Intersegmental synchronization of spontaneous activity of dorsal horn neurons in the cat spinal cord

Extracellular recordings of neuronal activity made in the lumbosacral spinal segments of the anesthetized cat have disclosed the existence of a set of neurons in Rexed's laminae III-VI that discharged in a highly synchronized manner during the occurrence of spontaneous negative cord dorsum potentials (nCDPs) and responded to stimulation of low-threshold cutaneous fibers (<1.5x T) with mono- and polysynaptic latencies. The cross-correlation between the spontaneous discharges of pairs of synchronic neurons was highest when they were close to each other, and decreased with increasing longitudinal separation. Simultaneous recordings of nCDPs from several segments in preparations with the peripheral nerves intact have disclosed the existence of synchronized spontaneous nCDPs in segments S1-L4. These potentials lasted between 25 and 70 ms and were usually larger in segments L7-L5, where they attained amplitudes between 50 and 150 micro V. The transection of the intact ipsilateral hindlimb cutaneous and muscle nerves, or the section of the dorsal columns between the L5 and L6, or between the L6 and L7 segments in preparations with already transected nerves, had very small effects on the intersegmental synchronization of the spontaneous nCDPs and on the power spectra of the cord dorsum potentials recorded in the lumbosacral enlargement. In contrast, sectioning the ipsilateral dorsal horn and the dorsolateral funiculus at these segmental levels strongly decoupled the spontaneous nCDPs generated rostrally from those generated caudally to the lesion and reduced the magnitude of the power spectra throughout the whole frequency range. These results indicate that the lumbosacral intersegmental synchronization between the spontaneous nCDPs does not require sensory inputs and is most likely mediated by intra- and intersegmental connections. It is suggested that the occurrence of spontaneous synchronized nCDPs is due to the activation of tightly coupled arrays of neurons, each comprising one or several spinal segments. This system of neurons could be involved in the modulation of the information transmitted by cutaneous and muscle afferents to functionally related, but rostrocaudally distributed spinal interneurons and motoneurons, as well as in the selection of sensory inputs during the execution of voluntary movements or during locomotion.

Validation of the 13c-urea breath test for the initial diagnosis of helicobacter pylori infection and to confirm eradication after treatment

OBJECTIVES

the breath test with 13C-urea (UBT) is a method widely used in Spain, but its diagnostic accuracy has not been evaluated in a clinical trial until now. Our objective was to validate the UBT (TAU-KIT) both as an initial diagnostic method for the detection of H. pylori infection and as a method to confirm eradication.

METHODS

a multi-centre study in 7 Spanish hospitals was performed. A group of dyspeptic patients who had not previously received eradication treatment was included, and a second group of patients with gastric ulcer or upper gastrointestinal bleeding due to peptic ulcer was also included (eradication of H. pylori was confirmed 6 to 8 weeks after treatment completion with omeprazole, clarithromycin and amoxycillin). In both groups an endoscopy was performed with biopsies for histology and rapid urease test. Patients were considered infected if both tests yielded positive results, and not infected when both tests were negative. The UBT 13C-urea (TAU-KIT, Isomed S.L., Madrid, Spain) was performed with citric acid and 100 mg of 13C-urea. The pathologist and persons responsible for endoscopy, urease test and UBT were all unaware of the results from the other diagnostic methods.

RESULTS

in the pre-treatment group (36 patients) the prevalence of H. pylori was 72%, the area under the ROC curve for the diagnosis of infection with the UBT was 0.99, and the best cut-off point was 5 units, with the following results: sensitivity= 96% (95% CI = 81-99%), specificity= 100% (69-100%), positive predictive value (PPV) = 100% (87-100%), negative predictive value (NPV) = 92% (59-100%), likelihood ratio (LR) + = infinity, and LR- = 0.04. In the post-treatment group (85 patients) the prevalence of H. pylori was 16%, the area under the ROC curve was 0.99, and the best cut point was 4.6, with the following results: sensitivity= 100% (77-100%), specificity = 97% (90-99%), PPV = 88% (62-98%), NPV = 100% (95-100%), LR+ = 35, and LR- = 0.

CONCLUSION

UBT provides excellent accuracy both for the initial diagnosis of H. pylori infection and to confirm eradication after treatment.

Multiple sclerosis in the tropics: genetic association to STR's loci spanning the HLA and TNF

Clear evidence has been presented correlating gene polymorphisms at 6p21.3-21.4 (containing HLA and TNF) and the predisposition to acquire multiple sclerosis (MS). In a previous study, we found that polymorphisms at HLA DQAI were associated with being or not being predisposed to MS in individuals inhabiting the tropics, where the prevalence of MS is significantly lower than in subtropical areas. Here, we tested the hypothesis that polymorphisms at D6S276, D6S265, D6S273 and D6S291 microsatellite loci are in strong linkage disequilibrium with a major genetic factor predisposing to MS. These microsatellites span the 6p21.3 region with intervals of 5 cM establishing particular landmarks for the HLA and TNF loci. Thirty-five MS patients and 35 controls, age, sex, social, ethnically and geographically matched healthy individuals, were studied. After testing the fit of gene frequencies to the normal distribution and performing the correlation for multiple comparisons, we found significant differences among the case and the control frequencies for the allele 202 belonging to the marker D6S276 (Pc=0.00455) and for the allele 114 belonging to the marker D6S265 (Pc=0.0084). For these two alleles at different loci, we found higher frequencies in the cases than in the controls. A nonsignificant p value was found in testing the existence of linkage disequilibrium among the studied loci in the cases and in the controls. In conclusion, the current study adds evidence to the established association among polymorphisms of genes located at 6p21.3-21.4 and MS. Furthermore, because of the distribution of the tested microsatellite loci, the more probable critical region could be correlated with the TNF neighborhood.

Chronic exposure of HepG2 cells to excess copper results in depletion of glutathione and induction of metallothionein

Metallothionein (MT) and reduced glutathione (GSH) play an important role in the intracellular handling of copper by preventing the generation and favouring the removal of copper-derived free radicals. The present study addressed the changes in MT and GSH that follow chronic (2 or 5 weeks) exposure of human hepatoblastoma cells (HepG2) to excess copper. Copper treatment (100 microM, 2 weeks) led to a 28-fold elevation in intracellular copper. Concomitantly, cells exhibited a seven-fold increase in total MT and an increment in its saturation with copper from 45 to 86%. Around 38% of copper in the cytosolic fraction could be accounted for by MT. GSH equivalents were substantially lowered (to 37% of basal levels) in treated cells, with only part of it being accounted for by an increase in GSSG. Copper-treatment induced no changes in catalase or GSH-peroxidase activities but it was associated with a small reduction in SOD (20%) and GSH-reductase (26%) activities. Copper-loaded cells did not differ from controls in their basal oxidative tone; however, when exposed to tert-butylhydroperoxide they exhibited a markedly greater susceptibility to undergo both oxidative stress and cell lysis. It is proposed that chronic exposure of HepG2 cells to excess copper is accompanied by "adaptive changes" in GSH and MT metabolism that would render cells substantially more susceptibility to undergo oxidative stress-related cytotoxicity.

