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1.
OBJECTIVE: To assess inhalation technique in patients after written instruction alone, written and verbal instruction, and clinical use of two new inhalation devices. DESIGN: Randomized, crossover evaluation of the albuterol Diskhaler and the terbutaline Turbuhaler. SETTING: Canadian tertiary-care hospital. PATIENTS: Twenty hospitalized adults with asthma or chronic obstructive pulmonary disease currently using an albuterol metered-dose inhaler (MDI). Nineteen patients received Diskhaler, 16 received Turbuhaler, 15 received both inhalers, and 10 patients used both inhalers for three days each. INTERVENTIONS: Patients were randomized to receive either Diskhaler or Turbuhaler for three days. Inhaler technique was assessed after written instruction, written plus verbal instruction, at the first scheduled dose after instruction, and after three days of clinical use. Patients remaining in the hospital after three days crossed over to the other study inhaler and the same protocol was followed. MAIN OUTCOME MEASURES: Patient inhalation technique was assessed and compared for the MDI, Diskhaler, and Turbuhaler. RESULTS: Assessment of MDI technique revealed that 35 percent of patients used their MDI correctly on the first puff, and 42 percent used it correctly on the second puff. Following written instruction alone, correct technique was demonstrated by 32 percent of patients with Diskhaler and 6 percent with Turbuhaler. Technique significantly improved following verbal instruction, although 40 percent of the patients required up to three attempts to demonstrate correct technique on at least one of the study inhalers. After three days of clinical use, correct technique was demonstrated in only 54 percent of the Diskhaler and 64 percent of the Turbuhaler assessments. Performance at this assessment was, however, significantly better on the Turbuhaler than on the MDI (p = 0.01). Performance on the Diskhaler was not significantly different from the performance on the other inhalers. CONCLUSIONS: Written instruction alone is inadequate in teaching correct inhalation technique. Verbal instruction and technique assessment are essential for patients to achieve proper technique. Patients may perform better on the Turbuhaler than on other inhalation devices.  相似文献   

2.
Patients attending the emergency room with acute asthma, participating in a study comparing salbutamol (albuterol in the United States) via a dry powder inhaler (Turbuhaler) with pressurized metered-dose inhaler (pMDI), were included in this 1-week follow-up study with the aim of assessing whether inhaled budesonide via Turbuhaler may be an alternative to prednisolone tablets after an acute asthma attack. Eighty-one patients with a mean age of 38 years and forced expiratory volume in 1 sec (FEV1) of 64% predicted normal value after treatment with salbutamol were randomized in this double-blind, double-dummy, parallel-group study. The doses given were budesonide 1600 microg b.i.d. or prednisolone in daily doses from 40 mg (day 1) decreased to 5 mg (day 7). FEV1 was recorded before and after the 7-day treatments and peak expiratory flow (PEF) morning and evening, clinical symptoms (visual analogue scale 0-100), and doses of rescue medication (terbutaline Turbuhaler 0.25 mg/dose) were recorded daily. The mean increase in FEV1 from baseline to day 7 was 17.3% in the budesonide Turbuhaler group and 17.6% in the prednisolone group. Mean values of morning PEF increased from day 1 to day 7 by 67 L/min in the budesonide Turbuhaler group and by 57 L/min in the prednisolone group (not significant). There were no statistically significant differences between the groups in clinical symptoms and in the number of doses of rescue medication. Because of disease deterioration, five patients in the Turbuhaler group and three in the prednisolone group needed additional symptomatic as well as corticosteroid treatment. Inhaled budesonide in high doses may be a substitute for oral therapy as follow-up treatment after an acute asthma attack.  相似文献   

