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Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG [Abstract] The Atlantic coast of Galicia (NW Spain) is a high-energy environment where shingle beaches are currently developing. These coarser sediments alternate with sandy deposits which are also considered as beaches typical of a low-energy environment. The physical association of both types of sediment with contrasted sedimentary significance raises problems of interpretation. The study of four outcrops of fossil aeolianites on this coast has allowed us to reconstruct their evolution from the end of the Upper Pleistocene to the present day. Their chronology, estimated by optically stimulated luminescence between 35 and 14 ky at the end of the last glaciation (MIS2), coincides with a local sea level 120 m below the present one. This implies a coastline shifted several kilometres from its current location and the subaerial exposure of a wide strip of the continental shelf covered by sands. The wind blew sand to form dunes towards the continent, covering the coastal areas, which then emerged with no other limitation than the active river channels. Sea-level rise during the Holocene transgression has progressively swamped these aeolian deposits, leaving only flooded dunes, relict coastal dunes and climbing dunes on cliffs up to 180 m high. The aeolian process continued as long as there was a sandy source area to erode, although accretion finished when the sea reached its current level (Late Holocene). Since then, the wind turned from accretion to erosion of the dunes and sand beaches. This erosion exposes the older shingle beaches (probably of Eemian age) buried under the aeolian sands, as well as old, submerged forest remains and megalithic monuments. The destruction of sand beaches and dunes currently observed along the Galician coast is linked, according to most researchers, to anthropogenic global warming. However, their management should consider these evolutive issues. This research has been funded and supported by Consellería de Cultura, Educación e Ordenación Universitaria, Xunta de Galicia (programmes ED431B 2018/47 and ED431B 2021/17) through the Grupo Interdisciplinar de Patrimonio Cultural e Xeolóxico (CULXEO). Thanks to Universidade da Coruña/Consorcio Interuniversitario del Sistema Universitario de Galicia (CISUG) for Open Acces funding Xunta de Galicia; ED431B 2018/47 Xunta de Galicia; ED431B 2021/17

Background Before initiating cancer therapy, a diagnostic tumor tissue sample evaluated within a pathology laboratory by a pathologist is essential to confirm the malignancy type and provide key prognostic factors that direct the treatment offered. Methods Pathology evaluation includes multiple expensive reagents, complex equipment, and both laboratory and pathologist technical skills. By using breast cancer as an example, at a minimum, key tumor prognostic information required before the initiation of treatment includes subtype, tumor grade, tumor size, lymph node status when possible, and biomarker expression determined by immunohistochemistry for estrogen receptor. The additional determination of biomarker expression of progesterone receptor and human epidermal growth factor receptor (HER2) is the standard of care in high-resource settings, but assays may not be affordable in low-income and middle-income countries. Results With positive tests, patients are eligible for either tamoxifen (for estrogen receptor-positive/progesterone receptor-positive cancers) or monoclonal antibody therapy (for HER2-positive cancers). For settings in which endocrine therapy and/or HER2-targeted therapy is unavailable, biomarker studies have no utility, and high-resource setting standards for pathology evaluation and reporting are unachievable. Resource-stratified pathology evaluation guidelines in cancer diagnosis have not been developed, in contrast to excellent comprehensive, resource-stratified clinical guidelines for use in low-income and middle-income countries, and these are long overdue. Conclusions The challenges of pathology evaluation in the context of global health are being met by innovative solutions, which may change the face of pathology practice.

Motivation Savings are an important but often overlooked component of financial inclusion. While women are less active than men in the formal financial sector there is little understanding about their ability to accumulate savings. Purpose We hypothesize that a woman’s individual economic status, measured by her property ownership, is an important driver of her ability to save. Approach and Methods Women are considered as savers in the formal sector only if they have savings above a minimum threshold. Three measures of women’s asset ownership are used: two capture their absolute property status and one their relative status in the household. The data are obtained from three large‐scale surveys that collected individual‐level asset data in Ecuador, Ghana and the Indian state of Karnataka. Logistic regression models are employed to examine the relationship between women’s property ownership and accumulation of savings. Findings The absolute value of a woman’s physical assets and her share of household physical wealth are correlated with being able to accumulate formal savings. Women’s relative wealth status is more strongly related to their savings, along with education, paid employment and group membership. Conclusions Women’s intrahousehold status, defined by their relative wealth, is critical to determining their ability to save in formal accounts. Policy Implications Interventions that boost women’s bargaining power, by increasing their property ownership, should be encouraged, along with greater efforts to improve girls’ access to quality education. Functional literacy training for older women can both reduce barriers to accessing financial institutions and create awareness of their benefits. Constraints to women’s participation in the labour force should be removed in tandem with interventions to reduce gender earnings gaps.

