[Iatrogenic cervical epidural hematoma: case report and review of the literature]. / Heamtoma epidural ccervical yatrogenico. Presentacion de un caso clinico y revision de la literatura.

BACKGROUND: Around 600 spinal epidural hematoma cases have been previously reported. Incidence of paraplegia after epidural anesthesia varies between 0,0005 and 0,02%. Several possible etiologies have been described in the literature, including surgery, trauma, anticoagulant therapy, arteriovenous malformations, pregnancy and lumbar puncture. Spinal and epidural anesthesic procedures represent the tenth most common cause. But in combination with anticoagulant therapy, the forementioned procedures increase its incidence until reaching the fifth most common etiological group. We report the case of an 80 year-old-man with a cervical epidural hematoma who had a good outcome with conservative management. CASE REPORT: 80 year-old-man that developed intense cervicalgia with lower limbs weakness showing complete paraplegia and arreflexia 2 hours after analgesic treatment with epidural cervical infiltration for cervicoartrosis. Cervical MRI showed epidural cervical hematoma between C4 and T1 levels. The patient is transferred to our facilities in order to perform surgery. But after showing fast recovery, medical conservative management was elected. After one month, the patient's condition has improved showing no neurological deficits and complete resorption is seen in MRI. CONCLUSIONS: Nowadays, trend is to perform surgery in patients with spinal hematoma and significant neurological deterioration during the first hours. However, good neurological outcomes can be achieved with conservative management, in well selected patients with non progressive, incomplete and partial deficits. Presently, we can not predict which is the best treatment for each case.

Hematoma epidural cervical yatrogénico. Presentación de un caso clínico y revisión de la literatura / Iatrogenic cervical epidural hematoma: case report and review of the literature

Introducción. En la literatura se recogen alrede­dor de 600 casos de hematomas epidurales espinales. En varios estudios, se afirma que la incidencia de para paresia secundaria a anestesia epidural oscila entre 0,0005-0,02%. Se han descrito numerosas etiologías, incluyendo cirugía, traumatismos, anticoagulación, malformaciones arteriovenosas, embarazo, procesos hematológicos y punción lumbar. Los procedimien­tos anestésicos raquídeos y epidurales representan la décima causa más frecuente. Pero en combinación con el tratamiento anticoagulante, dichos procedimientos aumentan su incidencia hasta alcanzar la quinta causa. Publicamos un caso clínico de hematoma epidural cer­vical yatrogénico en el adulto y el buen resultado obte­nido con tratamiento conservador. Caso clínico. Paciente varón de 80 años, que a las 2 horas de tratamiento analgésico de cervicoartrosis mediante infiltración epidural cervical desarrolla intensa cervicalgia y pérdida de fuerza en extremi­dades inferiores, mostrando paraplejia completa con arreflexia. En RM cervical se evidencia hematoma epidural entre los niveles C4 y T1. Es trasladado a nues­tro centro para cirugía pero ante la rápida recuperación se decide tratamiento médico conservador. Al mes de seguimiento, la situación clínica es similar a la previa, sin secuelas con completa reabsorción del hematoma en (..) (AU)

Background. Around 600 spinal epidural hema­toma cases have been previously reported. Incidence of paraplegia after epidural anesthesia varies between 0,0005 and 0,02%. Several possible etiologies have been described in the literature, including surgery, trauma, anticoagulant therapy, arteriovenous malfor­mations, pregnancy and lumbar puncture. Spinal and epidural anesthesic procedures represent the tenth most common cause. But in combination with anticoagulant therapy, the forementioned procedures increase its inci­dence until reaching the fifth most common etiological group. We report the case of an 80 year-old-man with a cervical epidural hematoma who had a good outcome with conservative management. Case report. 80 year-old-man that developed intense cervicalgia with lower limbs weakness showing com­plete paraplegia and arreflexia 2 hours after anal­gesic treatment with epidural cervical infiltration for (..) (AU)

Studies on the structural variations of pentosan polysulfate sodium (NaPPS) from different sources by capillary electrophoresis.

