1  
A technique allowing short-term blood access for extracorporeal therapy in rabbits is described. The technique utilizes silicone rubber cannulae and teflon vessel tips to construct an externalized carotid-jugular arteriovenous shunt. The insertion procedure takes 1 h and extracorporeal blood flows in excess of 10 ml/min are obtainable for up to 7 days. Blood flow may still be obtained following shunt clotting by insertion of smaller diameter catheters through the arterial cannula. This technique has been successfully used for extracorporeal therapy in rabbit disease models.  相似文献   

3.
目的:研究微波热凝治疗变应性鼻炎的临床意义。方法:将6 3例变应性鼻炎随机分为两组,观察组31例施以微波凝固筛前神经鼻外侧支治疗,对照组32例施以抗组胺药物治疗。结果:两组近期和远期有效率分别是93.5 %、81.5 %和5 3.1%、4 5 .4 %。两组间疗效有显著差异(p <0 .0 1)。结论:微波热凝治疗变应性鼻炎是一种安全有效经济实用的方法,具有临床使用价值。  相似文献   

4.
ELISA for determination of allergen-specific IgG4 antibodies was developed with the help of monoclonal anti-IgG4 antibodies obtained by classic hybridoma technique. Subclass specificity of antibodies were studied in sera of 108 patients suffering from pollinosis. Antibodies of this isotype were found in the majority of patients with tree pollen allergy but not in patients with grass pollen allergy. The level of IgG4 antibodies correlated with the severity of the disease but not with the intensity of skin tests. Specific hyposensitization resulted in significant increase of IgG4 antibody level in patients with tree pollen allergy. Determination of IgG4 antibodies is proved to be useful to reveal tree pollen allergy and to monitor hyposensitization therapy.  相似文献   

5.
Rabbit liver microsomal cytochrome P-450 was immobilized by entrapment in calcium alginate gel. Aminopyrine demethylation experiments showed that the immobilized enzyme system is highly active and exhibits an unimpaired functional stability as compared with crude microsomes. The alginate entrapped microsomes were employed in a fixed bed recirculation reactor, where aminopyrine was continuously demethylated. Such model enzyme reactor can be a useful tool for studying extracorporeal drug detoxification or preparative substrate conversion with microsomal enzyme systems.  相似文献   

6.
Objective To determine the effectiveness of extracorporeal shock wave therapy compared with placebo in the treatment of chronic plantar fasciitis.Design Randomised, blinded, multicentre trial with parallel group design.Setting Nine hospitals and one outpatient clinic in Germany.Participants 272 patients with chronic plantar fasciitis recalcitrant to conservative therapy for at least six months: 135 patients were allocated extracorporeal shock wave therapy and 137 were allocated placebo.Main outcome measures Primary end point was the success rate 12 weeks after intervention based on the Roles and Maudsley score. Secondary end points encompassed subjective pain ratings and walking ability up to a year after the last intervention.Results The primary end point could be assessed in 94% (n=256) of patients. The success rate 12 weeks after intervention was 34% (n=43) in the extracorporeal shock wave therapy group and 30% (n=39) in the placebo group (95% confidence interval - 8.0% to 15.1%). No difference was found in the secondary end points. Few side effects were reported.Conclusions Extracorporeal shock wave therapy is ineffective in the treatment of chronic plantar fasciitis.  相似文献   

7.
Extracorporeal photochemotherapy is a new form of immunotherapy which involves the extracorporeal photoinactivation of peripheral blood cells by 8-methoxypsoralen in the presence of ultraviolet A irradiation, followed by readministration of the cells. To explore the efficacy of this therapy in the treatment of autoimmune disease, four patients with a lengthy history of corticosteroid and immunosuppressive drug-resistant pemphigus vulgaris were initiated on extracorporeal photochemotherapy. Three patients experienced a complete remission in cutaneous disease expression, permitting discontinuation of medications in two and a substantial decrease in the third. Significant reductions in serum antiepidermal cell antibody titers occurred in all four patients. The treatments were well tolerated without the occurrence of adverse events. These results in a small number of patients suggest that extracorporeal photochemotherapy may prove to be a useful tool in the treatment of aggressive autoimmune disease.  相似文献   