Expression of lectin receptors on the membrane surface of sperm of fertile and subfertile boars by flow cytometry

Studies suggest that carbohydrates are important in different stages of fertilization. Plasma membrane changes accompanying in vitro capacitation and acrosome reaction (AR), such as removal or appearance of specific glycoproteins, have been studied using lectins that bind specifically to carbohydrate residues. In specialized artificial insemination farms and semen production centers, identification of boars with decreased fertilization ability (subfertility) is a newborn necessity. This investigation is a sequential study to determine the kinetics of surface carbohydrates turnover during in vitro capacitation and AR in fertile and subfertile boar sperm. Flow cytometry determinations of the binding of three FITC-labeled lectins were assessed. WGA binding was significantly lower in fresh, capacitated, and acrosome-reacted sperm of subfertile boars than in fertile boars. Con-A binding was not significantly different in fresh sperm of fertile and subfertile boars. However. Con-A labeling in capacitated, and acrosome-reacted sperm differed significantly in both groups. UEA binding increased only in capacitated sperm of subfertile boars. These findings could be used as indicators of capacitation and AR and may also be a good indicator of sperm fertilizing ability in boars.

Acrosome reaction in fertile and subfertile boar sperm

The main purpose of sperm evaluation is to predict its fertilizing ability. However, basic sperm test results show a low correlation with fertilizing ability. The purpose of this study was to determine whether there is an association between acrosome reaction (AR) and the incidence of subfertility of normal sperm boar. The production records of 22 farms were analyzed to identify boars with low fertility and/or prolificity, classified as subfertile. Twenty-two subfertile boar semen samples were analyzed and compared with 51 samples of fertile boars. Sperm were capacitated during 4 h at 39 degrees C. viability was determined by bisbenzimide (Hoechst-33258) staining. Acrosome reaction was assessed with fluorescein isothiocyanate conjugated Pisum sativum agglutinin. The percentage of spontaneous acrosome reaction (SAR) was not significantly different in fertile (4.5%) and subfertile boars (4.75%) (p > .05). Nevertheless, the percentage of progesterone-induced acrosome reaction (IAR) was significantly lower in subfertile boars (5.75%) as compared with fertile boars (10%) (p < .01). These results suggest that assessment of IAR in vitro may be a useful parameter to identify subfertility in boars.

Effect of perinatal food deficiencies on the compound action potential evoked in sensory nerves of developing rats

The aim of this study was to analyze the possible alterations produced by inadequate perinatal food intake, in quantity (undernutrition) or quality (malnutrition), on the generation and propagation of the compound action potential (CAP) evoked in sensory sural nerves, during the postnatal development of the rat. Low intensity stimulation (2-3 times the threshold of the most excitable nerve fibers; xT) of the sural nerve evoked an early potential (CAP-A component) which is due to activation of low-threshold, fast-conducting myelinated group A afferent fibers. Meanwhile, at higher stimulus intensity (20-30T) it produced a second, long-lasting potential (CAP-C component) probably due to activation of high-threshold, slow-conducting group Adelta or C afferent fibers. Compared to control nerves, the CAP-A component, but not the CAP-C component of undernourished and malnourished nerves showed significant changes in amplitude, area, electrical threshold and conduction velocity (except absolute refractory period) at several postnatal ages. Our results may suggest that a relative large number of myelinated group A afferent fibers in the sural nerve of undernourished and malnourished animals suffer severe alterations on their electrophysiological properties of generation and propagation of the action potential during the postnatal development of the rat.

Clinical features of multiple sclerosis in a genetically homogeneous tropical population

Individuals affected with multiple sclerosis (MS) from a genetically homogeneous Caucasian population in Antioquia, a tropical region of Colombia, were evaluated in order to observe the clinical behavior of the disease. The frequency of clinical manifestations in 65 patients with definite MS from Antioquia was compared with those reported from temperate regions. The most common manifestations were optic neuritis and motor symptoms with absence of cerebellar symptoms. This presentation is significantly different from the frequency distribution at onset in series from temperate regions. These differences suggest that environmental factors could modify the clinical expression of MS in this population.

[Internal jugular phlebectasia]

The jugular phlebectasia is an infrequent anomaly in which a jugular dilatations of the jugular vein during the Valsalva manoeuvre is the main characteristic. We report a case of a 7 years old male with an internal jugular phlebectasia manifestating as a latero-cervical right mass expanding with Valsalva manoeuvre. After the first initial echographic study, we recommend angio-TAC helicoidal as an useful test to confirm the diagnosis, it is also useful to get a tridimensional reconstruction of the jugular anomaly as well as establish the extension and possible complication. Jugular phlebectasia is a benign entity, usually it doesn't progress and causes a minimal estatic defect, therefore it is recommended to avoid any surgical resection or drapping. Periodical follow up is the best choice.

[Prevalence of multiple sclerosis in Colombia]

INTRODUCTION

Multiple sclerosis (MS) is the commonest demyelinating condition of the nervous system. It is characterized by numerous demyelinating areas or plaques of demyelination which are found dispersed throughout the nervous system. It has been shown that MS is less frequent in tropical regions than in subtropical regions. In Latin America particularly, there are some studies which show this phenomenon. However, in Colombia no studies of prevalence of MS have been done.

OBJECTIVE

To determine the prevalence of multiple sclerosis in five provinces of Colombia (Antioquia, Caldas, Santander, Risaralda and Bolivar).

PATIENTS AND METHODS

The capture-recapture method was used for two sources to determine the number of cases defined on the criteria of Poser et al seen between July 1995 and June 2000.

RESULTS

The prevalence (cases of MS per 100,000 inhabitants) varied between 1.48 in Antioquia (95% CI 1.12; 1.78) and 4.98 in Risaralda (95% CI 3.52; 6.43). Seventy two percent were women. The regions included in this study represented 25% of the population of Colombia.

CONCLUSIONS

There is a low prevalence of MS which is as expected in tropical areas. Persons with MS in these regions may be very useful in the study of other factors involved in the aetiology of MS (genetic). The capture-recapture method is an excellent tool for carrying out prevalence studies since it is cheap and requires little time.

Integrative medicine: a paradigm shift in medical education and practice

The use of alternative/complementary medicine has been increasing considerably. Conventional medicine must begin to address issues related to the use, safety, regulation, research and education of alternative/complementary medicine. Integrative medicine combines conventional medicine and alternative complementary practices. Integrative medicine is an innovative approach to medicine and medical education. It involves the understanding of the interaction of the mind, body and spirit and how to interpret this relationship in the dynamics of health and disease. Integrative medicine shifts the orientation of the medical practice from disease based approach to a healing based approach. It does not reject conventional medicine nor uncritically accepts unconventional practices. Integrative medicine is an effective, more fulfilling human approach to medicine based on the benefit of the patient by following good medicine practices in a scientific manner.

13C-urea breath test for the diagnosis of Helicobacter pylori infection: are basal samples necessary?

AIM

The 13C-urea breath test (13C-UBT) is one of the best methods for the diagnosis of Helicobacter pylori infection. Basal breath samples are usually obtained, in addition to those obtained after urea intake, as it has been suggested that basal values may oscillate among a population (e.g. depending on diet). However, the superiority of this strategy has not been sufficiently demonstrated. The elimination of basal samples in the 13C-UBT protocol would have the advantages of higher simplicity and speed.

