Aberrant use and poor quality of trypanocides: a risk for drug resistance in south western Ethiopia.

BACKGROUND: Trypanocidal drugs have been used to control African animal trypanosomosis for several decades. In Ethiopia, these drugs are available from both authorized (legal) and unauthorized (illegal) sources but documentation on utilization practices and quality of circulating products is scanty. This study looked at the practices of trypanocidal drug utilization by farmers and the integrity of active ingredient in trypanocides sold in Gurage zone, south western Ethiopia. The surveys were based on a structured questionnaire and drug quality determination of commonly used brands originating from European and Asian companies and sold at both authorized and unauthorized markets. One hundred farmers were interviewed and 50 drug samples were collected in 2013 (Diminazene aceturate = 33 and Isometamidium chloride = 17; 25 from authorized and 25 from unauthorized sources). Samples were tested at the OIE-certified Veterinary Drug Control Laboratory (LACOMEV) in Dakar, Senegal, by using galenic standards and high performance liquid chromatography. RESULTS: Trypanosomosis was found to be a major threat according to all interviewed livestock keepers in the study area. Diminazene aceturate and isometamidium chloride were preferred by 79% and 21% of the respondents respectively, and 85% of them indicated that an animal receives more than six treatments per year. About 60% of these treatments were reported to be administered by untrained farmers. Trypanocidal drug sources included both unauthorized outlets (56%) and authorized government and private sources (44%). A wide availability and usage of substandard quality drugs was revealed. Twenty eight percent of trypanocidal drugs tested failed to comply with quality requirements. There was no significant difference in the frequency of non-compliance between diminazene-based and isometamidium chloride products (P = 0.87) irrespective of the marketing channel (official and unofficial). However, higher rates of non-compliant trypanocides were detected for drugs originating from Asia than from Europe (P = 0.029). CONCLUSION: The findings revealed the presence of risk factors for the development of drug resistance, i.e. wide distribution of poor quality drugs as well as substandard administration practices. Therefore, it is strongly recommended to enforce regulatory measures for quality control of veterinary drugs, to expand and strengthen veterinary services and to undertake trypanocidal drug efficacy studies of wider coverage.

The consolidation of inhibitory avoidance memory in mice depends on the intensity of the aversive stimulus: The involvement of the amygdala, dorsal hippocampus and medial prefrontal cortex.

Several studies using inhibitory avoidance models have demonstrated the importance of limbic structures, such as the amygdala, dorsal hippocampus and medial prefrontal cortex, in the consolidation of emotional memory. However, we aimed to investigate the role of the amygdala (AMG), dorsal hippocampus (DH) and medial prefrontal cortex (mPFC) of mice in the consolidation of step-down inhibitory avoidance and whether this avoidance would be conditioned relative to the intensity of the aversive stimulus. To test this, we bilaterally infused anisomycin (ANI-40µg/µl, a protein synthesis inhibitor) into one of these three brain areas in mice. These mice were then exposed to one of two different intensities (moderate: 0.5mA or intense: 1.5mA) in a step-down inhibitory avoidance task. We found that consolidation of both of the aversive experiences was mPFC dependent, while the AMG and DH were only required for the consolidation of the intense experience. We suggest that in moderately aversive situations, which do not represent a severe physical risk to the individual, the consolidation of aversive experiences does not depend on protein synthesis in the AMG or the DH, but only the mPFC. However, for intense aversive stimuli all three of these limbic structures are essential for the consolidation of the experience.

Animal trypanosomosis: making quality control of trypanocidal drugs possible.

African animal trypanosomosis is arguably the most important animal disease impairing livestock agricultural development in sub-Saharan Africa. In addition to vector control, the use oftrypanocidal drugs is important in controlling the impact of the disease on animal health and production in most sub-Saharan countries. However, there are no internationally agreed standards (pharmacopoeia-type monographs or documented product specifications) for the quality control of these compounds. This means that it is impossible to establish independent quality control and quality assurance standards for these agents. An international alliance between the Food and Agriculture Organization of the United Nations, the International Federation for Animal Health, the Global Alliance for Livestock Veterinary Medicines, the University of Strathclyde and the International Atomic Energy Agency (with critical support from the World Organisation for Animal Health) was established to develop quality control and quality assurance standards for trypanocidal drugs, with the aim of transferring these methodologies to two control laboratories in sub-Saharan Africa that will serve as reference institutions for their respective regions. The work of the international alliance will allow development of control measures against sub-standard or counterfeit trypanocidal drugs for treatment of trypanosome infection. Monographs on diminazene aceturate (synonym: diminazene diaceturate), isometamidium chloride hydrochloride, homidium chloride and bromide salts and their relevant veterinary formulations for these agents are given in the annex to this paper. However, the authors do not recommend use of homidium bromide and chloride, because of their proven mutagenic properties in some animal test models and their suspected carcinogenic properties.

