Biomedical subjects

Mei Lin

Publications and source records attributed to Mei Lin.

At least 19 recordsLinked to original sources

PubMed2025

ABO exon polymorphisms are related to ischemic stroke in a Chinese Han population.

BACKGROUND: Recent research have underscored the relation of ABO blood group system to cerebrovascular disorders predisposition. The present investigation endeavors to delve into the relationship between ABO polymorphisms and ischemic stroke (IS) risk. METHODS: A cohort of 646 IS patients and 649 matched healthy controls was recruited. Genotyping of five SNPs within ABO were conducted by Agena MassARRAY platform. Logistic regression models were employed to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Additionally, SNP-SNP interaction was assessed by multifactor dimensionality reduction (MDR) method. Furthermore, Analysis of Variance (ANOVA) was utilized to explore the association between genotypes and blood lipid profiles. RESULTS: The study identified an elevated IS risk associated with rs8176740 and rs8176720 in the overall population. Notably, ABO rs8176720 emerged as the most informative single-locus model for IS susceptibility. These variants were related to an elevated IS risk, specifically in female subjects, the subgroup aged > 64 years, non-smokers, drinkers or non-drinkers. Moreover, rs8176749 and rs8176745 were associated with red blood cell count levels and total bilirubin levels. CONCLUSION: This study firstly demonstrated the association of ABO rs8176740 and rs8176720 with IS incidence, which increased the understanding regarding the effect of ABO on IS pathogenesis.

Aged↗

PubMed2007

Structure and release behavior of PMMA/silica composite drug delivery system.

The preparation, characterization, and in vitro release of aspirin from polymethylmethacrylate (PMMA)/silica composites prepared via a sol-gel route are reported. The in vitro drug release test revealed that the release rate of aspirin in PBS increased with the silica content in the composites; on the contrary, the increase of the content of 3-(trimethoxysilyl) propyl methacrylate (MSMA), a coupling agent, decreased the drug release rate. The drug release rate/composite structure relationship was studied using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and swelling ratio (SR) measurement. The results indicated that the interface between polymer matrix and inorganic fillers has significant influence on the drug release behavior of the composite materials. In addition, models of mass transfer based on Fickian diffusion law at constant temperature and pressure were employed to analyze the results of the in vitro drug release experiments. The drug release behaviors of the composite samples fitted well with the Fickian diffusion model. The values of k, which is in direct proportion to drug release rate, increased with the increasing content of silica while decreased with that of MSMA in the composite samples.

Aspirin↗

PubMed2007

Stroke associated with diabetes among Canadians: sex and age differences.

OBJECTIVE: To determine the age and sex variations in the relationship between diabetes and stroke. METHODS: This analysis was based on data from 61,327 Canadians > or =45 years of age who participated in the Canadian Community Health Survey in 2000-2001. Logistic regression analysis was conducted to evaluate the association between diabetes and stroke, and effect modification by age and sex. RESULTS: The association between diabetes and stroke was stronger in the 45- to 64-year age group than the > or =65 year age group in men but not in women. The increased risk of stroke associated with diabetes was much stronger in men (adjusted OR = 3.86, 95% CI = 2.44-6.13) than in women (adjusted OR = 1.63, 95% CI = 0.88-2.99), and this difference was only observed in the younger age group. The results were similar after further adjustment for hypertension and heart disease. CONCLUSIONS: There is a stronger association between stroke and diabetes in men than in women 45-64 years of age, suggesting men are more susceptible to stroke than women when they have diabetes.

Age Distribution↗

PubMed2006

Development of a liquid chromatography/tandem mass spectrometry assay for the determination of bestatin in rat plasma and its application to a pharmacokinetic study.

Bestatin is a low molecular weight aminopeptidase inhibitor originally isolated from culture filtrates of Streptomyces olivoreticuli. We have developed a sensitive, specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the quantitative determination of bestatin in rat plasma using granisetron as the internal standard. The analyte and internal standard were isolated from 50 microL plasma samples by solid phase extraction (SPE). Reverse-phase HPLC separation was accomplished on a Lichrospher C18 column (4.6 mm x 50 mm, 5 microm) with a mobile phase composed of methanol-water-formic acid (70:30:0.5, v/v/v) at a flow rate of 0.8 mL/min. The method had a chromatographic total run time of 3 min. A Varian 1200L electrospray tandem mass spectrometer equipped with an electrospray ionization source was operated in selected reaction monitoring (SRM) mode with the precursor-to-product ion transitions m/z 309.2-->120.0 (bestatin) and 313.4-->138.0 (granisetron) used for quantitation. The method was sensitive with a lower limit of quantitation (LLOQ) of 5 ng/mL, with good linearity (r2 >or= 0.999) over the linear range of 5-2000 ng/mL. All the validation data, such as accuracy, precision, and inter-day repeatability, were within the required limits. The method was successfully applied to pharmacokinetic study of bestatin in rats.

