[Laparoscopic cholecystectomy in uremic patients]

The aim of this study was to evaluate the effectiveness of the laparoscopic cholecystectomy performed in two uremic patients with gallstones. From January to July 2004, 15 patients with gallstones underwent to laparoscopic cholecystectomy (LC). Two patients had chronic renal failure on haemodyalisis: a symptomatic fourty-two old woman, which had primitive hyperparathyroidism and primitive hyperaldosteronism, and asymptomatic transplant candidate fifty-five old man. No minor and major complications occurred and both patients were discharged 4 days after LC. Even in uremic patients the L. C. must be the gold standard for the treatment of gallstones both symptomatic and asymptomatic.

Taurine administration during lactation modifies hippocampal CA1 neurotransmission and behavioural programming in adult male mice

Taurine plays a role in neuronal development. In this study, we examined whether postnatal taurine administration influences the long-term consequences induced by mild neonatal stressors (10 min maternal deprivation plus sham injection, applied daily to neonatal mice up to 21 days). At 30 days of age stressed mice showed higher pain threshold both in the tail-flick--which measures mostly the spinal mechanisms of pain--and in the hot-plate test--which reflects mainly the supraspinal mechanisms of pain. The latter effect was prevented completely by neonatal taurine administration, while the tail-flick test was not affected, thus suggesting that spinal pain is not sensitive to taurine treatment. At 140 days of age, mice which were stressed during the neonatal period showed consistent decrease in immobility time in forced swimming test, and taurine did not influence this parameter. At the same age, the fear/anxiety axis, measured with elevated plus maze test, did not show any consistent changes. Electrophysiological experiments in brain slices obtained from adult mice showed that input-output curves in hippocampal CA1 were increased by taurine administration in lactation. Hence, neonatal administration of taurine might permanently modify the functioning of hippocampus, a brain area which is known to be crucial for learning and memory.

Effects of the synthetic cannabinoid nabilone on spatial learning and hippocampal neurotransmission

Cannabinoids, the active components of marijuana, affect memory and hippocampal neurotransmission. It has been claimed that nabilone, a synthetic cannabinoid endowed with antiemetic properties, has a peculiar profile of actions. We studied the effects of the drug on spatial learning and in vitro hippocampal CA1 electrophysiology in the rat. Nabilone (0.1, 0.5, and 1.0 mg/kg ip) does not impair place learning in a water maze task, whereas Delta(8)-tetrahydrocannabinol (Delta(8)-THC) disrupts this function. At concentrations ranging from 1 nM to 10 microM nabilone does not influence basal glutamatergic neurotransmission, which is decreased by Delta(8)-THC. Although cannabinoids have been consistently reported to affect synaptic plasticity, nabilone 1 microM does not change paired-pulse facilitation, long-term potentiation and the magnitude of long-term depression. However, the time course of the latter phenomenon is significantly changed by the drug, the depression being lower than in control experiments from 7 to 35 min postinduction. Altogether, our data indicate that there might be differences in the effects of agonists for central cannabinoid receptors, which could help to understand the pharmacology of this class of molecules. The results also suggest that amnesia induced by cannabinoids be possibly related to their effects on hippocampal neurotransmission. The study supports the use of nabilone in conditions the course of which is complicated by cognitive impairment.

[Methodological and regulatory features of clinical trials for behavioral and psychological symptoms in the course of dementia]

During the last few years there has been a growing awareness of behavioral and psychological symptoms of dementia (BPSD). These symptoms are usually classified in syndromes, which include psychosis, depression, agitation and sleep disturbances. BPSD have a major impact on the clinical course, prognosis and the quality of life of patients and caregivers. Moreover, BPSD considerably increase the social costs of dementia, since they often result in institutionalization. The therapy of BPSD was initially based on an empirical syndromic approach. However, in more recent years the efficacy and safety of treatments for these conditions have been tested in several controlled clinical trials. This paper addresses some of the methodological and regulatory issues that are relevant to the conducting of clinical trials for BPSD.