Two SERK genes are markers of pluripotency in Cyclamen persicum Mill.

The genetic basis of stem cell specification in somatic embryogenesis and organogenesis is still obscure. SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE (SERK) genes are involved in embryogenesis and organogenesis in numerous species. In vitro culture of Cyclamen persicum immature ovules provides a system for investigating stem cell formation and maintenance, because lines forming either organs or embryos or callus without organs/embryos are available for the same cultivar and plant growth regulator conditions. The present aim was to exploit this property of cyclamen cultures to understand the role of SERK(s) in stem cell formation and maintenance in somatic embryogenesis and organogenesis in vitro, in comparison with expression in planta. CpSERK1 and CpSERK2 were isolated from embryogenic callus. CpSERK1 and CpSERK2 levels by RT-PCR showed that expression is high in embryogenic, moderate in organogenic, and null in recalcitrant calli. in situ hybridizations showed that the expression of both genes started in clumps of pluripotent stem cells, from which both pre-embryogenic aggregates and organ meristemoids derived, and continued in their trans-amplifying, meristem-like, derivatives. Expression declined in organ meristemoids, in parallel with a partial loss of meristematization. In mature somatic embryos, and in shoot and root primordia, CpSERK1 and CpSERK2 were expressed in meristems, and similar patterns occurred in zygotic embryo and primary meristems in planta. The results point to SERK1 and SERK2 as markers of pluripotency in cyclamen. It is proposed that the high expression of these genes in the trans-amplifying derivatives of the stem cells maintains a pluripotent condition leading to totipotency and, consequently, somatic embryogenesis.

Sorafenib in combination with erlotinib or with gemcitabine in elderly patients with advanced non-small-cell lung cancer: a randomized phase II study.

BACKGROUND: Sorafenib is a small-molecule multitargeted kinase inhibitor that blocks the activation of C-RAF, B-RAF, c-KIT, FLT-3, RET, vascular endothelial growth factor receptor 2 (VEGFR-2), VEGFR-3 and platelet-derived growth factor receptor ß. The aim of this multicenter, randomized phase II study was to evaluate clinical activity and safety of sorafenib in combination with erlotinib or gemcitabine in unselected untreated elderly patients with non-small-cell lung cancer (NSCLC). METHODS: The trial was designed to select the most promising sorafenib-containing combination in previously untreated elderly (≥70 years) stage IIIB or IV NSCLC patients, with performance status of zero to two. Patients were randomly assigned to one of the following combinations: gemcitabine, 1200 mg/m(2) days 1 and 8, every 21 days, for a maximum of six cycles, plus sorafenib, 800 mg/day, until disease progression or unacceptable toxicity (arm 1); or erlotinib, 150 mg/day, plus sorafenib, 800 mg/day, until disease progression or unacceptable toxicity (arm 2). A selection design was applied with 1-year survival rate as the primary end point of the study, requiring 58 patients. RESULTS: Sixty patients were randomly allocated to the study (31 patients in arm 1 and 29 patients in arm 2). After a median follow-up of 15 months, 10 patients [32%, 95% confidence interval (CI) 16% to 49%] in arm 1 and 13 patients (45%, 95% CI 27% to 63%) in arm 2 were alive at 1 year. Median overall survival was 6.6 and 12.6 months in arm 1 and arm 2, respectively. Observed toxic effects were consistent with the expected drug profiles. CONCLUSIONS: The combination of erlotinib and sorafenib was feasible in elderly patients with advanced NSCLC and was associated with a higher 1-year survival rate than the other arm. According to the selection design, this combination warrants further investigation in phase III trials.

Mapping sleeping sickness in Western Africa in a context of demographic transition and climate change.

