Simultaneous pressure and 19F NMR pH measurements of smooth muscle cells of intact hog carotid arteries at rest and during contractions with norepinephrine

Using 19F NMR we have measured the intracellular pH of the vascular smooth muscle cells of hog carotid arteries at rest and during contractions induced with norepinephrine. Experiments were performed on single, intact arteries closed at both ends, superfused from the lumen and loaded with the 19F NMR pH indicator alpha-difluoromethylalanine. At rest, luminal pressure was maintained at 100 +/- 2 mm Hg and intracellular pH was 7.12 +/- 0.04. Contractions elicited with 10(-5) M norepinephrine were associated with a pressure increase of 18 +/- 6 mm Hg and a decrease in pH of 0.04 +/- 0.02 units.     

Intercellular communication in the rat anterior pituitary gland: an in vivo and in vitro study

The concept of "stimulus-secretion coupling" suggested by Douglas and co-workers to explain the events related to monamine discharge by the adrenal medulla (5, 7) may be applied to other endocrine tissues, such as adrenal cortex (36), pancreatic islets (4), and magnocellular hypothalamic neurons (6), which exhibit a similar ion-dependent process of hormone elaboration. In addition, they share another feature, that of joining neighbor cells via membrane junctions (12, 26, and Fletcher, unpublished observation). Given this, and the reports that hormone secretion by the pars distalis also involves a secretagogue-induced decrease in membrane bioelectric potential accompanied by a rise in cellular [Ca++] (27, 34, 41), it was appropriate to test the possibility that cells of the anterior pituitary gland are united by junctions.     

U.S. National Institutes of Health Core Consolidation–Investing in Greater Efficiency

The U.S. National Institutes of Health (NIH) invests substantial resources in core research facilities (cores) that support research by providing advanced technologies and scientific and technical expertise as a shared resource. In 2010, the NIH issued an initiative to consolidate multiple core facilities into a single, more efficient core. Twenty-six institutions were awarded supplements to consolidate a number of similar core facilities. Although this approach may not work for all core settings, this effort resulted in consolidated cores that were more efficient and of greater benefit to investigators. The improvements in core operations resulted in both increased services and more core users through installation of advanced instrumentation, access to higher levels of management expertise; integration of information management and data systems; and consolidation of billing; purchasing, scheduling, and tracking services. Cost recovery to support core operations also benefitted from the consolidation effort, in some cases severalfold. In conclusion, this program of core consolidation resulted in improvements in the effective operation of core facilities, benefiting both investigators and their supporting institutions.     

Misexpression screen in Drosophila melanogaster aiming to reveal novel factors involved in formation of body parts

To identify novel factors that lead a fly imaginal disc to adopt its developmental fate, we carried out a modular dominant misexpression screen in imaginal discs. We have identified two factors that appear to change the fate of the respective body structure and appear to lead to the transformation of a body part. In one mutant line, notum tissue, normally derived from wing imaginal tissue, formed close to the site of the sternopleural bristles, which are leg disc derivatives. In the other line, the arista is transformed into a tubular structure, resembling an abnormal leg. We found that ectopic expression of abrupt was responsible for this potential transformation of the arista.     

Natural products as starting points for future anti-malarial therapies: going back to our roots?

Background

Population movements along the Thailand-Cambodia border, particularly among highly mobile and hard-to-access migrant groups from Cambodia and Myanmar, are assumed to play a key role in the spread of artemisinin resistance. Data on treatment-seeking behaviours, knowledge and perceptions about malaria, and use of preventive measures is lacking as characteristics of this population prevent them from being represented in routine surveillance and the lack of a sampling frame makes reliable surveys challenging.

Methods

A survey of migrant populations from Cambodia and Myanmar was implemented in five selected rural locations in Thailand along the Thai-Cambodian border using respondent driven sampling (RDS) to determine demographic characteristics of the population, migratory patterns, knowledge about malaria, and health-care -seeking behaviours.

Results

The majority of migrants from Myanmar are long-term residents (98%) with no plans to move back to Myanmar, understand spoken Thai (77%) and can therefore benefit from health messages in Thai, have Thai health insurance (99%) and accessed public health services in Thailand (63%) for their last illness. In comparison, the majority of Cambodian migrants are short-term (72%). Of the short-term Cambodian migrants, 92% work in agriculture, 18% speak Thai, 3.4% have Thai health insurance, and the majority returned to Cambodia for treatment (45%), self-treated (11%), or did not seek treatment for their last illness (27%).

Conclusion

Most highly mobile migrants along the Thai-Cambodia border are not accessing health messages or health treatment in Thailand, increasing their risk of malaria and facilitating the spread of potentially resistant Plasmodium falciparum as they return to Cambodia to seek treatment. Reaching out to highly mobile migrants with health messaging they can understand and malaria diagnosis and treatment services they can access is imperative in the effort to contain the spread of artemisinin-resistant P. falciparum.     

