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Eine Mo2S3‐Monolage kann auf einer Kupfer(111)‐Oberfläche in Coexistenz mit dreieckigen MoS2‐Inseln und ‐Monolagen gezüchtet werden. Rastertunnelmikroskopie zeigt, dass Anthrachinon bevorzugt auf der Mo2S3‐Monolage adsorbiert und eine komprimierte Adsorbatlage bildet, bevor es andere Oberflächenbereiche, inklusive der reaktiven Randbereiche der MoS2‐Inseln, besetzt.

The human homologue of yeast Rrn3, a 72-kDa protein, is essential for ribosomal DNA (rDNA) transcription. Although the importance of Rrn3 function in rDNA transcription is well established, its mechanism of action has not been determined. It has been suggested that the phosphorylation of either yeast RNA polymerase I or mammalian Rrn3 regulates the formation of RNA polymerase I⅐Rrn3 complexes that can interact with the committed template. These and other reported differences would have implications with respect to the mechanism by which Rrn3 functions in transcription. For example, in the yeast rDNA transcription system, Rrn3 might function catalytically, but in the mammalian system it might function stoichiometrically. Thus, we examined the question as to whether Rrn3 functions catalytically or stoichiometrically. We report that mammalian Rrn3 becomes the limiting factor as transcription reactions proceed. Moreover, we demonstrate that Rrn3 is inactivated during the transcription reactions. For example, Rrn3 isolated from a reaction that had undergone transcription cannot activate transcription in a subsequent reaction. We also show that this inactivated Rrn3 not only dissociates from RNA polymerase I, but is not capable of forming a stable complex with RNA polymerase I. Our results indicate that Rrn3 functions stoichiometrically in rDNA transcription and that its ability to associate with RNA polymerase I is lost upon transcription.

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Cardiopulmonary resuscitation (CPR) is routinely performed on patients who develop cardiopulmonary arrest in the hospital. In some situations, it is performed on terminally or critically ill patients where death is predicted to be inevitable despite CPR. Since prior consent is not required for this procedure, CPR may be performed without patient consent or foreknowledge. Many of these patients may not want CPR if the anticipated outcome is reviewed with them. This study investigated the frequency of occurrence of a CPR discussion at the time of hospital admission for patients who undergo CPR during hospitalization. Results showed that CPR is infrequently addressed in the hospital orders or medical records in patients who undergo CPR during their hospital stay. In addition, the severity of illness at the time of admission does not appear to influence whether physicians discuss CPR with patients and their families.

To the Editor: Angiotropic lymphoma is an intravascular large cell lymphoma [1]. Although fever is a common manifestation of this disease, it is extremely rare for it to be initially seen as fever of unknown origin (FUO) [2]. A 67-year-old white woman was admitted with a 3-week history of nausea, vomiting, and diarrhea. She was not aware of fever before her admission and denied weight loss or cutaneous lesions. Her physical examination was notable only for a pulse of 107/min and dry mucous membranes. There were no cutaneous lesions, lymphadenopathy, or organomegaly. Initial laboratory investigations revealed a hemoglobin of 7.1 g/dL, hematocrit of 20.8%, platelet count of 368,000/L, and a white blood cell count of 6,800/L (differential WBC: 70% neutrophils, 13% lymphocytes, and 15% monocytes). While the patient was hospitalized, repeated episodes of fever up to 103°F were noted. An extensive workup for FUO, including repeated blood and urine cultures, chest x-ray, duplex scan of the lower extremities, and computed tomography scans of the chest, abdomen, and pelvis, was unrevealing. During the third week of hospitalization, a serum immunofixation study revealed the presence of a low-level IgG kappa monoclonal protein. Because of this finding, a punch biopsy of clinically normal abdominal skin and subcutaneous tissue was obtained to look for amyloidosis. The biopsy specimen revealed neoplastic cells filling the lumens of multiple small blood vessels in the dermis and subcutaneous tissue. Immunoperoxidase stains using antibodies to CD3, CD20, and CD79a revealed the cells to be CD20+, large neoplastic B cells indicative of angiotropic lymphoma (Fig. 1). Shortly after the skin biopsy was performed, the patient's condition worsened, and she died.

Percutaneous transluminal coronary angioplasty (PTCA), when performed early after clinically failed thrombolysis, improves acute infarct-artery patency in up to 90% of cases. Limited data are available regarding the role of rescue stenting in this setting. From January 1995 to December 1999, the authors studied all consecutive patients treated with rescue PTCA or rescue stenting within 12 hours of onset of chest pain and clinically failed thrombolytic therapy at their institution. Baseline demographic characteristics, infarct-related artery location, lesion class, left ventricular function, and incidence of multivessel disease were similar between groups (23 patients in each group). Preprocedural TIMI flow 0 was more common in PTCA patients (p=0.025). Quantitative coronary analysis revealed similar incidence of calcification, thrombus burden, minimal lumen diameter (MLD), and lesion length between groups. Post-procedural TIMI 3 flow was more common in stent patients; however, this was not statistically significant (p=0.18). Greater final MLD (p<0.001), less residual stenosis (p<0.001), and a trend toward larger reference vessel diameter (p=0.13) were observed in favor of stent patients. At 6-month follow-up, there was no difference in the incidence of death, myocardial infarction, or readmission for unstable angina between groups. More stent patients (60% vs 27%, p=0.06) were angina free as compared to PTCA patients. Despite similar in-hospital clinical outcomes, the study suggests better angiographic results and 6-month orbidity with rescue stenting.

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