Human population growth, climate change and economic development are causing major environmental modifications in Western Africa, which will have important repercussions on the epidemiology of sleeping sickness. A new initiative, the Atlas of human African trypanosomiasis (HAT), aims at assembling and geo-referencing all epidemiological data derived from both active screening activities and passive surveillance. A geographic database enables to generate up-to-date disease maps at a range of scales and of unprecedented spatial accuracy. We present preliminary results for seven West African countries (Benin, Burkina Faso, Côte d'Ivoire, Ghana, Guinea, Mali and Togo) and briefly discuss the relevance of the Atlas for future monitoring, control and research activities.

Systemic injection of an H4 receptor agonist induces a decrease in CREB and pCREB levels in the cerebellar vermis and prefrontal cortex in mice.

Studies have shown that an injection with the histamine H4 receptor agonist VUF-8430 modulates emotional memory processes. In the present study, the aim was to verify if intraperitoneal (ip) injection of VUF-8430 (500 ng/kg) in mice affects the synthesis of proteins required for memory consolidation processes by activating the phosphorylation of CREB (pCREB) in classical structures linked to emotional memory (prefrontal cortex, amygdala, and hippocampus) and the cerebellar vermis, a structure that has also been recently implicated in emotional memory. The results obtained using western blot analysis demonstrated that VUF-8430 induced a decrease in CREB and pCREB levels in the cerebellar vermis and prefrontal cortex, suggesting that this dose impaired the activation of cell signaling pathways in these structures. There was no change in protein expression in the amygdala and hippocampus. Our results are preliminary, and further investigations are needed to investigate the role of the H4 receptors in the central nervous system.

Land cover and tsetse fly distributions in sub-Saharan Africa.

This study aims to provide trypanosomiasis-affected countries with standardized datasets and methodologies for mapping the habitat of the tsetse fly (Glossina spp., the disease vector) by customizing and integrating state-of-the-art land cover maps on different spatial scales. Using a combination of inductive and deductive approaches, land cover and fly distribution maps are analysed in a geographic information system (GIS) to estimate the suitability of different land cover units for the three groups (subgenera) of Glossina. All land cover datasets used for and produced by the study comply with the Land Cover Classification System (LCCS). At the continental scale, a strong correlation between land cover and tsetse habitat is found for both the fusca and palpalis groups, whereas a weaker correlation found for the morsitans group may be indicative of less restrictive ecological requirements. At the regional and national levels, thematic aggregation of the multi-purpose Africover datasets yielded high-resolution, standardized land cover maps tailored for tsetse habitat for eight East African countries. The national maps provide remarkable spatial resolution, thematic detail and geographical coverage. They may be applied in subsequent phases of tsetse and trypanosomiasis control projects, including the planning of entomological surveys, actual tsetse control operations and planning for land use in reclaimed areas. The methodology and datasets discussed in the paper may have applications beyond the tsetse and trypanosomiasis issue and may be used with reference to other arthropod vectors, vector-borne and parasitic diseases.

Intra-vermis H4 receptor agonist impairs performance in anxiety- and fear-mediated models.

The neural histaminergic system modulates cognitive performance in various animal models. However, little is known about the effects of the H4 histaminergic receptor in the central nervous system. The purpose of this study was to investigate the effect of histaminergic H4 agonist VUF-8430 microinjection into the cerebellar vermis on the consolidation of emotional memory in mice subjected to the elevated plus maze (EPM) and inhibitory avoidance task (IAT). All experiments were performed on two consecutive days: exposure (T1 and D1) and 24h after, which we called re-exposure (T2 and D2). The animals received saline (SAL) or VUF (0.15 nmol; 0.49 nmol; 1.48 nmol/0.1µl) administered post-exposure. Experiment 1 was conducted in the EPM, and the animals were free to explore the maze for 5min. In T1, immediately after exposure, the pharmacological treatment was given; in T2, there was only re-exposure to the EPM. Experiment 2 involved the IAT, and the pharmacological treatment was provided post-D1; in D2, the animals were only re-exposed to the IAT. In Experiment 1, increased open arm exploration (% open arm entries and% open arms time) for 0.49 and 1.48nmol of VUF were recorded in T2 compared to T1. In Experiment 2, a significant decrease in consolidation latency was recorded for the group that received 1.48nmol of VUF compared to the SAL group in D2. These results indicate that a 1.48nmol VUF microinjection into the cerebellar vermis impaired performance in both models, even though one model was anxiety-mediated (EPM) and the other was fear-mediated (IAT).

