Properties of neuronal activity related to a visual reaction time task in the monkey prefrontal cortex

1. Quantitative properties of neuronal activity related to a visual reaction time task were studied in the monkey prefrontal cortex. The task consisted of an initial waiting phase (3.0-s period), a warning phase (green lamp, a variable period of 1.5-3.5 s), a go phase (red lamp), and a reward phase. 2. A total of 189 task-related neurons showed 233 changes in discharge rates during the warning (n = 86), GO (n = 103), and reward (n = 44) phases of the task. Most of the task-related neurons (145/189, 77%) showed changes during only one of the task phases, and were designated W (warning phase)-type (n = 42), GO (go phase)-type (n = 59), and RE (reward phase)-type (n = 44) neurons. The remainder (n = 44, 23%) showed changes during both the warning and the go phases, and were designated WG (warning and go phase)-type neurons. In each phase, onset latencies, peak latencies, and decay times of each change were measured and compared. 3. The changes during the warning phase (n = 86) were separated into three groups based on decay time; that is, phasic changes (n = 31), phasic-tonic changes (n = 23), and tonic changes (n = 32). Onset latencies and peak latencies were homogeneously distributed, and there were no clear groupings, although phasic and phasic-tonic changes tended to show shorter latencies than tonic changes. 4. The changes during the go phase (n = 103) did not show distinct differences, either in terms of decay time or of latency. The changes during the go phase showed various degrees of coupling to both the visual go signal (GS) and lever-release hand movement. To quantitate the coupling, a value to indicate the degrees of coupling (coupling index) was calculated. The changes coupled more strongly to the GS (cue coupled), those coupled more closely to the lever release (movement coupled), and intermediate changes could be distinguished from each other. The cue-coupled changes showed shorter latencies from the time onset of the GS than the movement-coupled changes, and the intermediate changes showed intermediate latencies. The decay time and the duration of the intermediate changes were longer than those of the cue-coupled changes and the movement-coupled changes. 5. The properties of WG-type neurons were compared with those of W-type and GO-type neurons.(ABSTRACT TRUNCATED AT 400 WORDS)     

Neuroprotective properties of valproate

Neuropsychiatric disturbances are extremely common in Alzheimer’s disease (AD), and represent integral features of the illness, as well as appropriate targets for therapy. We are interested in designing trials aimed at preventing or delaying the emergence of psychopathology in AD. For symptomatic treatment of agitation, mood stabilizers, particularly sodium valproate, have proved to be beneficial in some patients. Since these effects take several weeks to emerge, we considered that they might be dependent on potentially neuroprotective actions of valproate, such as inhibition of apoptosis and slowing of neurofibrillary tangle formation. In this article we present the rationale for testing the neuroprotective potential of valproate experimentally in mouse models of tauopathy and in a clinical trial of patients with AD who lack psychopathology at baseline. Together, these studies will provide important tests of the hypothesis that valproate, either through inhibition of tau phosphorylation or some other mechanism, is a useful therapeutic agent to modify disease progression in AD.     

阴沟肠杆菌超广谱β—内酰胺酶、诱导酶的检出与耐药相关性的分析

目的：了解阴沟肠杆菌超广谱β－内酰胺酶和诱导酶的产生和分布情况。并分析产酶特性和耐药表型的相关性。方法：用纸片扩散确证法和相邻纸片法对104株阴沟肠杆菌进行超广谱β－内酰胺酶及诱导酶的检测，用VITEK全自动药敏分析系统和K－B琼脂扩散法检测其对20种抗生素的耐药性。结果：104例阴沟肠杆菌中，检出超广谱β－内酰胺酶阳性株77株，占74％，诱导酶阳性株26株，占25％，13株两种酶同时阳性。超广谱β－内酰胺酶阳性株主要集中在几个病区，诱导酶阳性株则无此倾向，104株菌对多种怀素高度耐药，产超广谱β－内酰胺酶株的耐药率明显高于非产酶株，产诱导酶株的耐药率反而低于非产酶株。结论：阴沟肠杆菌产酶情况和耐药性均十分严重。多重耐药的主要原因是由于菌株产生超广谱β－内酰胺酶，产酶株对三代头孢的体外敏感试验不能正确反映临床的治疗效果。实验室应加强阴肠杆菌产酶情况的检测，治疗产酶阴沟肠杆菌引起的感染，首选亚胺培南，其次为舒普深，任何情况下应避免使用三代头孢。     

