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Novel biochemical sensors consisting of rotating chains of microscale paramagnetic particles have been proposed that would enable convenient, sensitive analyte detection. Predicting the dynamics of these particles is required to optimise their design. The results of lattice Boltzmann (LB) and particle dynamics (PD) simulations are reported, where the LB approach provides a verified solution of the complete Navier-Stokes equations, including the hydrodynamic interactions among the particles. On the other hand, the simpler PD approach neglects hydrodynamic interactions, and does not compute the fluid motion. It is shown that macroscopic properties, like the number of aggregated particles, depend only on the drag force and not on the total hydrodynamic force, making PD simulations yield reasonably accurate predictions. Relatively good agreement between the LB and PD simulations, and qualitative agreement with experimental data, are found for the number of aggregated particles as a function of the Mason number. The drag force on a rotating cylinder is significantly different from that on particle chains calculated from both simulations, demonstrating the different dynamics between the two cases. For microscopic quantities like the detailed force distributions on each particle, the complete Navier-Stokes solution, here represented by the LB simulation, is required.

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Mixing in microscale flows with rotating chains of paramagnetic particles can be enhanced by adjusting the ratio of viscous to magnetic forces so that chains dynamically break and reform. Lattice Boltzmann (LB) simulations were used to calculate the interaction between the fluid and suspended paramagnetic particles under the influence of a rotating magnetic field. Fluid velocities obtained from the LB simulations are used to solve the advection diffusion equation for massless tracer particles. At relatively high Mason numbers, small chains result in low edge velocities, and hence mixing is slower than at other Mason numbers. At low Mason numbers, long, stable chains form and produce little mixing toward the center of the chains. A peak in mixing rate is observed when chains break and reform. The uniformity of mixing is greater at higher Mason numbers because more small chains result in a larger number of small mixing areas.

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BACKGROUND: Cancer-associated, major histocompatibility complex (MHC)-restricted peptide antigens have been elucidated in human melanomas and ovarian, breast, and renal carcinomas; but relatively little is known about lung cancer antigens. METHODS: To work toward delineation of lung cancer-associated antigens, we developed tumor infiltrating lymphocytes (TILs), peripheral blood mononuclear cell-derived cytolytic T cell lines (CTL), autologous lung cancer cell lines, and normal lung cell lines from 17 patients undergoing lung cancer resections. The TILs and CTL lines were subsequently evaluated for markers of activation and specific lysis of autologous or allogeneic lung cancer cell lines or both. RESULTS: Freshly isolated TILs contained a more activated T cell population compared with the patients' peripheral blood T cells as evidenced by an increased expression of HLA-DR, CD25, and CD45RO. TILs isolated from 15 patients lysed allogeneic lung cancer lines. TILs lysed autologous lung cancer but not autologous normal lung or Epstein-Barr virus transformed B cell lines (B-LCL) in 4 of 8 cases tested, suggesting tumor specificity. A CTL line (RHPBL57.1) was generated from peripheral blood mononuclear cells of an HLA-A24(+) patient by stimulation against an established HLA-A24(+) allogeneic lung cancer cell line. RHPBL57.1 lysed the lung cancer cell line in an HLA-A24-restricted manner. Moreover, RHPBL57.1 specifically lysed autologous B-LCL pulsed with peptides, eluted from MHC class I and isolated from the HLA-A24(+) lung cancer cell line. CONCLUSIONS: TILs isolated from patients with lung cancer are predominantly an activated population of T cells with evidence of tumor and MHC class I-restricted lysis. Furthermore, we provide evidence for a lung cancer-associated, MHC class I-bound peptide antigen(s) that reconstitutes the epitope recognized by a lung cancer specific CD8(+) T cell line derived from a patient with lung cancer.

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BACKGROUND: Intercellular adhesion molecule (ICAM-1) is important in leukocyte adhesion-dependent events and some data suggest that ICAM-1 provides T cell costimulation. We anlayzed the role of the ICAM-1 and leukocyte function associated antigen-1 (LFA-1) interaction in human T cell alloreactivity in vitro. METHODS: Allo-antigen-induced T cell proliferation and cytotoxic T lymphocyte lytic activity were assessed by mixed lymphocyte reaction assay and 51 Chromium release assay, respectively. Immunostaining and flow cytometry were used to assess the expression of receptors on activated T cells. RESULTS: Alloantigen-induced T cell proliferation and cytotoxic T lymphocyte activity were markedly inhibited by antibodies to ICAM-1 and LFA-1. These antibodies had to be present at the time of initial T cell receptor/antigen engagement to inhibit proliferation. Neither IL-2 nor IL-4 were involved in the observed inhibition by antibodies. Inhibition was not associated with altered cell surface expression of receptors such as CD3, CD4, ICAM-1, LFA-1, CD25, and HLA-DR however, these antibodies did impede the ability of generation of functionally active T cells. Interestingly, these antibodies inhibited soluble, but not immobilized OKT3-induced proliferation of peripheral blood leukocytes. Antibody-mediated inhibition of proliferation failed to impair the ability of T cells to subsequently proliferate in response to stimulation by the original or third party alloantigen or mobilize [Ca++]i in response to CD3 or LFA-1 receptor ligation. CONCLUSIONS: These data demonstrate that blockade of ICAM-1/LFA-1 binding at the time of allorecognition potently blocks initial T cell effector functions that could be due to lack of effective T cell/APC engagement.

