c-fos基因在乐果中毒后肌无力大鼠肌组织中的表达

采用ＲＴ－ＰＣＲ、ＷｅｓｔｅｒｎＢｌｏｔ技术,检测了有机磷农药乐果对大鼠骨骼肌细胞中即刻早期反应基因ｃ－ｆｏｓ表达的影响。结果表明,在乐果作用下,骨骼肌细胞ｃ－ｆｏｓ基因表达在ｍＲＮＡ以及蛋白质水平均明显增高。然而骨骼肌细胞ｃ－ｆｏｓ的表达是否与毒物刺激有关,其在农药中毒机制上的生物学意义有待深入研究。     

Tonotopic Order in the Adult and Developing Auditory System of the Rat as Shown by c-fos Immunocytochemistry

Immediate éarly genes such as the proto-oncogene c- fos can be expressed in neurons following synaptic excitation by sensory stimulation. C- fos immunocytochemistry has subsequently been shown to be a very sensitive marking technique for neuronal activity. Here, antibodies against the c- fos protein product Fos were used to map the tonotopic organization in the auditory system of adult and developing rats. After stimulating adult rats with pure-tone pulses, bands of Fos-immunoreactive neurons revealed the frequency representation in seven brainstem nuclei: all three subdivisions of the cochlear nucleus, the lateral superior olive, the medial nucleus of the trapezoid body, the ventral nucleus of the trapezoid body, the rostral periolivary nucleus, the dorsal nucleus of the lateral lemniscus and the inferior colliculus. With the exception of the dorsal cochlear nucleus and the inferior colliculus, tonotopicity has not been previously demonstrated in the brainstem nuclei of the rat. During development two striking results were obtained. First, beginning at postnatal day 14 (i.e. ∼2 days after physiological hearing begins in rats), not only low but also high frequencies were able to induce strong Fos immunoreactivity, indicating that gradual recruitment of formerly unresponsive high-frequency sites does not occur in the rat. Second, a gradual age-related shift of the position of isofrequency bands was not seen in any of the nuclei, suggesting that changes in frequency-place code do not occur after 2 weeks postnatally. These results indicate that the rat's auditory brainstem nuclei achieve their adult-like tonotopic organization early on, implying a somewhat different developmental time course than is found in other mammalian species.     

Where is the self? A neuroanatomical theory of consciousness

The enigmatic nature of the experience of self-awareness is examined in the light of recent discoveries and, on this basis, combined with inferences derived introspectively from the experience of the phenomenon itself; a specific physical locus of this experience within the human brains is deduced-proposed. The fundamental premise in this work is that whereever conscious self-awareness is generated, the neuronal structure(s) involved must continually have access to an extremely precise representation of information derived from the sense of vision plus a great variety of other kinds of information so as to permit it to make decisions regarding actions (movements and their implementation) that promote the survival and perpetuation of the biological system in which the self is generated. First, a definitve set of criteria that define most of the inputs to and operations carried out by the self-awareness entity were assembled. This ensemble of functions was then compared with the connections and possible roles of specific neuroanatomical structures described in published literature, particularly the recent literature and particularly that concerned with the sense of vision. It was discovered that only one brain structure receives the prerequisite information from the sense of vision plus information derived from cortical memory stores plus a variety of other relevant sources needed to generate a coherent sense of selfness. This structure is the superior colliculus of the tectum. The superior colliculi not only receive a highly precise retinotopic representation of inputs to the eyes, but also receive inputs from a great variety of other structures, including many areas of the cerebral cortex, vestibular inputs, auditory inputs, "affective" inputs, and inputs that putatively define the positions of the eyes and of the head. This information, it is deduced, not only allows this structure to generate a continuing synthesis of representations of the self-vs.-environment, but also allows a part of it to assess the significance (probable meaning) of these integrated inputs with respect to the selection of an implementation of actions that serve the interests of the physical structure in which the self-experience is generated. The function of memory in this system not only involves the continually updated representation of where the self is with respect to items and objects in its environment, but also provides means through which the relevance of recorded experiences representing the past may be caused to affect the decision-making process.(ABSTRACT TRUNCATED AT 400 WORDS)     

Basal expression of c-Fos and Zif268 in the rat basal ganglia: immunohistochemical characterization of striatal Zif268-positive neurons

Basal expression of the protein products of the inducible immediate early genes (IEGs), c-Fos and Zif268, was investigated in five regions of the rat basal ganglia using immunohistochemistry. In particular, high basal levels of Zif268 but very low levels of c-Fos were seen in the caudate-putamen (CPu). Double immunostaining revealed that many of the constitutively expressed Zif268-positive neurons were GABAergic but very few were cholinergic or neuronal nitric oxide synthase (nNOS)-positive, and some of the Zif268-positive neurons were also immunopositive for a glutamate NMDA receptor subunit NR1 or NR2A. No regional difference between the medial and lateral parts of the CPu was observed in the cellular phenotypes of Zif268-positive neurons. Almost no basal levels of Zif268 were seen in the other four regions: the globus pallidus, entopeduncular nucleus, subthalamic nucleus and substantia nigra pars reticulata. As in the CPu, negligible levels of c-Fos were seen in these four regions. Differential expression of these two IEGs may suggest gene-specific and region-specific functions of c-Fos and Zif268 in the basal ganglia. Constitutive expression of Zif268 existing mainly in the GABAergic neurons in the CPu may at least in part be maintained by glutamatergic afferents.     