Haiti, located on the western portion of the Caribbean island Hispaniola, faces many geopolitical and healthcare issues. Haiti carries the highest maternal mortality rate in the Western Hemisphere, and many women and children lack access to healthcare (WHO, 2015b). Various obstacles to access exist, including economics, transportation, and low ratios of healthcare providers to citizens. Haiti is one of the poorest countries in the world, with an annual gross national income per capita of $820 in 2014 (The World Bank, 2015b), making economics a barrier to accessing health care (The World Bank, 2015a). According to the International Monetary Fund (2015), Haiti lacks infrastructure and an appropriate number of health professionals for each inhabitant. Data available from the World Health Organization (WHO, 2015c) show that in 1998 there were 0.25 physicians per 1,000 inhabitants and 0.107 nurses and midwifery personnel per 1,000 inhabitants, making it difficult for Haitians to find a healthcare provider.The maternal mortality rate in Haiti is 380 deaths per 100,000 live births, compared to 85 deaths per 100,000 live births in the Latin American and Caribbean region (Pan American Health Organization, 2014). The adolescent fertility rate per 1,000 women was 65, based on the latest data available from 2009 (WHO, 2015a). In addition, no formal reports on abortion and its occurrence are available for the country. In particular, data about beliefs and practices as they relate to abortion in a country where it is an illegal practice could help illuminate some of the needs of the Haitian people (Martin, 2013). Because of the social stigma, unsafe abortions disproportionately affect developing nations, with more than 55% of abortions being performed in unsafe environments, compared to 92% of abortions in developed countries being performed in safe environments (Sedgh, Henshaw, Singh, Ahman, & Shah, 2007).Haitian women state that abortion stigma prevents access to care, and following abortion women often present with symptoms for more than a week before pursuing necessary postabortion care (Berry-Bibee et al., 2014). Generally, Haitian women do not have access to contraception, abortion is illegal, and women who seek an abortion endure a social stigma both culturally and religiously (Maternowska, 2006).Abortions in Haiti are governed by provisions of the Haitian Penal Code. The law regulating abortion is based on Article 317 of the French Penal Code of 1810. Under this law, any person performing an abortion is subject to imprisonment, and a medical professional who performs abortions is subject to forced labor (United Nations, 2011).With the cultural beliefs and judicial rulings in Haiti making abortion both illegal and illicit, many women seek clandestine abortions. International studies have revealed unsafe conditions for women seeking abortions, with many women acquiring severe infections postabortion and needing to go to tertiary care facilities when possible, potentially increasing women's mortality (Berry-Bibee et al., 2014; Martin, 2013; Maternowska, 2006; Sundaram, Juarez, Bankole, & Singh, 2012).In underdeveloped nations, such as Haiti, with strict abortion laws, women are susceptible to unsafe conditions for abortions. Often in these countries, women receive abortion services from people lacking the necessary skills and in environments deemed below the minimum medical standards. The legality of abortion plays a role in the safety of abortion procedures performed yet shows no correlation with the number of abortions performed (Sedgh et al., 2007).Women feeling the burden of childrearing often resort to herbal remedies and other concoctions to terminate pregnancy (Editorial, 2009; Maternowska, 2006). Often, women with available funds go to a private hospital or clinic and receive an abortion with anesthesia. However, women without monetary resources resort to herbal potions and unsafe abortion practices. …

Objective This study examined whether changes in adipocyte long chain fatty acid (LCFA) uptake kinetics explain the weight regain increasingly observed following bariatric surgery. Methods Three groups (10 patients each) were studied: patients without obesity (NO: BMI 24.2 ± 2.3 kg m−2); patients with obesity (O: BMI 49.8 ± 11.9); and patients classified as super-obese (SO: BMI 62.6 ± 2.8). NO patients underwent omental and subcutaneous fat biopsies during clinically indicated abdominal surgeries; O were biopsied during bariatric surgery, and SO during both a sleeve gastrectomy and at another bariatric operation 16 ± 2 months later, after losing 113 ± 13 lbs. Adipocyte sizes and [3H]-LCFA uptake kinetics were determined in all biopsies. Results Vmax for facilitated LCFA uptake by omental adipocytes increased exponentially from 5.1 ± 0.95 to 21.3 ± 3.20 to 68.7 ± 9.45 pmol/sec/50,000 cells in NO, O, and SO patients, respectively, correlating with BMI (r = 0.99, P

Background After the 2010 earthquake in Haiti, the large number of persons with major limb damage, amputations, shock, trauma, anxiety and depression placed a severe strain on mental health (MH) services. Purpose This qualitative study describes the impact and acceptability of a Mental Health Training Program (MHTP) implemented in the north of Haiti after the earthquake. Methods A total of 113 healthcare workers (HCWs) participated in a training program designed to build local MH care capacity. The training curriculum draws on literature related to MH and the impact of the Haiti earthquake. Two focus groups were conducted with 16 HCWs; discussions centred on the personal and professional impact and acceptability of the training program. Discussion Results demonstrated that the MHTP changed the HCWs' perceptions about MH issues and provided them with the knowledge and skills to respond to growing community MH needs. Acceptability of the MHTP was related to the content covered, to the delivery mode of the content and to the cultural appropriateness of the program. Conclusions Disasters of different types will continue to occur and to impact MH in communities around the world. MH training will allow nurses to quickly and effectively respond to disasters. A coordinated emergency plan that is subject to frequent review, rehearsal and evaluation is also essential.