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OBJECTIVE: To review the results of the authors' most recent 100 consecutive cases of transcervical thymectomy for myasthenia gravis (MG) in terms of complications and outcome in comparison with other reported techniques. SUMMARY BACKGROUND DATA: Myasthenia gravis is believed to be an autoimmune disorder characterized by increasing fatigue with exertion. The role of thymectomy in the management of the disease remains unproven, but there is widespread acceptance of the notion that complete thymectomy improves the course of the disease. Complete excision of the thymus is the goal in all cases; however, the best technique to achieve complete thymectomy remains controversial. The authors favor a transcervical approach through a small collar incision aided by a specially designed sternal retractor. Others prefer a transsternal, a combined transcervical and transsternal ("maximal"), or a video-assisted thoracoscopic surgical approach. METHODS: A retrospective review of the authors' most recent 100 consecutive transcervical thymectomies for nonthymoma-associated MG was performed using medical records and telephone interviews. Patients' symptoms were graded before surgery and at the most recent (within the last 6 months) postoperative time point, using the modified Osserman classification: 0 = asymptomatic, 1 = ocular signs and symptoms, 2 = mild generalized weakness, 3 = moderate generalized weakness, bulbar dysfunction, or both, and 4 = severe generalized weakness, respiratory dysfunction, or both. RESULTS: There were 61 female patients and 39 male patients with a mean age of 38 years (range, 14 to 84). The median hospital stay was 1 day. There were no deaths and no significant complications. Seventy-eight patients who had undergone surgery >12 months ago were available for analysis. In these patients, with a mean follow-up time of 5 years (median 5.3; range, 12 months to 10 years), the median preoperative Osserman grade improved from 3.0 (mean 2.73) before surgery to 1.0 after surgery (mean 0.94). CONCLUSIONS: The transcervical approach for thymectomy for the treatment of MG produces results similar to those of other surgical approaches, with the added benefits of shortened hospital stay, decreased complications, reduced cost, and broader physician and patient acceptance of surgical treatment.

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Bronchiolitis Obliterans Syndrome (BOS) remains the overwhelming obstacle to the success of lung transplantations (LTx). The presence of donor-specific microchimerism (DSM) and its association with lung allograft function is not well defined. To investigate the relationship between chimerism and BOS, blood was obtained from 21 LTx recipients. Genomic DNA was isolated from patient blood, and PCR-based techniques were used to identify recipient and donor HLA-DR. Fifty percent of the LTx recipients with BOS exhibited DSM at "T1" time post transplant, and 40% at one year follow-up (T2). However, 54% exhibited DSM in the BOS-free group at T1, and 44% at T2. Of the BOS-free, DSM-positive patients at T1, 29% developed BOS by T2. In contrast, 50% of BOS-free DSM-negative patients 50% developed BOS (P > 0.05). Double LTx had a higher prevalence of DSM (73%) and a lower prevalence of BOS (46%) than single LTx (50% and 80% respectively, P > 0.05). One-HLA-DR-antigen-matched LTx recipients show a low prevalence of DSM compared to non-matched (P < 0.05). This study demonstrates that the development of BOS in LTx recipients could also occur in the presence of blood chimerism.

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The Kentucky Emergency Medical Services Information System was formed in 1993 to establish a centralized registry of prehospital and emergency department data. These data can aid individual providers in planning and providing patient services and state planners in systems development and disease surveillance. This article seeks to provide an overview of the system for providers of acute care services in Kentucky, its current capabilities and future goals.

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The objective of this study was to analyze, by retrospective review, the pediatric population utilizing emergency medical services (EMS) throughout Kentucky, with particular emphasis on differences between urban and rural areas. The source of the data used was from all prehospital runs in children less than 17 years of age reported in Kentucky in a computerized database to the state EMS branch. There were no interventions. We found that pediatric calls were more frequent in adolescents than younger children. Trauma was more frequent in older children and in rural settings and accounted for nearly 50% of all calls. Motor vehicle accidents were the most frequent cause of traumatic injuries. Run times were prolonged in the rural setting, but this was a reflection of transport rather than scene times. The use of basic life support (BLS) and advanced life support (ALS) procedures was dependent on the patient's age and the level of care of the provider. ALS procedures were infrequently performed, especially in younger patients, although the performance of these procedures did not prolong scene times. We conclude that educational initiatives for pediatric care in the prehospital setting should include assessment and stabilization of children, including appropriate procedures, both for ALS and BLS providers. Prehospital data should be linked with police reports and emergency department data to provide means of assessing the impact of prehospital services on outcome in pediatric patients.

