Seasonal-like growth and regression of the avian song control system: neural and behavioral plasticity in adult male Gambel's white-crowned sparrows

Birdsong is regulated by a series of discrete brain nuclei known as the song control system. In seasonally-breeding male songbirds, seasonal changes in steroid sex hormones regulate the structure and electrophysiology of song control system neurons, resulting in dramatic changes in singing behavior. Male songbirds can be brought into the laboratory, where circulating levels of steroid hormone and photoperiod can be abruptly manipulated, providing controlled conditions under which rapid “seasonal-like” changes in behavior and morphology can be carefully studied. In this mini-review, we discuss the steroidal and cellular mechanisms underlying seasonal-like growth and regression of the song control system in adult male Gambel’s white-crowned sparrows (Zonotrichia leucophrys gambelii), and its impact on song behavior. Specifically, we discuss recent advances concerning: (1) the role of androgen and estrogen receptors in inducing seasonal-like growth of the song control system; (2) how photoperiod modulates the time course of testosterone-induced growth of the song control system; (3) how bilateral intracerebral infusion of androgen and estrogen receptor antagonists near the song control nucleus HVC prevents seasonal-like increases in song stereotypy but not song rate; and (4) the steroidal and cellular mechanisms that mediate rapid regression of the song control system. Throughout this mini-review we compare data collected from white-crowned sparrows to that from other songbird species. We conclude by outlining avenues of future research.     

Seasonal change in luteinizing hormone subunit mRNA in Japanese quail and effects of short daylength and low temperature

Changes in pituitary mRNA levels of LHbeta-subunit (LHbeta) and glycoprotein hormone alpha-subunit (common alpha) were investigated in male Japanese quail under natural and laboratory conditions to clarify the mechanisms of seasonal regulation of luteinizing hormone (LH) secretion. In Experiment 1, birds were kept in outdoor cages under natural conditions from August for 12 months. Both LHbeta and common alpha mRNA levels decreased rapidly from August to September, and after a period of low levels from October through January, they began to increase in February and continued to increase until July. There were more pronounced seasonal changes in testicular weight and cloacal protrusion width with large decreases from August to September and increases from March to May. In Experiment 2, birds were kept on laboratory conditions and transferred from long to short daylengths at 20 or 9 degrees C and held for 14 days. Although common alpha mRNA levels, plasma LH concentrations, testicular weight, and cloacal protrusion area decreased on short days without low temperatures, levels of LHbeta mRNA did not change. Short daylengths combined with low temperatures induced testicular regression and caused decrease in all the parameters measured. Low temperatures under long days did not induce any change in the parameters significantly. These results suggest that (1) synthesis as well as secretion of LH is regulated seasonally, (2) short daylength does not suppress LH synthesis completely unless combined with low ambient temperature, and (3) the effect of photoperiod on the endocrine system regulating LH secretion is predominant over the effect of ambient temperature but ambient temperature acts as an environmental cue to terminate reproductive activities at late summer to early autumn in Japanese quail.     

护理干预改善过敏性鼻炎季节性发作患者的心理状态的效果研究

【】目的：探讨过敏性鼻炎季节性发作的心理评估及护理干预措施,为临床护理干预方案的实施提供理论依据。方法：选取在我院就诊的过敏性鼻炎季节性发作患者208例,随机分为观察组和对照组各104例。对照组按照耳鼻喉科常规护理方案实施护理干预。观察组成立医疗护理团队,对患者进行心理评估并实施针对性的护理干预措施。采用焦虑自评量表(SAS)和抑郁自评量表(SDS)评估和对比两组患者入院前和出院后1天的心理变化。同时对比两组患者对住院期间的护理质量满意率。结果：观察组干预后的SAS量表得分为(38.04±6.38)分,SDS量表得分为(38.15±6.27)分,均显著低于干预前,且低于对照组干预后(均P＜0.05);观察组对住院期间护理质量满意的满意率为96.15%,对照组对住院期间护理质量满意率为82.69%,观察组对住院期间护理质量的满意率显著高于对照组(P＜0.05)。结论：通过心理评估并制定针对性的护理干预措施,有助于提高临床护理的质量,促进过敏性鼻炎季节性发作患者不良心理状态的改善,提升患者对护理工作的满意度。     

Clinical development of a Vero cell culture-derived seasonal influenza vaccine

Background

Cell culture technologies have the potential to improve the robustness and flexibility of influenza vaccine supply and to substantially shorten manufacturing timelines. We investigated the safety, immunogenicity and efficacy of a Vero cell culture-derived seasonal influenza vaccine and utilized these studies to establish a serological correlate of vaccine protection.