3.
The bronchodilating effect of terbutaline dry powder inhaled via Turbuhaler was compared with terbutaline inhaled via a conventional, chlorofluorocarbon (CFC) inhaler and Nebuhaler (750 ml spacer) in 68 consecutive patients attending the emergency department with acute severe bronchial obstruction. The study was of an open, randomized, parallel group design with one study day. Patients were treated with 2.5 mg of terbutaline 15 min apart, either as dry powder via Turbuhaler or with a CFC inhaler in conjunction with Nebuhaler. Data from 62 patients were analyzed. The mean baseline FEV1 values were 0.81 L (SD, 0.64; range, 0.14 to 2.74 L) in the Turbuhaler group (n = 33), and 0.90 L (SD, 0.90; range, 0.27 to 2.60 L) in the Nebuhaler group (n = 29). The mean increases in FEV1 from baseline were 0.40 L (SD, 0.40; range, 0.06 to 2.36 L) and 0.21 L (SD, 0.25; range, -0.05 to 0.95 L) 10 min after the last inhalation via Turbuhaler and Nebuhaler, respectively. The difference between mean values of the increase in FEV1 after terbutaline treatment with Turbuhaler and the CFC inhaler and Nebuhaler was statistically significant (p = 0.0004, ANOVA). This study showed that inhalation of terbutaline via Turbuhaler produced a significantly greater increase in FEV1 compared with the same dose of terbutaline administered via the CFC inhaler and Nebuhaler in patients attending the emergency department with acute severe bronchial obstruction.  相似文献   

4.
This randomized, double-blind, crossover study in two parts compared tolerability to high doses of formoterol (Oxis Turbuhaler) with that of high doses of terbutaline (Bricanyl Turbuhaler). After Holter monitoring at home, 12 patients were treated with 4+4+4 doses of formoterol Turbuhaler, 6 microg x dose(-1), (total daily metered dose 72 microg) or 4+4+4 doses of terbutaline Turbuhaler, 0.5 mg x dose(-1) (daily dose 6 mg) given in the morning, after lunch and in the evening, for 3 consecutive days. After a one week washout period at home, patients received the alternative treatment. Thereafter, 15 other patients received 8+6+6 doses of formoterol Turbuhaler (total daily metered dose 120 microg) or 8+6+6 doses of terbutaline Turbuhaler (daily dose 10 mg). Pulse, cardiac frequency, blood pressure, serum potassium, electrocardiogram and forced expiratory volume in one second (FEV1) were registered at regular intervals and Holter monitoring was applied during all 4 treatment days. Terbutaline 6 mg showed significantly greater systemic effects than formoterol 72 microg on pulse, blood pressure, cardiac frequency and QTc (QT interval corrected for heart rate). Terbutaline 10 mg had significantly greater effects than formoterol 120 microg on serum potassium levels, pulse, cardiac frequency and QTc. No differences in FEV1 levels were found. Both drugs were safe and generally well tolerated on both dose levels. In conclusion, high doses of formoterol Turbuhaler over 3 days were generally safe and well tolerated. Daily doses of 6 mg and 10 mg terbutaline Turbuhaler were systemically more potent than 72 microg and 120 microg formoterol, respectively. The safety margin thus appears to be wide if patients happen to use extra doses of formoterol in addition to those prescribed for regular use.  相似文献   

5.
Salmeterol and formoterol are two long-acting beta2-agonists for inhalation, currently being used in clinical practice. The aim of the present study was to investigate the onset of action, duration of effect and potency of these two beta2-agonists in asthmatic patients. Patients (n=28) were included on the basis of salbutamol stepwise reversibility (100, 100 and 200 microg, given cumulatively; total reversibility > or =15%). In a double-blind placebo-controlled crossover study, the bronchodilating properties of formoterol 6, 12 and 24 microg were compared with the effects of salmeterol 50 microg. Formoterol was given via Turbuhaler and salmeterol via Diskhaler, and forced expiratory volume in one second (FEV1) was monitored during 12 h. Formoterol at all doses had a more rapid onset than salmeterol as judged from bronchodilation at 3 min after the dose. Formoterol at all doses had a similar duration of effect to salmeterol 50 microg, as judged from bronchodilation at 12 h after dose administration. When the relative potency of the two drugs was compared, salmeterol 50 microg was estimated to correspond to formoterol 9 microg (95% confidence interval: 3-19 microg). We confirm that formoterol and salmeterol are both long-acting beta2-agonists, but with some differences in effect profile. We confirm the more rapid onset of action of formoterol compared with salmeterol, and furthermore, no difference in duration of effect is evident.  相似文献   

