Anticancer property of Bryophyllum pinnata (Lam.) Oken. leaf on human cervical cancer cells

Background: Bryophyllum pinnata (B. pinnata) is a common medicinal plant used in traditional medicine of India and of other countries for curing various infections, bowel diseases, healing wounds and other ailments. However, its anticancer properties are poorly defined. In view of broad spectrum therapeutic potential of B. pinnata we designed a study to examine anti-cancer and anti-Human Papillomavirus (HPV) activities in its leaf extracts and tried to isolate its active principle. Methods: A chloroform extract derived from a bulk of botanically well-characterized pulverized B. pinnata leaves was separated using column chromatography with step-gradient of petroleum ether and ethyl acetate. Fractions were characterized for phyto-chemical compounds by TLC, HPTLC and NMR and Biological activity of the fractions were examined by MTT-based cell viability assay, Electrophoretic Mobility Shift Assay, Northern blotting and assay of apoptosis related proteins by immunoblotting in human cervical cancer cells. Results: Results showed presence of growth inhibitory activity in the crude leaf extracts with IC50 at 552 mu g/ml which resolved to fraction F4 (Petroleum Ether: Ethyl Acetate:: 50: 50) and showed IC50 at 91 mu g/ml. Investigations of anti-viral activity of the extract and its fraction revealed a specific anti-HPV activity on cervical cancer cells as evidenced by downregulation of constitutively active AP1 specific DNA binding activity and suppression of oncogenic c-Fos and c-Jun expression which was accompanied by inhibition of HPV18 transcription. In addition to inhibiting growth, fraction F4 strongly induced apoptosis as evidenced by an increased expression of the pro-apoptotic protein Bax, suppression of the anti-apoptotic molecules Bcl-2, and activation of caspase-3 and cleavage of PARP-1. Phytochemical analysis of fraction F4 by HPTLC and NMR indicated presence of activity that resembled Bryophyllin A. Conclusions: Our study therefore demonstrates presence of anticancer and anti-HPV an activity in B. pinnata leaves that can be further exploited as a potential anticancer, anti-HPV therapeutic for treatment of HPV infection and cervical cancer.

Methodology for Pavement Design Reliability and Back Analysis Using Markov Chain Monte Carlo Simulation

Given the increasing cost of designing and building new highway pavements, reliability analysis has become vital to ensure that a given pavement performs as expected in the field. Recognizing the importance of failure analysis to safety, reliability, performance, and economy, back analysis has been employed in various engineering applications to evaluate the inherent uncertainties of the design and analysis. The probabilistic back analysis method formulated on Bayes' theorem and solved using the Markov chain Monte Carlo simulation method with a Metropolis-Hastings algorithm has proved to be highly efficient to address this issue. It is also quite flexible and is applicable to any type of prior information. In this paper, this method has been used to back-analyze the parameters that influence the pavement life and to consider the uncertainty of the mechanistic-empirical pavement design model. The load-induced pavement structural responses (e.g., stresses, strains, and deflections) used to predict the pavement life are estimated using the response surface methodology model developed based on the results of linear elastic analysis. The failure criteria adopted for the analysis were based on the factor of safety (FOS), and the study was carried out for different sample sizes and jumping distributions to estimate the most robust posterior statistics. From the posterior statistics of the case considered, it was observed that after approximately 150 million standard axle load repetitions, the mean values of the pavement properties decrease as expected, with a significant decrease in the values of the elastic moduli of the expected layers. An analysis of the posterior statistics indicated that the parameters that contribute significantly to the pavement failure were the moduli of the base and surface layer, which is consistent with the findings from other studies. After the back analysis, the base modulus parameters show a significant decrease of 15.8% and the surface layer modulus a decrease of 3.12% in the mean value. The usefulness of the back analysis methodology is further highlighted by estimating the design parameters for specified values of the factor of safety. The analysis revealed that for the pavement section considered, a reliability of 89% and 94% can be achieved by adopting FOS values of 1.5 and 2, respectively. The methodology proposed can therefore be effectively used to identify the parameters that are critical to pavement failure in the design of pavements for specified levels of reliability. DOI: 10.1061/(ASCE)TE.1943-5436.0000455. (C) 2013 American Society of Civil Engineers.