Methods

Two multicenter, randomized, double-blind phase III trials were undertaken in the US during the 2008–2009 Northern hemisphere influenza season, in young (18–49 years) and older (50–64 years and ≥65 years) adult subjects. 7250 young adults were randomized 1:1 to receive either Vero-derived vaccine or placebo. 3210 older adult subjects were randomized 8:1 to receive either Vero-derived vaccine or a licensed egg-derived vaccine. Serum hemagglutination inhibition antibody titers were assessed 21 days post-vaccination. Vaccine efficacy in preventing cell culture-confirmed influenza infection was determined for the young adult population. Local and systemic adverse events were recorded in both studies.

Results

The Vero-derived vaccine was safe and well tolerated in both young and older adults. All US and European immunological licensing thresholds were comfortably met in both populations. Vaccine efficacy in young adults was 79% against A/H1N1 viruses antigenically matching the corresponding vaccine strain and 78.5% for all antigenically matched influenza viruses. A hemagglutination inhibition antibody titer of ≥1:15 provided a reliable correlate of protection for the Vero-derived influenza vaccine, with no additional benefit at titers >1:30. Bridging of the correlate of protection established in the young adult population to the older adult immunogenicity data demonstrated the likely effectiveness of the Vero-derived vaccine in the older adult population.

Conclusions

A Vero cell culture-derived seasonal influenza vaccine is safe, immunogenic and protects against infection with influenza virus. The novel vaccine technology has the potential to make a substantial contribution to improving influenza vaccine supply.

Clinical trial registration

The studies are registered with ClinicalTrials.gov, numbers NCT00566345 and NCT00782431.     

上海市嘉定区病媒生物监测结果分析

目的了解嘉定区病媒生物的种类及其季节消长规律,为预防和控制病媒生物传播疾病的发生和流行提供依据。方法按照《全国病媒生物监测方案(试行)》设置监测点,分别以夹日法、笼诱法、灯诱法和粘捕法调查鼠、蝇、蚊、蜚蠊的种类和密度。结果调查发现嘉定区鼠类1科2属3种,小家鼠为优势鼠种(占69.23%),其次是褐家鼠(占21.15%),鼠密度9月最高;蝇类3科4属4种,家蝇为优势种,占捕获总数的68.49%,7月为全年密度最高峰;蚊虫有2科2属3种,分别为淡色库蚊、三带喙库蚊和中华按蚊,淡色库蚊为优势蚊种(占73.83%),其次为三带喙库蚊(占12.58%)和中华按蚊(占13.59%),8月为全年密度最高峰;蜚蠊有2科2属2种,德国小蠊为优势种(占89.29%),7月为全年密度最高峰。结论嘉定区鼠、蝇、蚊、蜚蠊优势种分别为小家鼠、家蝇、淡色库蚊和德国小蠊,密度高峰鼠类为9月,蚊类为8月,其它病媒生物均为7月。     

天津市东丽区病媒生物密度调查结果与分析

目的了解天津市东丽区病媒生物的种类及其季节消长规律,为控制病媒生物的危害提供科学依据。方法按照全国病媒生物监测方案设置监测点,分别采用夹夜法、诱蚊灯法、笼诱法、粘捕法调查鼠、蚊、蝇、蜚蠊的种类和密度。结果东丽区优势鼠种为褐家鼠,占捕获总数的79.55%,其次为小家鼠,占20.45%;鼠密度最高峰在8月,次高峰为5月;蚊密度不同生境有所不同,以牲畜棚密度最高,为19.52只/(灯·h),由高到低依次为牲畜棚、农户、公园绿地、医院、居民区;家蝇为优势蝇种,占捕获总数的58.40%,棕尾别麻蝇和市蝇分别占20.41%和7.13%;不同生境捕获数量由高到低依次为餐饮业>农贸市场>居民区>绿化带;蜚蠊优势种为德国小蠊,占捕获总数的99.81%,其密度和侵害率均以农贸市场最高,高峰期为9月。结论调查的各监测点中,餐饮业鼠密度较高,蚊类在牲畜棚密度最高,蝇类在农贸市场密度最高,蜚蠊密度及侵害率均以农贸市场最高,应加强防治。     