The brain of adult teleost fish exhibits several unique and interesting features, notably an intense neurogenic activity linked to persistence of radial glial cells acting as neural progenitors, and a high aromatase activity supported by strong expression of the cyp19a1b gene. Strikingly, cyp19a1b expression is restricted to radial glial cells, suggesting that estrogens are able to modulate their activity. This raises the question of the origin, central or peripheral, of C19 androgens available for aromatization. This study aimed to investigate the activity and expression of other main steroidogenic enzymes in the brain of adult zebrafish. We demonstrate by high-performance liquid chromatography that the zebrafish brain has the ability to convert [³H]-pregnenolone into a variety of radiolabeled steroids such as 17OH-pregnenolone, dehydroepiandrosterone, androstenedione, testosterone, dihydro-testosterone, estrone, estradiol, progesterone, and dihydro- and tetrahydro-progesterone. Next, we show by in situ hybridization that messengers for key steroidogenic enzymes, such as Cyp11a1 (P450(SCC)), 3β-Hsd, Cyp17 and Cyp19a1b, are widely expressed in the forebrain where they exhibit an overall similar pattern. By combining aromatase B immunohistochemistry with in situ hybridization, we show that cyp11a1, 3β-hsd and cyp17 messengers are found in part in aromatase B-positive radial processes, suggesting mRNA export. This set of results provides the first demonstration that the brain of fish can produce true neurosteroids, possibly in radial glial cells. Given that radial glial cells are brain stem cells during the entire lifespan of fish, it is suggested that at least some of these neurosteroids are implicated in the persisting neurogenic process.

The initiation sensitivity of cyclotrimethylenetrinitramine (RDX) was investigated as a function of crystal size. For this study, RDX powders with mean crystal sizes of ca. 200 and 500 nm were prepared by rapid expansion of supercritical solutions (RESS) with carbon dioxide as the solvent. Initiation sensitivity testing to impact, sustained shock, and electrostatic discharge stimuli was performed on uncoated as well as wax-coated specimens. The test data revealed that in a direct comparison to coarser grades the nanocrystalline RDX-based samples were substantially less sensitive to shock and impact stimuli. Furthermore, the 500 nm RDX-based specimens exhibited the lowest sensitivity values, an indication that minima in shock and impact sensitivities with respect to crystal size exist.

In contrast to mammals, teleost fish have a very labile genetic sex determination. Sex differentiation is influenced by a combination of hormonal, social and environmental factors and teleost fishes exhibit many examples of hermaphroditism. This means that the brain of fish is not irreversibly sexualized early in life. This review aims at highlighting some unique features of fish that may explain their brain sexual plasticity. Unlike mammals, in which brain aromatase activity decreases after birth, adult teleosts exhibit an intense aromatase activity due to strong expression of one of two aromatase genes (aromatase A or cyp19a1a and aromatase B or cyp19a1b) that arose from a gene duplication event. Interestingly, aromatase B is only expressed in radial glial cells (RGC) of adult fish. These cells persist throughout life and act as progenitors in the brain of both developing and adult fish. In agreement with the fact that brain aromatase activity is correlated with sex steroid levels, the high expression of cyp19a1b is due to an autoregulatory loop through which estrogens and aromatizable androgens upregulate aromatase expression. Given the well-established roles of estrogens and aromatase on brain sexualization, these features suggest that the brain of fish conserves properties of embryonic mammalian brain throughout life - high neurogenic activity and high aromatase expression in progenitor cells correlated with sex steroid levels. The permanent dialogue between the brain and the gonad would permit sex changes and thus the emergence of a variety of reproductive strategies. Other hypotheses are also discussed.

Analysis of elution profiles of enzymatic and CNBr digests of kappa-caseins C and E, and sequencing of most relevant peptides allowed the chemical characterization of both genetic variants. They differ from their B and A allelic counterparts by a single substitution, His97/Arg and Gly155/Ser, respectively. Electrophoretic behaviour of the investigated C and E variants was in good agreement with the observed amino acid replacements.

