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Since the turn of the century, robotic-assisted colorectal surgery has been synonymous with the da Vinci® robotic surgical system. We report in this study our first results in robotic-assisted sigmoid resection for diverticular disease using the Senhance™ Surgical Robotic System, while introducing a standardized roadmap for engaging the robotic arms. 12 patients underwent a sigmoid resection using the Senhance™ Surgical Robotic System. All four arms of the robotic system were engaged during all procedures according to a previously devised roadmap. A 4-trocar technique was used in all patients. Perioperative data, including those regarding technical difficulties, were collected and analyzed. Two procedures were converted into standard laparoscopy. There were no conversions to open surgery. The mean age of the patients was 62.5 years (47-79). One third of the patients were males. The mean BMI was 27 kg/m2 (19-38). The mean operative time, the mean console time and the mean docking time were 219 min (204-305), 149 min (124-205) and 10 min (6-15), respectively. The mean length of stay was 9 days (6-15). There was one major complication (8.3%, Clavien-Dindo IIIb). There were no mortalities. No other complications were observed. No patients were readmitted after discharge. The Senhance™ Surgical Robotic System can be used safely in sigmoid resection for diverticular disease after adequate training and systematic planning of the different steps of the procedure. Further experience is needed to judge the benefit for patient and surgeon, as well as the cost and time effectiveness.

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Formulations of quantum mechanics (QM) can be characterized as realistic, operationalist, or a combination of the two. In this paper a realistic theory is defined as describing a closed system entirely by means of entities and concepts pertaining to the system. An operationalist theory, on the other hand, requires in addition entities external to the system. A realistic formulation comprises an ontology, the set of (mathematical) entities that describe the system, and assertions, the set of correct statements (predictions) the theory makes about the objects in the ontology. Classical mechanics is the prime example of a realistic physical theory. A straightforward generalization of classical mechanics to QM is hampered by the inconsistency of quantum properties with classical logic, a circumstance that was noted many years ago by Birkhoff and von Neumann. The present realistic formulation of the histories approach originally introduced by Griffiths, which we call 'compatible quantum theory (CQT)', consists of a 'microscopic' part (MIQM), which applies to a closed quantum system of any size, and a 'macroscopic' part (MAQM), which requires the participation of a large (ideally, an infinite) system. The first (MIQM) can be fully formulated based solely on the assumption of a Hilbert space ontology and the noncontextuality of probability values, relying in an essential way on Gleason's theorem and on an application to dynamics due in large part to Nistico. Thus, the present formulation, in contrast to earlier ones, derives the Born probability formulas and the consistency (decoherence) conditions for frameworks. The microscopic theory does not, however, possess a unique corpus of assertions, but rather a multiplicity of contextual truths ('c-truths'), each one associated with a different framework. This circumstance leads us to consider the microscopic theory to be physically indeterminate and therefore incomplete, though logically coherent. The completion of the theory requires a macroscopic mechanism for selecting a physical framework, which is part of the macroscopic theory (MAQM). The selection of a physical framework involves the breaking of the microscopic 'framework symmetry', which can proceed either phenomenologically as in the standard quantum measurement theory, or more fundamentally by considering the quantum system under study to be a subsystem of a macroscopic quantum system. The decoherent histories formulation of Gell-Mann and Hartle, as well as that of Omnès, are theories of this fundamental type, where the physical framework is selected by a coarse-graining procedure in which the physical phenomenon of decoherence plays an essential role. Various well-known interpretations of QM are described from the perspective of CQT. Detailed definitions and proofs are presented in the appendices.

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BACKGROUND AND OBJECTIVE: The involvement of the cervical spine in rheumatoid arthritis can be essential regarding prognosis and mortality. The cervical myelopathy due to pannus formation and/or subluxation can be fatal. Aim of this study was to demonstrate the possible changes seen by MRI, and to establish a risk-profile for the individual patient. PATIENTS AND METHOD: Within a period of 24 months 214 patients with active RA were included. Clinical and laboratory data were obtained and plain radiographs of the cervical spine were taken. In patients with pathological findings on X-ray an MRI was performed (36 patients). RESULTS: Within the group of 214 patients 36 were identified to get an cervical spine MRI. In all cases the MRI showed significant changes: in 7 (19.5 %) pannus surrounded the dens, with additional erosions in one patient (2.7 %). In 25 (69.5 %) atlanto-axial-subluxation was present, 7 (19.5 %) showed a spondylodiscitis below C2. In 10 (27.8 %) a cervical myelopathy due to pannus or subluxation was present. There was no correlation of the MRI-results with symptoms and findings by examination. The patients with cervical spine disease were in all stages of RA. The majority was rheumatoid-factor positive. 5 out of 10 patients with cervical myelopathy showed neurological deficits: 3 patients died in consequence of neural compression, 2 patients underwent surgery successfully. CONCLUSION: The early detection of a cervical spine involvement in RA is essential to avoid possibly fatal complications. The only reliable method to achieve this goal has to include radiographic diagnostic including MRI of the cervical spine. Only this approach can answer the question of the right time-point for surgery. In daily clinical practice the cervical-spine involvement in RA is still underestimated.