Antimony-resistant but not antimony-sensitive Leishmania donovani up-regulates host IL-10 to overexpress multidrug-resistant protein 1

The molecular mechanism of antimony-resistant Leishmania donovani ((SbLD)-L-R)-driven up-regulation of IL-10 and multidrug-resistant protein 1 (MDR1) in infected macrophages (M phi s) has been investigated. This study showed that both promastigote and amastigote forms of (SbLD)-L-R, but not the antimony-sensitive form of LD, express a unique glycan with N-acetylgalactosamine as a terminal sugar. Removal of it either by enzyme treatment or by knocking down the relevant enzyme, galactosyltransferase in (SbLD)-L-R (KD (SbLD)-L-R), compromises the ability to induce the above effects. Infection of M phi s with KD (SbLD)-L-R enhanced the sensitivity toward antimonials compared with infection with (SbLD)-L-R, and infection of BALB/c mice with KD (SbLD)-L-R caused significantly less organ parasite burden compared with infection induced by (SbLD)-L-R. The innate immune receptor, Toll-like receptor 2/6 heterodimer, is exploited by (SbLD)-L-R to activate ERK and nuclear translocation of NF-kappa B involving p50/c-Rel leading to IL-10 induction, whereas MDR1 up-regulation is mediated by PI3K/Akt and the JNK pathway. Interestingly both recombinant IL-10 and (SbLD)-L-R up-regulate MDR1 in M. with different time kinetics, where phosphorylation of PI3K was noted at 12 h and 48 h, respectively, but M phi s derived from IL-10(-/-) mice are unable to show MDR1 up-regulation on infection with (SbLD)-L-R. Thus, it is very likely that an IL-10 surge is a prerequisite for MDR1 up-regulation. The transcription factor important for IL-10-driven MDR1 up-regulation is c-Fos/c-Jun and not NF-kappa B, as evident from studies with pharmacological inhibitors and promoter mapping with deletion constructs.

La legítima sucesoria y la atomización de la propiedad rural en la Argentina

Resumen: La propiedad rural en la Argentina ha sufrido un proceso de pulverización ocasionado fundamentalmente por dos fenómenos: la venta de tierras y la división forzosa hereditaria. La excesiva subdivisión de la propiedad generada por las leyes sucesorias modernas ha sido no solo constatada por estudios recientes sino también, más atrás en el tiempo, por el propio autor de esas disposiciones legales, es decir, por Vélez Sársfield. Acercándonos a los ciento cuenta años de la vigencia del Código Civil argentino, se observa en la realidad que la aplicación del sistema sucesorio inalterado por este gran lapso ha conducido a una paulatina desaparición de la mediana propiedad rural y, como contrapartida, a la marcada aparición del minifundio y del latifundio. El autor menciona algunas reformas al Código Civil y algunos institutos creados con posterioridad a su sanción, como la unidad económica, que desafortunadamente no han detenido el proceso de atomización de la propiedad agraria y propone, en cambio, otros que podrían mejorar la situación presente, entre ellos, el aumento de la porción disponible por testamento cuya tendencia se advierte en el derecho comparado. La familia agropecuaria requiere de una propiedad estable con dimensiones suficientes para su sustento y para continuar poblando nuestro inmenso territorio.

Plasticidad postlesional en el sistema visual : estrategias experimentales para su incremento en el adulto

196 p. :il.