METHODS

The 13C-UBT was performed in 714 consecutive patients. Mean age was 48 +/- 16 years, 49% were males, and in 48% of the patients previous H. pylori eradication therapy had been administered. Basal samples (13C-basal) and at 30 min after taking 100 mg of urea labelled with 13C (13C-post-urea) were obtained, delta over baseline (13C-DOB) being the algebraic difference between the ratio 13C/12C at these two points (which is the parameter usually given in studies, being considered positive when > 5%). A citric acid solution was used prior to urea intake.

RESULTS

The prevalence of H. pylori infection was 48%. Mean values of 13C-basal, 13C-post-urea, and 13C-DOB were, respectively, -19 +/- 2, 5.9 +/- 33, and 25 +/- 33. 13C-basal values oscillated between -25 and -14, being between -21 and -16 in 90% of the cases. Linear correlation coefficient for 13C-post-urea and 13C-DOB was 0.999 (determination coefficient, 0.998; P< 0.0001). The area under the receiver operating characteristic (ROC) curve for the diagnosis of infection when only 13C-post-urea was used (taking 13C-DOB >5% as the 'gold standard') was 0.997. Best results were obtained with 13C-post-urea cut-off point set at -13, with sensitivity of 97.4% (95% CI, 95-99%), specificity of 99.5% (98-100%), and positive likelihood ratio of 180. The concordance kappa value for both tests (13C-post-urea and 13C-DOB) using the aforementioned cut-off point was 0.97.

CONCLUSION

When performing the 13C-urea breath test it is sufficient to obtain samples 30 min after urea intake. Basal breath samples would not be necessary, which further simplifies this diagnostic method.

Eradication and follow-up of Helicobacter pylori infection in hemodialysis patients

It is currently accepted that Helicobacter pylori (Hp) infection is crucial in the pathogenesis of peptic ulcer. Therefore, we developed a prospective study to assess the prevalence of Hp infection by the 13C Urea Breath Test (13C UBT) in 52 hemodialysis patients, and we evaluated the efficacy of two consecutive eradication regimens in 23 positive patients with dyspepsia and/or on a transplantation list. The correlation between anti-Hp serology and 13C UBT results was also analyzed in 34 patients who were followed up during 18 months. The Hp prevalence by 13C UBT was 63.5% (33/52). The eradication rate after the first cycle of therapy (amoxicillin 500 mg/8 h and omeprazole 20 mg/12 h, 14 days) was 60.8% (14/23). After the second cycle (clarithromycin 500 mg/12 h plus omeprazole 20 mg/12 h, 14 days), the eradication rate reached 82.6% (19/23). The serological procedure showed a good correlation with 13C UBT (about 80% sensitive and specific) when very restrictive diagnostic and eradication criteria were adopted. We conclude that an eradication rate higher than 80% can be reached after two consecutive cycles of dual therapy in hemodialysis patients. Anti-Hp serological tests must be cautiously interpreted in these patients.

Effects of copper ions on the free radical-scavenging properties of reduced gluthathione: implications of a complex formation

The interaction between glutathione (GSH) and copper ions was investigated in vitro to determine whether such interaction could affect the free-radical scavenging properties of the tripeptide. To this end, the bleaching (decrease in OD734 nm) of a coloured solution containing the stable free-radical cation ABTS+, (which results from the addition of thiols to such a solution) was employed as an in vitro indication of the ability of the tripeptide to scavenge free radicals. While GSH bleached concentration-dependently (1.0-7.5 gM) the ABTS+-containing solution, its prior incubation (5 microM) in the presence of Cu+1 or Cu+2 ions (1-7.5 M) led to a metal concentration-dependent decrease of the bleaching capacity. At a ratio equal to one (5 microM each), the bleaching capacity of the copper plus GSH mixture was 50% of that seen for GSH alone. Further additions of copper (reaching ratios up to 2) did not result in greater decreases in the GSH-bleaching capacity. Noteworthy at the ratio of onewas that the copper plus GSH solutions maintained their bleaching capacity despite the lack of any DTNB-reactivity, i. e., the complete absence of thiols in the mixture. Mixtures of increasing concentrations of a fixed ratio (equal to 2) of copper plus GSH, which were found not to exhibit any DTNB-reactivity, showed a linear and concentration-dependent increase in bleaching capacity. The bleaching capacity remained unaltered when TRIEN, EDTA or histidine were added to pre-incubated (1:1) mixtures of copper plus GSH. However, the incubation of copper with TRIEN or EDTA (but not histidine) prior to GSH addition, totally prevented the loss of the original GSH-bleaching capacity. The present data supports the formation of a copper-glutathione complex which is stable to the presence of some copper-chelators, lacks all thiol reactivity, but fully conserves the free-radical scavenging properties of GSH.

Free-radical-induced inactivation of lysozyme and carbonyl residue generation in protein are not necessarily associated

The 2,2'-azobis(2-amidinopropane) (AAPH)-induced inactivation and oxidative modification of lysozyme, as determined by the loss of tryptophan-associated fluorescence (TAF) and the increase in dinitrophenylhydrazine-reactive carbonyl groups (CO), were studied in the absence and in the presence of antioxidants. AAPH induced a progressive inactivation of the enzyme and a parallel decrease of its TAF. Both changes were closely correlated (R2 = 0.97); however, the inactivation was only partially associated with an increase in CO. The latter reached maximal values at times half those needed to attain maximal losses in both lysozyme activity and TAF. A stoichiometric comparison reveals that whereas over 74% of the enzyme molecules had lost their activity, only 5% exhibited an increment in CO. CO formation was affected differentially by boldine and trolox. Both antioxidants fully protected against the early inactivation and loss of TAF; however, the increase in CO was completely unaffected by trolox. Exposure of lysozyme to Fe3+/ascorbate induced no loss of activity or TAF, but it led to an accumulation of CO similar to that induced by AAPH. Results indicate that CO formation and lysozyme inactivation are two mechanistically dissociable events and that changes in the former parameter can perfectly occur in the absence of changes in the latter.

Protective effects of boldine against free radical-induced erythrocyte lysis

Boldine, an aporphine alkaloid extracted from the leaves and bark of boldo (Peumus boldus Mol.), has been shown to exhibit strong free-radical scavenger and antioxidant properties. Here, we report the in vitro ability of boldine to protect intact red cells against the haemolytic damage induced by the free radical initiator 2, 2'-azobis-(2-amidinopropane) (AAPH). Boldine concentration-dependently prevented the AAPH-induced leakage of haemoglobin into the extracellular medium. Substantial and similar cyto-protective effects of boldine were observed whether the antioxidant was added 1 h prior to, or simultaneously with, the azo-compound. The delayed addition of boldine, by 1 h relative to AAPH, diminished but did not abolish its cytoprotective effect. However, negligible effects of boldine were observed after its addition to erythrocytes previously incubated with AAPH for 2 h. The data presented demonstrate that, in addition to its well-established antioxidant effects, boldine also displays time-dependently strong cytoprotective properties against chemically induced haemolytic damage.