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Osteoclasts are macrophage-derived polykaryons that degrade bone in an acidic extracellular space. This differentiation includes expression of proteinases and acid transport proteins, cell fusion, and bone attachment, but the sequence of events is unclear. We studied two proteins expressed at high levels only in the osteoclast, cathepsin K, a thiol proteinase, and tartrate-resistant acid phosphatase (TRAP), and compared this expression with acid transport and bone degradation. Osteoclastic differentiation was studied using human apheresis macrophages cocultured with MG63 osteosarcoma cells, which produce cytokines including RANKL and CSF-1 that mediate efficient osteoclast formation. Immunoreactive cathepsin K appeared at 3-5 days. Cathepsin K activity was seen on bone substrate but not within cells, and cathepsin K increased severalfold during further differentiation and multinucleation from 7 to 14 days. TRAP also appeared at 3-5 d, independently of cell fusion or bone attachment, and TRAP activity reached much higher levels in osteoclasts attached to bone fragments. Two proteinases that occur in the precursor macrophages, cathepsin B, a thiol proteinase related to cathepsin K, and an unrelated lysosomal aspartate proteinase, cathepsin D, were also studied to determine the specificity of the differentiation events. Cathepsin B occurred at all times, but increased two- to threefold in parallel with cathepsin K. Cathepsin D activity did not change with differentiation, and secreted activity was not significant. In situ acid transport measurements showed increased acid accumulation after 7 days either in cells on osteosarcoma matrix or attached to bone, but bone pit activity and maximal acid uptake required 10-14 days. We conclude that TRAP and thiol proteinase expression begin at essentially the same time, and precede cell fusion and bone attachment. However, major increases in acid secretion and proteinases expression continue during cell fusion and bone attachment from 7 to 14 days.

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OBJECTIVE: To examine the removal of vancomycin during plasmapheresis, determine whether drug administration should be withheld prior to or a supplemental dose given after the procedure, and determine whether a redistribution phenomenon in vancomycin serum concentrations occurs after plasmapheresis. DESIGN: Prospective, cohort study. SETTING: An 800-bed, tertiary-care, teaching hospital. PATIENTS: Twelve patients receiving vancomycin as prescribed who were also undergoing therapeutic plasmapheresis. METHODS: Blood samples for determination of vancomycin concentrations were obtained from each patient immediately before, during, immediately after, and 2 hours after plasmapheresis. Vancomycin concentration in plasma removed by plasmapheresis and volume of plasma removed were measured. Patient-specific pharmacokinetic parameters were determined for each patient using serum concentration data and a one-compartment model. Percent of drug removed by plasmapheresis and percent increase in vancomycin total clearance secondary to plasmapheresis were calculated. RESULTS: A mean of 6.3% of the total body store of vancomycin was removed by plasmapheresis. Vancomycin clearance during plasmapheresis averaged 1.6 L/h, which was an average increase of 285% in the total clearance of vancomycin from the body. Nine of 10 patients had a higher observed vancomycin concentration 2 hours after plasmapheresis than that predicted by degrading the concentration observed immediately after the procedure, suggesting that redistribution in serum concentrations occurs after the procedure. CONCLUSIONS: A single one-volume plasmapheresis does not remove a clinically important amount of vancomycin; therefore, supplemental dosing after the procedure is not necessary. A redistribution phenomenon in vancomycin concentrations appears to exist after plasmapheresis. Further study is needed to determine how long the redistribution phase lasts and when vancomycin concentrations should be measured after plasmapheresis.

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Implementation of guidelines offers one of the largest opportunities for quality improvement, utilization review, and cost control for the health-care enterprise. If guidelines could be implemented on a large scale, their adoption could result in $100 billion in annual savings as well as improve the quality of patient care. However, infrastructural barriers impede progress. Collaboration between the Laboratory Medicine Health Services Program at the University of Alabama at Birmingham, Columbia-Presbyterian Medical Center, and the Cerner Corporation, funded by the National Institute of Standards and Technology as part of the Advanced Technology Program involving ¿Information Infrastructure for Healthcare,¿ is focused on developing and delivering: 1) methods for creating operational forms of guidelines; 2) an effective computer-based architecture for implementing guidelines in clinical practice; 3) methods for packaging guidelines for wide distribution; 4) methods for testing the efficacy, safety, and acceptability of guidelines; and 5) a model for collecting, aggregating, and normalizing data from disparate systems. This hypothesis-driven research program is focused on laboratory medicine-based guidelines as a tool for developing, testing, and evaluating methods that can be implemented widely.

