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S Meenakshi

Publications and source records attributed to S Meenakshi.

14 recordsLinked to original sources
PubMed1997

Ocular penetration and pharmacokinetics of topical fluconazole.

The high bioavailability and low toxicity of fluconazole, a stable, water-soluble, low-molecular-weight bis-triazole antifungal, makes it a good candidate for consideration as a topical ocular agent. The penetration of fluconazole (0.2%) into the corneas and aqueous humors of New Zealand white rabbits was assayed by gas liquid chromatography (GLC). Peak corneal levels occurred essentially immediately at 5 min in the corneas [debrided, 8.2 +/- 1.2 micrograms/g; nondebrided, 1.6 +/- 0.6 microgram/g; (mean +/- SEM)] and at 15 min after application in the aqueous [debrided, 9.4 +/- 2.3 micrograms/ml; nondebrided, 1.6 +/- 0.6 microgram/ml; (mean +/- SEM)]. Estimating from semilogarithmic plots of the data, the halflife (t1/2) in the debrided eyes was 15 min; in the nondebrided eyes, t1/2 was 30 min. A loading dose of a 20-microliter drop per min for 5 min yielded levels of 59.9 +/- 11.3 micrograms/g (mean +/- SEM) in the debrided corneas and 32.4 +/- 1.9 micrograms/ ml (mean +/- SEM) in the corresponding aqueous humor. A regimen consisting of this loading dose followed by one 20 microliters drop/h for 6 h showed 45.9 +/- 3.5 micrograms/g (mean +/- SEM) in the debrided corneas and 8.8 +/- 1.7 micrograms/ml (mean +/- SEM) in the corresponding aqueous. The same regimen yielded values of 3.1 +/- 0.2 micrograms/g in the nondebrided corneas and 1.3 +/- 0.2 micrograms/ml (mean +/- SEM) in the aqueous. Minimal inhibitory concentrations (MIC) at 24 h for yeasts ranged from < 1.25 to 20 micrograms/ml, for hyaline molds from 2.5 to > 20 micrograms/ml, and dematiaceous molds from < 1.25 to > 20 micrograms/ml. Topical fluconazole exhibits pharmacokinetics and selective MICs that merit further evaluation for its ophthalmic use as a topical antifungal agent.

Administration, Topical↗
PubMed1996

Effects of acetylcholine and carbachol on bovine corneal endothelial cells in vitro.

PURPOSE: To assess the relative cytotoxicity of Miochol (1% acetylcholine and mannitol), Miostat (0.01% carbachol, sodium, potassium, magnesium, and calcium salts), and their individual components using in vitro models of bovine corneal endothelial cells (BCECs). SETTING: Laboratories of the Departments of Ophthalmology and Physiology, The University of Texas Health Science Center, Houston. METHODS: The study was divided into four experiments. Experiment 1 used a confluent model to compare the relative cytotoxicity of Miochol and Miostat on BCECs following short-term exposure. In Experiments 2, 3, and 4, the proliferation model (preconfluent BCECs) was used to detect the possible cytotoxicity of individual components in the commercial preparations of the miotics; i.e., the preconfluent BCECs were exposed to buffered salt solutions containing mannitol (1%, 3%, and 4%), acetylcholine (0.5%, 1%, and 2%), or carbachol (0.1%, 0.5%, and 1%) for 3 hours. RESULTS: Confluent BCECs exposed to Miochol for 30 minutes underwent necrosis and degeneration, while those treated with Miostat did not show any morphological changes. None of the tested solutions except 2% acetylcholine and 1% carbachol caused observable changes in the nuclear densities of BCECs at 24, 72, 120, and 168 hours. CONCLUSION: The major components of Miochol (acetylcholine and mannitol) were found to be nontoxic; the cytotoxicity of the preparation was possibly due to the lack of an appropriate balanced salt solution. These findings may influence the selection of a miotic for use during intraocular surgery.

Acetylcholine↗
PubMed1993

An easy method of spirometry.

Recording of forced expiration from tidal inspiratory level-referred to as Forced Expiratory Capacity (FEC) is a simple and more convenient technique than the conventional forced vital capacity (FVC) manouvre. From FEC tracing, volume expelled in one second (FEC1) and its percentage (FEC1%) can be measured. Such spirometric recording obtained from tidal breathing to Residual Volume (RV) may be referred to as Spirometric Recording at low lung volume. Asthmatics as well as old subjects find this manouvre easier to perform than the conventional FVC technique. FEC recording becomes a simple, reliable and sensitive test for evaluation of early airway obstruction in asymptomatic smokers and therefore may be utilised in clinical and epidemiologic surveys.

Adolescent↗
PubMed1992

Free radicals in myocardial injury: experimental and clinical studies.

The exposure of cardiac cells to OFR generated artificially, showed a marked decrease (p less than 0.01) in cellular utilization of glucose along with a significant decrease in calcium uptake (p less than 0.05). We have also provided evidence for a direct relationship of neutrophil OFR production with the extent of myocardial ischemia in patients of myocardial infarction. Our data provides evidence for implication of OFR in myocardial injury and the pivotal role played by modulators like calcium, ECGF and prostaglandins in potentiating damage to the myocardium.

6-Ketoprostaglandin F1 alpha↗
PubMed1992

Inspiratory spirogram in emphysema.

Bronchodilator therapy on inspiratory indices has not been documented so far. Reduction in inspiratory airflow resistance following inhalation of bronchodilator giving the most consistent and significant changes in emphysematous patients has been demonstrated in the present study.

Administration, Inhalation↗
PubMed1991

Knowledge and concerns of newly diagnosed NIDDM patients in Singapore.

This paper describes the findings of a questionnaire survey of the knowledge and concern of 152 newly diagnosed NIDDM patients presenting at the Government Polyclinic (primary health care centre). This study is part of a project on outpatient diabetic care in Singapore. It was found that 23.7% of the subjects had no education and 51.3% had only primary school education. More than eighty percent of the subjects understood the importance of diet control and weight control in their condition. More than half of the subjects, 61% of males and 52.7% of females were aware that diabetes could not be cured and that once diabetes is controlled, that medication cannot be stopped and that one must still take the medication even if one feels well. Less than 30% knew about the interpretation of blood and urine sugar findings. The two major concerns amongst the subjects were complications and the need for long-term medication. These findings will be incorporated into the next phase of the project where a health education programme for NIDDM patients will be developed and evaluated.

Adult↗
PubMed1983

Effect of cytosol on transport of RNA in vitro during cardiac hypertrophy.

An enhanced RNA-transport activity was observed in vitro from nuclei obtained from animals with cardiac hypertrophy as compared with that of sham-operated controls. The 100 000 g supernatants obtained from hypertrophic hearts stimulated the RNA transport from nuclei of sham-operated controls, and this stimulation was maximum with 40% supernatant. Ca2+- and nucleic acid-dependent ATPase and alkaline phosphatase activities, which may be involved in an energy-dependent transport, were high in nuclei from hypertrophic hearts, and the nuclei of sham-operated animals showed higher activities of these enzymes after incubation with supernatant from hypertrophic hearts, which stimulates the RNA transport in vitro from nuclei of sham-operated animals.

Adenosine Triphosphatases↗
PubMedDate not supplied

Spirometric data in South Indian subjects 60-80 years of age.

Forced expiratory and inspiratory vital capacities and the timed expiratory and inspiratory volumes and forced expiratory and inspiratory flow rates were determined in 50 old men and women between 60-80 years of age. Some of the ratios between expiratory and inspiratory volumes and flow-rates that have been found to be useful for detecting some forms of ventilatory defects are also given.

Aged↗