Synthesis and thermal characterization of xylan-graft-polyacrylonitrile.

In this study emulsion polymerization of acrylonitrile using xylan from agricultural waste material (corn cob) and cerium ammonium nitrate was investigated in terms of catalyst acid. Stock ceric solutions were prepared using either nitric or perchloric acid as catalyst. Optimum conditions were determined using different parameters such as reaction time, temperature, and component concentrations. Nitric acid catalyzed reactions resulted in maximum conversion ratio (96%) at 50°C, 1 h where ceric ion, acrylonitrile, xylan, and catalyst concentrations were 21.7 mmol l(-1), 0.5 mol l(-1), 0.2% (w/v), and 0.1 mol l(-1), respectively. However, 83% conversion was obtained with perchloric acid catalysis at 27 °C, 1 h where concentrations were 5.4 mmol l(-1), 0.8 mol l(-1), 0.5% (w/v), and 0.2 mol l(-1), respectively. Copolymer synthesis using perchloric acid was realized at milder conditions than using nitric acid. Thermal analyses of obtained polymers were conducted to characterize copolymers. Results showed that calculated activation energy, maximum degradation temperature, and heat of thermal decomposition changed relying mainly on molecular weight.

Persistent dystonia induced by fluoxetine.

Serotonin-selective re-uptake inhibitors are prescribed widely because they are regarded as having less severe side-effects compared with tricyclics and monoamine oxidase inhibitors. With this popularity, increasing attention has been drawn to their adverse effects. Development of extrapyramidal symptoms has been reported in some patients while taking fluoxetine, a commonly used serotonin-selective re-uptake inhibitor. Here, we report a case of persistent dystonia, thought to be associated with short-term fluoxetine use, which required treatment with botulinum toxin type A.

Separation and direct UV detection of lanthanides complexed with pyridine-2-carboxylic acid by capillary electrophoresis.

Separation and detection of lanthanides by capillary zone electrophoresis in the presence of pyridine-2-carboxylic acid (picolinic acid) as UV-absorbing complexing agent were investigated. The resolution of partially complexed positively charged complexes is improved by using two buffer ligands competing with picolinic acid for metal ions. When hydroxyisobutyric acid (HIBA) and formic acid are used together as competing ligands, this provides complete separation of all 14 lanthanides with good peak shapes. An on-column separation of 14 lanthanides was achieved in only 9 min using 0.8 mmol/l picolinic acid, 10 mmol/l HIBA and 25 mmol/l formic acid at pH 4.7. Determination of lanthanide complexes was performed by direct detection at 210 nm. Detection limits (signal-to-noise ratio=3) are ca. 0.53-0.96 microg/ml.

Separation and direct UV detection of lanthanides complexed with cupferron by capillary electrophoresis.

Separation and detection of lanthanides by capillary zone electrophoresis in the presence of cupferron (N-nitroso-N-phenylhydroxylamine) as UV absorbing complexing agent were investigated. The resolution of partially complexed positively charged cupferron complexes is improved by using a buffer ligand competing with cupferron for metal ions. When hydroxyisobutyric acid (HIBA) is used as buffer and competing ligand, it provides complete separation of all 14 lanthanides with good peak shapes. An on-column separation of 14 lanthanides was achieved in only 7 min using 0.1 mmol/l cupferron, 15 mmol/1 HIBA at pH 4.9. The separation efficiencies for the optimum separation condition are between 77,000 and 208,000 theoretical plates. Determination of lanthanide complexes was performed by direct UV detection at 210 nm. Detection limits (signal-to-noise ratio=3) are ca. 0.24-0.47 microg/ml for lanthanides. Under optimum conditions, the complete separation of thorium and uranium from mixed lanthanides was achieved.

Vacuoliting megalencephalic leukoencephalopathy with subcortical cysts, mapped to chromosome 22qtel.

The leukodystrophies form a complex group of orphan genetic disorders that primarily affect myelin, the main constituent of the brain white matter. Among the leukodystrophies of undetermined etiology, a new clinical entity called "vacuoliting megalencephalic leukoencephalopathy" (VL) was recently recognized. VL is characterized by diffuse swelling of the white matter, large subcortical cysts, and megalencephaly with infantile onset. Family studies in several ethnic groups have suggested an autosomal recessive mode of inheritance. We mapped the VL gene to chromosome 22qtel, within a 3-cM linkage interval between markers D22S1161 and n66c4 (maximum LOD score 10.12 at recombination fraction.0, for marker n66c4; maximum multipoint LOD score 17 for this interval) by genome scan of 13 Turkish families. Linkage analysis under the genetic-heterogeneity hypothesis showed no genetic heterogeneity. No abnormalities were found in three tested candidate genes (fibulin-1 and glutathione S-transferases 1 and 2).

Bilateral middle cranial fossa arachnoid cysts. A case report.

The temporal lobe agenesis syndrome is a rare congenital abnormality. This syndrome frequently has been described in association with arachnoid cysts or abnormal collections of cerebrospinal fluid. Arachnoid cysts develop most frequently in the middle cranial fossa and almost all these cysts are unilateral. Bilateral middle cranial fossa arachnoid cysts are extremely rare and only 9 cases have been reported in the literature. We present an adult case with bilateral arachnoid cysts and temporal lobe agenesis whose mental examination and neurologic assessment is normal. The cysts are demonstrated by CT and metrizamid CT cysternography.

Hemidystonia due to porencephalic cyst. A case report.

We present a 28-year old patient with left hemidystonia since early childhood after head trauma. This is the first report of a patient who had hemidystonia due to CT proven porencephalic cyst involving the caudate nucleus.

High dose anticholinergic therapy (biperiden) in dystonia.

We studied the effect of biperiden in the treatment of dystonia in six patients aged 15-30 years. Five patients had generalized and one patient had segmental dystonia. Biperiden was started at a dose of 2 mg/day and was gradually increased to 40 mg/day in a few weeks. All patients had clinically significant response in varying degrees after a mean follow up of 1.9 years. Three patients showed considerable or dramatic benefit. The 40 mg/day was generally well tolerated. High dose anticholinergic therapy is effective in the management of torsion dystonia.

Thrombosis of intracranial venous sinuses: aetiology, clinical findings and prognosis of 56 patients.

Cerebral venous thrombosis may occur as a complication of infectious and noninfectious processes. In this study 56 patients with angiographically proven cerebral venous thrombosis (CVT) affecting dural sinuses are being reported. Sixty-one percent of the patients were female and 60% were below 30 years of age. Sixty-four percent of the patients had lateral sinus thrombosis and in 26.8% of the cases a septic focus has been found. The diagnosis is established by serial angiography and clinical findings. CVT is not a rare disease while the clinical diagnosis may be difficult because of the variable modes of onset. As the CT findings are found to be non-specific, angiography remains as the best diagnostic tool. Early diagnosis, controlled intracranial pressure, and appropriate antibiotic treatment may reduce the mortality and morbidity rates due to CVT.

[Two treated cases of botulism]. / Tedavi edilmis botulizm vakasi.

Botulism is a severe neuroparalytic disease caused by the neurotoxins of Clostridium botulinum which exert their effects on peripheral nerve junctions. Guillain-Barre syndrome, Myasthenia Gravis, acute Poliomyelitis and diphtheria must be considered in the differential diagnosis. In this study we have discussed two patients who were treated in our clinic, the differential diagnosis and the role of anti-Cholinesterase drugs in the treatment.