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Of the spectrum of clinical and laboratory factors responsible for refractoriness to platelet transfusions, some are amenable to intervention, some to circumvention, and others only to acceptance and support for complications. Identification of the likely reason for refractoriness in a given individual patient is critical to determine the optimum management strategy. The blood bank or transfusion service can and perhaps should play a direct role in that strategy through the provision of single donor platelets collected by apheresis. Single donor platelets offer a number of real and theoretical advantages over random donor platelets, including the potential for crossmatching, reduction in net donor exposures, maintenance of ABO-compatibility, improved inventory management, and perhaps diminished rate of alloimmunization. The sole perceived benefits of random donor platelets are cost and availability. The cost differential, however, needs to take into account a variety of factors beyond the immediate concern of platelet collection and distribution, including many highly dependent upon local factors. The optimum management of the platelet refractory patient requires more appropriate use of single donor apheresis platelets coupled with platelet crossmatching when necessary. Data from outcomes studies presented indicates that increased reliance upon single donor apheresis platelets at the expense of pooled random donor units can improve the overall quality of transfusion practice by decreasing platelet utilization, resource consumption, donor exposures, and platelet wastage.

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Platelet refractoriness is a multifactorial problem that often leads to aggressive measures in an attempt to treat a thrombocytopenic patient. Identification of the underlying causes should allow for prevention and management regimens to improve both transfusion practice and patient outcome. A number of clinical studies have evaluated the relative importance of the various causes of refractoriness. Unfortunately, most are significantly compromised by uncontrolled confounding factors. The causes can be broken down into three categories based on the source of the problem: clinically determined, patient related, or blood bank determined. This breakdown can help to identify appropriate prevention and circumvention measures. Additional causes worthy of increased attention are the platelet transfusion trigger and the tendency for prophylactic transfusion. Improvements in transfusion practice may offer the greatest hope for limiting the complications of platelet transfusion and refractoriness.

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This article addresses the theoretical conceptualization of depressive typology proposed by Blatt (1974) by analyzing selected items on the Depressive Experiences Questionnaire (DEQ) in a 21-item modified version. Items were selected by judges and by factor loading criteria to be most theoretically characteristic of the dimensions they are meant to represent: anaclitic and introjective depression. Two independent samples, a female inpatient sample and a female college sample, were used. Principal components analysis of these 21 items revealed only 5 anaclitic items and 7 introjective items that loaded on their respective factors for both samples. Inspection of these items suggests that the anaclitic depressive experience is characterized by discomfort with interpersonal separation, whereas the introjective experience is characterized by negative self-evaluation with respect to self-imposed standards. Other putative aspects of these two depressive dimensions were not supported by this study; particularly, guilt and self-blame were not associated with introjective depression.

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Severe transfusion reactions occur much less often than minor reactions, but it is difficult to discriminate clinically between impending severe reactions and minor reactions. Therefore, whenever a reaction occurs, the transfusion should be discontinued and a laboratory workup initiated to rule out an acute hemolytic transfusion reaction. At a minimum, a direct antiglobulin (Coombs') test should be performed, and specimens obtained before and after transfusion should be assayed for hemoglobinemia and hemoglobinuria. If the product transfused included red blood cells, then typing and crossmatching should be repeated on a posttransfusion blood specimen. Routine premedication with antipyretics is not recommended, since they may mask early signs and symptoms of more severe reactions and their efficacy is questionable. Recent insights into the mechanisms of transfusion reactions have suggested interventions that may help minimize or prevent potentially serious sequelae.

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Optimal transfusion therapy for the patient undergoing stem cell transplantation will vary, depending on a variety of independent factors. These factors include the source of hematopoietic progenitor cells, The relationship between donor and recipient, and the timing of the transfusion relative to the transplant. Stem cell transplantation also changes the traditional views of blood groups: a patient may have more than one of the traditional blood groups at different stages of transplantation.

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Transfusion medicine has emerged in the wake of therapeutic successes in almost every branch of medicine to optimize blood product support and minimize consequent complications. The role of transfusion therapy has become increasingly more critical as improved therapeutic regimens augment the survival of the patient with malignancy. Perhaps more so than in any other field, recognition of long-term sequelae of transfusion in oncology depends upon short-term success. Every day, blood products are collected, selected, modified, and created with specific clinical intentions in mind. The practitioner in hematology/oncology needs to understand both the benefits and consequences of transfusion therapy, with an increased emphasis on the long-term implications and complications.

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