Study of the process of secondary failure of sulphonylurea by a Markov model.

PURPOSE: The study was to reflect and forecast the evolutive tendency and influence factors of secondary failure of sulphonylurea (SFS) changing with time by using a Markov (MKV) model in the elderly diabetic population in Shanghai. METHODS: A total of 549 patients with elderly diabetes mellitus (DM) were enrolled and grouped in the study. A door-to-door retrospective epidemiological survey was used to collect data. The MKV model was used to assess the process and influence factors of SFS and the MKV process decision support system was adopted to calculate state probability of the MKV process. RESULTS: The rate of SFS in the group of all cases, FPG < or = 10 mmol . L(-1) before treatment and FPG > 10 mmol . L(-1) before treatment, taking single type of sulphonylurea (SU) and taking two types of SU and over respectively was 9.11%, 3.55%, 11.03%, 8.54% and 11.21%. The years of changing into the state of secondary failure in half patients was 5 years, 11-12 years, 4 years, 5 years, 4 years, respectively in the following groups: all cases, FPG < or = 10 mmol . L(-1) before treatment and FPG > 10 mmol . L(-1) before treatment, taking single type of SU and taking two types of SU and over. CONCLUSIONS: A MKV model could predict the long-term evolutive process of SFS by a short-term observation; the speed of SFS was related to the degree of DM patients' condition, patients with higher glucose levels prior to treatment would develop SFS faster; but we cannot postpone the development of secondary failure by exchanging SU types.

Changes in brain interleukin-1beta following the coadministration of norfloxacin with biphenylacetic acid in rats.

We sought to determine the changes in brain interleukin-1beta (IL-1beta) following the coadministration of norfloxacin (25 mg/kg, i.p.) with biphenylacetic acid (100 mg/kg, p.o.) in rats. Norfloxacin provoked clonic convulsions in rats treated concomitantly with biphenylacetic acid, a major metabolite of the nonsteroidal anti-inflammatory drug fenbufen. Seizure activity was analyzed by EEG monitoring. Behavioral changes were also monitored. IL-1beta expressions in the prefrontal cortex and hippocampus at different time intervals were studied by reverse transcriptase-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). The epileptiform discharges appeared in all the rats, accompanied with limb twitching and clonic-tonic seizures after administration of norfloxacin coadministered with biphenylacetic acid. Norfloxacin plus biphenylacetic acid-induced convulsions rapidly and transiently enhanced IL-1beta mRNA in the prefrontal cortex and hippocampus. IL-1beta mRNA expression in the prefrontal cortex and hippocampus was detected as soon as 30 min after norfloxacin injection, and decayed to control levels by 6 h. ELISA analysis revealed significant increase of the IL-1beta protein in the prefrontal cortex and hippocampus at 2 h and 6 h. Administration of either norfloxacin or biphenylacetic acid alone did not elicit convulsions and increase in IL-1beta mRNA and protein expressions. The results suggest that the increased IL-1beta expressions in the prefrontal cortex and hippocampus induced by norfloxacin with biphenylacetic acid relate to seizure activities, and that these brain regions play pivotal roles in norfloxacin-induced convulsions.

Assessment of quality of life and relevant factors in elderly diabetic patients in the Shanghai community.

PURPOSE: The study was to assess the quality of life (QOL) of the elderly diabetes mellitus (DM) in Shanghai community and to screen the possible risk factors. METHODS: A total of 951 patients with elderly DM and 1007 elderly subjects with normal glucose tolerance from the same community as control group were enrolled in the study. A door-to-door retrospectively epidemiological survey was used to collect data of QOL, demographic, and diabetic information. The SF-36 instrument (Chinese edition) was used to assess QOL. Multiple stepwise linear regression analysis was also used to identify possible risk factors of QOL in elder DM. RESULTS: In subjects with elderly DM, the general assessment of perceived health was worse, compared with the normal elderly people; the mean score of multi-item dimensions assessment had been decreased, the lowest and highest scores of which on SF-36, respectively, were general health and body pain (ranged from 42.08 to 77.00). Based on the multiple stepwise regression analysis, 23 risk factors entered 9 multiple regressive models (9 dependent variables of which stand for the scores of 8 dimensions and the total score on SF-36) with different amount ultimately. Within the 13 risk factors that affect QOL of the elderly diabetic patients, the negative correlated factors were gender, age, payment ability of medical treatment, tumor, level of fasting plasma glucose (FPG), medicines purchasing channels, diabetic microvascular complications, diabetic macrovascular complications, acute complications, while the positive correlated factors were occupation, income, exercises, knowledge of DM. The multiple correlation coefficient square (R2) represented the above 13 risk factors had a totally 30.5% impact on the entire QOL. CONCLUSIONS: QOL of elderly DM population had significantly been decreased; QOL of the elderly patients in Shanghai community had many risk factors, which on one hand stated the complexity of elderly DM, and on the other hand gave us many useful and practical methods to improve QOL of elderly DM.

In vivo and in vitro chondrotoxicity of ciprofloxacin in juvenile rats.