6.
Local administration of drugs by means of aerosol device is widely used in the treatment of asthma. Nevertheless, the effectiveness of this method depends on an adequate inhalation technique (IT), which available evidence has shown to be rather problematic. The aim of this study was to assess IT in out-patients with bronchial asthma who frequently use aerosol therapy with Pressurized Metered dose inhalers (MDI), pressurized inhalers with spacer (MDI-S) and the Astra-Draco Turbuhaler system (TH). A sample of 150 adults with asthma were evaluated. These patients had been followed up for than two years and they often used one of the devices mentioned above. The IT has broken down into several steps for each procedure. Percentages of patients with one error in the IT were 50%, 44% and 42% for MDI, MDI-S and TH procedures, respectively. 18%, 20% and 14% of patients committed three errors in the IT, respectively. Differences detected were not significant. Seven patients committed errors in every step of the IT. In conclusion, the level of errors found in our study is high, similar to that cited in the existing literature. It is also roughly equivalent for the three devices tested. We believe that the proper teaching monitoring of IT skills is highly important in the treatment of bronchial asthma.  相似文献   

7.
Local side-effects, such as hoarseness and oropharyngeal candidiasis, are often seen during treatment of patients with inhaled corticosteroids (ICS). We investigated whether changing from pressurized metered-dose inhalers (pMDI) to Turbuhaler influenced the type and frequency of local side-effects. Local side-effects were recorded for a 2-year period in which 154 patients used ICS pMDI with a spacer device. They were followed for an equally long period of time (26.2 +/- 5.7 months) while using Turbuhaler, as were 90 patients who received Turbuhaler as their first ICS preparation. After inhalation, all patients rinsed out their mouths with water. In experienced pMDI-users, the frequency of local side-effects decreased from 21% to 6%. The reduction was due to a lower incidence of hoarseness. Candidiasis or hoarseness was not seen in patients given Turbuhaler as their first ICS device. Our fear of an increased incidence of local side-effects when giving ICS in Turbuhaler was unwarranted.  相似文献   

8.
The aim of the present study was to examine the efficacy of low-dose inhaled budesonide (BUD) administered via Turbuhaler once or twice daily on symptoms, lung function and bronchial hyperreactivity in children with mild asthma. One hundred and sixty-three children (mean age 9.9 yrs, 56 females/107 males) with mild asthma (forced expiratory volume in one second (FEV1) 103% of predicted, morning peak expiratory flow (PEF) 87% pred, reversibility in FEV1 3%, fall in FEV1 after exercise 10.4% from pre-exercise value) and not previously treated with inhaled steroids, were included in a double-blind, randomized, parallel-group study. After a two-week run-in period, the children received inhaled BUD 100 microg or 200 microg once daily in the morning, 100 microg twice daily or placebo for 12 weeks. Exercise and methacholine challenges were performed before and at the end of treatment. After 12 weeks of therapy, the fall in FEV1 after an exercise test was significantly less in all three BUD groups (43-5.1%) than in the placebo group (8.6%). Bronchial hyperreactivity to methacholine with the provocative dose causing a 20% fall in FEV1 decreased significantly in the BUD 100 microg twice-daily group compared with placebo (ratio at the end of treatment 156%). Changes in baseline lung function (FEV1 and PEF) were less marked than changes in bronchial responsiveness. In conclusion, low doses of inhaled budesonide, given once or twice daily, provided protection against exercise-induced bronchoconstriction in children with mild asthma and near normal lung function.  相似文献   

9.
BACKGROUND: The role of long-acting, inhaled beta2-agonists in treating asthma is uncertain. In a double-blind study, we evaluated the effects of adding inhaled formoterol to both lower and higher doses of the inhaled glucocorticoid budesonide. METHODS: After a four-week run-in period of treatment with budesonide (800 microg twice daily), 852 patients being treated with glucocorticoids were randomly assigned to one of four treatments given twice daily by means of a dry-powder inhaler (Turbuhaler): 100 microg of budesonide plus placebo, 100 microg of budesonide plus 12 microg of formoterol, 400 microg of budesonide plus placebo, or 400 microg of budesonide plus 12 microg of formoterol. Terbutaline was permitted as needed. Treatment continued for one year; we compared the frequency of exacerbations of asthma, symptoms, and lung function in the four groups. A severe exacerbation was defined by the need for oral glucocorticoids or a decrease in the peak flow to more than 30 percent below the base-line value on two consecutive days. RESULTS: The rates of severe and mild exacerbations were reduced by 26 percent and 40 percent, respectively, when formoterol was added to the lower dose of budesonide. The higher dose of budesonide alone reduced the rates of severe and mild exacerbations by 49 percent and 37 percent, respectively. Patients treated with formoterol and the higher dose of budesonide had the greatest reductions -- 63 percent and 62 percent, respectively. Symptoms of asthma and lung function improved with both formoterol and the higher dose of budesonide, but the improvements with formoterol were greater. CONCLUSIONS: In patients who have persistent symptoms of asthma despite treatment with inhaled glucocorticoids, the addition of formoterol to budesonide therapy or the use of a higher dose of budesonide may be beneficial. The addition of formoterol to budesonide therapy improves symptoms and lung function without lessening the control of asthma.  相似文献   