The present study aimed at defining the best scheme of administration of the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor-positive modulator (S)-2,3-dihydro-[3,4]-cyclopentano-1,2,4-benzothiadiazine-1,1-dioxide (S 18986) [once daily (o.d.) administration of 1 mg/kg for 3 days vs. three times daily (t.i.d.) administration of 0.3 mg/kg for 3 days] to get an optimal procognitive activity in the object recognition task in rats. Memory performance [Recognition Index (RI)] of rats was significantly improved 1 h (RI = 41%, P < 0.01) and 3 h (RI = 46%, P < 0.001) following oral administration of S 18986 (1 mg/kg, o.d.) when compared with animals receiving the vehicle (RI = 6%). When the interval between administration and testing was increased to 6 h and 9 h, no statistically significant improvement in memory performance was observed (RI = 42% for 6 h and RI = 18% for 9 h vs. 20% for the vehicle group). When S 18986 was administered at 0.3 mg/kg t.i.d., no statistically significant improvement in memory performance was observed (RI = 36%). These findings show a long-lasting efficacy of the AMPA receptor allosteric modulator in the object recognition task despite a short half-life in plasma and in brain (approximately 1 h). Accordingly, multiple administrations of S 18986 are not required to obtain a maximal efficacy in this paradigm, because a o.d. schedule of administration leads to a powerful procognitive activity.

The circadian clock in the suprachiasmatic nucleus (SCN) controls day-to-day physiology and behavior by sending timing messages to multiple peripheral oscillators. In the pineal gland, a major SCN target, circadian events are believed to be driven exclusively by the rhythmic release of norepinephrine from superior cervical ganglia (SCG) neurons relaying clock messages through a polysynaptic pathway. Here we show in rat an SCN-driven daily rhythm of pineal MAPK activation that is not dependent on the SCG and whose maintenance requires vitamin A as a blood-borne factor. This finding challenges the dogma that SCG-released norepinephrine is an exclusive mediator of SCN-pineal communication and allows the assumption that humoral mechanisms are involved in pineal integration of temporal messages.

Lactococcus lactis is a Gram-positive bacteria, which belongs to the group of lactic acid bacteria among which several genera play an essential role in the manufacture of food products. Cytosolic proteins of L. lactis IL1403 cultivated in M17 broth have been resolved by two-dimensional gel electrophoresis using two pH gradients (pH 4-7, 4.5-5.5). More than 230 spots were identified by peptide mass fingerprints, corresponding to 25% of the predicted acid proteome. The present study made it possible to describe at the proteome level a significant number of cellular pathways (glycolysis, fermentation, nucleotide metabolism, proteolysis, fatty acid and peptidoglycan synthesis) related to important physiological processes and technological properties. It also indicated that the fermentative metabolism, which characterizes L. lactis is associated with a high expression of glycolytic enzymes. Thirty-four proteins were matched to open reading frames for which there is no assigned function. The comparison at the proteome level of two strains of L. lactis showed an important protein polymorphism. The comparison of the proteomes of glucose- and lactose-grown cells revealed an unexpected link between the nature of the carbon source and the metabolism of pyrimidine nucleotides.

The distribution of D(2)R (dopamine D(2) receptor) mRNAs was studied in the forebrain of maturing female rainbow trout by means of in situ hybridization using a (35)S-labeled riboprobe (810 bp) spanning the third intracytoplasmic loop. A hybridization signal was consistently obtained in the olfactory epithelium, the internal cell layer of the olfactory bulbs, the ventral and dorsal subdivisions of the ventral telencephalon, and most preoptic subdivisions, with the notable exception of the magnocellular preoptic nucleus, and the periventricular regions of the mediobasal hypothalamus, including the posterior tuberculum. In the pituitary, the signal was higher in the pars intermedia than in the proximal and the rostral pars distalis, but no obvious correspondence with a given cell type could be assigned. Labeled cells were also located in the thalamic region, some pretectal nuclei, the optic tectum, and the torus semicircularis. These results provide a morphologic basis for a better understanding on the functions and evolution of the dopaminergic systems in lower vertebrates.