Biological disposition of boldine: in vitro and in vivo studies

Boldine is a natural compound with well-established free radical scavenger and hepatoprotective properties. The further exploration of its actual therapeutic potential as an antioxidant is, however, partially limited by the absence of knowledge on its pharmacokinetics. In the present studies, we provide information on the in vitro and in vivo biological disposition of boldine. The addition of 200 microM boldine to an isolated rat hepatocyte suspension was followed by a time-dependent (0-60 min) disappearance of boldine from the extracellular medium. This decline was associated with an early (first 2 min) and swift accumulation (1600 microM) of boldine within the cells. Although the intracellular concentration of boldine diminished, boldine was always found to occur within the cells at concentrations substantially higher than those initially added to the preparation. Boldine was also concentration-dependently removed from the extracellular medium by isolated rat livers portally perfused with the antioxidant. In vivo studies, conducted in rats, revealed that following either its oral or its intravenous administration, plasma boldine concentrations declined rapidly and according to an apparently first order type of kinetics. After its oral administration (50 or 75 mg/kg), boldine was rapidly (within 30 min) absorbed and preferentially concentrated in the liver, with substantially lower concentrations being found in the brain and heart. Maximal hepatic concentrations of boldine were found to be equal to or greater than those needed to afford antioxidant and hepatoprotective effects in vitro.

[Molecular genetic aspects of the susceptibility to develop idiopathic epilepsy]

INTRODUCTION

There are more than 40 clinical types of epilepsy classified according to aetiology and/or mode of clinical onset. The term idiopathic epilepsy is reserved for cases with convulsions but no detectable structural lesions of the brain or neurological anomalies.

DEVELOPMENT AND CONCLUSIONS

In spite of many studies confirming the importance of genetic factors in the occurrence of idiopathic epilepsy, these appear to be complex and probably involve a locus of variable expression or several loci with similar phenotype expression (epistaxis). Also, environmental factors have variable effects. In recent years the principal genes involved in susceptibility to develop epilepsy have been mapped. In this way one mitochondrial and three autosomic genes have been cloned as responsible for the development of certain forms of this disorder. Also several studies of genetic linkage have given evidence, sometimes inconsistent, regarding the influence of another five loci in the susceptibility to develop epilepsy (6p21.2, 6q23-25, 8q24, 8p, 10q). On occasions the same locus has been linked with different forms of epilepsy, and on other occasions one form of epilepsy has been shown to be linked to several loci.

[Multiple sclerosis: epidemiological-genetic studies in the population of Antioquia, Colombia. Disequilibrium of HLA DQ alpha]

INTRODUCTION AND OBJECTIVE

Discrimination and quantification of the environmental and genetic components involved in developing multiple sclerosis (MS) have not been made. In order to discriminate these components we have ascertained affected individuals by MS belonging to the Paisa community from Antioquia, Colombia, a state localized in the tropical area of South America, to detect eventual linkage disequilibrium to HLA, locus DQ alpha, which could demonstrate the relevance of the genetic component.

DEVELOPMENT

A contingence analysis among case-control HLA DQ alpha genotype distributions, by using Monte Carlo resampling method to solve small number sample, showed that there are significant differences between the two groups. We observe that HLA DQ alpha 1.1, 1.2 allele frequencies were higher in the cases than in the controls. Also, there was significant HLA DQ alpha 3 allele lower frequency (p < 0.05) in the cases than in the controls.

CONCLUSIONS

Similar results have been described in other Caucasian populations living in non tropical areas. Before results could indicate that the Caucasoid populations genetic component implied in the susceptibility to MS have remained in Paisa community, whether the environmental component, being meaningful to develop MS.

[The recommendations of GESIDA/SEFH/PNS for improving adherence to antiretroviral treatment. AIDS Study Group of the Spanish Society of Hospital Pharmacy and the National Plan on AIDS of the Minister of Health and Consumers]

The main objective of HAART is to achieve a complete suppression of the viral replication for long time. However, when the therapeutic drug levels are low, HIV can replicate and it can develop resistances. This fact can be the reason of treatment failure, HIV transmission of resistant strains and therefore an inappropriate use of the economical resources. In order to get the adequate therapeutic drug levels it is necessary to have a good adherence to the treatment. We review the factors that influence the adherence, the evaluation methods and we recommend the possible intervention strategies which should be given by a multidisciplinary team, integrated by physicians, pharmacists, nurses, psychologists and other personal support. To start HAART is not an emergency. For this reason is very important to prepare to the patient and to identify the non-adherence factors in order to correct it. Once the HAART is indicated it is very important to offer information during the medical prescription and when the drugs are dispensed. During the therapy is necessary to follow actively all patients on HAART. In order to make therapeutical decisions we need to know the patient drug adherence rate. We recommend to use several methods to calculate the drug adherence rate, being the most commonly used the patient interview, the patient questionnaire, the refill count, the pharmacy visits rate together with the viral load evolution of the patient. In order to get all this information it is necessary to have a very good communication between all the people involved in HIV infected patients care. If non-adherence is detected it is necessary to start the intervention strategies to correct it and if they fail it might be necessary in some cases to stop HAART. The potential benefits of the adherence programs can justify the economical spend in human and hospital facilities resources.

[Genetic anticipation in idiopathic epilepsies]

INTRODUCTION

In extended and multigenerational pedigrees, the idiopathic epilepsy phenotype shows an extreme variability.

OBJECTIVE

The range of idiopathic epilepsy onset age in multigenerational pedigrees was studied in order to determine if genetic anticipation play a role in the heredity of Idiopathic Epilepsies.

PATIENTS AND METHODS

We compare the seizures onset age among relative-pairs of (parents-children, grandfathers-grandsons and nephew uncles). The mean onset age was compared using the Wilcoxon sign-rank paired-sample non-parametrical test to determine whether or not significant differences over > 0 exist, which refutes the null hypothesis of not anticipation. 84 pairs of relatives were taken from 72 extended multigenerational pedigrees.

RESULTS

The onset age of idiopathic epilepsy of the pairs showed a difference significantly > 0, which confirm the existence of intergenerational differences. This difference has a tendency to decrease in age which each successive generation. This difference occur in all relative pairs and therefore contradicts the ascertainment bias described by Penrose.

CONCLUSIONS

The results outline the existence of unstable mutations (those produced by a nucleotidic variable number of tandem repeats) as a probable explanation of the susceptibility to develop some forms of idiopathic epilepsy.

Multiple sclerosis: association to HLA DQalpha in a tropical population

Studies performed in subtropical populations have found significant association between the phenotype multiple sclerosis (MS) and the major histocompatibility complex (MHC). We present the results of a case-control study conducted on a tropical population (Antioquia, Colombia) in order to detect a possible association between MS and HLA DQalpha (HLA DQA1*) alleles. Forty chromosomes belonging to MS patients were compared to two sets of controls (40 and 910 chromosomes, respectively). The HLA DQA1*0101 and DQA1*0102 alleles were found in a significantly higher proportion among the cases than among the controls, whereas the HLA DQA1*0103 allele was found in a significantly lower proportion of the cases. These results suggest that the association of HLA DQA1*0101, DQA1*0102 and DQA1*0103 to the MS phenotype found in Caucasian subtropical populations remains in individuals with MS inhabiting the tropics. This finding could mean that the major genetic component associated to the MHC in subtropical populations is the same in the tropics.

