Bruchpilot promotes active zone assembly, Ca2+ channel clustering, and vesicle release   总被引：1，自引：0，他引：1  

Kittel RJ  Wichmann C  Rasse TM  Fouquet W  Schmidt M  Schmid A  Wagh DA  Pawlu C  Kellner RR  Willig KI  Hell SW  Buchner E  Heckmann M  Sigrist SJ 《Science (New York, N.Y.)》2006,312(5776):1051-1054

The molecular organization of presynaptic active zones during calcium influx-triggered neurotransmitter release is the focus of intense investigation. The Drosophila coiled-coil domain protein Bruchpilot (BRP) was observed in donut-shaped structures centered at active zones of neuromuscular synapses by using subdiffraction resolution STED (stimulated emission depletion) fluorescence microscopy. At brp mutant active zones, electron-dense projections (T-bars) were entirely lost, Ca2+ channels were reduced in density, evoked vesicle release was depressed, and short-term plasticity was altered. BRP-like proteins seem to establish proximity between Ca2+ channels and vesicles to allow efficient transmitter release and patterned synaptic plasticity.  相似文献   

Diagnostic imaging: from art to science?     

Schwarz T 《The Journal of small animal practice》2006,47(11):641-642

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Pharmacokinetics of enrofloxacin and its efficacy in comparison with doxycycline in the treatment of Chlamydophila felis infection in cats with conjunctivitis     

Gerhardt N  Schulz BS  Werckenthin C  Hartmann K 《The Veterinary record》2006,159(18):591-594

The concentrations of enrofloxacin were measured in the tears, saliva and serum of 14 cats with signs of upper respiratory tract infection and eight with no signs, after daily doses of 5 mg/kg. Enrofloxacin concentrations above the minimum inhibitory concentration of Chlamydophila felis were found in the saliva and tears of the cats with and without signs of upper respiratory tract infection. In a prospective randomised clinical trial, the efficacy of enrofloxacin against C. felis infection in cats with conjunctivitis was compared with the efficacy of doxycycline. Twenty-five cats were randomly assigned to treatment with either enrofloxacin or doxycycline for 14 days; 15 of the cats tested positive for C. felis by an immunofluorescent antibody test on conjunctival swabs. The two treatment groups showed equal improvements in the clinical signs of conjunctivitis and C. felis infection status; in each group three cats were still C. felis antigen-positive after the 14-day course of treatment, indicating a persistent infection. No side effects were observed in the cats treated with enrofloxacin.  相似文献   

Generation of gut-homing IgA-secreting B cells by intestinal dendritic cells     

Mora JR  Iwata M  Eksteen B  Song SY  Junt T  Senman B  Otipoby KL  Yokota A  Takeuchi H  Ricciardi-Castagnoli P  Rajewsky K  Adams DH  von Andrian UH 《Science (New York, N.Y.)》2006,314(5802):1157-1160

Normal intestinal mucosa contains abundant immunoglobulin A (IgA)-secreting cells, which are generated from B cells in gut-associated lymphoid tissues (GALT). We show that dendritic cells (DC) from GALT induce T cell-independent expression of IgA and gut-homing receptors on B cells. GALT-DC-derived retinoic acid (RA) alone conferred gut tropism but could not promote IgA secretion. However, RA potently synergized with GALT-DC-derived interleukin-6 (IL-6) or IL-5 to induce IgA secretion. Consequently, mice deficient in the RA precursor vitamin A lacked IgA-secreting cells in the small intestine. Thus, GALT-DC shape mucosal immunity by modulating B cell migration and effector activity through synergistically acting mediators.  相似文献   

Rapid chemically induced changes of PtdIns(4,5)P2 gate KCNQ ion channels   总被引：1，自引：0，他引：1  

Suh BC  Inoue T  Meyer T  Hille B 《Science (New York, N.Y.)》2006,314(5804):1454-1457

To resolve the controversy about messengers regulating KCNQ ion channels during phospholipase C-mediated suppression of current, we designed translocatable enzymes that quickly alter the phosphoinositide composition of the plasma membrane after application of a chemical cue. The KCNQ current falls rapidly to zero when phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2 or PI(4,5)P2] is depleted without changing Ca2+, diacylglycerol, or inositol 1,4,5-trisphosphate. Current rises by 30% when PI(4,5)P2 is overproduced and does not change when phosphatidylinositol 3,4,5-trisphosphate is raised. Hence, the depletion of PI(4,5)P2 suffices to suppress current fully, and other second messengers are not needed. Our approach is ideally suited to study biological signaling networks involving membrane phosphoinositides.  相似文献   