Effects of Win 55,212-2 on hippocampal CA1 long-term potentiation in experiments controlled for basal glutamatergic synaptic transmission

Cannabinoids, the active components of marijuana, are presumed to affect memory by an action on long-term potentiation. However, these molecules also reduce hippocampal glutamatergic neurotransmission. To distinguish the two activities, we studied the effects of the synthetic cannabinoid (R)-(+)-[2,3-Dihydro-5-methyl-3-(4-morpholinylmethyl)pyrrolo-[1,2,3-de]-1,4-benzoxazin-6-yl]-1-naphtalenylmethanone (Win 55,212-2, 10 microM) on CA1 hippocampal responses generated by the activation of two independent pathways, one of which was potentiated with a tetanic stimulation. The results of the study show the following: (a) the drug does not affect long-term potentiation provided that the responses are compared to those obtained in the unpotentiated control pathway; (b) Win 55,212-2 increases post-tetanic potentiation.

Does hypertension alone lead to cognitive decline in spontaneously hypertensive rats?

Spontaneously hypertensive rats (SHR) represent an animal model of cognitive decline associated with hypertension. Few studies have systematically investigated this decline in aging. We assessed spatial learning performances of SHR, the genetically similar Wistar-Kyoto rats (WKY), and Sprague-Dawley rats (SD), in a water maze (WM) task. The following age ranges were studied: 6, 12, and 20 months. The results demonstrated that all three strains show the same level of impairment at the age of 20 months. The rate of cognitive decline, however, is different: both SHR and WKY show moderate degrees of impairment at all age ranges, while SD display good cognitive abilities at 6 months, declining at 12, and reaching the performance level of the other two groups at 20 months. Besides, the nine groups showed substantial differences in swim velocity and WKY exhibited a peculiar motor behavior. These results suggest the following: (a) the decline in cognitive level exhibits different trends in the three strains; (b) learning impairment of aged SHR might not be entirely explained by hypertension; (c) WKY should be used cautiously as normotensive control for SHR, due to their unusual behavior and low learning abilities; (d) analysis of escape distances is mandatory for the comparison of different strains in the WM test.

Evolution of a single unit from general to geriatric surgery: a retrospective study comparing surgical management of elderly patients

The increase in the geriatric population in recent decades was not followed by a corresponding increase in attention on the part of surgeons to elderly patients until, in the '80s, many clinical studies showed that postoperative morbidity and mortality were related to the associated diseases rather than to the patients' age. To evaluate whether greater attention to the elderly is capable of increasing the number of operations that can be performed when necessary, we retrospectively surveyed the activity of a division of general surgery over two different periods of 5 years: the first one from 01/01/1985 to 31/12/1989 and the second from 01/01/1995 to 31/12/1999, when a team was specifically set up to take care of elderly patients. We registered a significant difference in the number of elderly patients operated on for tumours (134 vs. 208), an increase in colorectal neoplasms (24 vs. 70) and significant differences between radical and palliative surgery (P = 0.03). The extension of radical interventions for cancer to the elderly resulted in a moderate increase in postoperative complications. The surgery-related mortality was around 3.5% in both periods. Thus, a team of surgeons specifically dedicated to aged patients can improve the number of surgical operations performed in these subjects when required without any rise in postoperative mortality.

Corticotropin-releasing factor triggers neurite outgrowth of a catecholaminergic immortalized neuron via cAMP and MAP kinase signalling pathways