[Surgery unit for epilepsy]

INTRODUCTION

Only few medically refractory epileptic patients are evaluated for surgical treatment, in spite of the good results obtained at the Centers where epilepsy surgery is performed.

OBJECTIVE

We are presenting the way the Gregorio Marañón Hospital Epilepsy Surgery Unit functions and their casuistry.

PATIENTS AND METHODS

This Unit is composed by members of the Services of Neurosurgery, Neurology, Neurophysiology, Neuroradiology, Psychology, Neuropediatry, Nuclear Medicine and Neuroanestesiology. Patients are studied by means of protocols.

RESULTS

Twenty cases were operated upon. The procedures were temporal lobectomy in 9 cases, amygdalo-hipocampectomy in 4, frontal lobectomy in 3, frontal topectomy in 2, partial hemispherectomy in 1 and vagal nerve stimulation in 1. In 16 of the 19 surgery specimen there were some pathological abnormalities. In the short follow-up 13 patients are seizures free experience significant improvement.

[Use of multidimensional scale for parents of children aged 6 to 11 for the diagnosis of attention deficit with hyperactivity]

INTRODUCTION

The BASC is a multidimensional approach to evaluate the child behavior and it has been validated on the diagnosis of ADD/+H in North American children.

OBJECTIVE

Validating BASC-PRS 6-11 on the diagnosis of ADD/+H.

PATIENTS AND METHODS

We selected 25 male DSM IV-ADD/+H (combined type), 6 to 11-years-old children, and 25 age, gender, and socioeconomic status matched controls. Mean ages of both groups 8.16 (1.5), schooling of controls 2.64 (1.4), and cases 2.6 (1.9).

RESULTS

On the Clinical Scale ADD/+H children had significant (Anova p < 0.01) higher scores in hyperactivity, conduct problems, and attention problems. On the Adaptive Scale only significant differences on social skills and leadership were found, with lower score in the ADD/+H group. A crosstab analysis between group code and each rating variable transformed into categorical (0 and 1) variable, cut-off point = 85 percentile, found that the case children's parents qualified as clinically in higher risk the variables attention problems (OR = 24.4; 95% CI = 4.5-130), conduct problems (OR = 9.0; 95% CI = 1.7-46.9) and hyperactivity (OR = 6.8; 95% CI = 1.6-28.5) (p < 0.01). A discriminant analysis selected attention problems as discriminant function (p < 0.0001). Classification capability 84% for each group.

CONCLUSION

Our results proved the validity of the BASC-PRS 6-11 questionnaire for the screening diagnosis of ADD/+H children in a Spanish speaking population.

[Mode of inheritance of idiopathic generalized non-myoclonic epilepsy in families investigated by studying members with idiopathic epilepsy with tonic-clonic crises on waking. Antioquia, Colombia]

In attempt to identify the possible role of mayor genes, multifactorial inheritance, and cohort effects in the susceptibility to idiopathic epilepsy with generalized tonic clonic seizures of the awakening type (GTCS), complex segregation analysis was performed in 196 nuclear families ascertained through affected with probands with idiopathic epilepsy with GTCS belonging to the Paisa community of Antioquia (Colombia). Models postulating no transmission, single mayor locus (dominant and recessive) only, and multifactorial component only, were rejected. The models postulating no polygenic component to transmission, and no transmission of the major effect were also rejected. Thus far, complex segregation analysis suggested that a major autosomal codominant allele together with a multifactorial component (mixed model) best explains clustering of idiopathic epilepsy with GTCS in families of the Paisa community. The deficit of transmission of heterozygotes (0.17) is compatible with the existence of epistasis acting on a major gene whose frequency was estimated to be 0.0211. Its transmission variance accounts for 81% of the susceptibility to idiopathic epilepsy with GTCS. The complementary variance (19%) is due to polygenic component.

[A system of multidimensional behavior assessment. A scale for parents of children from 6 to 11 years of age. Colombian version]

INTRODUCTION

Behavioral Assessment System for Children (BASC) has demonstrated to be useful in the diagnosis of Attention Deficit Disorder (ADD).

PATIENTS AND METHODS

A randomized sample of 120 children, 6 to 11-year-old, participants from the school of the city of Medellín, Colombia, was selected. The sample was stratified by sex and two socioeconomic status (SES). Parents were asked to answer the BASC Parent Rating Scale (PRS) 6-11, authorized Spanish version.

RESULTS

Cronbach's alpha coefficient was 0.85 for the clinical scale (9 items). It was 0.75 for the Adaptive Scale (3 items). A scale designed with 4 items to assess ADD (hyperactivity, attention problems, aggression, and conduct problems) showed an alpha coefficient of 0.82. Male children scored significantly higher than female (ANOVA, p < 0.05) in hyperactivity, conduct problems, and atypicality. Children from low SES scored significantly higher than children of high SES on the most of clinical measures (p < 0.05) and lower on the three adaptive measures. Cluster analysis selecting six clusters found a prevalence of 61.6% for normal male children. In the total sample there were a 4% at risk of DDA type II (inattentive) and 14% at risk of DDA type I (combined).

CONCLUSIONS

BASC PRS (6-11) showed reliability and validity to assessing the behavior in Spanish speaking Colombian children.

[Discrimination between genetic factors in attention deficit]

INTRODUCTION AND OBJECTIVE

In order to elucidate the genetic and environmental components involved in the susceptibility to develop attention deficit hyperactivity disorder (ADHD), a complex segregation analysis on nuclear families (n = 53) ascertained from affected probands belonging to Medellín, in the Antioquian State, Colombia, was performed.

METHODS AND RESULTS

Models of cohort effect (non-inheritance), multifactorial, recessive major gene, non-major gene component and non-transmission of major gene were rejected. Contrarily, dominant and codominant major gene models and non-multifactorial component could not be rejected. Thus, the better model fitting the data was that of the major gene (dominant/codominant). This major gene explains more than 99.99% of the ADHD phenotypic variance (value of heritability in the mixed model equal to 0.007%), which permit to assume a low aport of the environmental component to the phenotype ADHD. Gene frequency of the major gene was 3% in the general population of Antioquia and its penetrance was closed to 30%.

CONCLUSION

Some cautions and aspects related to the bias of the interview and diagnosis of the parents are discussed.

Neurocysticercosis in persons with epilepsy in Medellín, Colombia. The Neuroepidemiological Research Group of Antioquia

PURPOSE

A prospective series of 643 persons with epilepsy attending a reference neurologic center in Medellín, Colombia, was examined by computed tomography (CT scan) or serology or both with the enzyme-linked immunoelectrotransfer blot assay (EITB) to assess the prevalence of Taenia solium cysticercosis.

METHODS

All presenting patients were consecutively enrolled in the study. Five hundred forty-six persons underwent cerebral CT scans; 376 of them also had serum EITB performed.

RESULTS

Prevalence of neurocysticercosis by CT scan was 13.92%. Overall prevalence of T. solium antibodies with EITB was 9.82%, but for those with late-onset epilepsy (onset after age 30 years), prevalence increased to 17.5% and 19% for those who originated from outside urban Medellín. Seroprevalence in individuals with mixed lesions (cysts and calcifications) was 88.2% and 64.10% in those with live cysts. Conversely, only 2.72% of persons with CT findings not related to neurocysticercosis had positive EITB tests.