Commercial pentosan polysulfate sodium salts (NaPPS) are highly sulfated polysaccharides derived from beechwood hemicellulose by sulfate esterification with a Mrel range of 1500-6000. The polysaccharide backbone of NaPPS consists of repeating linear units of 1-4 linked beta-D-xylopyranose with laterally substituted 4-methylglucopyranosyluronic acid units glycosidically linked to the 2 position of the main chain at every 10th xylopyranose unit on average. For many years NaPPS has been used for antithrombotic prophylaxis in Europe and interstitial cystitis in the USA and Australia. More recently NaPPS has found veterinary application for the treatment of osteoarthritis and related conditions in domestic animals and is registered for this use in Australia, New Zealand, Canada, UK, Eire, and several Scandanavian countries. At present the use of NaPPS for human disorders is confined to material manufactured by one company. However, for veterinary applications, NaPPS from three manufactures have been described. Since it is well known that the biological activities of sulfated polysaccharides are dependent on their molecular structures we considered it important to characterise these various NaPPS preparations using an established method of analysis. Unfortunately, traditional analytical techniques such as TLC, OR, UV/Vis spectroscopy, and size exclusion chromatography were incapable of providing structural information which would distinguish these NaPPS preparations from each other. In contrast, a capillary zone electrophoresis (CZE) method facilitated characterisation of the different NaPPS by a highly reproducible fingerprint, using a benzene-1,2,4-tricarboxylic acid buffer (8.75 mmol/L, pH = 4.9) with indirect UV detection (lambda = 217 nm) and a special capillary pre-treatment (1 M NaOH for 1 h at 25 degrees C, then running buffer for 120 min at 25 degrees C applying -20 kV). In the present study more than 20 batches of NaPPS from the three manufacturers have been investigated and compared. Minor batch variations were observed to exist for each manufacturer's product however significant differences were detected between NaPPS synthesised by the different manufacturers. Moreover, some preparations showed fingerprint profiles that indicated a more heterogeneous mixture, probably containing other polysaccharides as well.

Mercury induced modifications in the stereochemistry of the active site through Cys-73 in a serine protease--crystal structure of the complex of a partially modified proteinase K with mercury at 1.8 A resolution.

Proteinese K (PK) isolated from Tritirachium album Limber was crystallized with HgCl2 in excess, under microgravity conditions. The intensity data were collected at 4 degrees C to 1.8 A resolution and the final R-factor after refinement for all the reflections was 0.164. Mercury has been found at two sites with partial occupancies (0.4 and 0.6) which are at distances of 2.48 A and 2.58 A respectively from Cys-73 Sgamma. The Cys-73 in the enzyme structure is located close to the active site residue, His-69. This region is completely buried and is not accessible to the solvent. It is rather tightly packed. Therefore, the binding of mercury distorts the stereochemistry of the neighbouring residues including those belonging to the catalytic triad. As a result of this, the Ogamma of Ser-224 is displaced by 0.6 A which causes the inactivation of proteinase K by increasing the H-bond distance to 3.7 A between Ser-224 Ogamma and His-69 Nepsilon2.

A rare, unreported complication during coronary rotational atherectomy.

We describe a rare and unreported complication during rotational atherectomy of a heavily calcified lesion in the left circumflex artery in a 79-year-old man. The Teflon sheath housing the drive shaft fractured, most probably due to overtightening of the Y-adapter hemostatic valve. As a result, there was intense spasm leading to acute ischemia and the procedure had to be abandoned. This case highlights the importance of using familiar and thoroughly tested hardware in technique-intensive procedures.

Transgenic rat hearts expressing a human cardiac troponin T deletion reveal diastolic dysfunction and ventricular arrhythmias.