Corticotropin-releasing factor (CRF), a neuropeptide of 41 amino acids, acts as the major physiological regulator of the basal and stress-induced release of corticotropin (ACTH), beta-endorphin and other proopiomelanocortin-derived peptides from the anterior pituitary gland. In addition to its endocrine activity, CRF displays extrahypophysiotropic effects, mainly as a regulator of stress responses. We show here that CRF may additionally function as a differentiating factor in immortalized noradrenergic neuronal CATH.a cells that express CRF receptor type I and resemble locus coeruleus-derived neurons. CRF triggers morphological changes in CATH.a cells including the appearance of extended long, slender neurites with prominent growth cones. CRF-treated CATH.a cells exhibit a morphology similar to locus coeruleus neurons in primary culture. CRF-induced neurite outgrowth of CATH.a cells was blocked by addition of inhibitors for cAMP-dependent protein kinase or extracellular signal-regulated protein kinase (ERK), a subtype of the mitogen-activated protein kinases. The participation of ERK within the CRF signalling cascade was further confirmed by Western blot experiments, with antibodies directed against the phosphorylated form of ERK, and also with transcription-based assays. We conclude that CRF functions as a differentiating factor of CATH.a cells via the cAMP and the MAP kinase signalling pathways.

Failure of detection of the tyrosine to histidine substitution at the residue 33 of thymidylate synthase in human colorectal cancer. A preliminary study

Structural changes in the macromolecular targets of pharmacological agents can result in alterations in the efficacy of these agents. In previous studies Berger et al. (1) identified a variant structural form of thymidylate synthase (TS) that is associated with relative resistance to 5-fluoro-2'-deoxyuridine, in a human colonic tumor cell line. They observed that expression of the variant TS, which differs from the normal form by a tyrosine to histidine substitution at residue 33, confers a 4-fold level of drug resistance in mammalian cells, as well as in bacteria. Now we report on the use of RT-PCR techniques to see if that variant TS form could be present in human samples from patients who underwent surgery for primary colorectal cancer and been previously untreated and to try to find relationships between that hypothetical variant TS form and the 5-Fluorouracil treatment. The possible role of Tyr-33 in 5-fluoropyrimidine-mediated inhibition of TS is discussed.

[Activity of purified diosmin in the treatment of hemorrhoids]

Several theories on the etio-pathogenesis and physio-pathology of hemorrhoids have been up to now proposed. From the fisio-pathological viewpoint, particular importance is retained by the vascular factor, which in its turn is influenced by mechanical and sphinceric factors, that impair the venous back-flow. In the evidence of an hemorrhoidal crisis, characterized by local oedema, pain and bleeding, the use of bioflavonoid drugs is deemed to be the first choice. We investigated the use of purified diosmin, given at a dose of two 450 mg tablets bid for the first 7 days, then at 1 tablet bid for up to 2 months, in a group of 66 patients suffering from primitive hemorrhoids of grade 1-4. Our results confirmed diosmin efficacy in decreasing both pain and bleeding: reduction rates of 79% and 67%, respectively, were reached in the first treatment week. In the second week, figures were 98% and 86%, respectively. Diosmin tolerability was excellent: this characteristic makes the drug very easy to handle by the general practitioner and also useful to the proctologist in the preparation of patient to further treatments.

Prevention by L-alpha-phosphatidylcholine of antifungal activity in vitro of liposome-encapsulated imidazoles determined by using time-killing curves

The antifungal activity of the imidazole derivatives miconazole and ketoconazole was reduced when they were entrapped in liposomal structures and significant differences were detected between small unilamellar vesicles (SUV) and multilamellar vesicles (MLV). To understand which component of liposomes interfered with the antifungal activity of miconazole and ketoconazole, we examined the influence of pure egg and soy L-alpha-phosphatidylcholine and cholesterol on activity against Candida albicans ATCC E10231 by time killing curves. Association of phospholipids-cholesterol-imidazole leads to an inhibitory effect on the antifungal activity comparable to that shown when miconazole or ketoconazole were entrapped in SUV liposomes or when miconazole and ketoconazole were incubated in the presence of L-alpha-phosphatidylcholine. The antifungal activity determined in the presence of cholesterol was comparable to that observed with the free drugs. Inhibition of the antifungal activity of miconazole and ketoconazole by phospholipids is dependent on the phospholipid concentration but is independent of the source of phospholipids (egg or soy). Cholesterol had no influence on the antifungal activity of the imidazoles, unlike the effect on other antifungal drugs, such as amphotericin B.