CONCLUSIONS

Our study shows that an important proportion of individuals with epilepsy have radiologic or serologic evidence of T. solium infection, suggesting that neurocysticercosis is an important etiology for epilepsy in Colombia.

Resistance in plants transformed with the P1 or P3 gene of tobacco vein mottling potyvirus

Tobacco plants were transformed with genes encoding the tobacco vein mottling potyvirus (TVMV) P1 or P3 protein. When compared with vector-transformed or P1 transgenic lines, seedlings of P3 transgenic lines (except a low expressor line) developed poorly, suggesting a detrimental effect of P3 on the plant. All P1 and P3 transgenic lines were protected against the homologous TVMV strain and showed variable proportions of two resistance phenotypes: asymptomatic plants or symptomatic plants that recovered from infection. The resistance was effective against a high inoculum dose but had a narrow spectrum. The heterologous strain TVMV-S was able to overcome resistance in most P1 lines but did not break the resistance of most P3 lines. No line showed resistance to another potyvirus (potato virus Y) or to potato virus X. These features and the low levels of transgene expression in resistant plants suggest that protection in P1 and P3 lines is RNA-mediated. In contrast with most reports on virus-activated gene silencing, some P3 lines with the predominant 'recovery' phenotype showed silencing of the transgene that was activated at a certain developmental stage of the plant independently of virus infection.

[Comparison of the multifactorial model as a hereditary mechanism of non-myoclonic generalized idiopathic epilepsy and partial idiopathic epilepsy]

OBJECTIVE AND METHODS

An experimental study about the predictions from the multifactorial threshold model created by Falconer is presented, assuming that this model may explain the genetic mechanisms underlying the family aggregation of idiopathic epilepsies.

RESULTS

We failed to confirm the following predictions from the falconer model: decreased prevalence of disease in relatives, proportional to decreased family links, and the order of birth effect. An heredity greater than 100% was calculated which is concordant with the presence of at least a locus with a major gen affect.

CONCLUSION

Our results reject the multifactorial threshold effect and suggest the presence of a major gen or Mendelian effect. An analysis of complex segregation is suggested for future studies.

[Therapeutic use of albumin: a discussion on its efficacy]

The aim of our study is to discuss the current recommendations for the use of intravenous albumin in hypoalbuminemic patients obtained from a literature review. Some data available lead us to the belief that its use does not influence the clinical outcome of the patients, in most of the cases in which it is employed. Therefore its use should be limited to a certain number of clinical situations, in which its efficiency has been clearly shown, as in new-born in whom plasma expansion with small volume is necessary, in cases in which synthetic colloids cannot be employed, in massive paracentesis in cirrhotic patients, in selected cases of edema unresponsive to diuretics or other colloids in plasmapheresis, in kidney and liver transplant surgery.

Sperm plasma membrane receptors for the porcine oocyte plasma membrane

In vitro fertilisation (IVF) was used to assess the ability of solubilised sperm plasma membrane (PM) proteins to inhibit the interaction of intact gametes. This is a first step before evaluating the ability of individual isolated proteins to competitively inhibit sperm-oocyte interaction as part of the process of studying the molecular events of fertilisation. Porcine oocytes were aspirated from ovaries, matured for 48 h in Medium 199, and the zona pellucida (ZP) was removed by exposure to acid Tyrode's solution. ZP-free matured oocytes were exposed to 200-800 micrograms/ml sperm PM protein for 1 h prior to insemination and during gamete co-incubation. Twenty-four hours after insemination with 5 x 10(5) capacitated sperm/ml, the oocytes were fixed, stained and examined. Sperm PM protein clearly inhibited IVF in a concentration-dependent manner (r = -0.87). The inhibition index (I50%), representing the sperm PM protein concentration necessary to inhibit IVF to 50% of the control value, was 310 micrograms/ml. These results demonstrate that solubilised sperm PM protein inhibits the interaction of intact gametes as one might expect for receptor-ligand interactions. Furthermore, the complement of sperm PM proteins appeared maximally effective at a calculated concentration of 690 microns/ml, providing a foundation for further studies with individual proteins.

[Antiochian genealogies in which idiopathic epilepsy presents familial conglomeration. Simulations of power for the detection of genetic linkage]

OBJECTIVE AND METHODS

We have analyzed a set of multigenerational extended pedigrees ascertained from affected cases of idiopathic epilepsy in the Antioquian Neurologic Institute. All pedigrees show familial aggregation of several forms of non myoclonic idiopathic epilepsy. In a recent paper, we have demonstrated that generalized idiopathic epilepsy of the awakening type is better explained by the existence of a major gene. In this paper, we have explored by simulation techniques the usefulness of the bigger pedigrees for linkage analysis. By using simlink and taking into account the parameters of the major gene, we have estimated that total power of three families is approximately 100 million times favoring the linkage detection.

RESULTS AND CONCLUSIONS

These analyses suggest that the major gene accounting by the susceptibility to develop generalized idiopathic epilepsy of the awakening type could be localized by typifying affected families belonging to the Paisa community from Antioquia, Colombia (Acta Neurol Colomb 1997; 13: 69-75).

Fixed drug eruption from amoxycillin

We present a case of fixed drug eruption on the genital mucosa induced by amoxycillin. Topical provocation was carried out, applying amoxycilin (10% pet) on the glans penis. No reaction was observed. Oral challenge with amoxycillin was followed by pruritic erythema on the glans penis 6 hours after the intake of 125 mg. The study of cross-reactivity to other betalactams showed good tolerance of phenoxymethyl-penicillin, which shares an identical nuclear structure with amoxycillin. The patient also tolerated cephadroxil, a cephalosporin with a side chain identical to that of amoxycillin. On reviewing the literature we have only found three reports of fixed drug eruption fue to amoxycillin.

[Prevalence of neurocysticercosis in individuals affected by epilepsy]

INTRODUCTION

In this investigations, was carried out a neurocysticercosis (NC) prevalence study during seven months in the Instituto Neurológico de Antioquia with the purpose of known neurocysticercosis frequency as cause of epilepsy in patients older than ten years that we attended in our institute.

MATERIAL AND METHODS

Computerized tomographies (CT) were made to 503 patients, with epilepsy, 24.7% of them were CT positive for NC. Cysticercosis enzyme linked immunoelectrotransfer blot (EITB) and enzyme linked immunoabsorbent assay (ELISA) test were made to 178 patients, 19.6% were EITB positive for NC and 5% ELISA positive for NC. Results. From this result it is possible to infer that about 8% of the 503 patients with epilepsy had cysticercosis, according to EITB that is the golden assay for NC. The CT and ELISA test had 94.3% and 27.7% sensitivity, respectively, according to EITB. The specificity of the CT for NC was 49.2% and specificity for ELISA test was 100% as compared to EITB. The multivariate analysis with logistic regression allowed to establish association of positive EITB with factors such as male sex, eating pork, headaches and multiple lesions in CT.

CONCLUSIONS

Prevention and education actions are necessary for the interruption of the neurocysticercosis transmission chain in order to diminish the high prevalence of epilepsy in the country and its complication and consequences.