OBJECTIVE: Familial hypertrophic cardiomyopathy (FHC) due to mutations of cardiac troponin T (cTnT) is associated with a high frequency of sudden death even in the absence of cardiac hypertrophy. To investigate the causal relationship of cTnT mutations and this particular phenotype, we sought to establish a transgenic rat model for the disease. METHODS: Transgenic rats were generated expressing human wild-type cTnT or two truncated cTnT molecules (del ex16, del ex15/16), resulting from an intron 15 splice donor site mutation previously observed in FHC patients. Transgenic rat hearts were characterized by histology, immunohistochemistry and in the 'working heart'. RESULTS: Human wild-type and del ex16 cTnT were stably expressed and incorporated into the sarcomere of transgenic cardiomyocytes. Del ex16 transgenic rats revealed a lower level of expression (4-5%) than human wt cTnT animals (25-40%). In the 'working heart' model del ex16 hearts exhibited significant systolic and diastolic dysfunction without cardiac hypertrophy. In contrast, human wt cTnT hearts showed improved contractile performance and moderate myocardial hypertrophy. After 6 months of daily physical exercise one del ex16 rat died suddenly and three out of five del ex16 hearts revealed ventricular tachycardia/fibrillation. No arrhythmia was observed in human wt cTnT expressors. Myofibrillar disarray was present in del ex16 hearts after training but not in human wild-type cTnT rats or non-transgenic controls. CONCLUSION: A human cTnT deletion overexpressed in transgenic rats exerts a dominant-negative effect and mimics the phenotype of FHC with diastolic dysfunction and arrhythmias. By contrast, human cTnT wild-type animals reveal a gain of function and cardiac hypertrophy without arrhythmias.

Strategies for capillary electrophoresis: method development and validation for pharmaceutical and biological applications.

This review is in support of the development of selective, reproducible and validated capillary electrophoretis (CE) methods. Focusing on pharmaceutical and biological applications, the successful use of CE is demonstrated by more than 800 references, mainly from 1994 until 1998. Approximately 80 recent reviews have been catalogued. These articles sum up the existing strategies for method development in CE, especially in the search for generally accepted concepts, but also looking for new, promising reagents and ideas. General strategies for method development were derived not only with regard to selectivity and efficiency, but also with regard to precision, short analysis time, limit of detection, sample pretreatment requirements and validation. Standard buffer recipes, surfactants used in micellar electrokinetic capillary chromatography (MEKC), chiral selectors, useful buffer additives, polymeric separation media, electroosmotic flow (EOF) modifiers, dynamic and permanent coatings, actions to deal with complex matrices and aspects of validation are collected in 20 tables. Detailed schemes for the development of MEKC methods and chiral separations, for optimizing separation efficiency, means of troubleshooting, and other important information for key decisions during method development are given in 19 diagrams. Method development for peptide and protein separations, possibilities to influence the EOF and how to stabilize it, as well as indirect detection are considered in special sections.

Quality control of pentosane polysulfate by capillary zone electrophoresis using indirect detection.

Pentosane polysulfate sodium salt (PPS) is a mixture of multiply charged anionic polysaccharides, used for urological treatment. Several constituents of the polysaccharide can be characterized by a highly reproducible fingerprint. In comparison with earlier approaches the separation efficiency has been further improved using an anionic benzene-1,2,4-tricarboxylic acid buffer (8.7 mmol l-1, pH = 4.9) with indirect UV detection (lambda = 217 nm) and a special capillary pretreatment (1 M NaOH for 10 h at 25 degrees C applying -20 kV). The method has been optimized with regard to buffer concentration and pH. The robustness was tested on several capillaries. PPS was separated from all major synthetic impurities such a sulfate, chloride and acetate. Twelve PPS batches from two manufactures were measured and compared.

Crystallization and preliminary X-ray crystallographic analysis of the EGF receptor ectodomain.

Crystallization of the hydrophilic ectodomain of the epidermal growth factor (EGF) receptor has been accomplished in the presence of the ligand EGF. Two different crystal forms have been obtained, one of which was suitable for X-ray analysis. The space group of this form has been assigned to P21212 with unit-cell dimensions of a = 207.4, b = 113.3 and c = 120.4 A. A native data set has been recorded and a heavy-atom search is currently under way. Diffraction from these crystals, however, is limited to low resolution and extensive trials to improve crystal quality further have all failed. To analyse the molecular shape and aggregation of the receptor protein in solution, small-angle X-ray diffraction and dynamic light-scattering techniques have been applied. Synchrotron radiation in combination with cryo-techniques is essential for data collection because of the high solvent content and radiation sensitivity.