Molecular mechanisms of interleukin-2 gene inducibility: developmental control and combinatorial action of transcription factors

Interleukin-2 is one of the lymphokines secreted by T helper type 1 cells upon activation mediated by T-cell receptor (TCR) and accessory molecules. The ability to express IL-2 is correlated with T-lineage commitment and is regulated during T cell development and differentiation. Understanding the molecular mechanism of how IL-2 gene inducibility is controlled at each transition and each differentiation process of T-cell development is to understand one aspect of T-cell development. In the present study, we first attempted to elucidate the molecular basis for the developmental changes of IL-2 gene inducibility. We showed that IL-2 gene inducibility is acquired early in immature CD4- CD8-TCR- thymocytes prior to TCR gene rearrangement. Similar to mature T cells, a complete set of transcription factors can be induced at this early stage to activate IL-2 gene expression. The progression of these cells to cortical CD4^+CD8^+TCR^(1o) cells is accompanied by the loss of IL-2 gene inducibility. We demonstrated that DNA binding activities of two transcription factors AP-1 and NF-AT are reduced in cells at this stage. Further, the loss of factor binding, especially AP-1, is attributable to the reduced ability to activate expression of three potential components of AP-1 and NF-AT, including c-Fos, FosB, and Fra-2. We next examined the interaction of transcription factors and the IL-2 promoter in vivo by using the EL4 T cell line and two non-T cell lines. We showed an all-or-none phenomenon regarding the factor-DNA interaction, i.e., in activated T cells, the IL-2 promoter is occupied by sequence-specific transcription factors when all the transcription factors are available; in resting T cells or non-T cells, no specific protein-DNA interaction is observed when only a subset of factors are present in the nuclei. Purposefully reducing a particular set of factor binding activities in stimulated T cells using pharmacological agents cyclosporin A or forskolin also abolished all interactions. The results suggest that a combinatorial and coordinated protein-DNA interaction is required for IL-2 gene activation. The thymocyte experiments clearly illustrated that multiple transcription factors are regulated during intrathymic T-cell development, and this regulation in tum controls the inducibility of the lineage-specific IL-2 gene. The in vivo study of protein-DNA interaction stressed the combinatorial action of transcription factors to stably occupy the IL-2 promoter and to initiate its transcription, and provided a molecular mechanism for changes in IL-2 gene inducibility in T cells undergoing integration of multiple environmental signals.

Design, synthesis and characterization of sequence-specific DNA-cleaving metalloproteins

This thesis describes research pursued in two areas, both involving the design and synthesis of sequence specific DNA-cleaving proteins. The first involves the use of sequence-specific DNA-cleaving metalloproteins to probe the structure of a protein-DNA complex, and the second seeks to develop cleaving moieties capable of DNA cleavage through the generation of a non-diffusible oxidant under physiological conditions.

Chapter One provides a brief review of the literature concerning sequence-specific DNA-binding proteins. Chapter Two summarizes the results of affinity cleaving experiments using leucine zipper-basic region (bZip) DNA-binding proteins. Specifically, the NH_2-terminal locations of a dimer containing the DNA binding domain of the yeast transcriptional activator GCN4 were mapped on the binding sites 5'-CTGACTAAT-3' and 5'ATGACTCTT- 3' using affinity cleaving. Analysis of the DNA cleavage patterns from Fe•EDTA-GCN4(222-281) and (226-281) dimers reveals that the NH_2-termini are in the major groove nine to ten base pairs apart and symmetrically displaced four to five base pairs from the central C of the recognition site. These data are consistent with structural models put forward for this class of DNA binding proteins. The results of these experiments are evaluated in light of the recently published crystal structure for the GCN4-DNA complex. Preliminary investigations of affinity cleaving proteins based on the DNA-binding domains of the bZip proteins Jun and Fos are also described.

Chapter Three describes experiments demonstrating the simultaneous binding of GCN4(226-281) and 1-Methylimidazole-2-carboxamide-netropsin (2-ImN), a designed synthetic peptide which binds in the minor groove of DNA at 5'-TGACT-3' sites as an antiparallel, side-by-side dimer. Through the use of Fe•EDTA-GCN4(226-281) as a sequence-specific footprinting agent, it is shown that the dimeric protein GCN4(226-281) and the dimeric peptide 2- ImN can simultaneously occupy their common binding site in the major and minor grooves of DNA, respectively. The association constants for 2-ImN in the presence and in the absence of Fe•EDTA-GCN4(226-281) are found to be similar, suggesting that the binding of the two dimers is not cooperative.