Animals↗

PubMed2006

Development and validation of a selective and robust LC-MS/MS method for high-throughput quantifying rizatriptan in small plasma samples: application to a clinical pharmacokinetic study.

An analytical method based on liquid chromatography with positive ion electrospray ionization (ESI) coupled to tandem mass spectrometry detection (LC-MS/MS) was developed for the determination of a potent 5-HT(1B/1D) receptor agonist, rizatriptan in human plasma using granisetron as the internal standard. The analyte and internal standard were isolated from 100 microL plasma samples by liquid-liquid extraction (LLE) and chromatographed on a Lichrospher C18 column (4.6mm x 50mm, 5 microm) with a mobile phase consisting of acetonitrile-10mM aqueous ammonium acetate-acetic acid (50:50:0.5, v/v/v) pumped at 1.0 mL/min. The method had a chromatographic total run time of 2 min. A Varian 1200 L electrospray tandem mass spectrometer equipped with an electrospray ionization source was operated in selected reaction monitoring (SRM) mode with the precursor-to-product ion transitions m/z 270-->201 (rizatriptan) and 313.4-->138 (granisetron) used for quantitation. The assay was validated over the concentration range of 0.05-50 ng/mL and was found to have acceptable accuracy, precision, linearity, and selectivity. The mean extraction recovery from spiked plasma samples was above 98%. The intra-day accuracy of the assay was within 12% of nominal and intra-day precision was better than 13% C.V. Following a 10mg dose of the compound administered to human subjects, mean concentrations of rizatriptan ranged from 0.2 to 70.6 ng/mL in plasma samples collected up to 24h after dosing. Inter-day accuracy and precision results for quality control samples run over a 5-day period alongside clinical samples showed mean accuracies of within 12% of nominal and precision better than 9.5% C.V.

Adult↗

PubMed2006

Rapid determination of granisetron in human plasma by liquid chromatography coupled to tandem mass spectrometry and its application to bioequivalence study.

A simple, sensitive and rapid method for analysis of granisetron in human plasma, utilizing liquid chromatography tandem mass spectrometry (LC-MS/MS), has been developed and validated to satisfy FDA guidelines for bioanalytical methods. The analyte and internal standard (IS) were isolated from 100microl plasma samples by liquid-liquid extraction (LLE). A Varian 1200l tandem mass spectrometer equipped with an electrospray ionization source was operated in selected reaction monitoring (SRM) mode with the precursor-to-product ion transitions m/z 313.4/138 for granisetron and m/z 270/201 for the IS used for quantitation. The assay exhibited a linear dynamic range of 0.02-20ng/ml for granisetron in human plasma. The lower limit of quantification (LLOQ) was 0.02ng/ml with a relative standard deviation of less than 15%. The mean extraction recovery from spiked plasma samples was 97.9%. The intra-day accuracy of the assay was within 10% of nominal and intra-day precision was better than 15% C.V. A run time of 2.0min for each sample made it possible for high-throughput bioanalysis. The method was employed in a bioequivalence study of two formulations of granisetron hydrochloride 1mg rapidly disintegrating tablets/1mg capsules.

Administration, Oral↗

PubMed2006

An evaluation on the efficacy and safety of amlexanox oral adhesive tablets in the treatment of recurrent minor aphthous ulceration in a Chinese cohort: a randomized, double-blind, vehicle-controlled, unparallel multicenter clinical trial.