[Epidemiology of cerebrovascular diseases in Sabaneta, Colombia (1992-1993)]

INTRODUCTION AND OBJECTIVES

In Columbia the epidemiology of cerebrovascular illness (ECV) is unknown. For this reason a study was made to determine the prevalence, incidence and annual mortality, and to identify the different types of ECV and the demographic characteristics of the population.

MATERIAL AND METHODS

In the urban area of Sabaneta, Columbia 13,588 door to door interviews were carried out among the inhabitants. A cutoff study carried out between April and June 1992 showed the prevalence of ECV. One year follow-up of persons without ECV between June 1992 and June 1993, enabled the incidence and annual mortality to be evaluated. A structured interview was used to identify the demographic characteristics of the population and classify people as healthy or as possibly having ECV. The latter were examined by neurologists to confirm or rule out the presence of ECV and to determine the type of ECV involved. Of the total urban population, 76.9% agreed to participate in the study. During the follow-up year, 8.4% were lost trace of.

RESULTS AND CONCLUSIONS

The prevalence of ECV was 559.3/ 100,000 inhabitants, increasing with age (15). In the 15-40 year old group, the incidence of ECV was 44 times higher in women than in men. The annual incidence rate was 88.9/100,000 inhabitants: thromboembolic disease was the most frequent. Of a total of 87 cases of ECV, 12 (13.98%) died of various causes during the year in which they were being observed. The annual mortality rate for ECV was 16.2/100,000 inhabitants, all being primary cases.

Loss of the metal binding properties of metallothionein induced by hydrogen peroxide and free radicals

The relationship between the metal-binding properties of metallothionein (MT) and its ability to interact with peroxides and free radicals was explored in vitro. The binding of 109Cd to MT and the thiol density of the protein were determined after incubation of a purified Zn/Cd-metallothionein preparation with either hydrogen peroxide alone, or with a number of free radical generating systems. Exposure of MT to H2O2, whether in the presence or absence of Fe2+, resulted in the progressive loss of the thiol residues of the protein and led to a parallel decrease of its 109Cd-binding capacity. These changes correlated with r values of 0.999 (P = 0.001) and 0.998 (P = 0.001), in the absence and presence of iron, respectively. The effects of H2O2, alone or plus Fe2+, on MT were completely prevented by catalase, but totally unaffected by superoxide dismutase or desferrioxamine. Exposure of MT to xanthine/xanthine oxidase also led to thiol oxidation and to a concomitant loss of the Cd-binding properties. In this system, both changes correlated with an r of 0.993 (P = 0.001) and were completely inhibited by superoxide dismutase. Exposure of MT to the peroxyl radical generator, 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH), resulted in the progressive loss of its the metal-binding properties and its thiol residues, both changes correlating with an r of 0.986 (P = 0.002). The ability of MT to bind 109Cd, lost as a result of its prior exposure to either H2O2 alone, H2O2 plus Fe2+, xanthine/xanthine oxidase, or to AAPH was, in all cases, completely recovered after incubation of the modified protein with dithiothreitol. These results indicate that H2O2 alone, and/or the oxygen-derived species, superoxide anion and peroxyl radicals, can all directly interact in vitro with MT to modify the protein oxidatively, and suggest that, under in vivo conditions, these species may be implicated as modifying factors of the metal-binding capacity of metallothionein.

In vitro fertilizing capacity of frozen-thawed boar semen

We describe a porcine semen cryopreservation technique and assess the in vitro fertilizing capacity of the frozen-thawed spermatozoa. The thawed spermatozoa did not lose the physiological properties of motility, viability, and acrosome reaction or capacity to fertilize in vitro. Immediately after thawing, the spermatozoa showed 51% mean motility, 60% viability, and 5% induced acrosome reaction. After 2.5 h of incubation in TALP medium, the spermatozoa exhibited 61% motility, 63% viability and 40% induced acrosome reaction. The average in vitro fertilization capacity of thawed spermatozoa was 68% compared with that of spermatozoa from fresh semen (85%). The percentage of polyspermy was highly variable, with frozen-thawed samples ranging from 0 to 28% and fresh samples from 0 to 30%. The results obtained with frozen semen from 5 boars of different breeds did not show considerable variation. This suggests that the freezing-thawing technique is reproducible and adequate for in vitro fertilization.

Group I extensor afferents evoke disynaptic EPSPs in cat hindlimb extensor motorneurones during fictive locomotion

1. Intracellular recording from extensor motoneurones in paralysed decerebrate cats was used to examine the distribution of short-latency non-monosynaptic excitation by group I afferents during fictive locomotion produced by stimulation of the mesencephalic locomotor region (MLR). 2. During the extension but not the flexion phase of fictive locomotion, stimulation of ankle extensor nerves at 1.2-2.0 times threshold evoked excitatory postsynaptic potentials (EPSPs) in motoneurones innervating hip, knee and ankle extensors. Disynaptic EPSPs were also evoked by selective activation of group Ia muscle spindle afferents by muscle stretch. 3. The central latencies of these group I-evoked EPSPs (mean, 1.55 ms) suggest their mediation by a disynaptic pathway with a single interneurone interposed between extensor group I afferents and extensor motoneurones. Disynaptic EPSPs were also evoked during periods of spontaneous locomotion following the cessation of MLR stimulation. 4. Hip extensor motoneurones received disynaptic EPSPs during extension following stimulation of both homonymous and ankle extensor nerves. Stimulation of hip extensor nerves did not evoke disynaptic EPSPs in ankle extensor motoneurones. 5. The appearance of disynaptic EPSPs during extension appears to result from cyclic disinhibition of an unidentified population of excitatory spinal interneurones and not postsynaptic voltage-dependent conductances in motoneurones or phasic presynaptic inhibition of group I afferents during flexion. 6. The reorganization of group I reflexes during fictive locomotion includes the appearance of disynaptic excitation of hip, knee and ankle extensor motoneurones. This excitatory reflex is one of the mechanisms by which group I afferents can enhance extensor activity and increase force production during stance.

Complex segregation analysis of non-myoclonic idiopathic generalized epilepsy in families ascertained from probands affected with idiopathic epilepsy with tonic-clonic seizures in Antioquia, Colombia

In an attempt to identify the possible role of major genes, multifactorial inheritance, and cohort effects in the susceptibility to idiopathic epilepsy with generalized tonic-clonic seizures of the awakening type (GTCS), complex segregation analysis was performed in 196 nuclear families ascertained through affected probands with idiopathic epilepsy with GTCS belonging to the Paisa community of Antioquia (Colombia). Models postulating no transmission, single major locus (dominant and recessive) only, and multifactorial component only, were rejected. Since the codominant single major locus model could not be rejected and models that assign no major locus to transmission, no polygenic component to transmission, and no transmission of the major effect were rejected, complex segregation analysis suggested that a major autosomal codominant allele together with a multifactorial component (mixed model) best explained clustering of idiopathic epilepsy with GTCS in families of the Paisa community. The deficit of transmission of heterozygotes (0.17) is compatible with the existence of epistasis acting on a major gene whose frequency was estimated to be 0.0211. Its transmission variance accounts for 81% of the susceptibility to idiopathic epilepsy with GTCS. The complementary variance (19%) is due to the polygenic component.