即早基因在N-甲基-N-亚硝脲诱导SD大鼠视网膜变性中的表达

目的研究N-甲基-N-亚硝脲(N-m ethyl-N-n itrosourea,MNU)对SD大鼠视网膜毒性的分子机制。方法于♀SD大鼠出生后50 d,一次腹腔注射(ip)MNU 60 mg.kg-1。在MNU处理不同时间后,处死大鼠,取眼球。进行组织学检查;TUNEL试剂盒检测光感受器细胞凋亡;RT-PCR法检测基因c-jun和c-fos的表达。结果MNU作用24 h后,视网膜光感受器外节部定向紊乱;7 d后,外颗粒层和光感受层几乎完全消失。MNU作用12 h后,光感受器细胞开始发生凋亡,24 h达高峰。MNU可时间依赖性地上调即早基因的表达。结论MNU对视网膜的毒性作用是通过增加基因c-jun和c-fos的表达,从而诱导光感受器细胞发生凋亡。     

Development and pretesting of “Becoming Breastfeeding Friendly”: Empowering governments for global scaling up of breastfeeding programmes

Scaling up breastfeeding programmes has not been highly prioritized despite overwhelming evidence that breastfeeding benefits the health of mothers and children. Lack of evidence‐based tools for scaling up may deter countries from prioritizing breastfeeding. To fill this gap, Becoming Breastfeeding Friendly (BBF) was developed to guide countries in effectively scaling up programmes to protect, promote, and support breastfeeding. BBF includes an evidence‐based toolbox that consists of a BBF Index, case studies, and a 5‐meeting process. These three interrelated components enable countries to assess their breastfeeding scaling up environment, identify gaps, propose policy recommendations, develop a scaling up plan, and track progress. The toolbox was developed based on current evidence and expert guidance from a Technical Advisory Group, which was composed of global breastfeeding and metric experts with experience in the scaling up of health and nutrition programmes in low‐, middle‐, and high‐income countries. The BBF toolbox required a step‐by‐step iterative approach to describe and systematize each component, thus an operational manual was developed. The BBF toolbox and BBF operational manual underwent intensive pretesting in two countries, Ghana and Mexico, resulting in the modification of each component plus the operational manual. Pretesting continues in six additional countries demonstrating that BBF is a robust and dynamic multi‐sectoral process that, with relatively minor adaptations, can be successfully implemented in countries across world regions.     

Development of a universal thoracic enhanced recover after surgery protocol for implementation across a diverse multi-hospital health system

BackgroundImplementation of enhanced recovery after surgery (ERAS) pathways for patients undergoing anatomic lung resection have been reported at individual institutions. We hypothesized that an ERAS pathway can be successfully implemented across a large healthcare system including different types of hospital settings (academic, academic-affiliated, community).MethodsAn expert panel with representation from each hospital within a healthcare system was convened to establish a thoracic ERAS pathway for patients undergoing anatomic lung resection and to develop tools and analytics to ensure consistent application. The protocol was translated into an order set and pathway within the electronic health record (EHR). Iterative implementation was performed with recording of the processes involved. Barriers and facilitators to implementation were recorded.ResultsDevelopment and implementation of the protocol took 13 months from conception to rollout. Considerable change management was needed for consensus and incorporation into practice. Facilitators of change included peer accountability, incorporating ERAS care elements into the EHR, and conducting case reviews with timely feedback on protocol deviations. Barriers included institutional cultural differences, agreement in defining mindful deviation from the ERAS protocol, lack of access to specific coded data, and resource scarcity caused by the COVID-19 pandemic. Support from the hospital system’s executive leadership and institutional commitment to quality improvement helped overcome barriers and maintain momentum.ConclusionsDevelopment and implementation of a health-system wide thoracic ERAS protocol for anatomic lung resections across a six-hospital health system requires a multidisciplinary team approach. Barriers can be overcome though multidisciplinary team engagement and executive leadership support.     

探讨引导骨再生技术在即刻种植术中的应用

传统的种植术要求种植体与骨组织之间必须有紧密的接触,这就要求拔牙创必须经过6～12个月的愈合期,充分钙化后才能作为种植床,结果延长了种植治疗疗程,牙槽骨发生了吸收。研究表明,拔牙后2年内牙槽嵴骨质吸收的70％～80％是头3个月发生的,而拔牙后即刻种植,能有效地保持牙槽嵴原有的高度和宽度,防止了牙槽骨的吸收,