OBJECTIVE: The objectives of this study were to clinically determine the topical efficacy and safety of amlexanox oral adhesive tablets in the treatment of recurrent minor aphthous ulcerations (MiRAU) in a Chinese cohort. STUDY DESIGN: A randomized, double-blind, vehicle-controlled, unparallel multicenter clinical trial was carried out. The tablets were applied by subjects themselves 4 times a day for 5 days. Four parameters (pain scale, size change, degree of erythema and exudation, and efficacy index) were recorded both before (baseline) and during the trial (on the morning of days 4 and 6). RESULTS: There were 104 and 108 subjects who fulfilled the trial in the amlexanox group and the vehicle-control group, respectively. Group differences for all parameters but degree of erythema and exudation of day 4 were statistically significant both for the day 4 visit and the day 6 visit (P < .05). No systemic side effects were reported. CONCLUSIONS: Amlexanox oral adhesive tablets are effective and safe in reducing aphthous ulcer pain and lesion size, as well as erythema and exudation in this Chinese cohort.

Adhesives↗

PubMed2006

Labor dystocia and its association with interpregnancy interval.

OBJECTIVE: The purpose of this study was to evaluate the prevalence of labor dystocia and its association with interpregnancy interval. STUDY DESIGN: We linked the birth data for Michigan infants who were born from 1994 to 2002 with the hospital discharge data. The International Classification of Diseases (9th revision, clinical modifications, ICD-9-CM) codes that indicate labor dystocia were identified by a physician panel and classified as functional and mechanical dystocia. We estimated the prevalence of labor dystocia and used stratified and logistic regression analyses to evaluate labor dystocia in relation to interpregnancy interval, controlling for other reproductive risk factors. RESULTS: Overall, 20.8% of the births involved labor dystocia (11.1% functional; 12.5% mechanical). Both functional and mechanical dystocia were more prevalent in first births than in subsequent births; mechanical dystocia was more prevalent in multiple births than in singleton births. In singleton births to multiparous mothers, labor dystocia was associated with the interpregnancy interval in a dose-response fashion. Compared with an interpregnancy interval of <2 years, the adjusted odds ratios that was associated with interpregnancy intervals of 2 to 3, 4 to 5, 6 to 7, 8 to 9, and 10+ years were 1.06 (95% CI, 1.04-1.08), 1.15 (95% CI, 1.12-1.17), 1.25 (95% CI, 1.21-1.29), 1.31 (95% CI, 1.26-1.37), and 1.50 (95% CI, 1.45-1.56), respectively, when we controlled for other reproductive risk factors. Functional dystocia was associated more strongly with interpregnancy interval than mechanical dystocia. CONCLUSION: Labor dystocia is common. In singleton births to multiparous mothers, labor dystocia increased with interpregnancy interval.

Adolescent↗

PubMed2006

Quantitative determination of MCC-555, a novel insulin sensitizer in beagle dog plasma by high-performance liquid chromatography with fluorescence detection.

A sensitive high-performance liquid chromatographic method with fluorescence detection has been developed for determination of MCC-555 (5-[[6-(2-fluorbenzyl)-oxy-2-naphy] methyl]-2,4-thiazolidinedione) in beagle dog plasma. Sample preparation was done by protein precipitation with acetonitrile and a synthetic intermediate of MCC-555 (5-[[6-(2-fluorbenzyl)-oxy-2-naphy] methylene]-2,4-thiazolidinedione) was used as the internal standard (IS). The isocratic mobile phase consisted of acetonitrile-10 mmol/l sodium phosphate buffer (pH 4.5) (65:35, v/v) was delivered at a flow rate of 1 ml/min to a Kromasil C(18) reversed-phase column (250 mm x 4.6 mm, 5 microm). The compounds were detected by fluorescence detection, using an excitation wavelength of 232 nm, and emission wavelength of 352 nm. Calibration curves of MCC-555 were linear in the concentration range of 0.005-2.0 microg/ml. Intra- and inter-day precision ranged from 3.4 to 5.4% and 3.0 to 8.8%, respectively. No endogenous interferences were observed with either MCC-555 or IS. The assay is simple, economical, precise, and is directly applicable to pharmacokinetic studies in beagle dogs involving three dose administrations.

Animals↗

PubMed2006

Chronic sinusitis and arterial hypertension in a national population health survey.