10.
Aerosol therapy     
Aerosol therapy plays a major role in the diagnosis and treatment of various lung diseases. The aim of inhalation therapy is to deposit a reproducible and adequate dose of a specific drug to the airways, in order to achieve a high, local, clinical effect while avoiding serious systemic side effects. To achieve this goal, it is therefore important to have an efficient inhalation device to deliver different medications. However, the currently available therapeutic inhalation devices (nebuliser, pressurised metered-dose inhaler and dry powder inhaler) are not very efficient in aerosol delivery and have several disadvantages. Inhalation devices can be assessed by in vitro studies, filter studies and radiolabelled deposition studies. Several radiolabelled deposition studies have shown that nebulisers and pressurised metered-dose inhalers are not very efficient in aerosol delivery. In children, before 1997, only 0.5% to 15% of the total nebulised or actuated dose from a nebuliser or pressurised metered-dose inhaler actually reached the lungs. These numbers were somewhat improved in adults, 30% of the total nebulised or actuated dose reaching the airways. Aerosol therapy with dry powder inhalers was the most efficient before 1997, 30% of the total dose being deposited in the lungs of adults and children. In 1997, new developments in pressurised metered-dose inhalers much improved their efficiency in aerosol delivery. Lung deposition can be increased by up to 60% with use of a non-electrostatic holding chamber and/or a pressurised metered-dose inhaler with a hydrofluoroalkane propellant possessing superior aerosol characteristics. Several studies comparing the clinical efficiency of different inhalation devices have shown that the choice of an optimal inhalation device is crucial. In addition to the aerosol characteristics, ventilation parameters and airway morphology have an important bearing on deposition patterns. These parameters may be greatly influenced by the patient's acceptance of a specific inhalation device and therefore determine the choice of the device used. It is important for the clinical impact to develop more efficient inhalation devices, which need to be assessed for use in different age groups. These devices should be cheap, easy to use, portable, usable with all medications and environmentally safe.  相似文献   

11.
PURPOSE: The bronchodilator effect of salbutamol formulated in hydrofluoroalkane-134a (HFA-134a), a chlorofluorocarbon (CFC)-free propellant for metered dose inhalation (MDI) devices, was compared with that of salbutamol formulated in CFC in anesthetized dogs. METHODS: Bronchospasms were induced by the intravenous injection of histamine, and bronchial resistance was measured by the method of Konzett and Rossler. RESULTS: While the placebo vehicles (HFA-134a and CFC propellants) had no significant effect on histamine-induced bronchospasms, the salbutamol/HFA-134a and salbutamol/CFC MDI formulations had equivalent dose-related inhibitory effects. CONCLUSIONS: These data indicated that salbutamol formulated in HFA-134a and that in CFC propellant are bioequivalent.  相似文献   

12.
Quinolone antibacterial drugs inhibit DNA gyrase, a type 2 topoisomerase. Since topoisomerases are present in eukaryotic cells, it was of interest to evaluate the antifungal activities of two clinically available quinolones, ciprofloxacin and trovafloxacin, alone and in combination with amphotericin B or fluconazole, in vitro against Candida albicans and in a murine model of invasive candidiasis. The in vitro activity of trovafloxacin was also tested against other yeasts and molds. In vitro, trovafloxacin exhibited no antifungal activity against any of the fungi (MIC, >250 microg/ml). There was also no effect of the quinolone on the in vitro activity of either antifungal drug. Marked antifungal effects were seen, however, in the murine model of candidiasis. In all experiments, control mice infected intravenously with C. albicans were dead by day 24. While either quinolone had minimal effects on survival of mice when used alone in oral doses of up to 40 mg/kg twice daily, the combination of the quinolone with fluconazole (40 or 80 mg/kg given twice daily by oral gavage) was more effective in prolonging survival than was fluconazole alone. Colony counts of kidneys on days 12 and 30 showed similar reductions in C. albicans recovered from mice treated with fluconazole with or without trovafloxacin or amphotericin B with or without trovafloxacin. Survival of mice treated with a suboptimal dose of amphotericin B (0.2 mg/kg/day) was also improved when trovafloxacin (40 mg/kg) given twice daily was included (0 versus 27%, respectively; P < 0.05). While the mechanisms of action of the combination of trovafloxacin and amphotericin B or fluconazole are unclear, further work focused on fungal topoisomerase inhibition and the mechanism of the antifungal effect of quinolone antibacterial drugs is warranted.  相似文献   