Central venous catheter-related Rhodotorula rubra fungemia

With the increased use of indwelling central venous catheters, increasing numbers of cases of Rhodotorula fungemia have been observed in patients with neoplasia and neutropenia. In most patients with catheter-related Rhodotorula fungemia, the condition has been treated with broadspectrum antibiotics. We report two cases of central venous catheter-related Rhodotorula rubra fungemia that occurred in patients with acute myeloblastic leukemia. Both patients were in a state of neutropenia. One patient was treated with amphotericin B and his central venous catheter was removed, but he died of Klebsiella pneumoniae bacteremia. The other patient was treated with amphotericin B and discharged, with a central venous catheter, after recovery from neutropenia. Although the management of catheter-related Rhodotorula fungemia infections remains controversial, resolution of the underlying disease is more important than catheter removal for recovery from Rhodotorula rubra fungemia. Received: August 22, 2001 / Accepted: October 8, 2001     

Measuring the Quality of Hospital-based Domestic Violence Programs

OBJECTIVE: To obtain consensus among a panel of experts on performance measures useful for evaluating the quality of hospital-based domestic violence (DV) programs. METHODS: The Delphi process of consensus development was used with a panel of 18 experts including DV researchers, program planners, and advocates. Three rounds were conducted over a period of six months, with each round involving the completion of a written questionnaire. Panelists were instructed to concentrate on structure and process measures of DV program performance. Health outcome measures were not considered. During each round, panelists rated (scale of 1-5) their level of agreement with each measure, in terms of the measure's usefulness for evaluating hospital-based DV programs. Data were entered into SPSS on a personal computer and frequency distributions, measures of central tendency, and variance were computed for each measure. Consensus development was defined as a reduction in the item-specific variance from one round to the next. RESULTS: A total of 37 performance measures were agreed upon. These measures fell within nine different domains of DV program activities, including: Policies and Procedures, Hospital Physical Environment, Hospital Cultural Environment, Training of Providers, Screening and Safety Assessment, Documentation, Intervention Services, Evaluation Activities, and Collaboration. CONCLUSIONS: A number of measures have been identified as useful for evaluating hospital-based DV programs. Use of these measures should assist researchers, program planners, and administrators in assessing the quality of hospital-based DV programs.     

Quality in Clinical Practice

This paper reports the proceedings of the discussion panel assigned to look at clinical aspects of quality in emergency medicine. One of the seven stated objectives of the Academic Emergency Medicine consensus conference on quality in emergency medicine was to educate emergency physicians regarding quality measures and quality improvement as essential aspects of the practice of emergency medicine. Another topic of interest was a discussion of the value of information technology in facilitating quality care in the clinical practice of emergency medicine. It is important to note that this is not intended to be a comprehensive review of this extensive topic, but instead is designed to report the discussion that occurred at this session of the consensus conference.     

Prophylactic nasal continuous positive airway pressure after major vascular surgery: results of a prospective randomized trial

BACKGROUND: The efficacy of nasal continuous positive airway pressure (nCPAP) as a prophylactic method for preventing cardiopulmonary complications after major vascular surgery has not been investigated. PATIENTS/METHODS: In a prospective randomized trial, 204 patients undergoing elective midline laparotomy for vascular surgery were randomized to receive standard therapy ( n=105) or additional prophylactic nCPAP ( n=99) for the first postoperative night. Postoperative oxygenation, incidence of severe cardiac, and pulmonary complications, length of intensive care surveillance and length of total postoperative hospital stay (LOS) were compared. RESULTS: Prophylactic nCPAP significantly reduced the number of patients with severe oxygenation disturbances defined as paO(2) < 70 mmHg with FiO(2) > or = 0.7 (5 versus 17, P=.01). There were no differences with respect to death, cardiac and pulmonary complications, length of intensive care surveillance or LOS. CONCLUSION: Prophylactic 12 h nCPAP significantly reduces the occurrence of postoperative oxygenation disturbances but has no effect on cardiac or pulmonary complications, need for intensive care, LOS or mortality after major vascular surgery.