Chapter Four describes the synthesis and characterization of PBA-β-OH-His- Hin(139-190), a hybrid protein containing the DNA-binding domain of Hin recombinase and the putative iron-binding and oxygen-activating domain of the antitumor antibiotic bleomycin. This 54-residue protein, comprising residues 139-190 of Hin recombinase with the dipeptide pyrimidoblamic acid-β-hydroxy-L-histidine (PBA-β-OH-His) at the NH2 terminus, was synthesized by solid phase methods. PBA-β-OH-His-Hin(139- 190) binds specifically to DNA at four distinct Hin binding sites with affinities comparable to those of the unmodified Hin(139-190). In the presence of dithiothreitol (DTT), Fe•PB-β-OH-His-Hin(139-190) cleaves DNA with specificity remarkably similar to that of Fe•EDTA-Hin(139-190), although with lower efficiency. Analysis of the cleavage pattern suggests that DNA cleavage is mediated through a diffusible species, in contrast with cleavage by bleomycin, which occurs through a non-diffusible oxidant.

Report of Catch Assessment Survey of Lake Albert – Albert Nile conducted in July 2012

A Catch Assessment Surveys (CAS) with the overall objective of generating information on the fish production and commercial value of the fisheries of Lake Albert and Albert Nile system was implemented by the National Fisheries Resources Research Institute (NAFIRRI) in collaboration with the Department of Fisheries Resources (DFR), Local Government staff (FOs) and BMU members at selected landing sites on Lake Albert (12 landing sites) and Albert Nile (26 landing sites) in July 2012. A total 622 and 313 boat days on Lake Albert and Albert Nile respectively were sampled for a period of 9 days. Results indicate an annual landing of 151,600 and 5,900 tonnes (t) of fish with an estimated beach value of 122.5 and 14 Billion (UShs) from Lake Albert and Albert Nile respectively. Over 80% of the catch from Lake Albert comprised the small pelagic species; Neobola bredoi (Muziri) and Brycinus nurse (Ragoogi) followed by Nile perch (6%). However, due to low market value of the small fishes and the high prices attached to Nile perch for industrial processing and export market, the contribution of the latter to beach value rose to 34% of the total. The contribution of the light fishery based on small pelagic species (B. nurse and N. bredoi) are insignificant on Albert Nile. Even if the small pelagic species may be present in the river system, a light fishery based on these two is yet to be developed. Proportionally, Albert Nile still remain a multispecies fishery with over 20 fish species harvested commercially. Interestingly, the Albert Nile fishery still remains primitive with simple crafts and gears (mainly dugout canoes, traps, and gillnets). This could suggest that the more developed the system becomes the higher the level of transformation in its fisheries leading to simplification, characterized by reduction in multispecies nature and dominance of few species. Illegal gears especially undersized gillnet of mesh size less than 4 inches were the most dominant in the Lake Albert and Albert Nile fisheries. They captured large quantities of immature fish particularly when used to target Nile perch, Bagrus, Nile tilapia, and large Barbus spp. Their impact when used to target the smaller species (Ragoogi, Angara & Ngasia) is yet to be evaluated. A specific study to analyze selectivity and impacts of these nets is a recommended. However, the dominance of 1.5” mesh sizes especially on Albert Nile to target Angara, Ngassia and Barbus, is definitely destructive to their fisheries and should be checked forthwith. In addition, there is an emerging fishing method locally referred to as “Salsio or Luzira” whereby fishers stay on the lake from 3 days up to 2 weeks without returning to the landing site. They carry with them food and salt for processing the catches on the lake, and in the case of Albert Nile on make shift shelters on islands and in the game park. They normally use gillnets of 3-3½ inch mesh size and caught mainly Nile perch & Bagrus (Pethi & Munama). On return they land several tons of fish. Most of these Catches are not captured in the estimates presented in our analyses since we target daily fishing boats. The possible impacts of this fishing method should be studied and appropriate action recommended.