Resveratrol, a natural stilbene in grapes and wine, enhances intraphagocytosis in human promonocytes: a co-factor in antiinflammatory and anticancer chemopreventive activity

Trans-resveratrol, a natural stilbene present in wine and grapes, has been studied mainly for its antiinflammatory and anticancer activities. In this study the activity of resveratrol on proliferative immunological parameters (differentiation, apoptosis, phagocytosis and intracellular killing) was studied using a U937 human promonocytic cell line in comparison with another polyphenol, quercetin. After incubation of the pathogen, Candida albicans, intracellular killing by macrophage-like cells was decreased by quercetin and resveratrol 10 microM but was enhanced by resveratrol 1 microM after 20 h of treatment. Phagocytosis rate, expressed as phagocytosis frequency, (i.e., percentage number of phagocytosing cells/total cells) at 20 h was highest with resveratrol 10 microM and was higher with quercetin 10 microM than with resveratrol 1 microM. The phagocytosis index exhibited the same trend. While both polyphenols demonstrated cytostatic activity on U937 growth, a prointraphagocytic effect for resveratrol 10 microM-treated cells at 10 min, resveratrol 1 microM-treated cells at 20 h and resveratrol 10 microM-treated cells at 48 h was observed. Morphological examination with optic microscopy demonstrated both apoptotic and differentiating cells, even after 10 min treatment. Resveratrol-induced apoptosis (following 4 h treatment) was confirmed by flow cytometry at concentrations as low as 1 microM and 100 nM in the assay for detection of membrane phosphatidylserine. Resveratrol- or quercetin-treated, but unstimulated cells, did not produce tumor necrosis factor-alpha protein. As phosphatidylserine externalization triggers specific recognition by monocytes and macrophages, removal of intact apoptotic cells is important a) in cell population selection and differentiation for antiblastic therapy, and b) in preventing the release of toxic inflammatory substances such as reactive oxygen substances and proteolytic enzymes by dying cells. This observation suggests that wine polyphenols, at the same concentrations as those found in plasma after moderate wine consumption, are important cofactors in antiinfective, antiinflammatory and anticancer nonspecific immune reactions.

The role of thymidylate synthase levels in the prognosis and the treatment of patients with colorectal cancer

Inhibition of Thymidylate Synthase (TS) by the 5-Fluorouracil (5Fu) active metabolite Fluoro-deoxy-uridine-monophosphate (FdUMP) is considered to be the main mechanism of action of 5Fu. TS level from tumors and normal mucosa of 62 untreated patients who underwent surgery for primary colorectal adenocarcinoma was performed. The aim of this study was to evaluate the possibility of considering the TS level as a prognostic factor of the disease. A large variation in the level of the enzyme was found among tumors. Our data demonstrate that there is no association with age, sex, and tumor size; however there are significant relationships between TS levels and staging and histological grading. In fact the TS values are higher in Dukes' A and in G1 than in Dukes' D and G3 tumors (p < 0.05). Another significant association has been found between the TS level and tumor site: pts with right colon neoplasias had higher TS levels than pts with left and rectum ones. An interesting trend was found between the TS levels and survival parameters. Pts who had lower TS levels had a significantly increased risk of death (p < 0.05) over pts with a higher outcome. Our data support the hypothesis that a high TS level is a favourable prognostic factor in human untreated colorectal carcinomas according to our previous preliminary data (1).

[The prognosis of surgery on the elderly. Proposal for a parametric evaluation]

BACKGROUND AND AIMS

To data there are no preoperative systems of evaluating surgical risk specifically in geriatric patients. Given that it was thought useful to formulate a score-based prognostic system for these patients based on surgical risk, the authors collected a wide range of preoperative data with the aim of identifying the easily determined variables.

METHODS

While data from other hospital centres are in the process of being collected, the authors report the data for 122 over 65-year-old patients who underwent elective surgery up until 30-1-1996 out of a total of 329 hospitalized patients. In addition to a wide series of objective, laboratory and instrumental data, the study also took into account the pathology requiring to surgery, any associated morbid conditions, psychic and social conditions, the type of surgery and local and/or general postoperative complications.