8.
In AIDS therapy, attempts have been made to inhibit the virus-encoded enzymes, e.g. HIV-1 protease, using active site-directed inhibitors. This approach is questionable, however, due to virus mutations and the high toxicity of the drugs. An alternative method to inhibit the dimeric HIV protease is the targeting of the interface region of the protease subunits in order to prevent subunit dimerization and enzyme activity. This approach should be less prone to inactivation by mutation. A list of improved 'dimerization inhibitors' of HIV-1 protease is presented. The main structural features are a short 'interface' peptide segment, including non-natural amino acids, and an aliphatic N-terminal blocking group. The high inhibitory power of some of the lipopeptides [e.g. palmitoyl-Tyr-Glu-Leu-OH, palmitoyl-Tyr-Glu-(L-thyronine)-OH, palmitoyl-Tyr-Glu-(L-biphenyl-alanine)-OH] with low nanomolar Ki values in the enzyme test suggests that mimetics with good bio-availability can be derived for AIDS therapy.  相似文献   

9.
Role of tumor necrosis factor in oxygen toxicity.   总被引:4,自引:0,他引:4  
mRNA from lungs of mice exposed to high-dose oxygen (greater than 95%) for 3 days demonstrated increased expression of the genes for tumor necrosis factor (TNF), interleukin-1, and interleukin-6 compared with mRNA from lungs of mice exposed to room air. Daily treatment of mice exposed to high-dose oxygen with an antibody to TNF improved survival compared with mice receiving a similar dose of control immunoglobulin G. Pretreatment of mice with repetitive sublethal intraperitoneal doses of recombinant human TNF for 3 days or a single intravenous dose followed by exposure to high-dose oxygen afforded a significant survival advantage compared with high-dose oxygen-exposed mice pretreated with vehicle or interleukin-1. The repetitive intraperitoneal TNF pretreatment reduced the development of interstitial pneumonitis, pulmonary edema, and lung weight gain associated with oxygen toxicity and enhanced expression of the gene for the free radical protective enzyme manganous superoxide dismutase in lung tissue, a gene that is augmented as mice are exposed to high-dose oxygen. Furthermore a single intravenous dose of TNF 24 h after oxygen exposure was still protective. The results suggest that the toxicity of oxygen therapy can be partially ameliorated by either treatment with anti-TNF antibody or pretreatment and early treatment with TNF. These findings are consistent with the hypothesis that oxygen exposure induces TNF, which causes part of the toxicity of high-dose oxygen, and that pretreatment or early treatment with TNF induces the gene for an enzyme that recently has been shown to be very effective in protecting mice from the toxicity of oxygen.  相似文献   

10.
l-asparaginase (l-asparagine amino hydrolase, E.C.3.5.1.1) is an enzyme clinically accepted as an antitumor agent to treat acute lymphoblastic leukemia and lymphosarcoma. It catalyzes l-asparagine (Asn) hydrolysis to l-aspartate and ammonia, and Asn effective depletion results in cytotoxicity to leukemic cells. Microbial l-asparaginase (ASNase) production has attracted considerable attention owing to its cost effectiveness and eco-friendliness. The focus of this review is to provide a thorough review on microbial ASNase production, with special emphasis to microbial producers, conditions of enzyme production, protein engineering, downstream processes, biochemical characteristics, enzyme stability, bioavailability, toxicity and allergy potential. Some issues are also highlighted that will have to be addressed to achieve better therapeutic results and less side effects of ASNase use in cancer treatment: (a) search for new sources of this enzyme to increase its availability as a drug; (b) production of new ASNases with improved pharmacodynamics, pharmacokinetics and toxicological profiles, and (c) improvement of ASNase production by recombinant microorganisms. In this regard, rational protein engineering, directed mutagenesis, metabolic flux analysis and optimization of purification protocols are expected to play a paramount role in the near future.  相似文献   