BACKGROUND: To determine if sinusitis is associated with arterial hypertension in the Canadian population. METHODS: Complex survey design incorporating stratification, multiple stages of selection, and unequal probabilities of selection of respondents. Cross-sectional data from 52,992 subjects (25,324 males and 27,668 females) 20-64 years of age who participated in the second cycle of the National Population Health Survey (NPHS), conducted in 1996-1997. All these individuals were asked if they had certain chronic health conditions, that had lasted or were expected to last 6 months or more, including sinusitis and high blood pressure. RESULTS: Overall, males with sinusitis were just over 2% more likely to have hypertension (9.3% vs. 7.1%) whereas the difference was 4% for women (11.8% vs. 7.6%). Adjusted for age, region, habitation, immigrant status, household size, number of bedrooms, income adequacy, education level, smoking status, alcohol consumption, regular exercise and body mass index, the adjusted odds ratio for females was 1.42 (95% CI 1.04, 1.95). CONCLUSIONS: Reported sinusitis is associated with hypertension but only in women. Mechanisms linking upper respiratory disorders to hypertension merit investigation.

Adult↗

PubMed2006

Case-control study of vaccination history in relation to pertussis risk during an outbreak among school students.

BACKGROUND: Between September and December 2003, an outbreak of pertussis occurred in Cass County, MO, mostly among adolescent school children. METHODS: We conducted a 1:2 matched case-control study among school children and used conditional logistic regression to evaluate risk factors for pertussis, including the total number of vaccine doses received, age at administration of each dose of vaccine and the type of vaccine (whole cell or acellular). RESULTS: Of all 127 pertussis cases reported in this outbreak, the majority were adolescents (10-19 years of age, 50%) and adults (20 years or older, 22%); only 10% were infants and children less than 5 years of age. Because the focus of our investigation was on school-aged children, we enrolled 237 students (79 cases and 158 controls) in our study. Students missing at least one dose of the vaccine had higher risk for pertussis than those who received all 5 doses (odds ratio [OR], 2.36; 95% confidence interval [CI], 1.17-4.77). Early administration of the fifth dose of the vaccine at age 4 years was significantly associated with risk for pertussis compared with vaccination at age 5 years (adjusted OR, 2.45; 95% CI, 1.16-5.16). A short time interval (<36 months) between the fourth and fifth doses of the vaccine also tended to increase the risk for pertussis, although this association was not statistically significant. The type of vaccine was not a significant risk factor. CONCLUSION: Administering all 5 doses of pertussis vaccine and the fifth dose at age 5 years with at least 36 months between the fourth and fifth doses provided the best protection against pertussis among children and adolescents in this outbreak.

Adolescent↗

PubMed2006

Personal hygiene and methicillin-resistant Staphylococcus aureus infection.

Methicillin-resistant Staphylococcus aureus (MRSA) infections outside the healthcare setting are an increasing concern. We conducted a case-control study to investigate an MRSA outbreak during 2002-2003 in a Missouri prison and focused on hygiene factors. Information on sociodemographic characteristics, medical history, and hygiene practices of study participants was collected by interview and medical record review. Logistic regression was used to evaluate MRSA infection in relation to hygiene factors individually and as a composite hygiene score; potential confounding factors were controlled. Selected MRSA isolates were analyzed by pulsed-field gel electrophoresis (PFGE). MRSA infection was significantly associated with a low composite hygiene score. Transmission among prison inmates appeared to be responsible for this outbreak. PFGE analysis showed that isolates were indistinguishable and associated with community-onset MRSA infections in other US prisons. Improving hygiene practices and environmental conditions may help prevent and interrupt future MRSA outbreaks in prison settings.

Adult↗

PubMed2006

[Correlation between clinical manifestation and salivary secretion of xerostomia patients].

OBJECTIVE: To observe the general status, subjective syndromes, objective signs and salivary secretion of xerostomia patients for studying their correlations. METHODS: Eighty patients' clinical data were collected and classified according to certain standards. The salivary secretion including the unstimulated whole saliva (UWS) and stimulated whole saliva (SWS) in five minutes was measured by spit method. RESULTS: Decreased UWS was the main presentation of xerostomia which accouted for seventy five percents. Significantly statistical correlation were found between the decreased UWS and the dry mouth signs but not the age, sex and the accompany syndromes. CONCLUSION: Xerostomia has a high prevalence in middle-aged women with a long course and obvious regularity. The decreased UWS is the main presentation which was not caused by physiological changes of salivary glands and has no correlation with many clinical manifestations.

Adult↗

PubMed2006

[The change of platelet derived growth factor in patients with obstructive sleep apnea-hypopnea syndrome].