C57 and DBA mice were trained in a crossed maze to assess possible strain differences in place or response learning as a function of training duration (8 or 17 days) and extramaze cueing conditions. The first condition consisted of a diffuse visually cued environment (rich cueing). The second was the same plus an explicit visual cue marking the direction of the baited arm (rich cueing plus cue). The third was a featureless environment (poor cueing). During training, mice were released from the south arm and rewarded in the east arm. Probe trials on which mice were released from the north arm and allowed to choose either the east (place learning) or the west (response learning) arm were given either on the ninth (PT1) or the eighteenth (PT2) days. Strain x context differences in the activation of the dorsal hippocampus and the dorsolateral striatum were examined by analyzing Fos expression following each probe trial. Results first showed that C57 were essentially place-learners, whereas no learning modality was predominant in DBA, except on the PT2 run with the explicit cue available. Examination of Fos expression in C57 trained under "rich cueing" and "rich cueing plus cue" conditions revealed a strong and parallel increase of immunoreactivity in the hippocampus and dorsolateral striatum following PT1 that decreased under PT2. In that strain, the similar time-course variation of Fos expression in both areas suggests a simultaneous involvement of hippocampal- and striatal-based learning mechanisms, even if those controlled by the hippocampus were prevailing on those controlled by the dorsolateral striatum. In DBA mice, however, the absence of any preferential learning modality was associated with 1) a consistent hippocampal activation persistent across probe trials, and 2) a global superior activation of the dorsolateral striatum. Distinct patterns of Fos expression were therefore associated with every strain-specific learning modality. In each strain, however, each modality was found to be remarkably stable, whatever the training duration and the cueing conditions.

BACKGROUND Total parenteral nutrition (TPN) is used for critically ill patients undergoing surgery, after trauma, or during disease conditions that favor oxidative stress. We studied the effect of TPN on liver oxidative metabolism and antioxidant defenses in rats, and we compared the effect of soybean oil- and olive oil-based diets. METHODS Seven-week-old rats (n = 28) were divided into four groups. Two experimental groups received a TPN solution containing soybean oil (TPN-S) or a mixture of olive/soybean oil, 80/20 (TPN-O), IV for 6 days. Orally fed animals received a solid diet including soybean oil (Oral-S) or olive/soybean oil, 80/20 (Oral-O). The following parameters were measured: DL-alpha-tocopherol, vitamin A, malondialdehyde and thiobarbituric acid reactive substances (MDA-TBARS), and total radical-trapping antioxidant parameter (TRAP) in serum; DL-alpha-tocopherol, vitamin A, glutathione (GSH), and catalase (Cat) activity in liver homogenate; fatty acids from phospholipid, cytochrome P-450 content, NADPH-cytochrome c2 reductase activity in liver microsomes; superoxide dismutase (SOD), glutathione peroxidase (Gpx), glutathione reductase (GR), glutathione transferase (GST), and glucose-6-phosphate dehydrogenase (G6PD) in liver cytosol. RESULTS The soybean or olive oil diets modified the liver microsomal fatty acid phospholipid composition, but the unsaturation index remained unchanged. TPN specifically increased the saturation of the membrane. The cytochrome P-450 level and the NADPH-cytochrome c2 reductase, SOD, Gpx, Cat, and GST activities were unchanged by soybean oil or olive oil diet but decreased receiving TPN. CONCLUSIONS In rats, TPN decreased the liver oxidative metabolism and enzymatic antioxidant defenses. This may be related to saturation of the liver microsomal fatty acids.

The present study analysed the effects of the stage of learning of an appetitive operant conditioning task on the spatial and temporal patterns of c-Fos protein levels in the brain of BALB/c mice. c-Fos levels were assessed by immunohistochemistry at either 60, 120 or 180 min after either the first, the second or the fifth daily training session and compared to sham animals. The results show an increase of c-Fos-positive nuclei in several subcortical and cortical brain regions, 60-min post-acquisition. Because these activations were a function of task mastery, the data indicate that they were specifically related to learning. Following the first acquisition session, significant increases in c-Fos-positive neurons were observed in the dorsal hippocampus (CA3), anterior cingulate, occipital and parietal cortices. Following the second daily training session, c-Fos was highly expressed in some subcortical regions, the hippocampus, the subiculum, the entorhinal, and posterior cingulate areas. Moreover, a significant correlation was found between the progression of performance from day 1 to day 2 and c-Fos expression on the hippocampal CA1 subfield. Following complete acquisition, no further task-dependent increases in c-Fos-labelled nuclei was observed in any brain region sampled, suggesting that the intervention of c-Fos-induced mechanisms in the consolidation process were terminated. The training stage-dependent changes in regional post-training c-Fos expression in the hippocampus and the connected limbic regions suggest that this neuronal network is actively engaged in memory consolidation processes.

Lactococcus lactis is a widely used bacteria in dairy industry, specially in cheese ripening. Numerous lactococcal enzymes and proteins are involved in this process. Proteomics makes it possible to deal with a high number of proteins and identify modification of their patterns in two-dimensional (2-D) gels. However, an annotated reference map is necessary prior to analyzing protein variations. We have begun to construct such a map in easily reproducible conditions and identify proteins.