11.
12.
The aim of this report was to answer the question how specific immunotherapy influences the antioxidant enzyme system in patients with respiratory allergy and in longer perspective to find markers suitable to assess the efficacy of treatment. In open prospective randomised study 28 patients (18 females and 10 males, age 14–48 years) with seasonal respiratory allergy were treated with allergen immunotherapy. Subjects received subcutaneous therapy with allergens absorbed on calcium phosphate or aluminium hydroxide and were analyzed by the established protocol at the beginning, after three and 12 month of the treatment. In all treatment group red cell superoxide dismutase and glutathione peroxidase activities were in the normal range in allergic patients both before and during the treatment. Catalase activity in the allergic patients was lower as compared with controls and a significant increase of the enzyme activity occurred during and at the end of the treatment. In patients treated with calcium phosphate adsorbed allergen there was a continous increase of catalase activity from beginning up to the end of observation. In the case of the aluminium hydroxide treatment there was an increase from the baseline values up in the third month of the treatment and a decrease on the 12th month. In summary, the present results open the question that allergen immunotherapy may cause imbalance of oxidants and antioxidants. To support our findings larger controlled field studies are needed.  相似文献   

13.
14.
There is increasing documentation of allergic contact dermatitis and other effects from gold jewelry, gold dental restorations, and gold implants. These effects were especially pronounced among females wearing body-piercing gold objects. One estimate of the prevalence of gold allergy worldwide is 13%, as judged by patch tests with monovalent organogold salts. Eczema of the head and neck was the most common response of individuals hypersensitive to gold, and sensitivity can last for at least several years. Ingestion of beverages containing flake gold can result in allergic-type reactions similar to those seen in gold-allergic individuals exposed to gold through dermal contact and other routes. Studies with small laboratory mammals and injected doses of colloidal gold showed increased body temperatures, accumulations in reticular cells, and dose enhancement in tumor therapy; gold implants were associated with tissue injuries. It is proposed that Au degrees toxicity to mammals is associated, in part, with formation of the more reactive Au+ and Au3+ species.  相似文献   

15.

Background

Food allergy has been reported increasingly around the world during the past several decades. Epstein-Barr virus (EBV), a common herpesvirus with high infection rate, is now suspected to be a risk or protective factor in food allergy. The aim of the study was to investigate the possible role of EBV infection in IgE-mediated food allergy.

Methods

34 patients with an egg allergy and 34 healthy controls participated in this study. Egg allergy was confirmed by open-food challenge. Serum anti-viral capsid antigen (VCA), anti-Epstein-Barr nuclear antigen 1 (EBNA-1) IgG and egg specific (yolk and white)-IgE levels were evaluated by enzyme linked immunosorbent assay (ELISA). At the same time, EBV DNA as well as viral miRNAs in these samples was quantified by real-time PCR.

Results

The results showed that serum anti EBNA-1 IgG and two viral miRNAs (miR-BART1-5p and miR-BART7) were highly expressed in patients with egg allergy compared with healthy controls (p < 0.05, < 0.001 and < 0.01, respectively). Moreover, the expressions of anti EBNA-1 specific IgG, miR-BART1-5p and miR-BART7 positively correlated with the level of egg-specific IgE (p < 0.05, < 0.01 and < 0.01, respectively). The differences in anti VCA IgG concentration and EBV DNA copy number between the allergy patients and control individuals were not statistically significant.

Conclusions

The high expression of EBV-specific antibody and miRNAs indicated that EBV infection might play a promoting role in IgE-mediated egg food allergy, and viral miRNAs-related immunomodulatory pathway was likely involved in this allergy process.  相似文献   

