Symptomatologie und Verlauf der A-Hypervitaminose bei Ratten Infolge Enteraler,Subcutaner und Percutaner Darreichung von Vitamin A-Konzentraten

Ohne ZusammenfassungI. diese Wschr.1938, 777.     

Aggregation of equine platelets by PAF (platelet-activating factor)

Platelet-activating factor (PAF), a lipid released as a result of immediate allergic reactions from basophils and mast cells as well as by a variety of other cell types and stimuli, is one of the most potent platelet agonists and hypotensive agents known. Equine platelets stimulated over a wide range of PAF concentrations aggregated in a time- and dose-dependent manner. Maximum aggregation was observed at concentrations of PAF as low as 3.58×10^?14 M with platelet-rich plasma (PRP) and 3.58×10^?16 M with washed platelets. Furthermore, the aggregation observed did not appear to be breed-dependent. Finally, the platelet arachidonate pathway appeared to play no role in PAF-induced aggregation as exogenous arachidonate did not enhance the reaction, nor were equine platelets pretreated with 38 μM aspirin inhibited in their response to PAF. This level of aspirin totally inhibited the equine platelet aggregation response to arachidonate.     

Angioplasty in ulcerative coronary artery disease: Acute results and early follow-up

The safety and efficacy of percutaneous transluminal coronary angioplasty (PTCA) for stenoses involving ulcerative lesions were retrospectively studied. Seventy-seven patients (62 men and 15 women, mean age 62 ± 10 years) representing 3.4% of 2,250 patients treated with PTCA during the period January 1, 1988 and June 30, 1990, had pre-PTCA stenoses defined as ulcerated. Twenty-eight (36%) of the stenoses were localized in the left anterior descending coronary artery, 9 (12%) in the left circumflex and 40 (52%) in the right coronary artery. During angioplasty, percent diameter stenosis was reduced from 73 ± 14% to 22 ± 13% and transstenotic gradient decreased from 48 ± 18 to 12 ± 6 mm Hg. Clinical success (freedom from angina at discharge without coronary bypass surgery, infarction or death) was achieved in 70 patients (90.9%). There were seven unsuccessful cases: three underwent elective coronary bypass surgery, one was managed medically, and three developed a major flow interrupting dissection during the procedure requiring emergency coronary bypass surgery. There were no deaths. At mean follow-up of 7.6 months, 45 of 61 patients (73.7%) remained asymptomatic. One patient needed an elective coronary bypass surgery and five patients had a successful repeat PTCA. In conclusion, PTCA for an ulcerated stenosis can be performed safely with a high primary success rate and a favorable early clinical course.     

Modulation of Vacuolar pH Is Required for Replication of Edwardsiella ictaluri in Channel Catfish Macrophages

Previous in vitro work demonstrated that Edwardsiella ictaluri produces an acid-activated urease that can modulate environmental pH through the production of ammonia from urea. Additional work revealed that expression of the E. ictaluri type III secretion system (T3SS) is upregulated by acidic pH. Both the urease and the T3SS were previously shown to be essential to intracellular replication. In this work, fluorescence microscopy with LysoTracker Red DND-99 (LTR) indicated that E. ictaluri-containing vacuoles (ECV) became acidified following ingestion by head kidney-derived macrophages (HKDM). In vivo ratiometric imaging demonstrated a lowered ECV pH, which fell to as low as pH 4 but subsequently increased to pH 6 or greater. Inhibition of vacuolar H⁺-ATPases by use of the specific inhibitor bafilomycin A₁ abrogated both ECV acidification and intracellular replication in HKDM. Failure of an E. ictaluri urease knockout mutant to increase the ECV pH in the in vivo ratiometric assay suggests that ammonia produced by the urease reaction mediates the pH increase. Additionally, when the specific arginase inhibitor l-norvaline was used to treat E. ictaluri-infected HKDM, the ECV failed to neutralize and E. ictaluri was unable to replicate. This indicates that the HKDM-encoded arginase enzyme produces the urea used by the E. ictaluri urease enzyme. Failure of the ECV to acidify would prevent both upregulation of the T3SS and activation of the urease enzyme, either of which would prevent E. ictaluri from replicating in HKDM. Failure of the ECV to neutralize would result in a vacuolar pH too low to support E. ictaluri replication.     