饲养层FGF2表达量对猕猴胚胎干细胞自我更新及多能性的影响

用转基因和RNA干扰(RNAi)法建立5组不同成纤维细胞生长因子-2(fibroblast growth factor-2,FGF2)表达量的猕猴耳部皮肤成纤维细胞(MESF)系:过表达FGF2组(f1),过表达的阴性对照组(f2),FGF2 RNA干扰组(f3),RNA干扰的阴性对照组(f4)和未作任何处理的对照组(f5).5组MESF的FGF2表达量相对值为f1:f2:f3:f4:f5=4:2:1:2:2;c-fos,TGF-β1,INHBA,Gremlinl在f1中表达量上升,在f3中表达量下降;BMP4,TGF-β2在f1中表达量下降,在f3中表达量上升;表明内源FGF2能够作用于MESF的TGF-β信号通路,引起相关基因表达量的变化.用这砦细胞作为饲养层长期培养(10代)猕猴胚胎干细胞(RhESC),结果在f1上培养的RhESC增殖速度都比对照组快,并且c-fos,TGF-β1,INHBA,Gremlinl,Oct-4,Nanog,Sox2表达量均上升,BMP4表达下调;在f3上培养的RhESC增殖较慢,BMP4表达上调,c-fos,TGF-β1,INHBA,Gremlinl,Oct-4,Nanog,Sox2表达下调.5组MESF上培养的RhESC形成的EB均表达各胚层早期标记基因(marker),说明RhESC的多能性没有受到影响,但表达量有差异,f1上RhESC形成的EB所有marker都低表达.结果表明饲养层的FGF2含量不仅影响自身相关基凶的表达,还对RhESC的自我更新有一定的作用.

不同FGF-2表达量的饲养层对猕猴和兔胚胎干细胞的增殖和自我更新的影响

胚胎干细胞（ESC）培养是ESC研究的基础，饲养层的选择是ESC培养的一个重要方面。本实验曾对不同的猕猴饲养层进行研究，显示能够更好的支持猕猴ESC生长的饲养层FGF-2表达量也较高。FGF-2，又名bFGF（碱性成纤维生长因子），是ESC生长所需的重要因子，但其中的分子机制现在并未完全了解。本文一方面对ESC相关研究进展进行了综述，另一方面对以下内容进行了研究：用转基因和RNA干（RNAi）扰的方法建立不同FGF-2的表达量猕猴耳部皮肤细胞（MESF）系五组：过表达FGF-2（f1），过表达的阴性对照组（f2），FGF-2 RNA干扰组（f3），RNA干扰的阴性对照组（f4）以及未作任何处理的对照组（f5），这五组MESF的FGF-2表达量相对值为f1：f2：f3：f4：f5＝4：2：1：2：2；c-fos，TGF-β1，INHBA，Gremlin1在f1中表达量上升，在f3中表达量下降；BMP4，TGF-β2在f1中表达量下降，在f3中表达量上升；表明内源FGF-2能够作用于MESF的TGF-β信号通路，引起相关基因表达量的变化。用这些细胞作为饲养层分别培养两种ESC（猕猴ESC，R366. 4和兔ESC，RFESC） ，连续培养了10代，其中在f1上培养的两种ESC增殖速度都比对照组快，并且c-fos，TGF-β1，INHBA，Gremlin1，OCT-4，Nanog，Sox2表达量均上升，BMP4表达下调；在f3上培养的猕猴ESC增殖较慢，BMP4表达上调，c-fos，TGF-β1，INHBA，Gremlin1，OCT-4，Nanog，Sox2表达下调；f3上的兔ESC没有变化。表明ESC中的TGF-β信号通路也受到调节。五组猕猴和兔的ESC形成的EB均表达各胚层早期标记基因(marker)，但表达量有差异，f1上ESC形成的EB所有marker都低表达。实验结果表明饲养层中的FGF-2含量高低不仅影响自身相关基因的表达，还对ESC的增殖和维持自我更新有一定的作用。