2007-2011年湖南省蚊媒传染病与蚊虫密度季节消长相关性分析

目的探索湖南省蚊虫密度季节消长和流行性乙型脑炎、疟疾和登革热等蚊媒传染病发病的关系。方法收集湖南省2007-2011年疟疾、乙脑和登革热发病资料和蚊虫种群密度季节消长监测资料,用Pearson相关系数法进行分析。结果2007-2011年蚊虫密度与同期蚊媒疾病发病率相关系数r=0．6881,P=0．0134。结论湖南省蚊虫密度季节消长数据与蚊媒病发病率中度相关,反映出蚊虫密度与蚊媒病之间存在复杂联系。     

Melatonin receptor density in Area X of European starlings is correlated with reproductive state and is unaffected by plasma melatonin concentration

Several of the song control nuclei of songbirds, including HVc (higher vocal center) and Area X, contain melatonin receptor (MelR). In laboratory-housed male starlings, the densities of MelR in Area X change markedly according to reproductive state. MelR are down-regulated when starlings are photostimulated (in full breeding condition) and are subsequently up-regulated when starlings become photorefractory (reproductively quiescent). However, seasonal regulation of MelR densities in Area X has only been investigated during the light phase of the light:dark cycle. Variation in MelR densities are physiologically relevant only if they also occur during the dark phase, when melatonin is present in the circulation. Brains from male starlings that were in different reproductive states but exposed to the same 18L:6D photoperiod were collected during either the mid-point of the light phase or the dark phase. Melatonin receptor distribution was assessed in vitro by 125Iodomelatonin (IMEL) receptor autoradiography. All photostimulated birds exhibited down-regulation of MelR in Area X, and all photorefractory birds exhibited high MelR density in Area X, regardless of time of sampling or plasma melatonin concentration. Thus, within each reproductive state, MelR density in Area X did not differ over the course of a circadian cycle. The functional significance of seasonal regulation of MelR in this song control nucleus remains unclear, but it is likely to involve a release of cellular inhibition by melatonin during photostimulation, with possible consequences for song learning, memory consolidation or regulation of the context of song production.     

Photoperiodic induced changes in reproductive state of border canaries (Serinus canaria) are associated with marked variation in hypothalamic gonadotropin-releasing hormone immunoreactivity and the volume of song control regions

In temperate zone songbirds, such as canaries (Serinus canaria), seasonal variation in gonadal activity and behavior are associated with marked brain changes. These include gonadotropin-releasing hormone (GnRH) expression and the volume of brain areas controlling song production. Questions have been raised about the consistency of seasonal brain changes in canaries. Laboratory studies of the American singer strain raised doubts as to whether this strain exhibits a robust photoperiodic response along with changes in brain GnRH content, and studies of free-living canaries have failed to identify seasonal changes in volume of song control nuclei. We assessed differences in brain GnRH and the song control system associated with photoperiod-induced variation in reproductive state in Border canaries. We found that males and females maintained for 10 weeks on long days (14L:10D) regress their gonads, exhibit a decline in testosterone and initiate molt; a response consistent with the onset of absolute photorefractoriness (i.e., failed to respond to previously stimulating daylengths). All birds regained photosensitivity (i.e., exhibited gonadal response to stimulating daylengths) after experiencing short days (8L:16D) for 6 weeks. Furthermore, comparisons of birds in either a photosensitive, photostimulated, or photorefractory state revealed a marked increase in GnRH protein expression in the photosensitive and photostimulated birds over photorefractory birds. A similar variation was observed in the volume of key forebrain song nuclei. Thus, Border canaries demonstrate measurable neuroplasticity in response to photoperiodic manipulations. These data, along with previous work on other strains of canaries, indicate the presence of intra-specific variation in photoperiodically regulated neuroplasticity.     

季节性流感疫苗对小鼠感染H7N9禽流感病毒的保护效力

目的 评价季节性流感裂解疫苗对流感病毒H7N9的免疫保护效力。方法 用我国2012～2013年度季节性流感裂解疫苗,以腹腔注射方式免疫BALB/c小鼠,并设PBS免疫模型组,末次免疫14 d后以5 LD₅₀ A/Anhui/1（H7N9）进行攻试验。感染后观察记录小鼠临床表现,体重变化,并分别于第2天和第4天每组处死3只小鼠,取肺组织和鼻甲骨测病毒滴度和载量。结果 感染后疫苗与模型组小鼠体重下降明显,疫苗组存活率为10%,模型组全部死亡。感染后第4天疫苗组鼻甲骨滴度显著低于模型组。血凝抑制试验及中和实验表明免疫小鼠血清无中和H7N9病毒抗体。结论 季节性流感疫苗在小鼠中对于H7N9流感病毒感染无明显保护作用。