Tetrapod vertebrates express three neuropeptide Y (NPY)-related peptides: NPY, peptide YY (PYY), and pancreatic polypeptide (PP). Both NPY and PYY mRNA have been localized in the brain of tetrapods whereas PP expression is restricted to the pancreas. Some teleost fish commonly produce NPY and PYY but pancreatic peptide Y (PY) instead of PP. Both NPY and PYY mRNAs are widely distributed in the brain of non-tetrapod species, but no information about PY central expression is available. In the present study, molecular riboprobes were used to study PYY and PY mRNA central distribution in the sea bass (Dicentrarchus labrax). PYY and PY gene expression was predominantly detected within the sea bass forebrain. Telencephalic PYY gene expression was restricted to the ventral part of the ventral telencephalon, and no PY expression was detected in the cerebral hemispheres. Both PYY and PY mRNAs were found within the preoptic area and lateral hypothalamus. Distinct PY or PYY mRNA cell groups were localized in the pretectal area and synencephalon or posterior tubercle, respectively. Caudally, PY gene expression was found in the medial reticular formation, whereas PYY transcripts were localized within the vagal lobe. The results demonstrate that vertebrate brain expresses three NPY-related genes and further support the hypothesis that PP and PY arose by independent gene duplications from PYY. The receptor system of the NPY family as well as gene expression within the main hypophysiotropic and feeding behavior areas suggest an involvement of both peptides in the control of food intake and pituitary secretion., We are grateful to Dr. Anglade and Dr. Mazurais for their technical advice. During part of this work J.M.C.-R. was the recipient of a fellowship from the Balaguer-Gonel Foundation. Grant sponsor: CICYT; Grant number: CYTMAR MAR 95-1888-C03-01;Grant sponsor: the Balaguer-Gonel Foundation

To better define the role of melatonin in fish, we have compared in detail the distribution of 2-[125I]iodomelatonin binding sites with gene expression for melatonin receptor subtypes in a widely studied seasonal species, the rainbow trout. Three distinct partial sequences of the melatonin receptor gene were cloned from trout genomic DNA. Two of the sequences corresponded to the Mel1a receptor subtype, and one corresponded to the Mel1b receptor subtype. Analysis of numerous clones failed to find a sequence equivalent to the Mel1c receptor subtype. Comparison of receptor gene expression with 2-[125I]iodomelatonin binding distribution indicated dendritic transport of the receptor. Melatonin receptors were associated predominantly with visually related areas of the trout brain, such as the thalamic region, the pretectal area, and the optic tectum. The pituitary was devoid of 2-[125I]iodomelatonin binding, and melatonin receptor gene expression was not detectable. It would appear from the results of the present study that melatonin in this species is involved primarily in the processing of visual signals. How melatonin interacts with circannual rhythms of growth and reproduction is unclear, although a direct interaction between melatonin and the hypothalamopituitary axis is not clearly indicated. J. Comp. Neurol. 409:313–324, 1999. © 1999 Wiley-Liss, Inc.

P2 nucleotide receptor expression in cultured human retinal pigment epithelial (RPE) cells was investigated using the photoaffinity ATP analog BzATP, polymerase chain reaction of reverse-transcribed RNA (RT-PCR) and fura-2 fluorescence measurement of changes in intracellular free calcium concentration ([Ca2+]i). In experiments carried out in RPE cells at passage 10-15, addition of micromolar concentrations of ATP, UTP, and ATPgammaS to RPE cells resulted in a rapid, transient 3.5-fold increase in [Ca2+]i followed by a prolonged elevation that was twofold above the original baseline. Similar results were obtained from cells at passage 2. Characteristics of nucleotide-stimulated calcium mobilization in RPE cells, including partial inhibition by pertussis toxin, suggest that a G protein-coupled receptor mediates this response. Consistent with the expression of a P2Y2 nucleotide receptor subtype in RPE cells, [alpha-32P]BzATP labeled a 53-kDa protein in plasma membranes, and RT-PCR revealed the presence of P2Y2 receptor RNA. Adenosine had no effect on [Ca2+]i in RPE cells, indicating that the A2 subtype of P1 receptor described previously in human RPE is not involved in the response to nucleotides. Together the results indicate that human RPE cells express functional P2Y2 nucleotide receptors.

A double immunocytochemical procedure, with two different chromogens, was used to compare the respective distributions of estrogen receptor-immunoreactive cells and gonadotrophin-releasing hormone-immunoreactive neurons on the same sections of the brains of adult male and female rainbow trout (Oncorhynchus mykiss). Estrogen receptor-immunoreactive cells were observed in the ventral and lateral telencephalon, the preoptic region, the mediobasal hypothalamus, and the ventromedial thalamic nucleus. Gonadotrophin-releasing hormone immunoreactive perikarya were detected in the olfactory bulbs, the ventral telencephalon, the preoptic area, and the mediobasal hypothalamus. Double-staining studies showed that, although some estrogen receptor-positive cells were in close proximity to gonadotrophin releasing hormone-immunoreactive perikarya, careful examination of 550 gonadotrophinreleasing hormone-positive cells from five adult females and two adult males failed to demonstrate any evidence that gonadotrophin-releasing hormone neurons coexpress estrogen receptor in the brain of the rainbow trout. The present study provides, for the first time in teleosts, morphological evidence that gonadotrophin-releasing hormone neurons do not represent major direct targets for estradiol, suggesting that the positive feedback effects of estradiol onto the gonadotrophin-releasing hormone system are likely to be conveyed via other cell populations. © 1995 Wiley-Liss, Inc.