OBJECTIVE: To observe the change of platelet derived growth factor-B (PDGF-B) in obstructive sleep apnea-hypopnea syndrome (OSAHS) patients, and to explore the relationship of PDGF-BB, OSAHS and complicated cardiovascular diseases. METHODS: The levels of serum PDGF-BB in 40 OSAHS patients and 20 healthy controls were measured by enzyme-linked immunosorbent assay (ELISA) method. The levels of PDGF-B mRNA in peripheral blood mononuclear cells were measured by reverse transcription polymerase chain reaction (RT-PCR). RESULTS: The serum levels of PDGF-BB and the levels of PDGF-B mRNA in peripheral blood mononuclear cells were significantly higher in OSAHS group [mild, moderate, severe level was (477 +/- 115), (736 +/- 126), (1,046 +/- 137) ng/L, and (0.7 +/- 0.1), (1.0 +/- 0.2), (1.3 +/- 0.2) respectively] than those in control group [(151 +/- 19) ng/L, 0.4 +/- 0.1, F = 102.59, 58.75, P < 0.01] and PDGF-BB related with severity of OSAHS. There was a positive correlation between PDGF-BB level and AHI as well as average angiosthenia (P < 0.05). Also, there was a positive correlation between PDGF-BB level and percentage of time spent when oxygen saturation lower than 90% (SLT90%) (P < 0.05). There was a negative correlation between PDGF-BB and average saturation of blood oxygen as well as lowest saturation of blood oxygen (P < 0.05). After nCPAP, the levels of PDGF and PDGF-B mRNA in OSAHS patients [before treatment: (1,046 +/- 137) ng/L, (1.3 +/- 0.2), after treatment: (699 +/- 130) ng/L, (0.7 +/- 0.2)] reduced significantly, but still higher then those of control group [(151 +/- 19) ng/L, 0.4 +/- 0.1, F = 82.21, 154.24, P < 0.01]. CONCLUSION: The level of PDGF-BB in OSAHS is increased increases, which may play a role in the pathophysiology of OSAHS and complicated cardiovascular diseases.

Adult↗

PubMed2006

[The relationship between tumor necrosis factor-alpha gene promoter polymorphism and obstructive sleep apnea-hypopnea syndrome].

OBJECTIVE: To investigate the relationship between tumor necrosis factor-alpha (TNF-alpha) gene promoter polymorphism and obstructive sleep apnea-hypopnea syndrome (OSAHS). METHODS: The plasma TNF-alpha level of OSAHS group and non-OSAHS group was detected by enzyme-linked immunosorbent assay (ELISA). Eighteen patients with severe OSAHS were treated with continuous positive airway pressure (CPAP) for 1 month, and the serum levels of TNF-alpha was also measured. The genotypes of TNF-alpha gene promoter polymorphism were determined by polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP). The genotypes and allele of the polymorphisms were compared between OSAHS group and non-OSAHS group. The effects of the polymorphisms in OSAHS group on body mass index (BMI), neck circumference (NC), waist/hip rate (WHR), polysomnography (PSG), systolic blood pressure (SBP), diastolic blood pressure (DBP) were analyzed. RESULTS: The plasma level of TNF-alpha in OSAHS group was higher than the control group [(12.3 +/- 3.62) ng/L and (8.59 +/- 1.62) ng/L, respectively, t = 7.716, P < 0.01]. CPAP significantly decreased the serum levels of TNF-alpha, but its level (10.31 +/- 1.91) ng/L was still higher in the patients than the control group. The frequencies of TNF-alpha AA/AG genotype in OSAHS group (frequencies 31/76, 40.8%) was higher than the control one (frequencies 7/42, 16.7%) (chi(2) = 7.485, P < 0.05). Statistical analysis showed that OSAHS group had a significantly higher TNF-alphaA allele frequency (frequencies 39/152, 25.7%) than that of the control one (frequencies 39/152, 9.5%) (chi(2) = 8.830, P < 0.01). The OSAHS patients with AA/AG genotype had significantly higher serum levels of TNF-alpha, NC, WHR and aphea-hypopnea index [(13.39 +/- 3.71) ng/L, (45.2 +/- 4.2) cm, (0.91 +/- 0.12), and (34.8 +/- 15.6)/h, respectively] than those with GG genotype group [(11.09 +/- 3.54) ng/L, (42.7 +/- 4.9) cm, (0.85 +/- 0.12) and (26.4 +/- 12.3)/h, respectively] (t = 2.725, 2.278, 2.150, 2.609 respectively, P < 0.05 or < 0.01). The L SaO(2) (the lowest SaO(2)) in patients with AA/AG genotype [(78.8 +/- 10.9)%] was significantly lower than that in patients with GG genotype [(83.4 +/- 8.6)%] (t = 2.039, P < 0.05). There was no significant difference in BMI, SBP and DBP. CONCLUSION: The presence of the TNF-alphaA allele may be associated with susceptibility to OSAHS, and it maybe an important candidate gene for OSAHS.

