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S Mukerji

Publications and source records attributed to S Mukerji.

At least 37 records · Page 2Linked to original sources
PubMed1978

Kinetic characteristics of the glutamate uptake into normal astrocytes in cultures.

Kinetics for uptake and release of glutamate were measured in normal, i.e., nontransformed, astrocytes in cultures obtained from the dissociated, cortex-enriched superficial parts of the brain hemispheres of newborn DBA mice. The uptake kinetics indicated a minor, unsaturable component together with an intense uptake following Michaelis-Menten kinetics. The Km (50 micrometer) was reasonably comparable to the corresponding values in brain slices and in other glial preparations. The Vmax (58.8 nmol min-1 mg-1 protein) was, however, much higher than that observed in glial cell lines or peripheral satellite cells, and also considerably higher than that generally reported for brain slices. The release of glutamate was much smaller than the uptake, and only little affected by an increase of the external glutamate concentration, suggesting a net accumulation of glutamate rather than a homoexchange. Such an intense accumulation of glutamate into normal astrocytes may play a major role in brain metabolism and may help keep the extracellular glutamate concentration below excitatory levels.

Animals↗
PubMed1978

3-Tertiary amino-1-aryloxy- or aryl-propanes and -propan-2-ols and some related compounds.

The synthesis and pharmacological activity of some 3-tertiary amino-1-aryloxy- or 1-aryl-, 1-thiophenoxy and 1-anilino-propan-2-ols and -propanes, particularly those derived from N-phenylpiperazines are described. Effect of substituents (nature/position) on the phenyl ring, the phenoxy ring as well as alteration in the hydroxylic function vis-à-vis the structure-activity relationships (SAR) are discussed. In general, the 1-aryloxy compounds have hypotensive activity--this being more pronounced in those carrying an o-substituent on the phenyl ring, while m and p-substituted derivatives have their effect primarily on the CNS. Variations in the phenoxy moiety do not significantly alter the intrinsic activity. The 1-aryl compounds, on the other hand, have significant CNS activity, which is markedly affected by the substituents on the 1-aryl residue.

1-Propanol↗
PubMed1976

Dotted chromosomes produced in sodium phosphate solution supersaturated with NaHCO3.

Dotted chromosomes were consistently produced in both BrdU and non-BrdU substituted Chinese hamster cells after treatment with 1.0 M Na-phosphate solution, adjusted to pH 9.0 with a supersaturating amount of NaHCO3, and at a temperature of 80--95 degrees C. -- A series of changes in chromosome morphology was produced as the temperature of the solution was progressively increased. In BrdU-treated cells, G-banding and differentially stained sister chromatids were sequentially produced prior to the appearance of dots. In non-BrdU treated cells, only G-banding was produced before dot formation. In general, the patterns of dots correspond to the G-banding patterns. --Chromatids, with uni- or bifilarly BrdU substituted DNA or with normal DNA, required differential temperatures for the production of dots. Since the temperature required for dot formation was always slightly higher than that required for producing differentially stained chromatids, this phenomenon can be used as an important indicator for determining the optimal temperature required for revealing differentially stained chromatids.

Animals↗
PubMedDate not supplied

Management of penetrating laryngotracheal injuries.

BACKGROUND: Penetrating laryngotracheal injuries are uncommon; however, these injuries are associated with significant morbidity and mortality. In an attempt to define the management of penetrating laryngotracheal injuries, we reviewed our experience with these injuries. METHODS: We retrospectively analyzed the records of all patients admitted to a Level I trauma center who required operative management for penetrating laryngotracheal injuries. During the period of this study all patients with penetrating neck injuries were managed according to a protocol of selective exploration. RESULTS: Of fifty-seven patients with penetrating laryngotracheal injury 32 patients sustained gunshot wounds and 25 had stab wounds. The injuries were to the larynx in 24 (42%) and trachea in 33 (58%). Forty-six (81%) had isolated airway injuries and 11 (19%) had combined airway and digestive-tract injuries. Emergent airway management in 32 (56%) patients included: tracheostomy (15), endotracheal intubation (14), and cricothyroidotomy (3). Respiratory distress and subcutaneous crepitus were the commonest clinical findings. Diagnostic evaluation included: laryngoscopy/ tracheoscopy (17), esophagoscopy (12), contrast esophagography (9), angiography (8), and bronchoscopy (3). Repair of laryngotracheal and esophageal injury was performed in the majority of patients. Selected patients with milder laryngotracheal injury did not have tracheostomy performed, with no increase in morbidity or mortality. There were 2 (3.5%) early deaths from associated major vascular injury. CONCLUSION: Mortality can be minimized by aggressive airway control. Endotracheal intubation can be accomplished safely in selected patients with penetrating laryngotracheal injuries. Digestive-tract injuries can often clinically occult and contribute significantly to morbidity and mortality; therefore, early evaluation of the esophagus is vital. Simple repair of laryngotracheal and digestive-tract injuries can be performed safely with good results. In patients with minor injuries, tracheostomy does not appear to be mandatory.

Adolescent↗
PubMedDate not supplied

Ethanol neurotoxicity. 1. Direct effects on replicating astrocytes.

Experiments were conducted to investigate the direct effects of ethanol on the DNA, RNA and protein content of rapidly growing astroglia. Astrocyte progenitor cells obtained from the neopallia of newborn mice were grown for 6 days in primary culture and then exposed continuously to ethanol (0.0, 0.06, 0.12 or 0.24 g/dl) for 11 days. The in vitro exposure period corresponds to the period of peak astroglial replication and growth in the mouse brain growth spurt in situ (postnatal days 6 to 17). DNA, RNA and protein contents were all significantly different in ethanol-exposed astroglial cultures compared to controls (p less than 0.0005) and there was an unexpected, but highly consistent, concentration-related pattern to this effect, namely, an increased content relative to controls at the lowest ethanol concentration, and a progressive decrease in content with increasing ethanol concentrations. Our data indicate that different cell processes contributing to growth are more vulnerable to ethanol's toxicity than others. RNA and protein contents are reduced to a greater degree and at lower ethanol concentrations than is DNA content. The "growth-promoting" effect seen in these in vitro studies emphasizes the fact that factors which are secondary to alcohol consumption contribute significantly to the alcohol-related brain growth deficits which are seen in vivo. Ethanol acting alone appears to exert a "growth-impairing" effect only at high concentrations.

Animals↗