Airway cellularity, lipid laden macrophages and microbiology of gastric juice and airways in children with reflux oesophagitis

Background and methods

Human metapneumovirus (hMPV) is a recently discovered respiratory virus associated with bronchiolitis, pneumonia, croup and exacerbations of asthma. Since respiratory viruses are frequently detected in patients with acute exacerbations of COPD (AE-COPD) it was our aim to investigate the frequency of hMPV detection in a prospective cohort of hospitalized patients with AE-COPD compared to patients with stable COPD and to smokers without by means of quantitative real-time RT-PCR.

Results

We analysed nasal lavage and induced sputum of 130 patients with AE-COPD, 65 patients with stable COPD and 34 smokers without COPD. HMPV was detected in 3/130 (2.3%) AE-COPD patients with a mean of 6.5 × 10⁵ viral copies/ml in nasal lavage and 1.88 × 10⁵ viral copies/ml in induced sputum. It was not found in patients with stable COPD or smokers without COPD.

Conclusion

HMPV is only found in a very small number of patients with AE-COPD. However it should be considered as a further possible viral trigger of AE-COPD because asymptomatic carriage is unlikely.     

γCOP Is Required for Apical Protein Secretion and Epithelial Morphogenesis in Drosophila melanogaster

Background

There is increasing evidence that tissue-specific modifications of basic cellular functions play an important role in development and disease. To identify the functions of COPI coatomer-mediated membrane trafficking in Drosophila development, we were aiming to create loss-of-function mutations in the γCOP gene, which encodes a subunit of the COPI coatomer complex.

Principal Findings

We found that γCOP is essential for the viability of the Drosophila embryo. In the absence of zygotic γCOP activity, embryos die late in embryogenesis and display pronounced defects in morphogenesis of the embryonic epidermis and of tracheal tubes. The coordinated cell rearrangements and cell shape changes during tracheal tube morphogenesis critically depend on apical secretion of certain proteins. Investigation of tracheal morphogenesis in γCOP loss-of-function mutants revealed that several key proteins required for tracheal morphogenesis are not properly secreted into the apical lumen. As a consequence, γCOP mutants show defects in cell rearrangements during branch elongation, in tube dilation, as well as in tube fusion. We present genetic evidence that a specific subset of the tracheal defects in γCOP mutants is due to the reduced secretion of the Zona Pellucida protein Piopio. Thus, we identified a critical target protein of COPI-dependent secretion in epithelial tube morphogenesis.

Conclusions/Significance

These studies highlight the role of COPI coatomer-mediated vesicle trafficking in both general and tissue-specific secretion in a multicellular organism. Although COPI coatomer is generally required for protein secretion, we show that the phenotypic effect of γCOP mutations is surprisingly specific. Importantly, we attribute a distinct aspect of the γCOP phenotype to the effect on a specific key target protein.     

植物的遗传转化及其应用(英文)

近年来,植物遗传转化研究有了长足的发展。已经达到能够通过简单的遗传控制手段研究具有新表现型的植物,甚至达到进入商业化的程度。这些手段包括植物生物学的主要研究技术以及植物组织培养和树种改良的一些实用方法。尽管采用农瘤杆菌和鸟枪法等技术的植物遗传转化系统已经得到了广泛的应用,但是在如何开发具有能够得到控制表达的转基因高产植物方面,在如何使所得到的转基因植物远离遗传危害等方面,目前的转化系统遇到了极大的技术挑战。已经提出了各种各样的方法用于将新基因稳定地导入120多种不同植物的核基因组。本文将讨论这些遗传转化系统所需的生物学要求和实际应用方面的需求、基因转化和转基因表达的研究策略、遗传转化植物的鉴定以及转基因植物与大众的认可。本文将分为七个部分加以讨论:一、导言;二 、基因转化到细胞里的方法;三、植物遗传转化策略;四、植物遗传转化的鉴定;五、植物遗传转化的实际应用;六、转基因植物与环境;七、未来植物遗传转化的需求与发展方向。     

Spalt major controls the development of the notum and of wing hinge primordia of the Drosophila melanogaster wing imaginal disc

The Drosophila wing and the dorsal thorax develop from primordia within the wing imaginal disc. Here we show that spalt major (salm) is expressed within the presumptive dorsal body wall primordium early in wing disc development to specify notum and wing hinge tissue. Upon ectopic salm expression, dorsally located second leg disc cells develop notum and wing hinge tissue instead of sternopleural tissue. Similarly, by salm over-expression within the wing disc, wing blade formation is suppressed and a mirror-image duplication of the notum and wing hinge is formed. In large dorsal clones, which lack salm and its neighboring paralogue spalt related (salr), the cells of the notum primordium do not grow; these dorsal cells are not specified as notum, hence no notum outgrowth develops. These results suggest that the zinc finger factors encoded by the salm/salr complex play important roles in defining cells of the early wing disc as dorsal body wall cells, which develop into a large dorsal body wall territory and form mesonotum and some wing hinge tissue, and in delimiting the wing primordium. We also find that salm activity is down-regulated by its own product and by that of the Pax gene eyegone.