AIM: To study the relationship between chondrotoxicity and toxicokinetics of ciprofloxacin (CPFX). METHODS: Rats, 4-week old, were treated with CPFX 0, 400, 800, and 1200 mg/kg ig once daily on seven consecutive days. The knee joint cartilage was examined histopathologically. The concentration of CPFX in venous blood and knee joint cartilage samples were determined by a microbioassay using Escherichia coli 44102. The effects of CPFX on proliferation of chondrocytes and secretion of soluble proteoglycans were determined with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and 1,9-dimethylmethylene blue (DMB) assay, respectively. RESULTS: Cartilage was severely lesioned after treatment with CPFX 800 or 1200 mg/kg for 7 d, such as matrix swelling and loss of chondrocytes. The thickness of cartilage was significantly decreased compared with the control group. The maximum serum concentration (Cmax), the area under the plasma concentration-time curve (AUC(0-infinity)), and concentration in cartilage was 16.3 +/- 2.1 mg/L, 97.2 +/- 12.3 mg x h x L(-1), and 13.4 +/- 2.8 microg x g(-1) and 21.8 +/- 2.5 mg/L, 143.1 +/- 22.3 mg x h x L(-1), and 20.3 +/- 3.5 microg x g(-1) after oral administration of CPFX 800 or 1200 mg/kg on d 1, respectively. The data on d 6 were similar with that on d 1. CPFX inhibited proliferation of chondrocytes and the secretion of soluble proteoglycans. CONCLUSION: CPFX concentrations in serum and cartilage could provide a better basis for risk assessment.

Risk factors of adverse drug reaction from non-steroidal anti-inflammatory drugs in Shanghai patients with arthropathy.

AIM: The study was to screen the possible risk factors of adverse drug reaction (ADR) induced by non-steroidal anti-inflammatory drugs (NSAIDs) in Shanghai patients with arthropathy. METHODS: The subjects were randomly selected from a database of outpatients with arthropathy from 9 main hospitals in Shanghai. A door to door retrospective epidemiological survey was used to collect demographic information about the patients, both individual and familial. This included data on their medical histories, lifestyle and dietary habits, history of smoking and alcohol consumption, history of drug therapy, quality of life (QOL) prior to NSAIDs intake, history of NSAIDs therapy and its ADR events, etc. Descriptive statistical methods and univariate analysis were also used to identify possible risk factors for ADRs induced by NSAIDs. RESULTS: Of the 1002 patients surveyed, the average length of NSAIDs intake was 2 years. ADR incidence from different NSAIDs was high, in a range from 46.7 %-66.2 %. In general, the candidate risk factors for ADRs were different for each NSAID. Each of the candidate risk factors were defined and studied in order to evaluate its role in the determination of ADRs from NSAIDs. "Family history of ADRs caused by NSAIDs" was found to be a significant risk factor for the four commonly used NSAIDs: meloxicam, diclofenac, nimesulide, and nabumetone. CONCLUSION: A retrospective epidemiological survey was useful in detecting the risk factors for ADRs caused by NSAIDs. The study found that different NSAIDs might have different risk factors and that there is no single risk factor universally applicable to all NSAIDs.

Safety and efficacy of oral nonsteroidal anti-inflammatory drugs in patients with rheumatoid arthritis : a six-month randomised study.

OBJECTIVE: To monitor the safety and efficacy profile of long-term treatment with diclofenac, nabumetone, meloxicam and celecoxib in patients with rheumatoid arthritis. DESIGN AND METHODS: This randomised, prospective clinical trial included a total of 461 subjects (313 females and 148 males) with clinically diagnosed rheumatoid arthritis. Their average age was 46.9 +/- 14.4 years (range 20-69 years), and the average disease duration was 1333.7 +/- 992.85 days. Subjects were randomly assigned daily administration of one of the following: diclofenac 75-100mg, meloxicam 15mg, nabumetone 1000mg or celecoxib 200mg. During the 6-month treatment period, a monthly patient interview was conducted to evaluate drug efficacy and safety. RESULTS: 407 subjects successfully completed the 6-month treatment. Sixteen patients (12.2%) withdrew from the diclofenac group, 16 (12.2%) from the nabumetone group, 17 (11.8%) from the meloxicam group and five (9.1%) from the celecoxib group. Most withdrawals occurred during the first 3 months of treatment. Reasons for withdrawals in the first three groups were lack of efficacy (44.9%) and adverse effects (38.8%). For the celecoxib group, high cost (80%) was the main reason for withdrawal. Adverse drug reactions to NSAIDs mostly occurred at an early stage of treatment, with an incidence rate of 31.9% for the diclofenac group, 19.9% for the nabumetone group, 25.2% for the meloxicam group, and 7.27% for the celecoxib group. Clinical efficacy rates for the four NSAIDs were positively related to the length of treatment. During the first 4 months, diclofenac, meloxicam and celecoxib showed better efficacy than nabumetone. There were no significant differences in efficacy during the fifth and sixth months. The overall 6-month effectiveness rates were 68.8% for diclofenac, 59.8% for nabumetone, 67.6% for meloxicam and 69.1% for celecoxib. CONCLUSIONS: Adverse drug reactions and their related withdrawals occurred mostly at an early stage of NSAID treatment, so it is crucial to strengthen pharmacovigilance during this period. Among the investigated NSAIDs, celecoxib did not prove to be superior to diclofenac, nabumetone or meloxicam with respect to its efficacy in the treatment of rheumatoid arthritis; however, it did show good patient compliance and safety profiles.