Utility of point-of-care biliary ultrasound in the evaluation of emergency patients with isolated acute non-traumatic epigastric pain

To determine the utility of emergency physician-performed point-of-care biliary ultrasound in the evaluation of emergency department (ED) patients with isolated acute non-traumatic epigastric pain. This was a multi-center prospective observational study of adult patients presenting to the ED with isolated acute non-traumatic epigastric pain. Patients with abdominal tenderness at any site other than the epigastric region, or with a history of gall stones, cholecystectomy, gastrointestinal bleeding, chronic abdominal pain, trauma, or altered mental status were excluded. Emergency physician investigators performed point-of-care biliary ultrasound after clinical assessment. Demographic information, history, physical examination findings, laboratory results, additional diagnostic tests, and disposition data were collected. A total of 51 patients (39 women, 12 men) were enrolled. The mean age of the patients was 36.4 years ± 13.6 (SD). All subjects had isolated epigastric tenderness. Gallstones were found in 20/51 (39 %, 95 % CI 26–52 %) on point-of-care biliary ultrasound. Of the 20 patients who had gallstones, eight had sonographic signs of chloecystitis. The treating emergency physicians’ initial evaluation did not plan to include an ultrasound in 17/20 patients with gallstones. 19/20 patients were initially given a GI cocktail by the treating emergency physicians. Point-of-care biliary ultrasound detected gall stones in more than one-third of ED patients with isolated acute non-traumatic epigastric pain. All patients presenting to the ED with non-traumatic epigastric pain should be evaluated for biliary disease with an ultrasound imaging study. Bedside ultrasound can avoid misdiagnosis and expedite management in these patients.     

Sexual Behavior Before and After Pregnancy Detection in Four Microbicide Trials

Vaginal microbicide gel trials for HIV prevention may require withdrawal of study product when a woman becomes pregnant. We assessed the potential impact of withdrawals in four trials by comparing self-reported sexual behavior pre- and post-pregnancy detection: (1) behavior in the month prior to positive pregnancy test versus behavior reported at the subsequent monthly visit; (2) behavior changes according to pregnancy status at the subsequent visit (continuing pregnancy versus not); (3) average sexual behaviors reported for all months prior to pregnancy detection versus all months after pregnancy was no longer detected; and (4) behavior changes among participants never testing positive for pregnancy. Pregnancy detection was associated with immediate reductions in self-reported numbers of partners and sex acts. The proportion of acts in which study gel was used following a negative pregnancy test did not return to pre-pregnancy levels. Pregnancies complicate the conduct and interpretation of vaginal microbicide trials when product must be withdrawn.     

Verbal paired-associate learning by APOE genotype in non-demented older adults: fMRI evidence of a right hemispheric compensatory response

Previous studies of episodic memory report a greater extent of blood-oxygenation-level-dependent (BOLD) response in non-demented older adults with the apolipoprotein E epsilon-4 (APOE epsilon4) allele than in those without the allele. We conducted a functional MRI study to investigate whether APOE genotype is related to brain response to verbal paired-associate encoding and consolidation, particularly in the right hemisphere, among non-demented older adults. Structurally segmented volumes and BOLD response were measured in 13 non-epsilon4 and 12 epsilon4 subjects. The epsilon4 group displayed greater activation than the non-epsilon4 group in multiple right hemisphere regions for previously encoded word pairs relative to fixation. Activation within manually outlined hippocampal regions of interest also displayed genotype-specific dissociations consistent with whole brain analyses. Furthermore, this differential BOLD response occurred in the presence of equivalent behavioral and neuropsychological performances as well as comparable hippocampal and overall structural segmentation volumes between groups. Results implicate a widely distributed and interconnected network of right hemisphere brain regions that may be involved in compensating for APOE epsilon4-related deficiencies associated with verbal episodic memory encoding and consolidation.     

Revision Total Hip Arthroplasty With a Modular Cementless Femoral Stem

We retrospectively reviewed 123 patients who underwent cementless THA with modular femoral stem designs for revision THA or conversion of failed ORIF and found 75 patients available for analysis. The Harris Hip Score (HHS) improved from 52 ± 14 to 86 ± 11 (P < 0.001). The femoral stem was re-revised in eight patients (11%). The mean time to re-revision was 1.1 years (0.13–2.54). Reasons for re-revision included infection (n = 5, 7%), aseptic loosening (n = 2, 3%) and significant pain (n = 1, 1%). There were no failures of the modular junctions. PC stems had an increased rate of intraoperative fractures (PC 28% vs. STS 9%, P = 0.04). Modular cementless femoral stems provide acceptable mid-term results in revision THA.