Chromosome 7 biclonality in uterine leiomyoma

This study was conducted in adult male Sprague--Dawley rats to determine the distribution of [3H]-nicotine in blood and tissues following a bolus injection and a constant infusion of pure nicotine. The animals were anesthetized and injected with either 0.5 ml of nicotine solution or given a constant infusion of the same nicotine solution with identical amounts of radioactive nicotine. After sacrifice, blood, brain, trachea, salivary gland, esophagus, lung, heart, liver, fundus, antrum, spleen, pancreas, duodenum, jejunum, ileum, cecum, colon, kidneys, adrenal gland, and testes were collected and measured for radioactivity by scintillation counting. The distribution of nicotine was found highest in kidneys by both routes of administration. Higher accumulations were also found in salivary and adrenal glands, fundus, antrum, duodenum, jejunum, ileum and colon. Retention of nicotine via constant infusion was significantly higher in esophagus, fundus antrum, spleen, cecum, pancreas, testes, heart and muscle when compared with bolus injection. Six-fold increase in retention of blood levels of nicotine were found with constant infusion. (P < 0.05). The results indicate that longer retention of nicotine occurs in blood and other specific tissues such as esophagus, fundus, antrum, spleen, cecum, pancreas, testes, heart and muscle via constant exposure. These data may implicate the predisposition of these tissues to pathologic manifestations.     

光影魅力：TCL M530

在追求个性的今天，手机已经成为彰显性格，凸显自身风格的重要饰品，除功能配置外，各手机厂商都非常重视手机的工业设计，国内厂商现在也越来越重视设计的重要性，特别一些大厂，他们在其他行业有着丰富的设计与制造经验，在手机领域，他们从业时间也比较长，经验丰富，对于国内的市场环境也着充分的体会和认识，TCL M530是最近国产手机中一款以设计为重要卖点的产品，它出色地吸取了巧克力系手机的特别，并有所发挥，出色的外形设计给人留下了深刻的印象。[编者按]     

Nf1 regulates hematopoietic progenitor cell growth and ras signaling in response to multiple cytokines

Neurofibromin, the protein encoded by the NF1 tumor-suppressor gene, negatively regulates the output of p21(ras) (Ras) proteins by accelerating the hydrolysis of active Ras-guanosine triphosphate to inactive Ras-guanosine diphosphate. Children with neurofibromatosis type 1 (NF1) are predisposed to juvenile chronic myelogenous leukemia (JCML) and other malignant myeloid disorders, and heterozygous Nf1 knockout mice spontaneously develop a myeloid disorder that resembles JCML. Both human and murine leukemias show loss of the normal allele. JCML cells and Nf1-/- hematopoietic cells isolated from fetal livers selectively form abnormally high numbers of colonies derived from granulocyte-macrophage progenitors in cultures supplemented with low concentrations of granulocyte-macrophage colony stimulating factor (GM-CSF). Taken together, these data suggest that neurofibromin is required to downregulate Ras activation in myeloid cells exposed to GM-CSF. We have investigated the growth and proliferation of purified populations of hematopoietic progenitor cells isolated from Nf1 knockout mice in response to the cytokines interleukin (IL)-3 and stem cell factor (SCF), as well as to GM-CSF. We found abnormal proliferation of both immature and lineage-restricted progenitor populations, and we observed increased synergy between SCF and either IL-3 or GM-CSF in Nf1-/- progenitors. Nf1-/- fetal livers also showed an absolute increase in the numbers of immature progenitors. We further demonstrate constitutive activation of the Ras-Raf-MAP (mitogen-activated protein) kinase signaling pathway in primary c-kit+ Nf1-/- progenitors and hyperactivation of MAP kinase after growth factor stimulation. The results of these experiments in primary hematopoietic cells implicate Nf1 as playing a central role in regulating the proliferation and survival of primitive and lineage-restricted myeloid progenitors in response to multiple cytokines by modulating Ras output.     

Tissue plasminogen activator contributes to the late phase of LTP and to synaptic growth in the hippocampal mossy fiber pathway

The expression of tissue plasminogen activator (tPA) is increased during activity-dependent forms of synaptic plasticity. We have found that inhibitors of tPA inhibit the late phase of long-term potentiation (L-LTP) induced by either forskolin or tetanic stimulation in the hippocampal mossy fiber and Schaffer collateral pathways. Moreover, application of tPA enhances L-LTP induced by a single tetanus. Exposure of granule cells in culture to forskolin results in secretion of tPA, elongation of mossy fiber axons, and formation of new, active presynaptic varicosities contiguous to dendritic clusters of the glutamate receptor R1. These structural changes are blocked by tPA inhibitors and induced by application of tPA. Thus, tPA may be critically involved in the production of L-LTP and specifically in synaptic growth.     

Long-term therapy with the guanine nucleoside analog penciclovir controls chronic duck hepatitis B virus infection in vivo

Ducks congenitally infected with duck hepatitis B virus (DHBV) were treated with the antiviral guanine nucleoside analog penciclovir for 12 or 24 weeks at a dosage of 10 mg/kg of body weight per day. By the completion of both 12 and 24 weeks of therapy, molecular hybridization studies of the liver tissue revealed that the viral DNA, RNA, and protein levels were significantly reduced compared to those in the placebo-treated controls. Penciclovir treatment for 12 or 24 weeks was not associated with any toxicity, establishing the efficacy and safety of long-term penciclovir therapy in chronic DHBV infection.     

Diffusion-weighted imaging in hyperacute stroke--gold standard?

Diffusion-weighted imaging (DWI) is more sensitive than CT and conventional T2-weighted MR imaging in the detection of early cerebral ischemia and infarction. In this case report, we present a case of a 79-year-old woman with symptoms of acute stroke, clinically and radiologically documented progression to complete stroke with an initial negative diffusion-weighted scan.