Cholinergic agonist reverses H1-induced memory deficit in mice.

This study investigated the effects of bilateral intraamygdalar microinjections of PNU-282987, a nicotinic cholinergic agonist, on anxiety and the reversal of amnesia induced by chlorpheniramine (CPA), an H1 histaminergic antagonist, in mice subjected to the elevated plusmaze (EPM). Two experiments were performed with seventy-nine adult male Swiss mice. The isolated microinjections of PNU-282987 did not produce effects on emotional memory; however, the combined microinjections of PNU-282987 and CPA were able to reverse the deficit in memory induced by CPA (ANOVA, p<0.05). Taken together, these results suggest that intraamygdalar injections of PNU-282987 did not induce effects on anxiety and emotional memory per se; however, concurrent microinjections of PNU-282987 and CPA-reverse amnesia induced-CPA which is suggestive of an interaction between the histaminergic and cholinergic systems in the modulation of emotion memory acquisition in mice.

Intra-amygdala microinjections of chlorpheniramine impair memory formation or memory retrieval in anxiety- and fear-mediated models.

H1 receptor histaminergic antagonist, chlorpheniramine (CPA) participates in cognitive performance in various animal models. However, little is known regarding the effects of CPA microinjection into the amygdala on emotional behavior. The purpose of this study was to investigate whether CPA microinjection into the amygdala has the same effect on two models, one anxiety- and the other fear-mediated, in various memory stages using the elevated plus maze (EPM) and the inhibitory avoidance task (IAT) tests. Two experiments were performed with seventy-two adult male Swiss mice. Behavioral testing was performed on two consecutive days, and in both experiments, before each trial, the animals received bilateral microinjections of saline (SAL) or CPA (0.16 nmol). The animals were re-exposed to the EPM or IAT 24h after the first trial. Four experimental groups were tested: SAL-SAL, SAL-CPA, CPA-SAL and CPA-CPA. In experiment 1, a decreased open arm exploration (% open arm entries, %OAE and% open arms time, %OAT) for SAL-SAL and SAL-CPA was showed, while these measures did not decrease for the CPA-SAL and CPA-CPA groups in Trial 2. In experiment 2, an increase of retention latency in relation to training 2 for the groups SAL-SAL and CPA-SAL and a significant decrease in latency for the group SAL-CPA was revealed. These results indicate that chlorpheniramine microinjection into the amygdala impairs emotional memory acquisition and/or consolidation in the EPM and retrieval of IAT.

Drug quality analysis through high performance liquid chromatography of isometamidium chloride hydrochloride and diminazene diaceturate purchased from official and unofficial sources in Northern Togo.

Trypanocidal drugs remain the most accessible and thus commonly used means of controlling tsetse transmitted animal African trypanosomosis. In Togo, trypanocides are sold on official as well as unofficial markets, but the quality of these trypanocides is undocumented so a drug quality assessment study was conducted from May 2013 to June 2014. Trypanocides supplied by European, Indian and Chinese pharmaceutical companies and sold on official and unofficial markets in Togo were purchased. In total fifty-two trypanocides were obtained, 24 of these samples from official markets and 28 from unofficial markets made up of a total of 36 diminazene diaceturate and 16 isometamidium chloride hydrochloride samples. The samples were analysed in the reference laboratory of the OIE (World Organisation for Animal Health), Laboratory for the Control of Veterinary Medicines (LACOMEV) in Dakar which uses galenic testing and high performance liquid chromatography (HPLC) testing as standard reference analysis methods. The results revealed a high proportion of trypanocides of sub-standard quality on the Togolese market: 40% were non-compliant to these quality reference standards. All of the HPLC non-compliant samples contained lower amounts of active ingredient compared to the concentration specified on the packaging. Non-compliance was higher in samples from the unofficial (53.57%) than from the official markets (25%; p=0.04).The main drug manufacturers, mostly of French origin in the study area, supply quality drugs through the official legal distribution circuit. Products of other origins mostly found on illegal markets present a significantly lower quality.

Feasibility of preoperative chemoradiation in rectal cancer patients aged 70 and older.