16.
ABSTRACT: INTRODUCTION: Insulin allergy to human insulin preparations during the treatment of diabetes is suggested to occur at rates ranging from <1.0% to 2.4%. These reactions vary from mild localized reactions, which resolve with repeated exposure, to life-threatening anaphylaxis and death. The management of persistent insulin allergy in type 1 diabetes mellitus is particularly complicated because ongoing treatment with insulin is essential. CASE PRESENTATION: We present the case of a 12-year-old Caucasian girl with localized allergy to the insulin excipient metacresol, and the subsequent desensitization therapy using continuous subcutaneous insulin infusion with simultaneous intravenous insulin infusion. CONCLUSIONS: This is the first documented case of allergy to the metacresol component of insulin in the pediatric type 1 diabetes literature. We describe an approach to diagnosis and management of metacresol allergy in type 1 diabetes.  相似文献   

17.
One hundred and thirty-two patients known or suspected of allergy to house dust were skin-tested with pure extracts of four varieties of dust mites. The results show that both Dermatophagoides culinae and D. pteronyssinus probably played important parts in sensitizing susceptible people, as did Glycyphagus destructor and G. domesticus in some cases. In some patients these results enabled successful desensitization against the dust to be carried out, and for corticosteroid therapy to be stopped. Hence the use of mite extracts is considered to be an important advance in the diagnosis of allergy to house dust.  相似文献   

18.
Lipopolysaccharides (LPS) play a key role in the pathogenesis of septic shock, a major cause of mortality in the critically ill patient. The only therapeutic option aimed at limiting downstream systemic inflammatory processes by targeting lipopolysaccharide is Toraymyxin, an extracorporeal hemoperfusion device using solid phase-immobilized polymyxin B (PMB). While PMB is known to effectively sequester LPS, its severe systemic toxicity proscribes its parenteral use, and hemoperfusion may not be feasible in patients in shock. In our continuing efforts to develop small-molecule mimics which display the LPS-sequestering properties, but not the toxicity of PMB, a series of mono- and bis-substituted dialkylpolyamines were synthesized and evaluated. We show that EVK-203, an alkylpolyamine compound, specifically binds to and neutralizes the activity of LPS, and affords complete protection in a murine model of endotoxic shock. EVK-203 is without any apparent toxicity when administered to mice at multiples of therapeutic doses for several days. The specific endotoxin-sequestering property along with a very favorable therapeutic index renders this compound an ideal candidate for preclinical development.  相似文献   

19.
Food products and allergy development, prevention and treatment   总被引:1,自引:0,他引:1  
In westernized countries allergic diseases have reached epidemic proportions. Food is frequently a perpetrator of allergy but, in turn, modified food and selected food ingredients can become valuable intervention tools in the fight against allergy. There are two basic approaches towards mitigation of food allergy through nutrition: to reduce the allergenicity of raw food materials by physical, chemical or genetic methods or to influence host immunity towards a non-allergic state using various food ingredients. Dietary intervention for the prevention and therapy of allergy is an emerging field where initial findings from animal studies are now being validated in human trials. Nevertheless, to consolidate the utility of such interventions, more pre-clinical and clinical studies remain necessary.  相似文献   

20.
Because of an increasing incidence of poisoning with the newer organophosphorus anticholinesterase insecticides, these compounds have been reviewed in terms of their history and pharmacology, relationship with other drugs, factors affecting toxicity, mechanism of action, toxic signs and treatment. The modern organophosphorus pesticide requires metabolic conversion before toxicity develops. Insects have a greater propensity for this conversion than humans. Nevertheless, this conversion does occur in humans and can be potentiated by other drugs. Toxicity also varies with age, sex, route and frequency of administration, and previous exposure. The mechanism of toxicity is inhibition of acetylcholinesterase, causing an intoxicating build-up of acetylcholine. Signs and symptoms consist of the clinical manifestations of unopposed parasympathetic and central activity. Treatment must be initiated early. Respiration must be maintained and the effects of acetylcholine must be counteracted by massive doses of atropine. Metaraminol enhances the antagonistic action of atropine against acetylcholine and may also be given. Once acetylcholinesterase is inactivated, restoration is slow. Recovery can be accelerated by enzyme reactivators like the oxime compounds. Pyridine aldoxime (Pralidoxime, Protopam, P2S and 2-PAM) can be given in combination with atropine and metaraminol (AMP therapy) and may be the treatment of choice.  相似文献   

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