Increased susceptibility of Trypanosoma lewisi infected, or decomplemented rats to Salmonella typhimurium.

Rats infected with Trypanosoma lewisi or decomplemented by injection of cobra venom factor or complement activating factor of trypanosomes were found to be more susceptible to infection with Salmonella typhimurium. Decomplemented rats subsequently infected with T. lewisi developed higher blood parasitemia than did normal T. lewisi infected rats.     

Isolation of cDNA clones encoding T cell-specific membrane-associated proteins

Of 10 distinct cloned DNA copies of mRNAs expressed in T lymphocytes but not in B lymphocytes and associated with membrane-bound polysomes, one hybridizes to a region of the genome that has rearranged in a T-cell lymphoma and several T-cell hybridomas. These characteristics suggest that it encodes one chain of the elusive antigen receptor on the surface of T lymphocytes.     

N″-cyano-N-4-pyridyl-N′-1,2,2-trimethylpropylguanidine,monohydrate (P 1134): A new,potent vasodilator

Summary N-cyano-N-4-pyridyl-N-1,2,2-trimethylpropylguanidine, monohydrate (P 1134) is a new agent which induces a marked and sustained hypotensive response in normotensive and renal, neurogenic, and spontaneously hypertensive rats, as well as in normotensive and renal hypertensive dogs. The overall potency of this compound is 2–3 times greater than that of hydralazine. The fall of blood pressure is accompanied by an increase in heart rate and cardiac output and a decrease in total peripheral resistance. The hypotensive effect appears to be due primarily to a direct relaxant effect on vascular smooth muscle.Acknowledgment. The helpful comments and advice of Dr W.O. Godtfredsen are greatefully acknowledged.     

Rapid gating and anion permeability of an intracellular aquaporin

Aquaporin (AQP) water-channel proteins are freely permeated by water but not by ions or charged solutes. Although mammalian aquaporins were believed to be located in plasma membranes, rat AQP6 is restricted to intracellular vesicles in renal epithelia. Here we show that AQP6 is functionally distinct from other known aquaporins. When expressed in Xenopus laevis oocytes, AQP6 exhibits low basal water permeability; however, when treated with the known water channel inhibitor, Hg2+, the water permeability of AQP6 oocytes rapidly rises up to tenfold and is accompanied by ion conductance. AQP6 colocalizes with H+-ATPase in intracellular vesicles of acid-secreting alpha-intercalated cells in renal collecting duct. At pH less than 5.5, anion conductance is rapidly and reversibly activated in AQP6 oocytes. Site-directed mutation of lysine to glutamate at position 72 in the cytoplasmic mouth of the pore changes the cation/anion selectivity, but leaves low pH activation intact. Our results demonstrate unusual biophysical properties of an aquaporin, and indicate that anion-channel function may now be explored in a protein with known structure.     

Computer-Aided Detection System on Tangled Roller

Introduction Intheposttreatmentofchoppedfibreproduction,the thirddraftingrollerandtensionheat settingrolleroftenwere tangledbybrokentowforthereasonofhighspeed,hightemperatureofrollersurface,orotheradditionalforeign factors.While,thetworollerswerekeysegmentinthewhole technology.Itwouldleadtooneormoredrumcavedin,and eventobediscardediftheequipmenthadnotbeenstoppedintime.Usually,suchaccidentwouldbringgreatloss,what wouldnotbegotback.Sothetotalsetofequipmentrequiredthatdetectormusthavegoodperfo…