RESULTS

Hernia of the abdominal wall were found to be the most frequent cause of surgery (41 cases), followed by 27 neoplasias of various organs and biliary lithiasis (20 cases). Cardiovascular diseases were the most common associated pathologies (85 patients). A total of 13 major and 80 medium operations were performed, including 16 cholecystectomies. Among the general complications, an altered acid-base balance was found in 7 patients. Two deaths were recorded within 30 days of surgery. When the data collection is complete, the results will be analysed statistically in order to obtain a numerical calculation of the coefficients of risk correlated to the individual variables.

CONCLUSIONS

This will enable the criteria of operability to be broadened, thereby allowing surgery to be performed in those patients who are currently excluded merely on the basis of the personal judgement of the surgeon and anesthetist.

Ultrastructural synaptic correlates of spatial learning in rat hippocampus

Memory formation is believed to alter neural circuitry at the synaptic level. Although the hippocampus is known to play an important role in spatial learning, no experimental data exist on the synaptic correlates of this process at the ultrastructural level. Here, we have employed quantitative electron microscopy in order to compare the density, size and spatial arrangement of synapses in the dentate gyrus, and in area CA1, of spatially trained (water maze, invisible platform) versus control (visible platform) rats. No training-associated changes of hippocampal volume were found using a stereological estimaion (disector) of the volume density of dentate granule, or CA1 pyramidal cells. Nor were changes found in either density, or sizes of synapses (spinous or dendritic), in CA1 or dentate gyrus. However, analysis of synaptic spatial distribution showed a training-associated increase in the frequency of shorter distances (i.e. clustering) between synaptic active zones in CA1, but not dentate, thus indicating alterations in local neural circuitry. This finding indicates subtle changes in synaptic organization in area CA1 of the hippocampus following a learning experience, suggesting that spatial memory formation in mammalian hippocampus may involve topographical changes in local circuitry without synapse formation de novo.

Clinical and anatomic features of the inguinal canal during hernia

Seventy-eight patients affected by inguinal hernia, 33 by direct and 45 by indirect external oblique types, were studied. The morphologic and structural aspects of the inguinal canal including its length, the diameter of the deep inguinal ring and the qualitative features of the fascia transversalis and aponeuroses of the external and internal oblique muscles and of the transversus muscle were investigated. In all 78 patients with inguinal hernia, the length of the canal was 4.7 cm. In the 33 patients with direct inguinal hernia the width of the deep inguinal ring varied from 1.5 to 2.5. The aponeurosis of the external oblique muscle was dense in 19 cases (57.58%), rather laddered in 10 (30.30%) and very laddered in 4 (12.12%). The fascia transversalis was discontinued in 28 cases (84.85%) and velamentous in 5 cases (15.15%). In the 45 patients with indirect inguinal hernia the width of the deep inguinal ring varied from 1.5 to 7 cm. The aponeurosis of the external oblique muscle was dense in 14 cases (31.11%), rather laddered in 23 cases (51.11%), very laddered in 8 (17.78%). The fascia transversalis was dense in 15 (33.33%), elastic in 17 (37.78%) and velamentous in 13 cases (28.89%). Based on the results of this study, a series of therapeutic considerations are set forth. The most important of these include early surgical intervention, which is absolutely necessary, and the use of prostheses in the inguinal canal.

Cryoglobulinemia in transfusion-dependent thalassemia major

OBJECTIVE

The aim of this study was to determine the frequency of cryoglobulinemia and associated symptoms in transfusion-dependent thalassemia patients at high risk for HCV infection.

METHODS

A controlled epidemiological study was used to evaluate the prevalence of clinical, biochemical and immunological abnormalities in a group of 264 HCV-positive and 106 HCV-negative transfusion-dependent thalassemia patients. Haematologic and hepatic function tests were performed according to standard methods. HCV-RNA was detected by PCR analysis.