13.
The distribution pattern of budesonide in the nasal passages and lungs was investigated in 10 healthy subjects after nasal inhalation. The subjects inhaled drug powder, radiolabelled with 99mTc, at maximum flow rate (46.3 +/- 6.8 l/min) and at 29.9 +/- 2.5 l/min via Turbuhaler. At both flows, the majority of the dose was deposited in the anterior part of the nasal cavity on a single, rather localized area, but some particles also penetrated more posteriorly into the main nasal passages and to the lungs. At maximum flow rate the nasal deposition was 65.2% (range 39.5-84.1%) and the lung deposition 4.7% (range 1.4-9.3%) of the metered dose, and at 30 l/min, the nasal deposition was 67.6% (range 49.7-81.6%) and the lung deposition was 4.2% (range 1.7-7.9%). A large fraction of the metered dose was deposited in the nasal adaptor of the inhaler during the administration (mean values 29 and 28%, for the two inhalation flows). Of the dose actually reaching the subject, 91 and 93% (mean values) was deposited in the nose. There were no statistically significant differences in distribution pattern between the two inhalation flows.  相似文献   

14.
BACKGROUND: Nonspecific bronchial provocation tests may be simplified by the use of hand-held devices to deliver methacholine. OBJECTIVE: To study the feasibility of using a metered-dose inhaler (MDI) to administer methacholine in bronchial provocation tests, and the ability of such a device to diagnose bronchial hyperresponsiveness (BHR) accurately. METHODS: In an open randomized crossover pilot study, we compared the provocative dose that induces a 20% fall in FEV1 (PD20 FEV1) obtained with the methacholine MDI with that obtained using a conventional nebulizer in 20 hyperresponsive and 20 nonhyperresponsive subjects. The MDI delivers 400 doses of 100 microg of methacholine, and was used via a spacer. Bronchial hyperresponsiveness (BHR) was defined as a PD20 FEV1 <2,000 microg with the conventional test using the nebulizer. The tests were performed in each subject in a randomized order, 1 to 7 days apart. RESULTS: Of the subjects who had a nebulizer PD20 FEV1 <2,000 microg, all but one had an MDI PD20 FEV1 <800 microg. When 800 microg was taken as the threshold for the diagnosis of BHR with the MDI test, the accuracy of this test to diagnose BHR was 97.5%, and the two tests were highly concordant for the diagnosis of BHR (Pearson chi2, 36.19; p<0.0001). CONCLUSION: A hand-held device may be suitable for delivery of methacholine during bronchial provocation tests, if these results are confirmed in large samples.  相似文献   

15.
Twelve healthy male volunteers participated in this open, randomized, placebo-controlled, two-way crossover study to investigate the effects of cimetidine on the steady-state pharmacokinetics of oral trovafloxacin. Volunteers were randomized to receive either 400 mg cimetidine twice daily or placebo for 5 days. From day 3-5, volunteers received 200 mg trovafloxacin once daily in addition to either cimetidine or placebo. After a minimum 7-day washout period, the study was repeated: those volunteers who received placebo during the first study period were administered cimetidine, and vice versa. The maximum observed serum trovafloxacin concentration, the area under the concentration-time curve of trovafloxacin within the dosing interval of 24 h and the earliest time to the maximum serum concentration for trovafloxacin in volunteers receiving concomitant cimetidine were 2.4 microg/ml. 27.8 microg x h/ml and 1.4 h, respectively, compared with 2.5 microg/ml, 27.1 microg x h/ml and 1.5 h, respectively, in volunteers receiving concomitant placebo. Thus. multiple dosing with cimetidine had no significant effect on the absorption or disposition of trovafloxacin at steady state. Co-administration of cimetidine and trovafloxacin was also well tolerated and without serious adverse effects.  相似文献   

