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Research paper thumbnail of Persistent, severe hypoglycemia-induced organic brain syndrome with neurological sequelae: a case report

General Hospital Psychiatry, 2011

Hypoglycemia is a biochemical abnormality and often the rate-limiting step in the treatment of bo... more Hypoglycemia is a biochemical abnormality and often the rate-limiting step in the treatment of both type 1 and type 2 diabetes mellitus. Left uncorrected and prolonged, hypoglycemia can result in neuronal dysfunction and death, with deficits ranging from measurable cognitive impairments to aberrant behavior, seizures and coma. In this case report, hypoglycemia resulted in severe and persistent neurological (slurred speech and gait abnormalities), cognitive (inattention, disorientation and memory deficits) and behavioral manifestations (verbal hostility and irritability). It highlights the potentially severe neuropsychiatric sequelae following hypoglycemia and is timely for clinicians to be reminded that hypoglycemia prevention needs to be more of a focus of diabetes care in general.

Research paper thumbnail of Molecular modeling studies of poly lactic acid initiation mechanisms

Journal of Molecular Modeling, 2008

The two possible routes to synthesize poly (lactic acid) are polycondensation of the lactic acid ... more The two possible routes to synthesize poly (lactic acid) are polycondensation of the lactic acid and ring opening polymerization (ROP) of the lactide. This work involves molecular modeling of the polymerization initiation mechanisms using different initiators a) H2SO4 for polycondensation b) aluminum isopropoxide for coordination-insertion ROP c)methyl triflate for cationic ROP, and d) potassium methoxide for anionic ROP. For molecular modeling of PLA, we have benchmarked our approach using Ryner’s work on ROP of L-lactide using stannous (II) 2-ethylhexanoate (Sn(Oct)2) and methanol as initiators. Our values of -15.2 kcal mol-1 and -14.1 kcal mol-1 for enthalpy changes in the two steps of activated complex formation match with Ryner’s. Geometric and frequency optimizations have been done on Gaussian’03 using B3LYP density functional theory along with the basis sets LANL2DZ for metal atoms and 6–31G* and 6–31G** for non metal atoms. The kinetic rate constant for each mechanism has been calculated using the values of energy of activation, change in enthalpy, Gibbs free energy, entropy and the partition functions from the Gaussian’03 output. Our polycondensation rate constant value of 1.07 × 10–4 se-1 compares well with 1.51 × 10–4 se-1 as reported by Wang. However, ROP rate constants could not be validated due to lack of experimental data. Figure Cationic Ring Opening Polymerization of L-Lactide

Research paper thumbnail of Persistent, severe hypoglycemia-induced organic brain syndrome with neurological sequelae: a case report

General Hospital Psychiatry, 2011

Hypoglycemia is a biochemical abnormality and often the rate-limiting step in the treatment of bo... more Hypoglycemia is a biochemical abnormality and often the rate-limiting step in the treatment of both type 1 and type 2 diabetes mellitus. Left uncorrected and prolonged, hypoglycemia can result in neuronal dysfunction and death, with deficits ranging from measurable cognitive impairments to aberrant behavior, seizures and coma. In this case report, hypoglycemia resulted in severe and persistent neurological (slurred speech and gait abnormalities), cognitive (inattention, disorientation and memory deficits) and behavioral manifestations (verbal hostility and irritability). It highlights the potentially severe neuropsychiatric sequelae following hypoglycemia and is timely for clinicians to be reminded that hypoglycemia prevention needs to be more of a focus of diabetes care in general.

Research paper thumbnail of Molecular modeling studies of poly lactic acid initiation mechanisms

Journal of Molecular Modeling, 2008

The two possible routes to synthesize poly (lactic acid) are polycondensation of the lactic acid ... more The two possible routes to synthesize poly (lactic acid) are polycondensation of the lactic acid and ring opening polymerization (ROP) of the lactide. This work involves molecular modeling of the polymerization initiation mechanisms using different initiators a) H2SO4 for polycondensation b) aluminum isopropoxide for coordination-insertion ROP c)methyl triflate for cationic ROP, and d) potassium methoxide for anionic ROP. For molecular modeling of PLA, we have benchmarked our approach using Ryner’s work on ROP of L-lactide using stannous (II) 2-ethylhexanoate (Sn(Oct)2) and methanol as initiators. Our values of -15.2 kcal mol-1 and -14.1 kcal mol-1 for enthalpy changes in the two steps of activated complex formation match with Ryner’s. Geometric and frequency optimizations have been done on Gaussian’03 using B3LYP density functional theory along with the basis sets LANL2DZ for metal atoms and 6–31G* and 6–31G** for non metal atoms. The kinetic rate constant for each mechanism has been calculated using the values of energy of activation, change in enthalpy, Gibbs free energy, entropy and the partition functions from the Gaussian’03 output. Our polycondensation rate constant value of 1.07 × 10–4 se-1 compares well with 1.51 × 10–4 se-1 as reported by Wang. However, ROP rate constants could not be validated due to lack of experimental data. Figure Cationic Ring Opening Polymerization of L-Lactide

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