Clinical symptoms in Parkinson's disease do not appear until almost total depletion of dopamine has occurred in the striatum, suggesting the existence of compensatory mechanisms to offset the loss of nigrostriatal dopaminergic neurons. This compensation has been attributed mainly to an increased turnover of dopamine in the remaining dopaminergic neurons. Besides this biochemical phenomenon intrinsic to dopaminergic neurons, we tested whether morphological changes in the nerve afferents to the dopaminergic neurons could participate in these compensatory mechanisms. The afferents to the dendrites of dopaminergic neurons were analyzed ultrastructurally in the substantia nigra of parkinsonian patients and matched controls, using simultaneous histochemical detection of acetylcholine-like cation and tyrosine hydroxylase. The size of acetylcholine-like cation-containing terminals in contact with dopaminergic dendrites increased significantly by 38% in the substantia nigra of parkinsonian patients; whereas their number per section of dopaminergic dendrite showed an increase of 60%, although not reaching statistical significance. The number of the terminals devoid of acetylcholine-like cation per section of dopaminergic dendrite decreased significantly by 52% in the substantia nigra of parkinsonian patients. These results suggest (1) a plasticity of excitatory cholinergic neurons targeting nigral dopaminergic neurons and (2) an involution of noncholinergic nerve terminals, mostly originating from inhibitory nigral, pallidal, and striatal GABAergic neurons. The findings provide evidence of a capacity for neuronal plasticity in the elderly human brain, even in the presence of neurodegenerative disorders.

Galanin was purified from an extract of the stomach of the rainbow trout, Oncorhynchus mykiss, and its primary structure was established as Gly-Trp-Thr-Leu-Asn-Ser- Ala-Gly-Tyr-Leu10-Leu-Gly-Pro-His-Gly-Ile-Asp-Gly-His-Arg20- Thr-Leu-Ser-Asp- Lys-His-Gly-Leu-Ala. Trout galanin shows six amino acid substitutions compared with pig galanin, but the N-terminal region (residues 1-14) has been fully conserved. The distribution of galanin-immunoreactive (GAL-IR) structures in the trout brain and pituitary was studied via immunohistochemistry. GAL-IR cell bodies were observed only in the caudal telencephalon, the preoptic region, and the mediobasal hypothalamus. GAL-IR fibers, however, are widely distributed throughout the brain, with a much lower density in the midbrain and posterior brain than in the tel- and diencephalon. Particularly dense innervation of the mediobasal hypothalamus, the ventral and supracommissuralis parts of the caudal telencephalon, and the region above and below the anterior commissure was observed. A heavy innervation of the pituitary was consistently detected. GAL-IR fibers were present in neurohypophyseal digitations of both the anterior and intermediate lobes with highest density in the region of the proximal pars distalis, where growth hormone and gonadotropic cells are located. Fibers were also seen in digitations of the rostral pars distalis, in particular between the prolactin follicles. The distribution of GAL-IR neurons in the central nervous system and pituitary of the trout suggests that the peptide may exercise an important role in the regulation of neuroendocrine functions, particularly those related to reproduction.

The distribution of neurotensin (NT) was studied in the brain of three species belonging to the three major classes of cold-blooded vertebrates: teleost fishes (Carassius auratus), anuran amphibians (Hyla meridionalis), and reptiles (Gallotia galloti; Lacertidae). By using antibodies directed against synthetic bovine NT in the three species, immunoreactive cell bodies were discovered mostly in the telencephalon and diencephalon, in particular at the level of the preoptic region the mediobasal hypothalamus, and the thalamus. In the frog and the lizard, additional immunoreactive (ir) structures were observed in the optic tectum and the tegmentum of the mesencephalon. In the goldfish pituitary, an extensive innervation was consistently observed at the level of the rostral pars distalis, whereas in both frog and lizard, positive fibers were only detected in the external layer of the median eminence. In the three species there is a striking overlap between the distribution of the NT-ir cell bodies and that of the target cells for sexual steroids. The results are discussed in relation with those reported in birds and mammals, and with the possible interactions among NT, sexual steroids, and the neuroendocrine control of pituitary hormone release, in particular prolactin and gonadotrophin.

