This study analyzes data from 19 countries (from April 2009 to Jan 2010), comprising some 70,000 hospitalized patients with severe H1N1 infection, to reveal risk factors for severe pandemic influenza, which include chronic illness, cardiac disease, chronic respiratory disease, and diabetes.

SFTS has been endemic to Japan, and SFTSV has been circulating naturally within the country.

Water transport in highly water-permeable membranes is conducted by water-selective pores-namely, water channels. The recent cloning of water channels revealed the water-selective characteristics of these proteins when expressed in Xenopus oocytes or reconstituted in liposomes. Currently, It is as d that the function of water ch ls is to transport only water. We now report the cloning of a member of the water channel that also transports nonionic small molecules such as urea and glycerol. We named this channel aquaporin 3 (AQP3) for its predominant water permeabilit. AQP3 has amino acid sequence Identity with major intrinsic protein (MIP) family proteins including AQPchannel-forming integral membrane protein, AQP-colecting duct, MIP, AQP-ytonoplast intrinsic protein, nodulin 26, and glycerol facilitator (33-42%). Thus, AQP3 is an additional member of the MEP family. Osmotic water permeability of Xenopus oocytes measured by videomicroscopy was 10-fold higher in oocytes injected with AQP3 transcript than with water-injected oocytes. The increase in osmotic water permeability was inhibited by HgC12, and this effect was reversed by a reducing agent, 2-mercaptoethanol. Although to a smaller degree, AQP3 also facilitated the transport of nonionic small solutes such as urea and glycerol, while the previously cloned water channels are permeable only to water when expressed in Xenopus oocytes. AQP3 mRNA was expressed abundantly in kidney medulla and colon. In kidney, it was exclusively immunokoalzed at the baolateral membrane of collecting duct cells. AQP3 may functon as a water and urea exit hanism in antidlure in ollecting duct cells.Water channels have been postulated for the pathway of selective water permeation in highly water-permeable membranes. Recent

The algal pyrenoid is a large plastid body, where the majority of the CO 2 -fixing enzyme, ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) resides, and it is proposed to be the hub of the algal CO 2 -concentrating mechanism (CCM) and CO 2 fixation. The thylakoid membrane is often in close proximity to or penetrates the pyrenoid itself, implying there is a functional cooperation between the pyrenoid and thylakoid. Here, GFP tagging and immunolocalization analyses revealed that a previously unidentified protein, Pt43233, is targeted to the lumen of the pyrenoid-penetrating thylakoid in the marine diatom Phaeodactylum tricornutum. The recombinant Pt43233 produced in Escherichia coli cells had both carbonic anhydrase (CA) and esterase activities. Furthermore, a Pt43233:GFP-fusion protein immunoprecipitated from P. tricornutum cells displayed a greater specific CA activity than detected for the purified recombinant protein. In an RNAi-generated Pt43233 knockdown mutant grown in atmospheric CO 2 levels, photosynthetic dissolved inorganic carbon (DIC) affinity was decreased and growth was constantly retarded; in contrast, overexpression of Pt43233:GFP yielded a slightly greater photosynthetic DIC affinity. The discovery of a θ-type CA localized to the thylakoid lumen, with an essential role in photosynthetic efficiency and growth, strongly suggests the existence of a common role for the thylakoid-luminal CA with respect to the function of diverse algal pyrenoids. marine diatom | CGHR domain | luminal carbonic anhydrase | CO 2 -concentrating mechanism | pyrenoid M arine diatoms are major primary producers, which are responsible for up to 20% of annual global carbon fixation (1, 2). To overcome the difficulties of CO 2 limitation in alkaline and high-salinity seawater, diatoms use a CO 2 -concentrating mechanism (CCM) for the intracellular accumulation of dissolved inorganic carbon (DIC) (3). It is known that the marine pennate diatom, Phaeodactylum tricornutum, uses solute carrier 4 (SLC4) family transporters to take up HCO 3 − actively from the surrounding seawater (4). Based upon physiological measurements of cellular DIC flux, it has been hypothesized that accumulated HCO 3 − is further concentrated in the chloroplast and that an ample flux of CO 2 to ribulose-1,5-bisphosphate carboxylase/ oxygenase (RubisCO) is facilitated by the pyrenoidal β-carbonic anhydrases (CAs), PtCA1 and PtCA2 (5, 6). In this process, α-type CAs present in the matrices of the four-layered chloroplast membranes are thought to prevent leakage of CO 2 from the chloroplast in P. tricornutum (7,8).Algal CCMs are distinct from their carboxysomal counterparts in cyanobacteria, and were most likely acquired by an extensive convergent evolution process (9). It is postulated that the algal CCM is composed of active DIC transport systems at the plasma membrane and the chloroplast envelope, as well as a highly localized CO 2 formation system within close proximity to RubisCO. The possibility remains that the latter process occurs within the py...

Photosynthesis in marine diatoms is a vital fraction of global primary production empowered by CO 2 -concentrating mechanisms. Acquisition of HCO 3− from seawater is a critical primary step of the CO 2 -concentrating mechanism, allowing marine photoautotrophic eukaryotes to overcome CO 2 limitation in alkaline high-salinity water. However, little is known about molecular mechanisms governing this process. Here, we show the importance of a plasma membrane-type HCO 3 − transporter for CO 2 acquisition in a marine diatom. Ten putative solute carrier (SLC) family HCO 3 − transporter genes were found in the genome of the marine pennate diatom Phaeodactylum tricornutum. Homologs also exist in marine centric species, Thalassiosira pseudonana, suggesting a general occurrence of SLC transporters in marine diatoms. Seven genes were found to encode putative mammalian-type SLC4 family transporters in P. tricornutum, and three of seven genes were specifically transcribed under low CO 2 conditions. One of these gene products, PtSLC4-2, was localized at the plasmalemma and significantly stimulated both dissolved inorganic carbon (DIC) uptake and photosynthesis in P. tricornutum. DIC uptake by PtSLC4-2 was efficiently inhibited by an anion-exchanger inhibitor, 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid, in a concentration-dependent manner and highly dependent on Na + ions at concentrations over 100 mM. These results show that DIC influx into marine diatoms is directly driven at the plasmalemma by a specific HCO 3 − transporter with a significant halophilic nature.bicarbonate transporter | chromista | marine environment | sodium-dependent I norganic carbon entry into algal cells is the primary limiting factor for photosynthesis and requires specific transporters (1). The problem is exacerbated especially in marine environment. Specifically, dissolved CO 2 concentrations are low, and the rate of spontaneous CO 2 formation from HCO 3 − is much slower in the ocean relative to freshwater because of the high alkalinity and salinity of seawater (2). Marine diatoms are responsible for one-fifth of global primary productivity and play a key role in global cycles of carbon and other elements (3, 4). The concentration of dissolved CO 2 in seawater under the present atmospheric pCO 2 (below 15 μM at 20°C) is much lower than the K m [CO 2 ] of ribulose-1,5-bisphosphate carboxylase/oxygenase in diatom species (5). Marine diatoms are, thus, believed to rely directly or indirectly on the use of abundant levels of seawater HCO 3 − to support their primary production. The CO 2 -concentrating mechanism (CCM) has been studied extensively in cyanobacteria, and molecular characterizations have revealed a set of CCM components that completely account for the strategy of cyanobacterial tolerance of CO 2 limitation. Freshwater β-cyanobacteria possess three plasma membrane HCO 3