16.
Hair cells in the basilar papilla of birds have the capacity to regenerate after injury. Methods commonly used to induce cochlear damage are systemic application of ototoxic substances such as aminoglycoside antibiotics or loud sound. Both methods have disadvantages. The systemic application of antibiotics results in damage restricted to the basal 50% of the papilla and has severe side effects on the kidneys. Loud sound damages only small parts of the papilla and is restricted to the short hair cells. The present study was undertaken to determine the effect of local aminoglycoside application on the physiology and morphology of the avian basilar papilla. Collagen sponges loaded with gentamicin were placed at the round window of the cochlea in adult pigeons. The time course of hearing thresholds was determined from auditory brain stem responses elicited with pure tone bursts within a frequency range of 0.35-5.565 kHz. The condition of the basilar papilla was determined from scanning electron micrographs. Five days after application of the collagen sponges loaded with gentamicin severe hearing loss, except for the lowest frequency tested, was observed. Only at the apical 20% of the basilar papilla hair cells were left intact, all other hair cells were missing or damaged. At all frequencies there was little functional recovery until day 13 after implantation. At frequencies above 1 kHz functional recovery occurred at a rate of up to 4 dB/day until day 21, beyond that day recovery continued at a rate below 1 dB/day until day 48 at the 5.6 kHz. Below 1 kHz recovery occurred up to day 22, the recovery rate was below 2 dB/day. A residual hearing loss of about 15-25 dB remained at all frequencies, except for the lowest frequency tested. At day 20 new hair cells were seen on the basilar papilla. At day 48 the hair cells appeared to have recovered fully, except for the orientation of the hair cell bundles. The advantage of the local application of the aminoglycoside drug over systemic application is that it damages almost all hair cells in the basilar papilla and it has no toxic side effects. The damage is more extensive than with systemic application.  相似文献   

17.
OBJECTIVES: To study pravastatin and lovastatin pharmacokinetic and pharmacodynamic effects and their interactions with cydosporine (INN, ciclosporin) in kidney transplant patients after single and multiple doses. SUBJECTS AND METHODS: The pharmacokinetic and pharmacodynamic effects of administration of 20 mg/day oral pravastatin and lovastatin for 28 days and their interactions with cyclosporine (2 to 6 mg/kg/day) were studied in a double-blind, double-dummy, randomized, parallel-group multicenter trial in 44 stable kidney graft recipients. RESULTS: The median area under the curve [AUC(0-24)] of pravastatin was 249 microg x hr/L (range, 104 to 1026 microg x hr/L) after a single dose (day 1) and 241 microg x hr/L (114 to 969 microg x hr/L) after multiple doses (day 28) and was fivefold higher than values reported in the absence of cyclosporine. The median AUC(0-24) of lovastatin was 243 microg x hr/L (105 to 858 microg x hr/L) on day 1 and 459 microg x hr/L (140 to 1508 microg x hr/L) on day 28. Besides a significant accumulation during the study period (p < 0.001), the lovastatin AUC(0-24) values were twentyfold higher than values reported without cyclosporine. Coadministration of pravastatin or lovastatin did not alter cyclosporine pharmacokinetics. In this study, 20 mg/day doses of both drugs resulted in a significant improvement of the lipid profile and were well tolerated. CONCLUSIONS: In contrast to lovastatin, pravastatin did not accumulate over the study period, which is probably one of the reasons rhabdomyolysis has been reported in lovastatin-treated but not pravastatin-treated transplant patients receiving cyclosporine immunosuppression.  相似文献   