The consensus coding sequences of human breast and colorectal cancers     

Sjöblom T  Jones S  Wood LD  Parsons DW  Lin J  Barber TD  Mandelker D  Leary RJ  Ptak J  Silliman N  Szabo S  Buckhaults P  Farrell C  Meeh P  Markowitz SD  Willis J  Dawson D  Willson JK  Gazdar AF  Hartigan J  Wu L  Liu C  Parmigiani G  Park BH  Bachman KE  Papadopoulos N  Vogelstein B  Kinzler KW  Velculescu VE 《Science (New York, N.Y.)》2006,314(5797):268-274

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Hemodynamic effects of methylprednisolone acetate administration in cats     

Ployngam T  Tobias AH  Smith SA  Torres SM  Ross SJ 《American journal of veterinary research》2006,67(4):583-587

OBJECTIVE: To investigate the mechanisms by which corticosteroid administration may predispose cats to congestive heart failure (CHF). ANIMALS: 12 cats receiving methylprednisolone acetate (MPA) for the treatment of dermatologic disorders. PROCEDURE: The study was conducted as a repeated-measures design. Various baseline variables were measured, after which MPA (5 mg/kg, IM) was administered. The same variables were then measured at 3 to 6 days and at 16 to 24 days after MPA administration. Evaluations included physical examination, systolic blood pressure measurement, hematologic analysis, serum biochemical analysis, thoracic radiography, echocardiography, and total body water and plasma volume determination. RESULTS: MPA resulted in a substantial increase in serum glucose concentration at 3 to 6 days after administration. Concurrently, RBC count, Hct, and hemoglobin concentration as well as serum concentrations of the major extracellular electrolytes, sodium and chloride, decreased. Plasma volume increased by 13.4% (> 40% in 3 cats), whereas total body water and body weight slightly decreased. All variables returned to baseline by 16 to 24 days after MPA administration. CONCLUSIONS AND CLINICAL RELEVANCE: These data suggest that MPA administration in cats causes plasma volume expansion as a result of an intra to extracellular fluid shift secondary to glucocorticoid-mediated extracellular hyperglycemia. This mechanism is analogous to the plasma volume expansion that accompanies uncontrolled diabetes mellitus in humans. Any cardiovascular disorders that impair the normal compensatory mechanisms for increased plasma volume may predispose cats to CHF following MPA administration.  相似文献   

The 2006 American Association of Feline Practitioners Feline Vaccine Advisory Panel report     

Richards JR  Elston TH  Ford RB  Gaskell RM  Hartmann K  Hurley KF  Lappin MR  Levy JK  Rodan I  Scherk M  Schultz RD  Sparkes AH 《Journal of the American Veterinary Medical Association》2006,229(9):1405-1441

Vaccination is a medical procedure, and the decision to vaccinate should be based on a risk-based assessment for each cat and each vaccine.  相似文献   

GFAJ-1 is an arsenate-resistant, phosphate-dependent organism     

TJ Erb  P Kiefer  B Hattendorf  D Günther  JA Vorholt 《Science (New York, N.Y.)》2012,337(6093):467-470

The bacterial isolate GFAJ-1 has been proposed to substitute arsenic for phosphorus to sustain growth. We have shown that GFAJ-1 is able to grow at low phosphate concentrations (1.7 μM), even in the presence of high concentrations of arsenate (40 mM), but lacks the ability to grow in phosphorus-depleted (<0.3 μM), arsenate-containing medium. High-resolution mass spectrometry analyses revealed that phosphorylated central metabolites and phosphorylated nucleic acids predominated. A few arsenylated compounds, including C6 sugar arsenates, were detected in extracts of GFAJ-1, when GFAJ-1 was incubated with arsenate, but further experiments showed they formed abiotically. Inductively coupled plasma mass spectrometry confirmed the presence of phosphorus in nucleic acid extracts, while arsenic could not be detected and was below 1 per mil relative to phosphorus. Taken together, we conclude that GFAJ-1 is an arsenate-resistant, but still a phosphate-dependent, bacterium.  相似文献   

Pericardial effusion in a cat with feline infectious peritonitis     

Fischer Y  Wess G  Hartmann K 《Schweizer Archiv für Tierheilkunde》2012,154(1):27-31

This case report describes the disease progression of a male cat with pericardial effusion. Clinical signs (dyspnea, lethargy, and weakness) started very acutely. The initial laboratory profile showed only an increase in alanine aminotransferase enzyme activity. Diagnostic imaging revealed pericardial effusion. Effusion analysis showed a Rivalta-positive, modified transudate. Detection of feline coronavirus antigen in macrophages was negative. General condition and laboratory parameters dramatically worsened within seven days. Therefore, the owners decided to euthanize the cat. Even if effusion variables are macroscopically and microscopically suspicious for FIP, a definitive diagnosis of FIP could only be made by histology (including immunhistochemical staining).  相似文献