The mechanisms that lead ultimately to neuronal death in pathological ageing of the brain remain mostly unknown as in the case of Parkinson's disease where there is a progressive and selective loss of dopaminergic neurons within the substantia nigra. Dopamine-expressing PC12 cells that were neuronally differentiated by nerve growth factor treatment were chosen as a culture model in which to study some of the changes that may occur during the course of the degenerative process. They were exposed to the calcium ionophore A23187 in order to produce a sustained rise in cytoplasmic calcium, a phenomenon related to various pathological conditions. The degenerative effects of the ionophore were dose- and time-dependent. They were characterized by early fragmentation of the neurites followed ultimately by a loss in cell viability. Biochemical changes, such as a decrease in [3H]dopamine uptake and modulations of the tyrosine hydroxylase gene, were detected before macroscopic evidence of cell suffering (e.g. neurite fragmentation) could be observed. Although an ongoing degenerative process was occurring in cell somata, PC12 cells were able to recover upon ionophore withdrawal. Characteristics of apoptosis such as chromatin condensation and DNA fragmentation were detectable in a small population of dying cells. DNA fragmentation could be prevented by the endonuclease inhibitor aurintricarboxylic acid. New protein synthesis was not required, as cycloheximide failed to prevent degeneration. Taken together, these results suggest that differentiated PC12 cells react to calcium stress through a sequence of regulatory processes which appears to be independent of the apoptotic pathway.

The brain of the sturgeon has recently been shown to contain at least two forms of GnRH (gonadotropin-releasing hormone), mammalian GnRH (mGnRH) and chicken GnRH-II (cGnRH-II). In this study, we compared the distribution of immunoreactive (ir) mGnRH and cGnRH-II in the brain of immature Siberian sturgeons (Acipenser baeri). The overall distribution of mGnRH was very similar to the distribution of sGnRH in teleosts such as salmonids or cyprinids. mGnRH-ir perikarya were observed in the olfactory nerves and bulbs the telencephalon, the preoptic region, and the mediobasal hypothalamus. All these cell bodies are located along a continuum of ir-fibers that could be traced from the olfactory nerve to the hypothalamopituitary interface. No ir-fibers were observed in the anterior lobe of the pituitary, but a few were seen to enter the neurointermediate lobe. mGnRH-ir fibers were detected in many parts of the brain, particularly in the forebrain. mGnRH-ir cerebrospinal fluid-contacting cells were observed in the telencephalon, the preoptic region, and the mediobasal hypothalamus. In contrast, cGnRH-II was present mainly in the posterior brain, although a few ir axons were seen in the above-mentioned territories. In particular, cGnRH-II-ir cells bodies, negative for mGnRH, were consistently observed in the nucleus of the medial longitudinal fasciculus of the midbrain tegmentum. The cGnRH-II innervation in the optic tectum, cerebellum, vagal lobe, and medulla oblongata was more abundant than the mGnRH innervation in the same areas. This study provides evidence that the organization of the GnRH systems in a primitive bony fish is highly similar to that reported in teleosts and further documents the differential distribution of two forms of GnRH in the brain of vertebrates.

Much is known about bovine lactoperoxidase but no data are available on its primary structure. In this work its main active fraction was isolated from cow's milk and sequenced using a conventional strategy. A clear similarity was found with human myeloperoxidase, eosinophil peroxidase and thyroperoxidase, the sequences of which were recently elucidated from those of their cDNAs and/or genes. The single peptide chain of bovine lactoperoxidase contains 612 amino acid residues, including 15 half-cystines and 4 or 5 potential N-glycosylation sites. The corresponding peptide segments of human myeloperoxidase, eosinophil peroxidase and thyroperoxidase display 55%, 54% and 45% identity with bovine lactoperoxidase, respectively, with 14 out of the 15 half-cystines present in each of the four enzymes being located in identical positions. The occurrence of an odd number of half-cystines in bovine lactoperoxidase supports the recent finding of a heme thiol released from this enzyme by a reducing agent, suggesting that the heme is bound to the peptide chain via a disulfide linkage, since the absence of free thiol in the enzyme was reported long ago.

Management of nitrogen (N) inputs into agricultural systems is of increasing interest due to the intensive use of synthetic fertilizers in modern cash crop systems, which has caused considerable environmental damage, including nitrate contamination of surface and groundwater, eutrophication of coastal marine areas and emission of greenhouse gases. The use of legumes grown in rotations or intercropping is nowadays regarded as an alternative and sustainable way of introducing N into low-input cropping systems. In order to develop a simple tool to assess biological nitrogen fixation (BNF) by legume pulse and forages within crop rotations, we conducted a systematic literature survey with a quantitative statistical analysis intended to define a robust relationship between measurable variables and N2 fixation. We found highly significant correlations between total N accumulation in shoot matter and fixed N2 in forage (y = 0.79x − 0.49) and grain (y = 0.70x + 1.01) legumes. Accurately estimating the contribution...