[Meta-analysis on the effect and adverse reaction on patients with osteoarthritis and rheumatoid arthritis treated with non-steroidal anti-inflammatory drugs].

OBJECTIVE: To observe the rate of efficacy and adverse drug reaction of non-steroidal anti-inflammatory drugs (NSAIDs) in the population with osteoarthritis and rheumatoid arthritis, based on available clinical data. METHODS: Using Meta analysis to evaluate the data of effect and safety profile of NSAIDs from 19 articles on randomized clinical trials published from 1990 to 2001 in Chinese journals. The total number of patients enrolled for evaluation on rates of effectiveness and adverse drug reaction were 1 732 and 2 925, respectively. RESULTS: Data on the effect and safety were comparatively heterogeneous among different kinds of NSAIDs. The effective rates (95% CI) were as follows: nabunetone, 66.7% (61.9% - 71.4%); meloxicam, 68.4% (59.2% - 77.6%); naproxen, 64.5% (59.8% - 69.1%); nimesulide, 79.8% (75.7% - 84.0%); ibuprofen, 77.2% (70.7% - 83.8%); diclofenac, 77.1% (69.2% - 85.0%); oxaprozin, 65.8% (59.5% - 72.0%). Rates of adverse drug reaction (95% CI) were as follows: nabunetone, 16.3% (12.5% - 20.0%); meloxicam, 10.2% (4.2% - 16.2%); naproxen, 29.2% (24.8% - 33.6%); nimesulide, 20.2% (16.0% - 24.3%); ibuprofen, 16.7% (14.7% - 18.8%); diclofenac, 19.3% (11.9% - 26.7%); oxaprozin, 12.7% (8.9% - 16.7%) respectively. CONCLUSION: The rates of effect and adverse reaction on patients having osteoarthritis and rheumatoid arthritis with NSAIDs treatment would largely depend on the drugs being used. Within 2 - 8 weeks of treatment, the effective rate and rate of adverse drug reaction with commonly used NSAIDs as nabumeton, meloxicam, etc., were 59.2% - 85.0% and 4.2% - 33.6%, respectively.

Neurotoxicity and toxicokinetics of norfloxacin in conscious rats.

AIM: To study the neurotoxicity and toxicokinetics of norfloxacin (NFLX) in freely moving rats. METHODS: Rats were assigned randomly to four treatment groups that received a single iv dose of 50, 100, 200 mg/kg of NFLX and 0.9 % saline, respectively. Electroencephalogram (EEG) was continuously recorded with a computerized system in freely moving rats. Venous blood samples were collected for determination of the NFLX concentration by microbioassay method with Escherichia coli 441102 as the test strain. Toxicokinetic parameters were determined from serum concentration-time data with the 3p97 program. RESULTS: (1) The epileptiform discharges appeared in all NFLX groups with different latent periods, accompanied with limb twitching and clonic-tonic seizures. The relative total power of the EEG increased. (2) Drug serum concentration-time curves of different doses conformed to a two-compartmental model. The values of clearance, volume of distribution, and terminal half-life were dose-independent, while maximum serum concentrations (Cmax) and the areas under the concentration-time curve (AUC(0-infinity)) of NFLX increased with dosage. (3) The relative total powers of EEG were closely correlated with the administered dose, Cmax as well as AUC(0-infinity). CONCLUSION: The present study established a suitable approach to quantitatively determine central nervous system (CNS) stimulant effect of NFLX. There is a significant correlation between AUC(0-infinity) and the changes of relative total power, which may serve as the index for judgement and prediction of the CNS toxic effect induced by NFLX.

Inhibition by fluoroquinolones of K(+) currents in rat dissociated hippocampal neurons.

The effects of four fluoroquinolones (sparfloxacin, fleroxacin, ofloxacin and levofloxacin) on K(+) currents were investigated in pyramidal neurons acutely isolated from rat hippocampus, to evaluate their relative potencies for inhibiting these channels. Using patch-clamp electrophysiological techniques, we found that all four compounds inhibited the delayed rectifier K(+) current (I(K)), but with different potencies. Sparfloxacin was the most potent compound, displaying an IC(50) value of 6.44 x 10(-4) M, followed by fleroxacin, ofloxacin and levofloxacin, their IC(50) values being 7.09 x 10(-3), 8.42 x 10(-3) and 1.10 x 10(-2) M, respectively. In contrast, the fast transient K(+) current (I(A)) was blocked only by sparfloxacin (IC(50)=2.86 x 10(-3) M) and fleroxacin (IC(50)=4.38 x 10(-3) M), but not by ofloxacin and levofloxacin even at concentrations up to 1 mM. The K(+) current inhibition was reversible after washout of the compounds. Further study is needed to clarify the possible involvement of this novel action in the adverse effects of fluoroquinolones in the central nervous system (CNS).