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OBJECTIVE: To categorize the level of care offered in emergency settings at acute care hospitals in Kentucky. DESIGN: Survey mailed to all hospitals in the state. MEASUREMENTS/MAIN RESULTS: Hospital capabilities for both adult and pediatric patients were assessed by strict adherence to a set of preset objective requirements and by a subjective review of the resources available to the acutely injured patient, based on the responses to a mailed questionnaire. There are three level 1 and nine level 2 hospitals available to adults and two level 1 and seven level 2 hospitals available to children in Kentucky. Thirty-five counties are without an acute care hospital. Objective- and subjective-based classification were discordant in approximately 25% of hospitals. Current referral patterns reflect this categorization, but referral is most often directly to level 1 centers. CONCLUSIONS: We have established a set of criteria to categorize the level of care acutely available to injured patients in Kentucky which can be simply implemented. In developing statewide systems of care, strict adherence to preset criteria may not accurately reflect the true resources available. With the lack of a planned and organized system, current referral patterns reflect transfer of patients directly to level 1 centers, which may result in overtriage and underutilization of level 2 or level 3 hospitals.

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The Minnesota Multiphasic Personality Inventory (MMPI; Hathaway & McKinley, 1943) Cook-Medley Hostility scale (Ho) has been studied a great deal because of its relation to coronary disease and mortality. However, little research has been conducted with the Ho scale on the revised MMPI (MMPI-2; Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989). This study examined the psychometric characteristics of the MMPI-2 Ho scale. Only nine of the original 50 Ho items were slightly changed in the revision. Ho scores were highly correlated with MMPI-2 scales CYN, K, TPA, and ASP, supporting the interpretation of Ho as a measure of cynicism. High correlations with other MMPI-2 scales also suggested that Ho is related to general psychopathology and negative affectivity. Male Ho scorers were rated by their spouses as hotheaded, bossy, demanding, and argumentative. For women, Ho scale scores were less strongly associated with ratings of overt hostility. Principal components analysis of Ho revealed four underlying dimensions: Cynicism, Hypersensitivity, Aggressive Responding, and Social Avoidance.

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Automated external defibrillators (AED) have been authorized for use by Emergency Medical Technicians (EMT) in Kentucky since March 1991. Emergency Medical Services (EMS) which use these devices are required to submit annual reports to the EMS Branch. During 1992, 17 services were approved to use AEDs. The device was used by 12 services on 93 victims of out-of-hospital cardiac arrest. Of the 93 victims, 27 were defibrillated, eight were resuscitated to hospital admission, and three survived to hospital discharge. The overall survival rate was 3/93 (3.2%). For patients receiving defibrillatory shocks, the survival rate was 3/27 (11%). This percentage is comparable with the survival rates reported from other predominately rural states where AEDs have been used by EMTs. Possible protocol violations and inadequate documentation were also identified from these reports. In summary, EMTs in predominately rural Kentucky can use AEDs to achieve survival rates for out-of-hospital cardiac arrest comparable with other rural states.

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To further investigate the relationship between gallbladder disease and morbid obesity, 92 morbidly obese patients underwent routine cholecystectomy at the time of their bariatric procedures. The preoperative ultrasonographic findings were positive in only 20 patients. Of the 92 patients who underwent cholecystectomy, 87 (95 percent) had pathologic evidence of gallbladder disease. This included cholecystitis, cholesterolosis, cholelithiasis, or some combination of the three. The incidence of postoperative cholecystitis, the technical difficulty of reoperation, the unnecessary expense and exposure to a second hospitalization and a second operation are all completely eliminated when routine cholecystectomy is performed in concert with elective bariatric procedures.

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The purpose of the present study was to test the findings of Botwinick's work on cautiousness and decision-making in old age [1,2], along with an examination of two factors not previously studied: rigidity and certainty of decision outcome. Sixty-four elderly participants of both sexes participated in filling out the Choice Dilemmas Questionnaire (CDQ) after having been classified as high or low on Schaie's Test of Behavioral Rigidity [3]. In general, Botwinick's conclusions were supported: 1. when given the opportunity to avoid making decisions on the CDQ, the elderly did so, even under conditions of no risk at all concerning the outcome of the decision; 2. elderly individuals appeared to become more conservative and cautious in their decisions when the outcome was directed at the lives of young individuals than when older individual's lifestyles were of concern. This latter phenomenon, however was not seen when the elderly participant was required to make a decision and could not elect to abstain. In addition, rigidity was found to be related to risky decisions made by the elderly individual.

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The technique described in this study demonstrates that the use of orthodontic extrusion can provide an alternative to extraction and extensive periodontal surgery. Selection of patients is an important aspect when considering this type of treatment. The crown-root ratio, as well as the root anatomy, if inadequate, may render this type of treatment inappropriate. The concept of a biologic width is discussed, and its application to forced eruption is described.

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