18.
Specific protein phosphatase activity against protein kinase C-phosphorylated substrate was measured in the rat ovary during pseudopregnancy and pregnancy. Tissues were processed in the presence of sodium fluoride and inorganic phosphate to inhibit the phosphatase and thereby prevent autodephosphorylation of the type 2A protein phosphatase (PP2A) during homogenization. Manganese was added at the time of enzyme assay to reactivate the phosphatase. The specific activity of the protein phosphatase did not vary significantly across pseudopregnancy (p > 0.05). In contrast, the specific activity of protein phosphatase decreased significantly between Day 7 and Day 10 of pregnancy (28.8 +/- 5 pmol/min x microg protein and 20.7 +/- 2 pmol/min x microg protein, respectively; p < 0.05) and remained at the decreased value for the remainder of pregnancy. To determine whether hormones of pregnancy could regulate PP2A activity in the ovaries, pseudopregnant rats were treated with prolactin (3 IU twice a day), bromocriptine (100 microg twice a day), or estradiol benzoate (50 microg). Bromocriptine and estradiol treatments caused a decrease in PP2A-specific activity, but prolactin had no effect. Bromocriptine treatment caused a decrease in the protein content of the PP2A catalytic subunit, but prolactin and estradiol treatments had no effect. The data suggest that the specific activity and protein content of PP2A in the rat ovary are hormonally regulated.  相似文献   

19.
Streptococcus pneumoniae strains have emerged that are resistant to penicillin (MICs >0.06 microg/mL) and many other beta-lactams. However, some older compounds such as amoxicillin have potency against these pneumococci with altered penicillin-binding proteins, but are labile to beta-lactamases produced by other prevalent respiratory tract pathogens. The interactions of amoxicillin with an enzyme-stable cephalosporin (cefixime) with a long elimination half-life were examined by the checkerboard dilution method versus 39 S. pneumoniae strains (13 resistant, 15 intermediate, and 11 susceptible to penicillin). Among 24 strains with evaluable drug interaction tests, 17 (71%) demonstrated partial or complete synergy. This favorable interaction produces a cefixime susceptibility category change from resistant or intermediate to susceptible for 16 of 28 strains (57%), when combined with < or = 1 microg/mL amoxicillin. Thus, the use of two currently available oral beta-lactams (amoxicillin twice a day + cefixime once a day; three total doses) appears to be a potential alternative treatment with greater spectrum for community-acquired respiratory tract infections pending clinical trial results.  相似文献   

20.
In connection with a study on the prophylaxis of infectious diarrhea with specific egg yolk antibodies, the systemic availability of colostral bovine immunoglobulin G (bIgG) and chicken immunoglobulin Y (IgY) after feeding egg powder was investigated on 26 newborn calves from 23 different farms. Blood was sampled daily and at the same day time from these calves in the first 14 days of life. During the feeding of colostrum, the mean bIgG concentration was highest at day 1 post natum with a value of 9.3 mg/ml serum. Thereafter, the mean bIgG level was reduced continuously to a significant lower concentration of 4.9 mg/ml serum at day 12 post natum and remained nearly constant at 5.2 mg/ml till to the end of the observation period. Total protein concentrations in the serum did not change and plateaued at a mean value of 56.2 mg/ml (SD 11.2). The number of colostrum meals had no significant effect on the mean bIgG concentrations during that period. The individual variation of bIgG concentrations was very high on every day of the sampling period. The mean coefficient of variation was at 52.1 % (SD 5.7). After having described the individual bIgG concentration curves mathematically with a regression curve, two groups with significantly different bIgG elimination constants (k) could be obtained. Thus in one group (n = 10) with k-values of < -0.02 a mean half time of serum bIgG of 24.3 days (SD 4.6) was calculated. In the other group of calves (n = 16) with elimination constants of k > -0.02, a mean half time of 68.5 days (SD 36.7) could be calculated, possibly because these calves started earlier with their endogenous bIgG production. Additionally, to 18 of these calves 20 g egg powder with an IgY concentration of 15 mg/g was fed up to day 14. Calves had a maximal mean IgY concentration of 1.9 micrograms/ml serum if egg powder feeding started already during the first 12 hours of life. Starting at a later time resulted in a significant reduction of IgY levels. For example, the mean initial IgY concentration dropped to 0.035 micrograms/ml serum after having had the first egg powder application between 25 and 48 hours post natum. Using the individual IgY elimination constant derived from a regression analysis (r2 = 0.84) of the IgY concentration curve, a mean IgY half time of 5.0 days (SD 2.5) could be calculated. To prevent the absorption of heterologous antibodies and consecutively, also to prevent a possible systemic effect, egg powder for prophylactic purposes in newborn calves should be fed after the first 24, better 48 hour, post natum. Most important for the prophylactic effect of specific antibodies on infectious diarrhea is not their systemic but their high local intestinal availability.  相似文献   

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