HPLC in biopharmaceutical investigations of drugs representing pyrimidine derivatives (A review)

Pyrimidine derivatives are widely used for the treatment of viral diseases and cancer. The analysis of pyrimidine derivatives is typically performed using various chromatographic techniques, in particular, reversed-phase high performance liquid chromatography (HPLC). The separation is typically carried out with (7–30)-cm-long C₈ and C₁₈ silica gel columns, mainly at room temperature, and a 1–1.5 ml-min eluent flow rate. The column is eluted in an isocratic or gradient system, and a variety of mobile phases have been proposed. The detection is based on optical absorption or fluorescence measurements, or makes use of mass spectrometry. Various methods of extraction of pyrimidine derivatives from biological samples are discussed, and the corresponding detection limits are presented. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 5, pp. 26–34, May, 2007.     

Blood serum protein sorption on the surface of perfluorocarbon emulsion particles

The amount of protein bound per 1 mL of the perfluorocarbon (PFC) emulsion depends on the emulsifier composition and the particle size. A relationship between the amount of bound protein on the particle surface and the physicochemical parameters of the PFC emulsion interaction with the blood serum, which indirectly characterize the surface properties of the PFC particles, is established. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 12, pp. 40–43, December, 2007.     

Quality of life after total mesorectal excision for rectal cancer

BACKGROUND: After total mesorectal excision for rectal cancer, many surgeons try to avoid an abdominoperineal resection (APR) by performing a transanally double stapled low colo-rectal anastomosis (LRA), frequently without a pouch. This policy is mainly based on the assumption that the quality of life after such LRA is higher than after APR. It has been suggested that a better functional outcome and therefore a higher quality of life might be achieved by a colo-anal J-pouch anastomosis (CPA). The aim of this study was to assess quality of life among disease-free survivors after APR, LRA and CPA. METHODS: The charts of 301 consecutive patients who had undergone surgery for cancer in the middle or lower third of the rectum were analysed. Two hundred four patients were eligible for inclusion. The quality of life among these patients was assessed using one generic (EQ-5D) and two disease-specific questionnaires (EORTC QLQ-C30 and EORTC QLQ-CR38). RESULTS: The response rate was 82%. The median follow-up was 31 months. Overall, quality of life was good but CPA patients had better quality of life scores than APR and LRA patients. This difference was not only due to the better functional outcome but also to the lower incidence of disturbed micturition and sexual problems in the CPA group. CONCLUSION: The quality of life after colo-anal J-pouch anastomosis is better than after abdominoperineal resection (APR) and low colo-rectal anastomosis (LRA). The quality of life after APR is similar to that after LRA.     

Digital imaging with a photostimulable phosphor in the chest of newborns

To evaluate use of a digital photostimulable phosphor imaging system in the neonatal nursery, 150 newborns were divided into three groups of 50. In the first two groups, screen-film and computed radiographs of the chest were obtained at the same radiation exposure; in the third group, computed radiographs were obtained with a 50% dose reduction (half-exposure computed radiographs). All images were blindly evaluated by three readers who scored the quality of visualization of the mediastinum, lung, bone, soft tissues, and endotracheal and nasogastric tubes, and also image density. No statistical differences in visualization of tubes existed among the three groups. Visualization of the mediastinum, lung, bones, and soft tissues was statistically significantly better on computed radiographs than on half-exposure computed radiographs; visualization of the lungs, bones, and soft tissues was statistically significantly better on screen-film radiographs than half-exposure computed radiographs. Image density was statistically better on computed and half-exposure computed radiographs than on screen-film radiographs.     

Procainamide therapy, physical performance and energy expenditure in the Schwartz-Jampel syndrome

The effects of procainamide administration were assessed in a 5-yr-old boy with Schwartz-Jampel syndrome (chondrodystrophic myotonia). Without procainamide the resting metabolic rate was found to be significantly higher than in an age-matched control group. With a serum level of 3.8 mg l-1 procainamide a reduction of the resting metabolic rate of 22% was observed, and times needed to climb stairs and to re-open eyes after forceful contraction (blepharospasm) were significantly reduced.     

Increased bone turnover during the third trimester of pregnancy and decreased bone mineral density after parturition in adolescents as compared to age-matched control patients.

To evaluate the impact of pregnancy on bone, we studied bone turnover at the first (T1) and third (T3) trimester of gestation in 58 adolescents and 28 healthy adolescents who had never been pregnant. Total body (TB) and lumbar spine (LS) bone mineral density (BMD) and body composition were evaluated by dual-energy X-ray absorptiometry in all control patients (C) and after parturition in 28 pregnant patients (G). Paired and unpaired t tests, Mann-Whitney and Pearson correlation tests were used. Bone turnover markers were above the reference range for adult women in more than 80% of the adolescents, with no difference between C and G patients at T1. Increase in urinary N-telopeptide crosslinks of type I collagen and serum bone-specific alkaline phosphatase, markers of bone turnover, was seen during pregnancy ( p < 0.0001). Body composition did not differ between groups, but LS BMD, percentage of expected LS BMD, LS Z-score, percentage of expected TB BMD and TB Z-score were lower in G than C patients ( p < 0.05). TB BMD was positively correlated with LS BMD (r2 = 0.52). The inverse correlations between bone markers and LS BMD suggest that the increased bone turnover during pregnancy probably explains the low bone density after parturition. The impact on future peak bone mass must be studied.     

Isolated complete orbital infarction: a common carotid artery occlusion syndrome

When blood flow through the internal and external carotid arteries is completely interrupted by ipsilateral common carotid artery occlusion, the arterial orbital circulation may be more compromised than the brain supply. We studied a pure and extreme example of this situation in a patient who presented with acute orbital infarction, but no cerebral ischemia on clinical, CT and single-photon emission computerized tomography (SPECT) grounds. Ipsilateral blindness corresponded to retinal, choroidal and optic nerve infarction. The pattern of ophthalmoplegia, with relative sparing of adduction, was more compatible with a muscle than a nerve dysfunction, but a reactive dilated pupil, corneal anesthesia, and orbital pain suggested that the intraorbital branches of the ocular motor nerves and ophthalmic division of the trigeminal nerve were not spared. In addition, signs of widespread ocular ischemia were present. Sequential examinations documented the evolution pattern over 1 year. The absence of an orbital collateral supply from the contralateral external carotid and muscular cervical arteries systems, which contrasted with an adequate middle cerebral artery supply via the contralateral internal carotid artery, may explain this isolated and complete form of orbital ischemia due to common carotid artery occlusion.     

A neonate with bilateral refractory chylothorax--a case report.

A thirty six week gestation male baby weighing three kilogram was born to a twenty five year old mother by spontaneous vaginal delivery. At four hours of life, the baby developed respiratory distress with cyanosis and was admitted to the neonatal intensive care unit. There was clinical and radiological evidence of bilateral pleural effusion. Thoracentesis revealed a transudate. Repeated thoracentesis was necessary to relieve the respiratory distress. Subsequently, multi resistant Klebsiella aerogenes was isolated from the blood. The baby expired due to gram negative sepsis.