[Is there a correlation between the values of breath tests and the response to the treatment for the eradication of Helicobacter pylori?]

PURPOSE

To study a possible correlation between the urea breath test values prior to treatment and the response to Helicobacter pylori eradication therapy in patients with duodenal ulcer.

METHODS

Seventy-seven patients with duodenal ulcer were retrospectively studied (mean age: 46 +/- 13 years; 71% males). Initially, an endoscopy with biopsy samples (H&E stain) taken from antrum and body was performed, and a 13C-urea breath test (measuring 13C difference: delta 13CO2) was also performed. Both procedures were repeated one month after completing therapy ("classic" triple therapy [n = 25], and omeprazole plus amoxycillin [n = 52]).

RESULTS

Eradication was achieved in 40% of cases (n = 32), and it was higher in patients treated with "classic" triple therapy (60%) than in those treated with omeprazole plus amoxycillin (31%) (p = 0.017). Mean delta 13CO2 level was 25 +/- 15. There were no differences when comparing values of patients with successful eradication (24 +/- 18) or therapy failure (25.6 +/- 13). No differences were observed when considering both therapies separately or when comparing eradication rates depending upon breath test levels prior to therapy. Breath test values did not influence the eradication in the logistic regression model. Mean delta 13CO2 values after therapy in patients with eradication failure ran in parallel with those observed previously.

CONCLUSION

No correlation was observed between urea breath test values before treatment and the response to H. pylori eradication therapy in patients with duodenal ulcer. Thus, we conclude that quantification of this diagnostic method is not useful to predict the success or failure of eradicating therapy.

Effects of luteolin 5-O-beta-rutinoside in streptozotocin-induced diabetic rats

We have investigated the antidiabetic activity of luteolin 5-rutinoside in streptozotocin(STZ)-induced diabetic rats. Treatment for 20 days with 2 mg/kg increased both pancreatic insulin and DNA content. When both luteolin 5-rutinoside (2 mg/kg) and glibenclamide (1 mg/kg) were administered concurrently to STZ-diabetic rats, a marked antidiabetic activity was achieved. This effect was evidenced by a significant decrease in glycemia levels (> 50%), a 2.5-fold increase in insulin blood levels and an increase in body and pancreas weight, compared to the diabetic control group.

[Breath test in the diagnosis of Helicobacter pylori infection: concordance with histological methods and correlation with anatomopathological lesions of the gastric mucosa]

PURPOSE

To study the concordance between 13C-urea breath test and histology in the diagnosis of Helicobacter pylori infection, and to evaluate whether there is a correlation between breath test values and histologic lesions of the gastric mucosa.

METHODS

Sixty-nine patients with duodenal ulcer were prospectively studied. An endoscopy with biopsy samples (H&E stain) taken from the antrum and body was performed, and a 13C-urea breath test (measuring 13C difference: delta 13CO2) was also done. Both procedures were repeated one month after completing therapy ["classic" triple therapy (n = 28), and omeprazole+amoxycillin (n = 41)]. Eradication was defined as the absence of H. pylori both by histological and breath test methods.

RESULTS

At the beginning of the study, 94.2% of patients (n = 65) were H. pylori positive by histological methods, and 98.6% (n = 68) were positive by the breath test (ratio of positive agreement = 0.96). Kappa for H. pylori diagnosis after therapy was 0.83 (95% CI: 0.69-0.96). A correlation between delta 13CO2 and histologic lesions was observed, both in the antrum at before treatment (Spearman coef = 0.34; p = 0.007) and after therapy in both the gastric antrum (0.63; p < 0.001) and body (0.35; p = 0.005). A significant difference was observed when comparing mean delta 13CO2 in patients with different degrees of histologic gastritis, both before treatment (antrum: W Kruskal-Wallis = 6; p < 0.05) and after therapy (antrum: W = 17; p < 0.001; body: W = 10; p < 0.05).

CONCLUSION

A high concordance was observed between the 13C-urea breath test and histology in the diagnosis of H. pylori infection. A correlation exists between breath test values and histologic lesions of the gastric mucosa.

Betahistine-induced bronchospasm

Betahistine is a cerebral vasodilator structurally related to histamine, which stimulates H1 bronchial and vascular receptors. We report the case of a 28-year-old female patient who presented bronchospasm during treatment with betahistine hydrochloride. The prick test was negative. The oral challenge test showed bronchospasm and urticarial lesions. To the best of our knowledge, this is the first case of betahistine-induced bronchospasm reported in the literature. The study carried out failed to reveal the mechanism of the reaction.

Changes in PAD patterns of group I muscle afferents after a peripheral nerve crush

In the anesthetized cat we have analyzed the changes in primary afferent depolarization (PAD) evoked in single muscle spindle and tendon organ afferents at different times after their axons were crushed in the periphery and allowed to regenerate. Medial gastrocnemius (MG) afferents were depolarized by stimulation of group I fibers in the posterior biceps and semitendinosus nerve (PBSt), as soon as 2 weeks after crushing their axons in the periphery, in some cases before they could be activated by physiological stimulation of muscle receptors. Two to twelve weeks after crushing the MG nerve, stimulation of the PBSt produced PAD in all MG fibers reconnected with presumed muscle spindles and tendon organs. The mean amplitude of the PAD elicited in afferent fibers reconnected with muscle spindles was increased relative to values obtained from Ia fibers in intact (control) preparations, but remained essentially the same in fibers reconnected with tendon organs. Quite unexpectedly, we found that, between 2 and 12 weeks after crushing the MG nerve, stimulation of the bulbar reticular formation (RF) produced PAD in most afferent fibers reconnected with muscle spindle afferents. The mean amplitude of the PAD elicited in these fibers was significantly increased relative to the PAD elicited in muscle spindle afferents from intact preparations (from 0.08 +/- 0.4 to 0.47 +/- 0.34 mV). A substantial recovery was observed between 6 months and 2.5 years after the peripheral nerve injury. Stimulation of the sural (SU) nerve produced practically no PAD in muscle spindles from intact preparations, and this remained so in those afferents reconnected with muscle spindles impaled 2-12 weeks after the nerve crush. The mean amplitude of the PAD produced in afferent fibers reconnected with tendon organs by stimulation of the PBSt nerve and of the bulbar RF remained essentially the same as the PAD elicited in intact afferents. However, SU nerve stimulation produced a larger PAD in afferents reconnected with tendon organs 2-12 weeks after the nerve crush (mean PAD changed from 0.05 +/- 0.04 to 0.32 +/- 0.17 mV). The results obtained indicate that the PAD patterns of the afferent fibers reconnected with muscle spindle and tendon organ afferents are changed after crushing their axons in the periphery: stimulation of the bulbar RF appears to produce larger PAD in fibers reconnected with muscle spindles, and stimulation of cutaneous afferents produces larger PAD in fibers reconnected with tendon organs. It is suggested that these alterations in the patterns of PAD of muscle afferents result from central changes in the balance of excitatory and inhibitory influences acting on the segmental pathways mediating the PAD. Although the functional role of these changes has not been established, they may reflect compensatory changes aimed to adjust information arising from damaged afferents.