In the present study, we report results of 28 rectal cancer patients, aged 70 years and older, treated with preoperative radiotherapy and 5FU concomitant chemotherapy. Twenty-eight out of 136 patients treated in our Department between 1997 and 2004 aged > or = 70 years, mean 73 (range 70-81); 3 T2, 18 T3, 7 T4; 15 N0, 5N1, 8 N2; Radiotherapy (5040 cGy, 28 fractions) was delivered combined with 5FU - based concomitant chemotherapy. Compliance to chemoradiotherapy was excellent. Major acute toxicity (> or = G3) evaluation showed haematological Grade 3 only in 2 patients. No severe acute Gastrointestinal toxicity was observed. All patients underwent surgery without severe perioperative complications. Complete pathological response pT0 was found in 3 patients (11%). Overall T downstaging occurred in 61% of the cases. Mean follow up was 34 months (range 4- 84). Kaplan Meier Overall Survival and Disease Free Survival at 5 years were 74% (95% CI 54 -95) and 65% (95% CI 38-93), respectively. Only 1 patient showed G3 diarrhea according to CTCAE that interfered with his Quality of Life and required hospitalization. In conclusion, concomitant radiochemotherapy 5FU based is safe in rectal cancer patients aged > or = 70 with a good tumour downstaging (61% of patients) and excellent feasibility. No treatment related death was observed.

Dorsal hippocampal microinjection of chlorpheniramine reverses the anxiolytic-like effects of l-histidine and impairs emotional memory in mice.

Several findings have pointed to the role of histaminergic neurotransmission in the modulation of anxiety-like behaviors and emotional memory. The elevated plus-maze (EPM) test has been widely used to investigate the process of anxiety and also has been used to investigate the process of learning and memory. Visual cues are relevant to the formation of spatial maps, and as the hippocampus is involved in this task, experiment 1 explored this issue. Experiment 2 investigated the effects of intraperitoneal (i.p.) injections of l-histidine (LH, a precursor of histamine) and of intra-dorsal hippocampus (intra-DH) injections of chlorpheniramine (CPA, an H1 receptor antagonist) on anxiety and emotional memory in mice re-exposed to the EPM. Mice received saline (SAL) or LH i.p. and SAL or CPA (0.016, 0.052, and 0.16 nmol/0.1 µl) intra-DH prior to Trial 1 (T1) and Trial 2 (T2). No significant changes were observed in the number of enclosed-arm entries (EAE) in T1, an EPM index of general exploratory activity. LH had an anxiolytic-like effect that was reversed by intra-DH injections of CPA. T2 versus T1 analysis revealed that only the lower dose of CPA resulted in impaired emotional memory. Combined injections of LH and CPA revealed that higher doses of CPA impair emotional memory. Taken together, these results suggest that LH and H1 receptors present in the dorsal hippocampus are involved in anxiety-related behaviors and emotional memory in mice submitted to EPM.

Cerebellar vermis H2 receptors mediate fear memory consolidation in mice.

Histaminergic fibers are present in the molecular and granular layers of the cerebellum and have a high density in the vermis and flocullus. Evidence supports that the cerebellar histaminergic system is involved in memory consolidation. Our recent study showed that histamine injections facilitate the retention of an inhibitory avoidance task, which was abolished by pretreatment with an H2 receptor antagonist. In the present study, we investigated the effects of intracerebellar post training injections of H1 and H2 receptor antagonists as well as the selective H2 receptor agonist on fear memory consolidation. The cerebellar vermi of male mice were implanted with guide cannulae, and after three days of recovery, the inhibitory avoidance test was performed. Immediately after a training session, animals received a microinjection of the following histaminergic drugs: experiment 1, saline or chlorpheniramine (0.016, 0.052 or 0.16 nmol); experiment 2, saline or ranitidine (0.57, 2.85 or 5.07 nmol); and experiment 3, saline or dimaprit (1, 2 or 4 nmol). Twenty-four hours later, a retention test was performed. The data were analyzed using one-way analysis of variance (ANOVA) and Duncan's tests. Animals microinjected with chlorpheniramine did not show any behavioral effects at the doses that we used. Intra-cerebellar injection of the H2 receptor antagonist ranitidine inhibited, while the selective H2 receptor agonist dimaprit facilitated, memory consolidation, suggesting that H2 receptors mediate memory consolidation in the inhibitory avoidance task in mice.