RESULTS

The significant presence of cryoglobulinemia and associated symptoms (purpura, vasculitis, arthritis, asthenia, proteinuria), serum autoantibodies (SMA, anti-GOR, ANA, LKM), low complement and rheumatoid factor were found in HCV-positive compared with HCV-negative patients.

CONCLUSIONS

This study demonstrates the role of HCV in inducing cryoglobulinemia and immunological disorders in transfusion-dependent thalassemia patients. HCV infection and associated immune abnormalities are a new clinical aspect of, and deserve particular attention due to their high frequency in, transfusion-dependent thalassemia patients.

Anticholinergic antiparkinsonian therapy in outpatients treated with neuroleptic drugs: a prescription survey

Extrapyramidal adverse effects (EPAs) due to neuroleptic treatment are routinely treated with anti-cholinergic antiparkinsonian drugs (APDs). We studied the use of these drugs in the general population exposed to neuroleptic drugs to improve our knowledge of the epidemiology of EPAs. We selected all the neuroleptic and antiparkinsonian drug prescriptions delivered in the province of Rome (ca. 3,750,000 inhabitants) from 1986 to 1989. During the study period, 10.6% of neuroleptic-treated subjects were concurrently prescribed anticholinergic antiparkinsonian drugs. The influence of different factors on APD prescriptions was evaluated through a logistic regression model. The highest probability of receiving APDs was associated with trifluperidol treatment (odds ratio = 5.0, using chlorpromazine as baseline); among the commonly prescribed neuroleptics, sulpiride, levosulpiride and tiapride chlorydrate had the lowest probability of coprescription with APDs (odds ratios less than 0.1). The probability of being prescribed anticholinergic antiparkinsonian drugs decreased with age and increased with the amount of neuroleptics prescribed. This study surveys a very large sample using a population-based approach, whereas the same topics have previously only been studied in limited inpatient populations.

Reduced hippocampal CA1 Ca(2+)-induced long-term potentiation is associated with age-dependent impairment of spatial learning

Expression of Ca(2+)-induced CA1 long-term potentiation (LTP) was analysed in hippocampal slices obtained from (1) 3-month-old and (2) 18-20-month-old Sprague-Dawley rats selected for their performances in the Morris water maze task. In all slices, a transient (10 min) increase of extracellular Ca2+ concentration (4 mM) caused a long-lasting enhancement of potentials evoked by electrical stimulation of radiatum fibers. However, a significant difference was found in the degree of potentiation among groups. In particular, increases of the CA1 response amplitudes were significantly lower in old rats impaired in spatial learning than in young at 30 (P < 0.05), 60, 90 and 120 min (P < 0.01) after restoring the normal Ca2+ concentration. On the contrary, no differences were observed between young animals and the old ones with good performances in spatial learning. The data suggest that amplitude of CA1 Ca(2+)-induced LTP in old rats is related to spatial learning abilities.

The structure of coxsackievirus B3 at 3.5 A resolution

BACKGROUND

Group B coxsackieviruses (CVBs) are etiologic agents of a number of human diseases that range in severity from asymptomatic to lethal infections. They are small, single-stranded RNA icosahedral viruses that belong to the enterovirus genus of the picornavirus family. Structural studies were initiated in light of the information available on the cellular receptors for this virus and to assist in the design of antiviral capsid-binding compounds for the CVBs.

RESULTS

The structure of coxsackievirus B3 (CVB3) has been solved to a resolution of 3.5 A. The beta-sandwich structure of the viral capsid proteins VP1, VP2 and VP3 is conserved between CVB3 and other picornaviruses. Structural differences between CVB3 and other enteroviruses and rhinoviruses are located primarily on the viral surface. The hydrophobic pocket of the VP1 beta-sandwich is occupied by a pocket factor, modeled as a C16 fatty acid. An additional study has shown that the pocket factor can be displaced by an antiviral compound. Myristate was observed covalently linked to the N terminus of VP4. Density consistent with the presence of ions was observed on the icosahedral threefold and fivefold axes.

