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131.
Thrombin-induced platelet microbicidal protein (tPMP-1) is a small, cationic peptide released from rabbit platelets exposed to thrombin in vitro. tPMP-1 is microbicidal against a broad spectrum of bloodstream pathogens, including Staphylococcus aureus. Preliminary evidence suggests that tPMP-1 targets and disrupts the staphylococcal cytoplasmic membrane. However, it is not clear if the cytoplasmic membrane is a direct or indirect target of tPMP-1. Therefore, we assessed the in vitro activity of tPMP-1 versus protoplasts prepared from logarithmic-phase (LOG) or stationary-phase (STAT) cells of the genetically related S. aureus strains 19S and 19R (tPMP-1 susceptible and resistant, respectively). Protoplasts exposed to tPMP-1 (2 microg/ml) for 2 h at 37 degrees C were monitored for lysis (decrease in optical density at 420 nm) and ultrastructural alterations (by transmission electron microscopy [TEM]). Exposure to tPMP-1 resulted in substantial lysis of LOG but not STAT protoplasts of 19S, coinciding with protoplast membrane disruption observed by TEM. Thus, it appears that tPMP-1-induced membrane damage is influenced by the bacterial growth phase but is independent of the staphylococcal cell wall. In contrast to 19S, neither LOG nor STAT protoplasts of 19R were lysed by tPMP-1. tPMP-1-induced membrane damage was further characterized with anionic planar lipid bilayers subjected to various trans-negative voltages. tPMP-1 increased conductance across bilayers at -90 mV but not at -30 mV. Once initiated, a reduction in voltage from -90 to -30 mV diminished conductance magnitude but did not eliminate tPMP-1-mediated membrane permeabilization. Therefore, tPMP-1 appears to directly target the staphylococcal cytoplasmic membrane as a primary event in its mechanism of action. Specifically, tPMP-1 likely leads to staphylococcal death, at least in part by permeabilizing the bacterial membrane in a voltage-dependent manner.  相似文献   
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Light-regulated translation of chloroplast messenger RNAs (mRNAs) requires trans-acting factors that interact with the 5' untranslated region (UTR) of these mRNAs. Chloroplast polyadenylate-binding protein (cPABP) specifically binds to the 5'-UTR of the psbA mRNA and is essential for translation of this mRNA. A protein disulfide isomerase that is localized to the chloroplast and copurifies with cPABP was shown to modulate the binding of cPABP to the 5'-UTR of the psbA mRNA by reversibly changing the redox status of cPABP through redox potential or adenosine 5'-diphosphate-dependent phosphorylation. This mechanism allows for a simple reversible switch regulating gene expression in the chloroplast.  相似文献   
133.
An enforced treatment and institutionalization of psychiatric patients are implying a deep cut in the personal rights and freedom of these people. To prevent an abuse of psychiatry as a federal instrument of power and for the protection of all participants (patients and psychiatry personnel) a strict obeyance of federal rules and regulation required. Following to those aspects it is possible to minimate the uncertainty and retention of non-experienced doctors in psychiatry opposite the classical conflict concerning mental cruelty.  相似文献   
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An obese woman aged 18 years had been suffering for several years from axillary hidradenitis suppurativa. Repeated incision and drainage never gave lasting results and the patient became socially isolated. Hidradenitis suppurativa is a chronic suppurative inflammation of skin areas containing apocrine glands: the skin of the axillae, of the breasts and of the anogenital region. Treatment in the first instance consists of general hygienic measures. Pharmaceuticals used include antibiotics, antiandrogens and oestrogens. Surgery is performed when the condition is at an advanced stage, with cellulitis and scarring; ample excision is necessary to reduce the risk of recurrence. CO2 laser therapy is a new method of treatment that shows good results in incipient and advanced lesions.  相似文献   
137.
Patients (pts) may present for lead extraction with symptomatic or asymptomatic subclavian vein or superior vena cava thrombosis. Replacement of permanent pacemaker leads (PPLs) in these pts may be difficult and may require accessing a new site. We examined the utility of replacing PPLs through completely occluded vessels using extraction sheaths as conduits through the total occlusion. Over six years, a total of 210 atrial and/or ventricular PPLs were extracted from 137 pts. Two pts presented with angiographically documented thrombotic occlusion of the subclavian vein. One additional pt. who had presented with a superior vena cava (SVC) syndrome, had a totally occluded innominate vein and SVC occlusion. Balloon venoplasty was used as an adjunct to dilate the SVC. In all pts, after PPLs were removed via a subclavian extraction sheath through the occluded vessel, the retained sheath was used to place a guide wire, then a peel away dilating sheath, to insert new PPLs, in each case on the side of total venous occlusion. Seven PPLs and two lead fragments were extracted, and five new PPLs replaced, ipsilateral to the venous occlusion. These data show that extraction of PPLs through thrombosed veins may be performed successfully and may not require replacing the leads through a new site. This technique spares the pt the need to access the opposite subclavian vein, and it avoids an excessive number of PPLs in the subclavian vein and SVC. The procedure illustrates an efficient means to reintroduce new PPLs with the potential to reduce associated morbidity, since repeat puncture of the subclavian vein is not required. Safety of the procedure as a whole must be considered with regard to the known risks of lead extraction, some complications of which may be substantial using current techniques.  相似文献   
138.
Married women in Benighat, Nepal stressed old age security and continuity of lineage as prominent reasons for wanting sons. In addition, women clearly desired daughters too--an important finding that is less often stressed. Religious reasons and help with household chores were the most common reasons reported for wanting a daughter. Strong desires for sons could increase fertility in settings where fertility is controlled. Additional desires for daughters could have an additional pronatalist influence. For Benighat we document a pervasive desire for at least two sons and at least one daughter. If realized, these sex composition preferences would increase fertility by 50 per cent. Actual effects are no doubt smaller, but the effects of sex preference on the desire for more children and on contraceptive use are clearly visible.  相似文献   
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Several new genes and markers have recently been identified on the proximal short arm of the human X chromosome in the area of Xp11.23. We had previously generated a YAC contig in this region extending from UBE1 to the OATL1 locus. In this report two polymorphic dinucleotide repeats, DXS6949 and DXS6950, were isolated and characterized from the OATL1 locus. A panel of YAC deletion derivatives from the distal portion of the contig was used in conjunction with the rest of the YAC map to position the new microsatellites and order other markers localizing to this interval. The marker order was determined to be DXS1367-ZNF81-DXS6849-ZNF21-DXS6616-DXS 6950-DXS6949. In the proximal region below OATL1, we have isolated a pair of YACs from the GATA locus, B1026 and C01160. Mapping within these YACs indicates the orientation of DXS1126 and DXS1240, while a cosmid near the OATL1 region reveals the overlap between the YAC contigs from the two loci. This cosmid contains the gene responsible for Wiskott-Aldrich syndrome (WAS) and localizes the disease gene between OATL1 and GATA. These data enable the expansion of the present physical map of the X chromosome from UBE1 to the GATA locus, covering a large portion of the Xp11.23 region. Genetic cross-overs in Xp11.23 support the marker orientation and the position of WAS, contrary to previous reports. With the integration of both physical and genetic maps we have predicted the following marker order: Xpter-UBE1-SYN1/ARAF1/ TIMP1-DXS1367-ZNF81-DXS.6849-ZNF21-DXSy6616++ +-(OATL1, DXS6950-DXS6949)- WAS-(GATA, DXS1126)-DXS1240-Xcen.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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