Syncope recurrence can better be predicted by history than by head-up tilt testing in untreated patients with suspected neurally mediated syncope.

BACKGROUND: Head-up tilt testing is widely used in the evaluation of patients with suspected neurally mediated syncope. Although it remains unclear which patients require medical therapy to prevent recurrent syncope, most centres initiate empiric medical therapy in all patients in whom neurally mediated syncope has been diagnosed. To determine the natural history of this condition, we followed 80 untreated patients. METHODS: All 80 study patients fulfilled the following inclusion criteria: (1) > or = 1 syncope in the upright position, (2) absence of structural heart disease, (3) unremarkable work-up for other known causes of syncope. Thirty-nine patients had a history of one episode of syncope (group A) and 41 > or = 2 episodes of syncope (group B). Head-up tilting was performed in all patients at 60 degrees for a maximum of 45 min without medical provocation ('Westminster Protocol'). RESULTS: Suspected neurally mediated syncope could be reproduced by tilt testing in four of 39 patients from group A vs 10 of 41 patients from group B (10% vs 24%, P = 0.1). Independent of the result of head-up tilt testing, all patients were prospectively followed without medical therapy. During 23 +/- 8 months follow-up, syncope recurred in four of 39 group A patients vs 22 of 41 group B patients (10% vs 54%, P < 0.05). The incidence of syncope during follow-up was not significantly different between patients with and without positive baseline tilt test (43% vs 30%, P = ns). CONCLUSIONS: (1) 90% of patients with a single episode of syncope remain free of recurrent syncope without medical therapy irrespective of the result of tilt testing. (2) About half of patients with a history of > or = 2 syncopal episodes have recurrent syncope and, thus, may be appropriate candidates for prophylactic medical therapy. (3) Although head-up tilt testing at 60 degrees for up to 45 min does not appear to be useful to predict recurrent syncope in untreated patients, it is still a useful test in its evaluation.

Morphologic development of neonatal rat pinealocytes in monolayer culture.

The morphological development of pinealocytes maintained in monolayer culture, without the neural and humoral effects present in the developing rat has been studied and compared with the development that occurs in vivo. Pinealocytes in 5 day cultures contained organelles that were similar to those present in the pineals of intact 5 day old rats. However, light and dark cells were not noted in culture, and the cultured cells did not have the dense granules noted in vivo. As pinealocytes developed in culture, cytoplasmic processes increased in length and number. By 21 days of culture age, synaptic ribbons were found to have decreased in number, the difference between light cell and dark cell cytoplasm had become more prominent, and dense-cored vesicles had become more numerous, just as in the developing gland in vivo. These results suggest that the complex neural and humoral factors impinging upon the developing neonatal pineal in the intact animal may not be necessary for some aspects of its ultrastructural differentiation.

[Adaptational behaviour of peripheral and central acoustic responses in guinea pigs under the influence of various fractions of an extract from Gingko biloba (author's transl)]. / Adaptationsverhalten peripherer und zentraler akustischer Reizantworten des Meerschweinchens unter dem Einfluss verschiedener Fraktionen eines Extraktes aus Ginkgo biloba

Experimental studies on 114 guinea pigs proved definitely the influence of an extract from Ginkgo biloba batch no. 02 on the acoustic system. Experiments with animals ensured that the adaptation of excitation of the organ of Corti is significantly influenced. This result is shown by registrations of the acoustic nerve potentials in the adapted and nonadapted state. The relation of excitation to adaptation is significantly changed. Under adaptation of excitation an influence on the metabolism of involution is probable. The slow evoked potentials of the acoustic cortex showed no additional influence on the central auditory pathways. With the Ginkgo biloba extract it is probably possible to diminish sound damages caused by white noise. Further experiments on animals are necessary to ensure the application of this pharmaceutical preparation for clinical use.