Mapping the benefit-cost ratios of interventions against bovine trypanosomosis in Eastern Africa.

This study builds upon earlier work mapping the potential benefits from bovine trypanosomosis control and analysing the costs of different approaches. Updated costs were derived for five intervention techniques: trypanocides, targets, insecticide-treated cattle, aerial spraying and the release of sterile males. Two strategies were considered: continuous control and elimination. For mapping the costs, cattle densities, environmental constraints, and the presence of savannah or riverine tsetse species were taken into account. These were combined with maps of potential benefits to produce maps of benefit-cost ratios. The results illustrate a diverse picture, and they clearly indicate that no single technique or strategy is universally profitable. For control using trypanocide prophylaxis, returns are modest, even without accounting for the risk of drug resistance but, in areas of low cattle densities, this is the only approach that yields a positive return. Where cattle densities are sufficient to support it, the use of insecticide-treated cattle stands out as the most consistently profitable technique, widely achieving benefit-cost ratios above 5. In parts of the high-potential areas such as the mixed farming, high-oxen-use zones of western Ethiopia, the fertile crescent north of Lake Victoria and the dairy production areas in western and central Kenya, all tsetse control strategies achieve benefit-cost ratios from 2 to over 15, and for elimination strategies, ratios from 5 to over 20. By contrast, in some areas, notably where cattle densities are below 20per km(2), the costs of interventions against tsetse match or even outweigh the benefits, especially for control scenarios using aerial spraying or the deployment of targets where both savannah and riverine flies are present. If the burden of human African trypanosomosis were factored in, the benefit-cost ratios of some of the low-return areas would be considerably increased. Comparatively, elimination strategies give rise to higher benefit-cost ratios than do those for continuous control. However, the costs calculated for elimination assume problem-free, large scale operations, and they rest on the outputs of entomological models that are difficult to validate in the field. Experience indicates that the conditions underlying successful and sustained elimination campaigns are seldom met. By choosing the most appropriate thresholds for benefit-cost ratios, decision-makers and planners can use the maps to define strategies, assist in prioritising areas for intervention, and help choose among intervention techniques and approaches. The methodology would have wider applicability in analysing other disease constraints with a strong spatial component.

Dose-finding/phase II trial: bevacizumab, immunotherapy, and chemotherapy (BIC) in metastatic renal cell cancer (mRCC). Antitumor effects and variations of circulating T regulatory cells (Treg).

The aim of this study was to explore the efficacy and toxicities of a combined regimen of bevacizumab plus immunotherapy and chemotherapy (BIC) and the circulating T regulatory cells (Treg) in metastatic renal cell cancer (mRCC). Nephrectomized mRCC patients were enrolled into a multicenter single-arm dose-finding study with five escalated dose levels of chemotherapy with intravenous gemcitabine and 5-fluorouracil associated with fixed intravenous doses of bevacizumab, subcutaneous low doses of interleukin-2, and interferon-α-2a. An expanded cohort (phase II study) was treated at the recommended dose for additional safety and efficacy information according to minimax Simon two-stage design. Blood samples for Treg were collected and evaluated by fluorescence-activated cell sorting (FACS) analysis on cycle 1. Fifty-one patients were entered to receive one of five dose levels. Median age was 58 years (male 67 %, pretreated 49 %): 15 patients were low risk according to Memorial Sloan-Kettering Cancer Center (MSKCC) criteria, while 27 and nine were respectively intermediate- and high-risk patients. More frequent grade 3 and 4 toxicities included nonfebrile neutropenia, thrombocytopenia, and fever. Among patients evaluable for response (49), 29.5 % had partial response and 37 % stable disease. Overall median time to progression and median overall survival were 8.8 and 22.67 months, respectively. We observed a rapid increase in the percentage of Treg after immunotherapy and a reduction after bevacizumab only in patient who obtained a partial response or stable disease. The BIC was feasible, well tolerated, and shown interesting activity. Further studies are needed to explore if Treg could have a role in clinical response in mRCC treated with bevacizumab.

Recovery from unilateral 6-hydroxydopamine lesion of substantia nigra promoted by the neurotachykinin substance P 1-11.