Adult↗

PubMed2005

The association between allergy and rheumatoid arthritis in the Canadian population.

BACKGROUND: Antagonism between Th1 and Th2 lymphocyte mediated responses has been proposed to explain the observed 20th Century population increase in Th2 mediated allergic disease and reciprocal decrease in infectious disease, which stimulates a Th1 mediated response. OBJECTIVE: To determine if Th1/Th2 antagonism would be consistent with associations between non-infectious diseases, we tested the hypothesis that the population prevalence of Th2 mediated allergies is inversely related to the prevalence of Th1 mediated rheumatoid arthritis. METHODS: The analysis was based on data from the Canadian Community Health Survey conducted by Statistics Canada in 2000-2001 of those at least 12 years of age from 125,129 households. Each subject was asked if he or she had certain chronic health conditions that had been diagnosed by a health professional. Logistic regression models were used to evaluate the association between rheumatoid arthritis and allergies with consideration of other important variables. RESULTS: Allergy history was positively related to the prevalence of rheumatoid arthritis both in women (adjusted odds ratio (OR): 1.57, 95% CI: 1.43, 1.73) and in men (adjusted OR: 1.55, 95% CI: 1.36, 1.77). CONCLUSIONS: The reported population prevalences of allergies and rheumatoid arthritis were positively associated and not explained by Th1/Th2 anatagonism suggesting that this mechanism may only be applicable to the association between an infectious and an immunologic disease. Mechanisms accounting for positive associations between immunologic diseases deserve further study.

Adolescent↗

PubMed2005

The association between allergy and diabetes in the Canadian population: implications for the Th1-Th2 hypothesis.

T-lymphocytes may preferentially differentiate towards a Th1 subtype, which is thought to be involved in the autoimmune aspects of diabetes, or a Th2 subtype, which is thought to mediate allergic disease. The activation of one subtype is thought to inhibit the other. To determine if diabetes is less common among those with allergic disease, consistent with the postulated TH1/Th2 paradigm, we used data from the 2000-2001 Canadian Community Health Survey of those at least 12 years of age from 125,159 households. Diabetes requiring insulin was reported in 1% whether or not allergies were reported. The crude odds ratio between diabetes and allergies for the entire population was 1.06 (95% confidence interval (CI): 0.90, 1.24). Adjusted for household size, number of bedrooms, immigrant status, income adequacy, educational level, smoking status, alcohol drinking status, regular exercise, and age, there was a positive association between allergy and diabetes with an odds ratio of 1.25 (95% CI: 1.06, 1.49). These results do not provide evidence for the existence of the Th1/Th2 paradigm as a determinant of disease patterns in the general population.

Adolescent↗

PubMed2005

Compatibility and stability of dexamethasone sodium phosphate and ketamine hydrochloride subcutaneous infusions in polypropylene syringes.

The stability of ketamine hydrochloride injection and dexamethasone sodium phosphate injection, when mixed and stored in polypropylene syringes, was studied. Formulations containing ketamine hydrochloride (50 mg or 600 mg) and dexamethasone sodium phosphate (1 mg) in 0.9% sodium chloride injection (to 14 ml) were prepared and stored at 4 degrees C, 23 degrees C, and 37 degrees C, under normal fluorescent light conditions, for 192 hours. The concentrations of the drugs were determined at 0, 2, 4, 8, 24, 48, 96, and 192 hours using a validated high-pressure liquid chromatography method. The pH, color, and visible particles of each solution were also assessed at each time point. All formulations tested maintained more than 98% of the initial concentrations of both drugs, and no degradation products were detected. The solutions remained clear and colorless and the pH varied within 0.05 units throughout 192 hours. The results indicate that, at the concentrations studied, combinations of ketamine hydrochloride and dexamethasone sodium phosphate in 0.9% sodium chloride injection were physically and chemically stable for at least 192 hours (8 days) when stored in polypropylene syringes.

Complex Mixtures↗