典型人类活动对边坡变形及稳定性的影响研究

China is a mountainous country in which geological hazards occurred frequently, especially in the east of China. Except the geology, topography and extreme climate, the large scale human activities have become a major factor to landslides. Typical human activities which induced landslides are fill, cut and underground mining. On the topic of the deformation mechanism and slope stability, taking three different man-made slopes as examples, deformation mechanism and slope stability were studied by several methods, such as field work, numerical modeling and monitor. The details are as following: (1) The numerical modeling approach advantages over other conventional methods such as limit methods, so the numerical modeling is the major tool in this thesis. So far, there is no uniform failure criterion for numerical simulation. The failure criterion were summarized and analyzed firstly, subsequently the appropriate criterion was determinated. (2) Taking 220kV Yanjin transformation substation fill slope as example, the deformable characteristic, unstable mode and laboratory tests were studied systematically. The results show: the slope deformation was probably caused by a combination effect of unfavorable topographic, geological and hydro geological conditions, and external loading due to filling. It was concluded that the creep deformation of the slope was triggered by external loading applied at the back of the slope. In order to define the calculating parameters, a set of consolidated drained (CD) tests, consolidated undrained (CU) tests, repeated direct shear tests and UCS tests were carried out. The stability of the slope before and after reinforcement was assessed using 3D numerical modeling and shear strength reduction technique. The numerical modeling results showed: the factor of safety (FOS) of the slope was 1.10 in the natural state, and reduced to 1.03 after fill, which was close to the critical state and it caused creeping slip or deformation under rainfall. The failure surface in the slope is in active shear failure, whereas tensile failure occurs at the slope crest. After the site was reinforced with piles, the FOS was 1.27. Therefore, the slope is stable after reinforcement measures were taken. (3) The cut slope stability is a complex problem. Taking the left cut slope of Xiangjiaba as example in this thesis, the deformation and slope stability were studied systematically by numerical modeling and monitor methods. The numerical results show: the displacement is gradually increasing along with the cutting, and the largest displacement is 27.5mm which located at the bench between the elevation 340 and 380. Some failure state units distribute near the undermining part and there is no linked failure state occurred from crest to bottom during cutting. After cutting, some failure units appeared at the ground surface between elevation 340 and 360. The increasing tense stress made the disturbed rock failed. The slope is stable after cutting by the monitor method, such as surface monitor, multipoint displacement meter, inclinometer and anchor cable tensometer. (4) The interaction between underground mining and slope stability is a common situation in mountainous. The slope deformation mechanism induced by underground mining may contributed significantly to slope destabilization. The Mabukan slope in xiangjiaba was analyzed to illustrate this. Failure mechanism and the slope stability were presented by numerical modeling and residual deformation monitor. The results show: the roof deformed to the free face and the floor uplift lightly to the free face. The subsidence basin is formed, but the subsidence and the horizontal movement is small, and there is no failure zone occurred. When the underground mining is going on, the roof deformation, subsidence and the horizontal movements begin increasing. The rock deformation near the free face is larger than the ground surface, and the interaction between these coal seams appeared. There are some tensile failures and shear failures occurred on the roof and floor, and a majority of failure is tensile failure. The roof deformation, subsidence and the horizontal movements increased obviously along with the underground mining. The failure characteristic is shear failure which means the tensile stress transformed to the compressive stress. So the underground mining will induced tensile stress first which lead to structure crack, subsequently the compressive stress appeared which result in slippage. The crest was subjected to horizontal tension which made the rock crack along with the joint. The long term residual deformation monitor demonstrates that the slope is stable after the underground mining stopped.