CONCLUSIONS

The canyon and twofold depression, major surface depressions, are predicted to be the primary and secondary receptor-binding sites on CVB3, respectively. Neutralizing immunogenic sites are predicted to lie on the extreme surfaces of the capsid at sites that lack amino acid sequence conservation among the CVBs. The ions located on the icosahedral threefold and fivefold axes together with the pocket factor may contribute to the pH stability of the coxsackieviruses.

Estimate of parkinsonism prevalence through drug prescription histories in the Province of Rome, Italy

INTRODUCTION

The objective of the study was to estimate the prevalence of parkinsonism in the Province of Rome using antiparkinsonian prescription histories from 1986 to 1991.

METHODS

A subject was defined as a case of parkinsonism if he/she had received "specific" and "consistent" antiparkinsonian therapy in the study period.

RESULTS

In November 1990, 6,572 patients were defined as prevalent cases of parkinsonism. The crude prevalence ratio, for the total population of the Province of Rome, is 173.5 per 100,000 inhabitants (165.9 per 100,000 in men and 180.5 per 100,000 in women). The method was validated by record-linkage with clinical records of all patients visited during 1990 at the Department of Neurological Sciences of the University of Rome "La Sapienza". The sensitivity of the prevalence study was 83.6%.

CONCLUSIONS

The use of a computerized data base of all prescription data, routinely collected for administrative purposes, enabled us to obtain a prevalence estimate based on a very large population, with low costs and in a relatively short time.

Selective reduction of hippocampal dentate frequency-potentiation in striatally lesioned rats with impaired place learning

The induction of hippocampal frequency-potentiation (i.e. post-tetanic potentiation (PTP) and long-term potentiation (LTP) was analyzed in rat hippocampal slices obtained from animals showing impaired place learning in the Morris water maze as a consequence of bilateral striatal injection of quinolinic acid. Vehicle-injected animals, showing normal performances in the Morris water maze, behaved as controls. After the application of an electrical tetanus (1 s, 100 Hz, 50 microA) in the stratum radiatum, no significant differences were found in the percent of induction of both PTP and LTP in the CA1 area of hippocampal slices obtained from lesioned and sham-operated rats. After the application of an electrical tetanus (1 s, 100 Hz 50 microA) in the stratum moleculare, a significant difference was found in the percent of dentate PTP induction in hippocampal slices obtained from lesioned and sham-operated rats. Specifically, dentate PTP induction was significantly (P < 0.01) higher in slices obtained from sham-operated rats with a good performance in the Morris water maze than in slices obtained from striatally lesioned rats, which had shown poor performance in the Morris water maze. On the contrary, no significant differences were found in the percent of dentate LTP in hippocampal slices obtained from rats of the two groups. The data demonstrate that the impairment of the place learning in striatally lesioned rats is associated with a selective reduction of hippocampal dentate frequency-potentiation.

Effect of iron overload on the response to recombinant interferon-alfa treatment in transfusion-dependent patients with thalassemia major and chronic hepatitis C

The purpose of this study was to determine whether interferon-alfa (IFN-alpha) therapy benefits patients with transfusion-dependent thalassemia and chronic active hepatitis C, and whether their iron burden modifies the response to this therapy. We conducted a controlled trial of recombinant IFN-alpha (3 million units per square meter of body surface area, three times a week for 15 months) in 65 patients with thalassaemia major and chronic active hepatitis C; 14 of them were untreated control subjects. In 21 of the 51 treated patients, alanine aminotransferase values returned to normal within 6 months, and hepatitis C virus ribonucleic acid was no longer detected in serum; no changes were detected among control subjects. The response to IFN-alpha therapy was inversely related (p < 0.002) to the liver iron burden as assessed by atomic absorption, the histologic semiquantitative method, or both methods. During 3 years of follow-up, two responder patients had relapses. We conclude that IFN-alpha represents a useful therapeutic option for children with transfusion-dependent thalassemia and chronic active hepatitis C with a mild to moderate iron burden.