Previous work has indicated that the neurotachykinin substance P may have nootropic and neurotrophic effects in vivo and in vitro raising the possibility that this neuropeptide may promote functional recovery from brain damage. This hypothesis was tested using the unilateral 6-hydroxydopamine lesion of the nigrostriatal dopamine system, as there is close anatomical and functional interaction between dopamine and substance P in this system. Rats were unilaterally injected with 6-hydroxydopamine into the substantia nigra, and, starting with the day after the lesion, were treated daily with peripheral injections of substance P (50 micrograms/kg, i.p.). The analysis of open-field behavior showed that, compared with vehicle-treated control lesions, substance P prevented the lesion-induced ipsiversive asymmetry in turning behavior and accelerated recovery from the ipsilateral asymmetry in thigmotactic scanning. The facilitatory effects of substance P were dependent on the degree of the lesion, as they were observed in animals with subtotal neostriatal dopamine depletions but not in those with near-total depletions. These results are discussed, firstly, with regard to the possible mechanisms of substance P on dopaminergic and non-dopaminergic systems, and secondly, with respect to their possible relevance in the study of neurodegenerative diseases.

Serum concentrations of zinc and selenium in elderly people: results in healthy nonagenarians/centenarians.

Trace elements such as zinc (Zn) and selenium (Se) play an important role in maintaining the metabolic homeostasis in elderly people and the risk of deficiency seems to increase in proportion to the age. Zn and Se concentrations, as indices of the micronutrient status in healthy subjects over 90 years, are scarcely analyzed and could represent a model for studying the physiology of successful aging. Our aim was to investigate Zn and Se concentrations in the healthy persons over the age of 90 years. One hundred and fifty two subjects volunteered for the study. They were divided into two groups: 90 non-institutionalized nonagenarians/centenarians (91-110 years) (group A) and 62 elderly subjects (60-90 years) used for comparison (group B). Serum concentrations of Zn and Se were determined, respectively, by flame atomic absorption spectrophotometry (FAAS) and electrothermal atomic absorption spectrophotometry (ETAAS). The effect of age and sex on ion concentrations was investigated. Mean values+/-standard deviation of Zn and Se concentrations in the group A were 11.97+/-2.00 and 0.87+/-0.28 micromol/l, respectively. A significant decrease of Se and Zn values was demonstrated in group A, when compared with group B, in both males and females. However, 84.4% of the 'healthy' nonagenarians/centerians had both Zn and Se concentrations equal to or greater than the lowest values of the elderly group and only 3.3% of cases showed both Zn and Se deficiencies. Consequently, a prospective and follow-up evaluation of Zn and Se could be proposed as a good index for a correct monitoring of the micronutrient deficiencies, that could represent an early sign of disease.

Haloperidol and chlorpheniramine interaction in inhibitory avoidance in goldfish.

The purpose of this study was to investigate a possible interaction between histaminergic and dopaminergic systems in learning and memory processes, in an inhibitory avoidance test in goldfish. Haloperidol, a dopaminergic antagonist, was administrated pre-training and the chlorpheniramine (CPA), a histaminergic antagonist, post-training. The inhibitory avoidance procedure was performed in 3 days, using a rectangular aquarium divided into two compartments (black and white), with a central door. On the first day, the animals were habituated for 10 min. On the second day, they were injected with 2 mg/kg of haloperidol or dimethyl sulfoxide (DMSO) 20 min before training. Then, the animals were placed in the white compartment, the central door was opened and the time spent for crossing between compartments was recorded. After the fish crossed the line between compartments a 45 g weight was dropped. This procedure was done five times in a row. Immediately after the fifth trial, the fish were injected intraperitoneally (i.p.) with either saline or CPA (0.4, 1.0, 4.0, 8.0 or 16 mg/kg). On the next day (test) the time to cross was recorded again. On the training trials, the animals treated with DMSO or haloperidol presented a significant increase in the latencies indicating learning (Friedman P = 0.0062 and 0.0001). The latencies in the test day showed that groups pre-treated with haloperidol and treated with CPA presented a dose-dependent increase in latencies, and those treated with the 16 mg/kg CPA group showed a significant increase (ANOVA two-way followed by Student-Newman-Keuls (SNK) P < 0.01). Thus, it can be suggested that the facilitatory action occurs due to an additive interaction between both systems, in a dose-dependent way.