VTA-NAc内orexin A在吗啡和性奖赏相关行为中作用的研究

There are a lot of differences in the neural mechanisms underlying between drug reward and natural reward despite the common neual basis. Undoubtedly, revealing the common and the different mechanisms underlying drug reward and natural reward will promote the development of research on drug addiction. Among diversified natural rewards, sex is often compared to drug because sexual reward has more similarities to drug. The mesolimbic dopamine system (VTA-NAc pathway) is a common pathway activated by natural reinforcers and addictive drugs, mediating reward, emotion and motivation under physiological conditions. The neuroadaptations taking place in the central nervous system including the mesolimbic dopamine system after repeatedly drug taking leads to persistent drug craving, Orexin, a neuropeptide produced in the lateral hypothalamus, plays an important role in reward-associated, motivated behaviors. Orexin neurons have extensive projections to the mesolimbic dopamine system. In order to further investigate the roles of orexin A in drug reward, this study examined the regulatory roles of orexin A in the VTA and NAcSh on drug reinforcement (acqusition of morphine CPP) and drug-seeking behavior (expression of morphine CPP). Moreover, the roles of orexin A on drug reward were compared with sexual reward. The main results are as follows: 1. The expression of morphine CPP was inhibited by intracerebroventricularly (i.c.v.) administered OX1R antagonist SB334867; 2. The male unconditioned sexual motivation was not affected by i.c.v. administered SB334867. However, i.c.v. given orexin A inhibited unconditioned sexual motivation in sexually high-motivated rats but did not affect sexual motivation in low-motivated rats; 3. The acquisition and expression of morphine CPP was inhibited by SB334867 microinjected into the VTA. SB334867 or orexin A injected into the NAcSh did not influence the acquisition of morphine CPP, but orexin A increased the locomotor activity in rats treated with morphine (3mg/kg); 4. SB334867 microinjected into the VTA did not affect male copulatory behavior, neither affect the acqusition of copulatory CPP; 5. The expression of copulatory CPP was associated with increased Fos protein expression in hypothalamic orexin A neurons, and SB334867 microinjected into the VTA inhibited expression of copulatory CPP. These results suggest that, (1) endogenous orexin A is not involved in male unconditioned sexual motivation, but involved in drug craving; (2) orexin A in the VTA instead of in the NAc is involved in drug reinforcement; (3) orexin A in the VTA is critical for drug-seeking behavior, but it is still unclear for the role of orexin A in the NAcSh; (4) in contrast to drug reinforcement, orexin A in the VTA is not involved in reinforcing effect of sexual reward. Orexin A plays a role both in drug-seeking behavior and in sexual reward-seeking behavior, but the different orexin A neuron populations may be responsible for the roles of orexin A in two types of reward. In a word, the differential roles of orexin A in drug and sexual reward are found in the present study, which provides some evidence for further research on the mechanisms of drug addiction.

情绪应激对大鼠体液免疫功能的影响及其机制

This study was undertaken to investigate the effect of emotional stress on humoral immunoactivity and to examine whether the sympathetic nervous system was involved in the immunomodulation. In the present study, two types of emotional stressors were used. One was footshock apparatus used to cause the rats which were given footshock before, emotional stressed; the other was an empty water bottle used to cause the rats which were trained to drink water at two set times each day, emotional stressed. The effect of emotional stress on the primary immune function (anti-ovallum antibody level and spleen index), the endocrine response (corticosterone level, epinephrine and norepinephrine level), the behavioral changes (freezing, defecation, grooming and attacking behavior) were investigated. The main results were: 1. Two types of emotional stress significantly increased the level of plasma corticosterone, norepinephrine and epinephrine, as well as freezing, defecation and attacking behavior. 2. Two types of emotional stress significantly decreased the level of anti-ovallum antibody. A negative correlation between catecholamine level (epinephrine and norepinephrine) and antibody level or spleen index was found. 3. β-adrenergic receptor antagonist propranolol could reverse the immunomodulation induced by emotional stress. 4. After two types of emotional stress, c-fos expression was observed in the following brain areas or nucleus; arcuate nucleus, anterior commissure nucleus, diffuse part of dorsalmedial nucleus hypothalamus, lateral dorsal nucleus thalamus, medial nucleus amygdala, solitary nucleus, frontal cortex and cingulum. These brain areas and nucleus are involved in the central modulation of the autonomic nervous system. Taken together, these findings demonstrate that emotional stress can suppress humoral immunity and the activation of the sympathetic nervous system is involved in the humoral immunomodulation induced by emotional stress.